diff options
Diffstat (limited to 'generic/tkTextDisp.c')
| -rw-r--r-- | generic/tkTextDisp.c | 5015 |
1 files changed, 5015 insertions, 0 deletions
diff --git a/generic/tkTextDisp.c b/generic/tkTextDisp.c new file mode 100644 index 0000000..8d9c022 --- /dev/null +++ b/generic/tkTextDisp.c @@ -0,0 +1,5015 @@ +/* + * tkTextDisp.c -- + * + * This module provides facilities to display text widgets. It is + * the only place where information is kept about the screen layout + * of text widgets. + * + * Copyright (c) 1992-1994 The Regents of the University of California. + * Copyright (c) 1994-1997 Sun Microsystems, Inc. + * + * See the file "license.terms" for information on usage and redistribution + * of this file, and for a DISCLAIMER OF ALL WARRANTIES. + * + * SCCS: @(#) tkTextDisp.c 1.124 97/07/11 18:01:03 + */ + +#include "tkPort.h" +#include "tkInt.h" +#include "tkText.h" + +/* + * The following structure describes how to display a range of characters. + * The information is generated by scanning all of the tags associated + * with the characters and combining that with default information for + * the overall widget. These structures form the hash keys for + * dInfoPtr->styleTable. + */ + +typedef struct StyleValues { + Tk_3DBorder border; /* Used for drawing background under text. + * NULL means use widget background. */ + int borderWidth; /* Width of 3-D border for background. */ + int relief; /* 3-D relief for background. */ + Pixmap bgStipple; /* Stipple bitmap for background. None + * means draw solid. */ + XColor *fgColor; /* Foreground color for text. */ + Tk_Font tkfont; /* Font for displaying text. */ + Pixmap fgStipple; /* Stipple bitmap for text and other + * foreground stuff. None means draw + * solid.*/ + int justify; /* Justification style for text. */ + int lMargin1; /* Left margin, in pixels, for first display + * line of each text line. */ + int lMargin2; /* Left margin, in pixels, for second and + * later display lines of each text line. */ + int offset; /* Offset in pixels of baseline, relative to + * baseline of line. */ + int overstrike; /* Non-zero means draw overstrike through + * text. */ + int rMargin; /* Right margin, in pixels. */ + int spacing1; /* Spacing above first dline in text line. */ + int spacing2; /* Spacing between lines of dline. */ + int spacing3; /* Spacing below last dline in text line. */ + TkTextTabArray *tabArrayPtr;/* Locations and types of tab stops (may + * be NULL). */ + int underline; /* Non-zero means draw underline underneath + * text. */ + Tk_Uid wrapMode; /* How to handle wrap-around for this tag. + * One of tkTextCharUid, tkTextNoneUid, + * or tkTextWordUid. */ +} StyleValues; + +/* + * The following structure extends the StyleValues structure above with + * graphics contexts used to actually draw the characters. The entries + * in dInfoPtr->styleTable point to structures of this type. + */ + +typedef struct TextStyle { + int refCount; /* Number of times this structure is + * referenced in Chunks. */ + GC bgGC; /* Graphics context for background. None + * means use widget background. */ + GC fgGC; /* Graphics context for foreground. */ + StyleValues *sValuePtr; /* Raw information from which GCs were + * derived. */ + Tcl_HashEntry *hPtr; /* Pointer to entry in styleTable. Used + * to delete entry. */ +} TextStyle; + +/* + * The following macro determines whether two styles have the same + * background so that, for example, no beveled border should be drawn + * between them. + */ + +#define SAME_BACKGROUND(s1, s2) \ + (((s1)->sValuePtr->border == (s2)->sValuePtr->border) \ + && ((s1)->sValuePtr->borderWidth == (s2)->sValuePtr->borderWidth) \ + && ((s1)->sValuePtr->relief == (s2)->sValuePtr->relief) \ + && ((s1)->sValuePtr->bgStipple == (s2)->sValuePtr->bgStipple)) + +/* + * The following structure describes one line of the display, which may + * be either part or all of one line of the text. + */ + +typedef struct DLine { + TkTextIndex index; /* Identifies first character in text + * that is displayed on this line. */ + int count; /* Number of characters accounted for by this + * display line, including a trailing space + * or newline that isn't actually displayed. */ + int y; /* Y-position at which line is supposed to + * be drawn (topmost pixel of rectangular + * area occupied by line). */ + int oldY; /* Y-position at which line currently + * appears on display. -1 means line isn't + * currently visible on display and must be + * redrawn. This is used to move lines by + * scrolling rather than re-drawing. */ + int height; /* Height of line, in pixels. */ + int baseline; /* Offset of text baseline from y, in + * pixels. */ + int spaceAbove; /* How much extra space was added to the + * top of the line because of spacing + * options. This is included in height + * and baseline. */ + int spaceBelow; /* How much extra space was added to the + * bottom of the line because of spacing + * options. This is included in height. */ + int length; /* Total length of line, in pixels. */ + TkTextDispChunk *chunkPtr; /* Pointer to first chunk in list of all + * of those that are displayed on this + * line of the screen. */ + struct DLine *nextPtr; /* Next in list of all display lines for + * this window. The list is sorted in + * order from top to bottom. Note: the + * next DLine doesn't always correspond + * to the next line of text: (a) can have + * multiple DLines for one text line, and + * (b) can have gaps where DLine's have been + * deleted because they're out of date. */ + int flags; /* Various flag bits: see below for values. */ +} DLine; + +/* + * Flag bits for DLine structures: + * + * HAS_3D_BORDER - Non-zero means that at least one of the + * chunks in this line has a 3D border, so + * it potentially interacts with 3D borders + * in neighboring lines (see + * DisplayLineBackground). + * NEW_LAYOUT - Non-zero means that the line has been + * re-layed out since the last time the + * display was updated. + * TOP_LINE - Non-zero means that this was the top line + * in the window the last time that the window + * was laid out. This is important because + * a line may be displayed differently if its + * at the top or bottom than if it's in the + * middle (e.g. beveled edges aren't displayed + * for middle lines if the adjacent line has + * a similar background). + * BOTTOM_LINE - Non-zero means that this was the bottom line + * in the window the last time that the window + * was laid out. + */ + +#define HAS_3D_BORDER 1 +#define NEW_LAYOUT 2 +#define TOP_LINE 4 +#define BOTTOM_LINE 8 + +/* + * Overall display information for a text widget: + */ + +typedef struct TextDInfo { + Tcl_HashTable styleTable; /* Hash table that maps from StyleValues + * to TextStyles for this widget. */ + DLine *dLinePtr; /* First in list of all display lines for + * this widget, in order from top to bottom. */ + GC copyGC; /* Graphics context for copying from off- + * screen pixmaps onto screen. */ + GC scrollGC; /* Graphics context for copying from one place + * in the window to another (scrolling): + * differs from copyGC in that we need to get + * GraphicsExpose events. */ + int x; /* First x-coordinate that may be used for + * actually displaying line information. + * Leaves space for border, etc. */ + int y; /* First y-coordinate that may be used for + * actually displaying line information. + * Leaves space for border, etc. */ + int maxX; /* First x-coordinate to right of available + * space for displaying lines. */ + int maxY; /* First y-coordinate below available + * space for displaying lines. */ + int topOfEof; /* Top-most pixel (lowest y-value) that has + * been drawn in the appropriate fashion for + * the portion of the window after the last + * line of the text. This field is used to + * figure out when to redraw part or all of + * the eof field. */ + + /* + * Information used for scrolling: + */ + + int newCharOffset; /* Desired x scroll position, measured as the + * number of average-size characters off-screen + * to the left for a line with no left + * margin. */ + int curPixelOffset; /* Actual x scroll position, measured as the + * number of pixels off-screen to the left. */ + int maxLength; /* Length in pixels of longest line that's + * visible in window (length may exceed window + * size). If there's no wrapping, this will + * be zero. */ + double xScrollFirst, xScrollLast; + /* Most recent values reported to horizontal + * scrollbar; used to eliminate unnecessary + * reports. */ + double yScrollFirst, yScrollLast; + /* Most recent values reported to vertical + * scrollbar; used to eliminate unnecessary + * reports. */ + + /* + * The following information is used to implement scanning: + */ + + int scanMarkChar; /* Character that was at the left edge of + * the window when the scan started. */ + int scanMarkX; /* X-position of mouse at time scan started. */ + int scanTotalScroll; /* Total scrolling (in screen lines) that has + * occurred since scanMarkY was set. */ + int scanMarkY; /* Y-position of mouse at time scan started. */ + + /* + * Miscellaneous information: + */ + + int dLinesInvalidated; /* This value is set to 1 whenever something + * happens that invalidates information in + * DLine structures; if a redisplay + * is in progress, it will see this and + * abort the redisplay. This is needed + * because, for example, an embedded window + * could change its size when it is first + * displayed, invalidating the DLine that + * is currently being displayed. If redisplay + * continues, it will use freed memory and + * could dump core. */ + int flags; /* Various flag values: see below for + * definitions. */ +} TextDInfo; + +/* + * In TkTextDispChunk structures for character segments, the clientData + * field points to one of the following structures: + */ + +typedef struct CharInfo { + int numChars; /* Number of characters to display. */ + char chars[4]; /* Characters to display. Actual size + * will be numChars, not 4. THIS MUST BE + * THE LAST FIELD IN THE STRUCTURE. */ +} CharInfo; + +/* + * Flag values for TextDInfo structures: + * + * DINFO_OUT_OF_DATE: Non-zero means that the DLine structures + * for this window are partially or completely + * out of date and need to be recomputed. + * REDRAW_PENDING: Means that a when-idle handler has been + * scheduled to update the display. + * REDRAW_BORDERS: Means window border or pad area has + * potentially been damaged and must be redrawn. + * REPICK_NEEDED: 1 means that the widget has been modified + * in a way that could change the current + * character (a different character might be + * under the mouse cursor now). Need to + * recompute the current character before + * the next redisplay. + */ + +#define DINFO_OUT_OF_DATE 1 +#define REDRAW_PENDING 2 +#define REDRAW_BORDERS 4 +#define REPICK_NEEDED 8 + +/* + * The following counters keep statistics about redisplay that can be + * checked to see how clever this code is at reducing redisplays. + */ + +static int numRedisplays; /* Number of calls to DisplayText. */ +static int linesRedrawn; /* Number of calls to DisplayDLine. */ +static int numCopies; /* Number of calls to XCopyArea to copy part + * of the screen. */ + +/* + * Forward declarations for procedures defined later in this file: + */ + +static void AdjustForTab _ANSI_ARGS_((TkText *textPtr, + TkTextTabArray *tabArrayPtr, int index, + TkTextDispChunk *chunkPtr)); +static void CharBboxProc _ANSI_ARGS_((TkTextDispChunk *chunkPtr, + int index, int y, int lineHeight, int baseline, + int *xPtr, int *yPtr, int *widthPtr, + int *heightPtr)); +static void CharDisplayProc _ANSI_ARGS_((TkTextDispChunk *chunkPtr, + int x, int y, int height, int baseline, + Display *display, Drawable dst, int screenY)); +static int CharMeasureProc _ANSI_ARGS_((TkTextDispChunk *chunkPtr, + int x)); +static void CharUndisplayProc _ANSI_ARGS_((TkText *textPtr, + TkTextDispChunk *chunkPtr)); +static void DisplayDLine _ANSI_ARGS_((TkText *textPtr, + DLine *dlPtr, DLine *prevPtr, Pixmap pixmap)); +static void DisplayLineBackground _ANSI_ARGS_((TkText *textPtr, + DLine *dlPtr, DLine *prevPtr, Pixmap pixmap)); +static void DisplayText _ANSI_ARGS_((ClientData clientData)); +static DLine * FindDLine _ANSI_ARGS_((DLine *dlPtr, + TkTextIndex *indexPtr)); +static void FreeDLines _ANSI_ARGS_((TkText *textPtr, + DLine *firstPtr, DLine *lastPtr, int unlink)); +static void FreeStyle _ANSI_ARGS_((TkText *textPtr, + TextStyle *stylePtr)); +static TextStyle * GetStyle _ANSI_ARGS_((TkText *textPtr, + TkTextIndex *indexPtr)); +static void GetXView _ANSI_ARGS_((Tcl_Interp *interp, + TkText *textPtr, int report)); +static void GetYView _ANSI_ARGS_((Tcl_Interp *interp, + TkText *textPtr, int report)); +static DLine * LayoutDLine _ANSI_ARGS_((TkText *textPtr, + TkTextIndex *indexPtr)); +static int MeasureChars _ANSI_ARGS_((Tk_Font tkfont, + CONST char *source, int maxChars, int startX, + int maxX, int tabOrigin, int *nextXPtr)); +static void MeasureUp _ANSI_ARGS_((TkText *textPtr, + TkTextIndex *srcPtr, int distance, + TkTextIndex *dstPtr)); +static int NextTabStop _ANSI_ARGS_((Tk_Font tkfont, int x, + int tabOrigin)); +static void UpdateDisplayInfo _ANSI_ARGS_((TkText *textPtr)); +static void ScrollByLines _ANSI_ARGS_((TkText *textPtr, + int offset)); +static int SizeOfTab _ANSI_ARGS_((TkText *textPtr, + TkTextTabArray *tabArrayPtr, int index, int x, + int maxX)); +static void TextInvalidateRegion _ANSI_ARGS_((TkText *textPtr, + TkRegion region)); + + +/* + *---------------------------------------------------------------------- + * + * TkTextCreateDInfo -- + * + * This procedure is called when a new text widget is created. + * Its job is to set up display-related information for the widget. + * + * Results: + * None. + * + * Side effects: + * A TextDInfo data structure is allocated and initialized and attached + * to textPtr. + * + *---------------------------------------------------------------------- + */ + +void +TkTextCreateDInfo(textPtr) + TkText *textPtr; /* Overall information for text widget. */ +{ + register TextDInfo *dInfoPtr; + XGCValues gcValues; + + dInfoPtr = (TextDInfo *) ckalloc(sizeof(TextDInfo)); + Tcl_InitHashTable(&dInfoPtr->styleTable, sizeof(StyleValues)/sizeof(int)); + dInfoPtr->dLinePtr = NULL; + dInfoPtr->copyGC = None; + gcValues.graphics_exposures = True; + dInfoPtr->scrollGC = Tk_GetGC(textPtr->tkwin, GCGraphicsExposures, + &gcValues); + dInfoPtr->topOfEof = 0; + dInfoPtr->newCharOffset = 0; + dInfoPtr->curPixelOffset = 0; + dInfoPtr->maxLength = 0; + dInfoPtr->xScrollFirst = -1; + dInfoPtr->xScrollLast = -1; + dInfoPtr->yScrollFirst = -1; + dInfoPtr->yScrollLast = -1; + dInfoPtr->scanMarkChar = 0; + dInfoPtr->scanMarkX = 0; + dInfoPtr->scanTotalScroll = 0; + dInfoPtr->scanMarkY = 0; + dInfoPtr->dLinesInvalidated = 0; + dInfoPtr->flags = DINFO_OUT_OF_DATE; + textPtr->dInfoPtr = dInfoPtr; +} + +/* + *---------------------------------------------------------------------- + * + * TkTextFreeDInfo -- + * + * This procedure is called to free up all of the private display + * information kept by this file for a text widget. + * + * Results: + * None. + * + * Side effects: + * Lots of resources get freed. + * + *---------------------------------------------------------------------- + */ + +void +TkTextFreeDInfo(textPtr) + TkText *textPtr; /* Overall information for text widget. */ +{ + register TextDInfo *dInfoPtr = textPtr->dInfoPtr; + + /* + * Be careful to free up styleTable *after* freeing up all the + * DLines, so that the hash table is still intact to free up the + * style-related information from the lines. Once the lines are + * all free then styleTable will be empty. + */ + + FreeDLines(textPtr, dInfoPtr->dLinePtr, (DLine *) NULL, 1); + Tcl_DeleteHashTable(&dInfoPtr->styleTable); + if (dInfoPtr->copyGC != None) { + Tk_FreeGC(textPtr->display, dInfoPtr->copyGC); + } + Tk_FreeGC(textPtr->display, dInfoPtr->scrollGC); + if (dInfoPtr->flags & REDRAW_PENDING) { + Tcl_CancelIdleCall(DisplayText, (ClientData) textPtr); + } + ckfree((char *) dInfoPtr); +} + +/* + *---------------------------------------------------------------------- + * + * GetStyle -- + * + * This procedure creates all the information needed to display + * text at a particular location. + * + * Results: + * The return value is a pointer to a TextStyle structure that + * corresponds to *sValuePtr. + * + * Side effects: + * A new entry may be created in the style table for the widget. + * + *---------------------------------------------------------------------- + */ + +static TextStyle * +GetStyle(textPtr, indexPtr) + TkText *textPtr; /* Overall information about text widget. */ + TkTextIndex *indexPtr; /* The character in the text for which + * display information is wanted. */ +{ + TkTextTag **tagPtrs; + register TkTextTag *tagPtr; + StyleValues styleValues; + TextStyle *stylePtr; + Tcl_HashEntry *hPtr; + int numTags, new, i; + XGCValues gcValues; + unsigned long mask; + + /* + * The variables below keep track of the highest-priority specification + * that has occurred for each of the various fields of the StyleValues. + */ + + int borderPrio, borderWidthPrio, reliefPrio, bgStipplePrio; + int fgPrio, fontPrio, fgStipplePrio; + int underlinePrio, justifyPrio, offsetPrio; + int lMargin1Prio, lMargin2Prio, rMarginPrio; + int spacing1Prio, spacing2Prio, spacing3Prio; + int overstrikePrio, tabPrio, wrapPrio; + + /* + * Find out what tags are present for the character, then compute + * a StyleValues structure corresponding to those tags (scan + * through all of the tags, saving information for the highest- + * priority tag). + */ + + tagPtrs = TkBTreeGetTags(indexPtr, &numTags); + borderPrio = borderWidthPrio = reliefPrio = bgStipplePrio = -1; + fgPrio = fontPrio = fgStipplePrio = -1; + underlinePrio = justifyPrio = offsetPrio = -1; + lMargin1Prio = lMargin2Prio = rMarginPrio = -1; + spacing1Prio = spacing2Prio = spacing3Prio = -1; + overstrikePrio = tabPrio = wrapPrio = -1; + memset((VOID *) &styleValues, 0, sizeof(StyleValues)); + styleValues.relief = TK_RELIEF_FLAT; + styleValues.fgColor = textPtr->fgColor; + styleValues.tkfont = textPtr->tkfont; + styleValues.justify = TK_JUSTIFY_LEFT; + styleValues.spacing1 = textPtr->spacing1; + styleValues.spacing2 = textPtr->spacing2; + styleValues.spacing3 = textPtr->spacing3; + styleValues.tabArrayPtr = textPtr->tabArrayPtr; + styleValues.wrapMode = textPtr->wrapMode; + for (i = 0 ; i < numTags; i++) { + tagPtr = tagPtrs[i]; + + /* + * On Windows and Mac, we need to skip the selection tag if + * we don't have focus. + */ + +#ifndef ALWAYS_SHOW_SELECTION + if ((tagPtr == textPtr->selTagPtr) && !(textPtr->flags & GOT_FOCUS)) { + continue; + } +#endif + + if ((tagPtr->border != NULL) && (tagPtr->priority > borderPrio)) { + styleValues.border = tagPtr->border; + borderPrio = tagPtr->priority; + } + if ((tagPtr->bdString != NULL) + && (tagPtr->priority > borderWidthPrio)) { + styleValues.borderWidth = tagPtr->borderWidth; + borderWidthPrio = tagPtr->priority; + } + if ((tagPtr->reliefString != NULL) + && (tagPtr->priority > reliefPrio)) { + if (styleValues.border == NULL) { + styleValues.border = textPtr->border; + } + styleValues.relief = tagPtr->relief; + reliefPrio = tagPtr->priority; + } + if ((tagPtr->bgStipple != None) + && (tagPtr->priority > bgStipplePrio)) { + styleValues.bgStipple = tagPtr->bgStipple; + bgStipplePrio = tagPtr->priority; + } + if ((tagPtr->fgColor != None) && (tagPtr->priority > fgPrio)) { + styleValues.fgColor = tagPtr->fgColor; + fgPrio = tagPtr->priority; + } + if ((tagPtr->tkfont != None) && (tagPtr->priority > fontPrio)) { + styleValues.tkfont = tagPtr->tkfont; + fontPrio = tagPtr->priority; + } + if ((tagPtr->fgStipple != None) + && (tagPtr->priority > fgStipplePrio)) { + styleValues.fgStipple = tagPtr->fgStipple; + fgStipplePrio = tagPtr->priority; + } + if ((tagPtr->justifyString != NULL) + && (tagPtr->priority > justifyPrio)) { + styleValues.justify = tagPtr->justify; + justifyPrio = tagPtr->priority; + } + if ((tagPtr->lMargin1String != NULL) + && (tagPtr->priority > lMargin1Prio)) { + styleValues.lMargin1 = tagPtr->lMargin1; + lMargin1Prio = tagPtr->priority; + } + if ((tagPtr->lMargin2String != NULL) + && (tagPtr->priority > lMargin2Prio)) { + styleValues.lMargin2 = tagPtr->lMargin2; + lMargin2Prio = tagPtr->priority; + } + if ((tagPtr->offsetString != NULL) + && (tagPtr->priority > offsetPrio)) { + styleValues.offset = tagPtr->offset; + offsetPrio = tagPtr->priority; + } + if ((tagPtr->overstrikeString != NULL) + && (tagPtr->priority > overstrikePrio)) { + styleValues.overstrike = tagPtr->overstrike; + overstrikePrio = tagPtr->priority; + } + if ((tagPtr->rMarginString != NULL) + && (tagPtr->priority > rMarginPrio)) { + styleValues.rMargin = tagPtr->rMargin; + rMarginPrio = tagPtr->priority; + } + if ((tagPtr->spacing1String != NULL) + && (tagPtr->priority > spacing1Prio)) { + styleValues.spacing1 = tagPtr->spacing1; + spacing1Prio = tagPtr->priority; + } + if ((tagPtr->spacing2String != NULL) + && (tagPtr->priority > spacing2Prio)) { + styleValues.spacing2 = tagPtr->spacing2; + spacing2Prio = tagPtr->priority; + } + if ((tagPtr->spacing3String != NULL) + && (tagPtr->priority > spacing3Prio)) { + styleValues.spacing3 = tagPtr->spacing3; + spacing3Prio = tagPtr->priority; + } + if ((tagPtr->tabString != NULL) + && (tagPtr->priority > tabPrio)) { + styleValues.tabArrayPtr = tagPtr->tabArrayPtr; + tabPrio = tagPtr->priority; + } + if ((tagPtr->underlineString != NULL) + && (tagPtr->priority > underlinePrio)) { + styleValues.underline = tagPtr->underline; + underlinePrio = tagPtr->priority; + } + if ((tagPtr->wrapMode != NULL) + && (tagPtr->priority > wrapPrio)) { + styleValues.wrapMode = tagPtr->wrapMode; + wrapPrio = tagPtr->priority; + } + } + if (tagPtrs != NULL) { + ckfree((char *) tagPtrs); + } + + /* + * Use an existing style if there's one around that matches. + */ + + hPtr = Tcl_CreateHashEntry(&textPtr->dInfoPtr->styleTable, + (char *) &styleValues, &new); + if (!new) { + stylePtr = (TextStyle *) Tcl_GetHashValue(hPtr); + stylePtr->refCount++; + return stylePtr; + } + + /* + * No existing style matched. Make a new one. + */ + + stylePtr = (TextStyle *) ckalloc(sizeof(TextStyle)); + stylePtr->refCount = 1; + if (styleValues.border != NULL) { + gcValues.foreground = Tk_3DBorderColor(styleValues.border)->pixel; + mask = GCForeground; + if (styleValues.bgStipple != None) { + gcValues.stipple = styleValues.bgStipple; + gcValues.fill_style = FillStippled; + mask |= GCStipple|GCFillStyle; + } + stylePtr->bgGC = Tk_GetGC(textPtr->tkwin, mask, &gcValues); + } else { + stylePtr->bgGC = None; + } + mask = GCForeground|GCFont; + gcValues.foreground = styleValues.fgColor->pixel; + gcValues.font = Tk_FontId(styleValues.tkfont); + if (styleValues.fgStipple != None) { + gcValues.stipple = styleValues.fgStipple; + gcValues.fill_style = FillStippled; + mask |= GCStipple|GCFillStyle; + } + stylePtr->fgGC = Tk_GetGC(textPtr->tkwin, mask, &gcValues); + stylePtr->sValuePtr = (StyleValues *) + Tcl_GetHashKey(&textPtr->dInfoPtr->styleTable, hPtr); + stylePtr->hPtr = hPtr; + Tcl_SetHashValue(hPtr, stylePtr); + return stylePtr; +} + +/* + *---------------------------------------------------------------------- + * + * FreeStyle -- + * + * This procedure is called when a TextStyle structure is no longer + * needed. It decrements the reference count and frees up the + * space for the style structure if the reference count is 0. + * + * Results: + * None. + * + * Side effects: + * The storage and other resources associated with the style + * are freed up if no-one's still using it. + * + *---------------------------------------------------------------------- + */ + +static void +FreeStyle(textPtr, stylePtr) + TkText *textPtr; /* Information about overall widget. */ + register TextStyle *stylePtr; /* Information about style to free. */ + +{ + stylePtr->refCount--; + if (stylePtr->refCount == 0) { + if (stylePtr->bgGC != None) { + Tk_FreeGC(textPtr->display, stylePtr->bgGC); + } + Tk_FreeGC(textPtr->display, stylePtr->fgGC); + Tcl_DeleteHashEntry(stylePtr->hPtr); + ckfree((char *) stylePtr); + } +} + +/* + *---------------------------------------------------------------------- + * + * LayoutDLine -- + * + * This procedure generates a single DLine structure for a display + * line whose leftmost character is given by indexPtr. + * + * Results: + * The return value is a pointer to a DLine structure desribing the + * display line. All fields are filled in and correct except for + * y and nextPtr. + * + * Side effects: + * Storage is allocated for the new DLine. + * + *---------------------------------------------------------------------- + */ + +static DLine * +LayoutDLine(textPtr, indexPtr) + TkText *textPtr; /* Overall information about text widget. */ + TkTextIndex *indexPtr; /* Beginning of display line. May not + * necessarily point to a character segment. */ +{ + register DLine *dlPtr; /* New display line. */ + TkTextSegment *segPtr; /* Current segment in text. */ + TkTextDispChunk *lastChunkPtr; /* Last chunk allocated so far + * for line. */ + TkTextDispChunk *chunkPtr; /* Current chunk. */ + TkTextIndex curIndex; + TkTextDispChunk *breakChunkPtr; /* Chunk containing best word break + * point, if any. */ + TkTextIndex breakIndex; /* Index of first character in + * breakChunkPtr. */ + int breakCharOffset; /* Character within breakChunkPtr just + * to right of best break point. */ + int noCharsYet; /* Non-zero means that no characters + * have been placed on the line yet. */ + int justify; /* How to justify line: taken from + * style for first character in line. */ + int jIndent; /* Additional indentation (beyond + * margins) due to justification. */ + int rMargin; /* Right margin width for line. */ + Tk_Uid wrapMode; /* Wrap mode to use for this line. */ + int x = 0, maxX = 0; /* Initializations needed only to + * stop compiler warnings. */ + int wholeLine; /* Non-zero means this display line + * runs to the end of the text line. */ + int tabIndex; /* Index of the current tab stop. */ + int gotTab; /* Non-zero means the current chunk + * contains a tab. */ + TkTextDispChunk *tabChunkPtr; /* Pointer to the chunk containing + * the previous tab stop. */ + int maxChars; /* Maximum number of characters to + * include in this chunk. */ + TkTextTabArray *tabArrayPtr; /* Tab stops for line; taken from + * style for first character on line. */ + int tabSize; /* Number of pixels consumed by current + * tab stop. */ + TkTextDispChunk *lastCharChunkPtr; /* Pointer to last chunk in display + * lines with numChars > 0. Used to + * drop 0-sized chunks from the end + * of the line. */ + int offset, ascent, descent, code; + StyleValues *sValuePtr; + + /* + * Create and initialize a new DLine structure. + */ + + dlPtr = (DLine *) ckalloc(sizeof(DLine)); + dlPtr->index = *indexPtr; + dlPtr->count = 0; + dlPtr->y = 0; + dlPtr->oldY = -1; + dlPtr->height = 0; + dlPtr->baseline = 0; + dlPtr->chunkPtr = NULL; + dlPtr->nextPtr = NULL; + dlPtr->flags = NEW_LAYOUT; + + /* + * Each iteration of the loop below creates one TkTextDispChunk for + * the new display line. The line will always have at least one + * chunk (for the newline character at the end, if there's nothing + * else available). + */ + + curIndex = *indexPtr; + lastChunkPtr = NULL; + chunkPtr = NULL; + noCharsYet = 1; + breakChunkPtr = NULL; + breakCharOffset = 0; + justify = TK_JUSTIFY_LEFT; + tabIndex = -1; + tabChunkPtr = NULL; + tabArrayPtr = NULL; + rMargin = 0; + wrapMode = tkTextCharUid; + tabSize = 0; + lastCharChunkPtr = NULL; + + /* + * Find the first segment to consider for the line. Can't call + * TkTextIndexToSeg for this because it won't return a segment + * with zero size (such as the insertion cursor's mark). + */ + + for (offset = curIndex.charIndex, segPtr = curIndex.linePtr->segPtr; + (offset > 0) && (offset >= segPtr->size); + offset -= segPtr->size, segPtr = segPtr->nextPtr) { + /* Empty loop body. */ + } + + while (segPtr != NULL) { + if (segPtr->typePtr->layoutProc == NULL) { + segPtr = segPtr->nextPtr; + offset = 0; + continue; + } + if (chunkPtr == NULL) { + chunkPtr = (TkTextDispChunk *) ckalloc(sizeof(TkTextDispChunk)); + chunkPtr->nextPtr = NULL; + } + chunkPtr->stylePtr = GetStyle(textPtr, &curIndex); + + /* + * Save style information such as justification and indentation, + * up until the first character is encountered, then retain that + * information for the rest of the line. + */ + + if (noCharsYet) { + tabArrayPtr = chunkPtr->stylePtr->sValuePtr->tabArrayPtr; + justify = chunkPtr->stylePtr->sValuePtr->justify; + rMargin = chunkPtr->stylePtr->sValuePtr->rMargin; + wrapMode = chunkPtr->stylePtr->sValuePtr->wrapMode; + x = ((curIndex.charIndex == 0) + ? chunkPtr->stylePtr->sValuePtr->lMargin1 + : chunkPtr->stylePtr->sValuePtr->lMargin2); + if (wrapMode == tkTextNoneUid) { + maxX = INT_MAX; + } else { + maxX = textPtr->dInfoPtr->maxX - textPtr->dInfoPtr->x + - rMargin; + if (maxX < x) { + maxX = x; + } + } + } + + /* + * See if there is a tab in the current chunk; if so, only + * layout characters up to (and including) the tab. + */ + + gotTab = 0; + maxChars = segPtr->size - offset; + if (justify == TK_JUSTIFY_LEFT) { + if (segPtr->typePtr == &tkTextCharType) { + char *p; + + for (p = segPtr->body.chars + offset; *p != 0; p++) { + if (*p == '\t') { + maxChars = (p + 1 - segPtr->body.chars) - offset; + gotTab = 1; + break; + } + } + } + } + + chunkPtr->x = x; + code = (*segPtr->typePtr->layoutProc)(textPtr, &curIndex, segPtr, + offset, maxX-tabSize, maxChars, noCharsYet, wrapMode, + chunkPtr); + if (code <= 0) { + FreeStyle(textPtr, chunkPtr->stylePtr); + if (code < 0) { + /* + * This segment doesn't wish to display itself (e.g. most + * marks). + */ + + segPtr = segPtr->nextPtr; + offset = 0; + continue; + } + + /* + * No characters from this segment fit in the window: this + * means we're at the end of the display line. + */ + + if (chunkPtr != NULL) { + ckfree((char *) chunkPtr); + } + break; + } + if (chunkPtr->numChars > 0) { + noCharsYet = 0; + lastCharChunkPtr = chunkPtr; + } + if (lastChunkPtr == NULL) { + dlPtr->chunkPtr = chunkPtr; + } else { + lastChunkPtr->nextPtr = chunkPtr; + } + lastChunkPtr = chunkPtr; + x += chunkPtr->width; + if (chunkPtr->breakIndex > 0) { + breakCharOffset = chunkPtr->breakIndex; + breakIndex = curIndex; + breakChunkPtr = chunkPtr; + } + if (chunkPtr->numChars != maxChars) { + break; + } + + /* + * If we're at a new tab, adjust the layout for all the chunks + * pertaining to the previous tab. Also adjust the amount of + * space left in the line to account for space that will be eaten + * up by the tab. + */ + + if (gotTab) { + if (tabIndex >= 0) { + AdjustForTab(textPtr, tabArrayPtr, tabIndex, tabChunkPtr); + x = chunkPtr->x + chunkPtr->width; + } + tabIndex++; + tabChunkPtr = chunkPtr; + tabSize = SizeOfTab(textPtr, tabArrayPtr, tabIndex, x, maxX); + if (tabSize >= (maxX - x)) { + break; + } + } + curIndex.charIndex += chunkPtr->numChars; + offset += chunkPtr->numChars; + if (offset >= segPtr->size) { + offset = 0; + segPtr = segPtr->nextPtr; + } + chunkPtr = NULL; + } + if (noCharsYet) { + panic("LayoutDLine couldn't place any characters on a line"); + } + wholeLine = (segPtr == NULL); + + /* + * We're at the end of the display line. Throw away everything + * after the most recent word break, if there is one; this may + * potentially require the last chunk to be layed out again. + */ + + if (breakChunkPtr == NULL) { + /* + * This code makes sure that we don't accidentally display + * chunks with no characters at the end of the line (such as + * the insertion cursor). These chunks belong on the next + * line. So, throw away everything after the last chunk that + * has characters in it. + */ + + breakChunkPtr = lastCharChunkPtr; + breakCharOffset = breakChunkPtr->numChars; + } + if ((breakChunkPtr != NULL) && ((lastChunkPtr != breakChunkPtr) + || (breakCharOffset != lastChunkPtr->numChars))) { + while (1) { + chunkPtr = breakChunkPtr->nextPtr; + if (chunkPtr == NULL) { + break; + } + FreeStyle(textPtr, chunkPtr->stylePtr); + breakChunkPtr->nextPtr = chunkPtr->nextPtr; + (*chunkPtr->undisplayProc)(textPtr, chunkPtr); + ckfree((char *) chunkPtr); + } + if (breakCharOffset != breakChunkPtr->numChars) { + (*breakChunkPtr->undisplayProc)(textPtr, breakChunkPtr); + segPtr = TkTextIndexToSeg(&breakIndex, &offset); + (*segPtr->typePtr->layoutProc)(textPtr, &breakIndex, + segPtr, offset, maxX, breakCharOffset, 0, + wrapMode, breakChunkPtr); + } + lastChunkPtr = breakChunkPtr; + wholeLine = 0; + } + + /* + * Make tab adjustments for the last tab stop, if there is one. + */ + + if ((tabIndex >= 0) && (tabChunkPtr != NULL)) { + AdjustForTab(textPtr, tabArrayPtr, tabIndex, tabChunkPtr); + } + + /* + * Make one more pass over the line to recompute various things + * like its height, length, and total number of characters. Also + * modify the x-locations of chunks to reflect justification. + * If we're not wrapping, I'm not sure what is the best way to + * handle left and center justification: should the total length, + * for purposes of justification, be (a) the window width, (b) + * the length of the longest line in the window, or (c) the length + * of the longest line in the text? (c) isn't available, (b) seems + * weird, since it can change with vertical scrolling, so (a) is + * what is implemented below. + */ + + if (wrapMode == tkTextNoneUid) { + maxX = textPtr->dInfoPtr->maxX - textPtr->dInfoPtr->x - rMargin; + } + dlPtr->length = lastChunkPtr->x + lastChunkPtr->width; + if (justify == TK_JUSTIFY_LEFT) { + jIndent = 0; + } else if (justify == TK_JUSTIFY_RIGHT) { + jIndent = maxX - dlPtr->length; + } else { + jIndent = (maxX - dlPtr->length)/2; + } + ascent = descent = 0; + for (chunkPtr = dlPtr->chunkPtr; chunkPtr != NULL; + chunkPtr = chunkPtr->nextPtr) { + chunkPtr->x += jIndent; + dlPtr->count += chunkPtr->numChars; + if (chunkPtr->minAscent > ascent) { + ascent = chunkPtr->minAscent; + } + if (chunkPtr->minDescent > descent) { + descent = chunkPtr->minDescent; + } + if (chunkPtr->minHeight > dlPtr->height) { + dlPtr->height = chunkPtr->minHeight; + } + sValuePtr = chunkPtr->stylePtr->sValuePtr; + if ((sValuePtr->borderWidth > 0) + && (sValuePtr->relief != TK_RELIEF_FLAT)) { + dlPtr->flags |= HAS_3D_BORDER; + } + } + if (dlPtr->height < (ascent + descent)) { + dlPtr->height = ascent + descent; + dlPtr->baseline = ascent; + } else { + dlPtr->baseline = ascent + (dlPtr->height - ascent - descent)/2; + } + sValuePtr = dlPtr->chunkPtr->stylePtr->sValuePtr; + if (dlPtr->index.charIndex == 0) { + dlPtr->spaceAbove = sValuePtr->spacing1; + } else { + dlPtr->spaceAbove = sValuePtr->spacing2 - sValuePtr->spacing2/2; + } + if (wholeLine) { + dlPtr->spaceBelow = sValuePtr->spacing3; + } else { + dlPtr->spaceBelow = sValuePtr->spacing2/2; + } + dlPtr->height += dlPtr->spaceAbove + dlPtr->spaceBelow; + dlPtr->baseline += dlPtr->spaceAbove; + + /* + * Recompute line length: may have changed because of justification. + */ + + dlPtr->length = lastChunkPtr->x + lastChunkPtr->width; + return dlPtr; +} + +/* + *---------------------------------------------------------------------- + * + * UpdateDisplayInfo -- + * + * This procedure is invoked to recompute some or all of the + * DLine structures for a text widget. At the time it is called + * the DLine structures still left in the widget are guaranteed + * to be correct except that (a) the y-coordinates aren't + * necessarily correct, (b) there may be missing structures + * (the DLine structures get removed as soon as they are potentially + * out-of-date), and (c) DLine structures that don't start at the + * beginning of a line may be incorrect if previous information in + * the same line changed size in a way that moved a line boundary + * (DLines for any info that changed will have been deleted, but + * not DLines for unchanged info in the same text line). + * + * Results: + * None. + * + * Side effects: + * Upon return, the DLine information for textPtr correctly reflects + * the positions where characters will be displayed. However, this + * procedure doesn't actually bring the display up-to-date. + * + *---------------------------------------------------------------------- + */ + +static void +UpdateDisplayInfo(textPtr) + TkText *textPtr; /* Text widget to update. */ +{ + register TextDInfo *dInfoPtr = textPtr->dInfoPtr; + register DLine *dlPtr, *prevPtr; + TkTextIndex index; + TkTextLine *lastLinePtr; + int y, maxY, pixelOffset, maxOffset; + + if (!(dInfoPtr->flags & DINFO_OUT_OF_DATE)) { + return; + } + dInfoPtr->flags &= ~DINFO_OUT_OF_DATE; + + /* + * Delete any DLines that are now above the top of the window. + */ + + index = textPtr->topIndex; + dlPtr = FindDLine(dInfoPtr->dLinePtr, &index); + if ((dlPtr != NULL) && (dlPtr != dInfoPtr->dLinePtr)) { + FreeDLines(textPtr, dInfoPtr->dLinePtr, dlPtr, 1); + } + + /* + *-------------------------------------------------------------- + * Scan through the contents of the window from top to bottom, + * recomputing information for lines that are missing. + *-------------------------------------------------------------- + */ + + lastLinePtr = TkBTreeFindLine(textPtr->tree, + TkBTreeNumLines(textPtr->tree)); + dlPtr = dInfoPtr->dLinePtr; + prevPtr = NULL; + y = dInfoPtr->y; + maxY = dInfoPtr->maxY; + while (1) { + register DLine *newPtr; + + if (index.linePtr == lastLinePtr) { + break; + } + + /* + * There are three possibilities right now: + * (a) the next DLine (dlPtr) corresponds exactly to the next + * information we want to display: just use it as-is. + * (b) the next DLine corresponds to a different line, or to + * a segment that will be coming later in the same line: + * leave this DLine alone in the hopes that we'll be able + * to use it later, then create a new DLine in front of + * it. + * (c) the next DLine corresponds to a segment in the line we + * want, but it's a segment that has already been processed + * or will never be processed. Delete the DLine and try + * again. + * + * One other twist on all this. It's possible for 3D borders + * to interact between lines (see DisplayLineBackground) so if + * a line is relayed out and has styles with 3D borders, its + * neighbors have to be redrawn if they have 3D borders too, + * since the interactions could have changed (the neighbors + * don't have to be relayed out, just redrawn). + */ + + if ((dlPtr == NULL) || (dlPtr->index.linePtr != index.linePtr)) { + /* + * Case (b) -- must make new DLine. + */ + + makeNewDLine: + if (tkTextDebug) { + char string[TK_POS_CHARS]; + + /* + * Debugging is enabled, so keep a log of all the lines + * that were re-layed out. The test suite uses this + * information. + */ + + TkTextPrintIndex(&index, string); + Tcl_SetVar2(textPtr->interp, "tk_textRelayout", (char *) NULL, + string, + TCL_GLOBAL_ONLY|TCL_APPEND_VALUE|TCL_LIST_ELEMENT); + } + newPtr = LayoutDLine(textPtr, &index); + if (prevPtr == NULL) { + dInfoPtr->dLinePtr = newPtr; + } else { + prevPtr->nextPtr = newPtr; + if (prevPtr->flags & HAS_3D_BORDER) { + prevPtr->oldY = -1; + } + } + newPtr->nextPtr = dlPtr; + dlPtr = newPtr; + } else { + /* + * DlPtr refers to the line we want. Next check the + * index within the line. + */ + + if (index.charIndex == dlPtr->index.charIndex) { + /* + * Case (a) -- can use existing display line as-is. + */ + + if ((dlPtr->flags & HAS_3D_BORDER) && (prevPtr != NULL) + && (prevPtr->flags & (NEW_LAYOUT))) { + dlPtr->oldY = -1; + } + goto lineOK; + } + if (index.charIndex < dlPtr->index.charIndex) { + goto makeNewDLine; + } + + /* + * Case (c) -- dlPtr is useless. Discard it and start + * again with the next display line. + */ + + newPtr = dlPtr->nextPtr; + FreeDLines(textPtr, dlPtr, newPtr, 0); + dlPtr = newPtr; + if (prevPtr != NULL) { + prevPtr->nextPtr = newPtr; + } else { + dInfoPtr->dLinePtr = newPtr; + } + continue; + } + + /* + * Advance to the start of the next line. + */ + + lineOK: + dlPtr->y = y; + y += dlPtr->height; + TkTextIndexForwChars(&index, dlPtr->count, &index); + prevPtr = dlPtr; + dlPtr = dlPtr->nextPtr; + + /* + * If we switched text lines, delete any DLines left for the + * old text line. + */ + + if (index.linePtr != prevPtr->index.linePtr) { + register DLine *nextPtr; + + nextPtr = dlPtr; + while ((nextPtr != NULL) + && (nextPtr->index.linePtr == prevPtr->index.linePtr)) { + nextPtr = nextPtr->nextPtr; + } + if (nextPtr != dlPtr) { + FreeDLines(textPtr, dlPtr, nextPtr, 0); + prevPtr->nextPtr = nextPtr; + dlPtr = nextPtr; + } + } + + /* + * It's important to have the following check here rather than in + * the while statement for the loop, so that there's always at least + * one DLine generated, regardless of how small the window is. This + * keeps a lot of other code from breaking. + */ + + if (y >= maxY) { + break; + } + } + + /* + * Delete any DLine structures that don't fit on the screen. + */ + + FreeDLines(textPtr, dlPtr, (DLine *) NULL, 1); + + /* + *-------------------------------------------------------------- + * If there is extra space at the bottom of the window (because + * we've hit the end of the text), then bring in more lines at + * the top of the window, if there are any, to fill in the view. + *-------------------------------------------------------------- + */ + + if (y < maxY) { + int lineNum, spaceLeft, charsToCount; + DLine *lowestPtr; + + /* + * Layout an entire text line (potentially > 1 display line), + * then link in as many display lines as fit without moving + * the bottom line out of the window. Repeat this until + * all the extra space has been used up or we've reached the + * beginning of the text. + */ + + spaceLeft = maxY - y; + lineNum = TkBTreeLineIndex(dInfoPtr->dLinePtr->index.linePtr); + charsToCount = dInfoPtr->dLinePtr->index.charIndex; + if (charsToCount == 0) { + charsToCount = INT_MAX; + lineNum--; + } + for ( ; (lineNum >= 0) && (spaceLeft > 0); lineNum--) { + index.linePtr = TkBTreeFindLine(textPtr->tree, lineNum); + index.charIndex = 0; + lowestPtr = NULL; + do { + dlPtr = LayoutDLine(textPtr, &index); + dlPtr->nextPtr = lowestPtr; + lowestPtr = dlPtr; + TkTextIndexForwChars(&index, dlPtr->count, &index); + charsToCount -= dlPtr->count; + } while ((charsToCount > 0) + && (index.linePtr == lowestPtr->index.linePtr)); + + /* + * Scan through the display lines from the bottom one up to + * the top one. + */ + + while (lowestPtr != NULL) { + dlPtr = lowestPtr; + spaceLeft -= dlPtr->height; + if (spaceLeft < 0) { + break; + } + lowestPtr = dlPtr->nextPtr; + dlPtr->nextPtr = dInfoPtr->dLinePtr; + dInfoPtr->dLinePtr = dlPtr; + if (tkTextDebug) { + char string[TK_POS_CHARS]; + + TkTextPrintIndex(&dlPtr->index, string); + Tcl_SetVar2(textPtr->interp, "tk_textRelayout", + (char *) NULL, string, + TCL_GLOBAL_ONLY|TCL_APPEND_VALUE|TCL_LIST_ELEMENT); + } + } + FreeDLines(textPtr, lowestPtr, (DLine *) NULL, 0); + charsToCount = INT_MAX; + } + + /* + * Now we're all done except that the y-coordinates in all the + * DLines are wrong and the top index for the text is wrong. + * Update them. + */ + + textPtr->topIndex = dInfoPtr->dLinePtr->index; + y = dInfoPtr->y; + for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL; + dlPtr = dlPtr->nextPtr) { + if (y > dInfoPtr->maxY) { + panic("Added too many new lines in UpdateDisplayInfo"); + } + dlPtr->y = y; + y += dlPtr->height; + } + } + + /* + *-------------------------------------------------------------- + * If the old top or bottom line has scrolled elsewhere on the + * screen, we may not be able to re-use its old contents by + * copying bits (e.g., a beveled edge that was drawn when it was + * at the top or bottom won't be drawn when the line is in the + * middle and its neighbor has a matching background). Similarly, + * if the new top or bottom line came from somewhere else on the + * screen, we may not be able to copy the old bits. + *-------------------------------------------------------------- + */ + + dlPtr = dInfoPtr->dLinePtr; + if ((dlPtr->flags & HAS_3D_BORDER) && !(dlPtr->flags & TOP_LINE)) { + dlPtr->oldY = -1; + } + while (1) { + if ((dlPtr->flags & TOP_LINE) && (dlPtr != dInfoPtr->dLinePtr) + && (dlPtr->flags & HAS_3D_BORDER)) { + dlPtr->oldY = -1; + } + if ((dlPtr->flags & BOTTOM_LINE) && (dlPtr->nextPtr != NULL) + && (dlPtr->flags & HAS_3D_BORDER)) { + dlPtr->oldY = -1; + } + if (dlPtr->nextPtr == NULL) { + if ((dlPtr->flags & HAS_3D_BORDER) + && !(dlPtr->flags & BOTTOM_LINE)) { + dlPtr->oldY = -1; + } + dlPtr->flags &= ~TOP_LINE; + dlPtr->flags |= BOTTOM_LINE; + break; + } + dlPtr->flags &= ~(TOP_LINE|BOTTOM_LINE); + dlPtr = dlPtr->nextPtr; + } + dInfoPtr->dLinePtr->flags |= TOP_LINE; + + /* + * Arrange for scrollbars to be updated. + */ + + textPtr->flags |= UPDATE_SCROLLBARS; + + /* + *-------------------------------------------------------------- + * Deal with horizontal scrolling: + * 1. If there's empty space to the right of the longest line, + * shift the screen to the right to fill in the empty space. + * 2. If the desired horizontal scroll position has changed, + * force a full redisplay of all the lines in the widget. + * 3. If the wrap mode isn't "none" then re-scroll to the base + * position. + *-------------------------------------------------------------- + */ + + dInfoPtr->maxLength = 0; + for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL; + dlPtr = dlPtr->nextPtr) { + if (dlPtr->length > dInfoPtr->maxLength) { + dInfoPtr->maxLength = dlPtr->length; + } + } + maxOffset = (dInfoPtr->maxLength - (dInfoPtr->maxX - dInfoPtr->x) + + textPtr->charWidth - 1)/textPtr->charWidth; + if (dInfoPtr->newCharOffset > maxOffset) { + dInfoPtr->newCharOffset = maxOffset; + } + if (dInfoPtr->newCharOffset < 0) { + dInfoPtr->newCharOffset = 0; + } + pixelOffset = dInfoPtr->newCharOffset * textPtr->charWidth; + if (pixelOffset != dInfoPtr->curPixelOffset) { + dInfoPtr->curPixelOffset = pixelOffset; + for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL; + dlPtr = dlPtr->nextPtr) { + dlPtr->oldY = -1; + } + } +} + +/* + *---------------------------------------------------------------------- + * + * FreeDLines -- + * + * This procedure is called to free up all of the resources + * associated with one or more DLine structures. + * + * Results: + * None. + * + * Side effects: + * Memory gets freed and various other resources are released. + * + *---------------------------------------------------------------------- + */ + +static void +FreeDLines(textPtr, firstPtr, lastPtr, unlink) + TkText *textPtr; /* Information about overall text + * widget. */ + register DLine *firstPtr; /* Pointer to first DLine to free up. */ + DLine *lastPtr; /* Pointer to DLine just after last + * one to free (NULL means everything + * starting with firstPtr). */ + int unlink; /* 1 means DLines are currently linked + * into the list rooted at + * textPtr->dInfoPtr->dLinePtr and + * they have to be unlinked. 0 means + * just free without unlinking. */ +{ + register TkTextDispChunk *chunkPtr, *nextChunkPtr; + register DLine *nextDLinePtr; + + if (unlink) { + if (textPtr->dInfoPtr->dLinePtr == firstPtr) { + textPtr->dInfoPtr->dLinePtr = lastPtr; + } else { + register DLine *prevPtr; + for (prevPtr = textPtr->dInfoPtr->dLinePtr; + prevPtr->nextPtr != firstPtr; prevPtr = prevPtr->nextPtr) { + /* Empty loop body. */ + } + prevPtr->nextPtr = lastPtr; + } + } + while (firstPtr != lastPtr) { + nextDLinePtr = firstPtr->nextPtr; + for (chunkPtr = firstPtr->chunkPtr; chunkPtr != NULL; + chunkPtr = nextChunkPtr) { + if (chunkPtr->undisplayProc != NULL) { + (*chunkPtr->undisplayProc)(textPtr, chunkPtr); + } + FreeStyle(textPtr, chunkPtr->stylePtr); + nextChunkPtr = chunkPtr->nextPtr; + ckfree((char *) chunkPtr); + } + ckfree((char *) firstPtr); + firstPtr = nextDLinePtr; + } + textPtr->dInfoPtr->dLinesInvalidated = 1; +} + +/* + *---------------------------------------------------------------------- + * + * DisplayDLine -- + * + * This procedure is invoked to draw a single line on the + * screen. + * + * Results: + * None. + * + * Side effects: + * The line given by dlPtr is drawn at its correct position in + * textPtr's window. Note that this is one *display* line, not + * one *text* line. + * + *---------------------------------------------------------------------- + */ + +static void +DisplayDLine(textPtr, dlPtr, prevPtr, pixmap) + TkText *textPtr; /* Text widget in which to draw line. */ + register DLine *dlPtr; /* Information about line to draw. */ + DLine *prevPtr; /* Line just before one to draw, or NULL + * if dlPtr is the top line. */ + Pixmap pixmap; /* Pixmap to use for double-buffering. + * Caller must make sure it's large enough + * to hold line. */ +{ + register TkTextDispChunk *chunkPtr; + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + Display *display; + int height, x; + + /* + * First, clear the area of the line to the background color for the + * text widget. + */ + + display = Tk_Display(textPtr->tkwin); + Tk_Fill3DRectangle(textPtr->tkwin, pixmap, textPtr->border, 0, 0, + Tk_Width(textPtr->tkwin), dlPtr->height, 0, TK_RELIEF_FLAT); + + /* + * Next, draw background information for the whole line. + */ + + DisplayLineBackground(textPtr, dlPtr, prevPtr, pixmap); + + /* + * Make another pass through all of the chunks to redraw the + * insertion cursor, if it is visible on this line. Must do + * it here rather than in the foreground pass below because + * otherwise a wide insertion cursor will obscure the character + * to its left. + */ + + if (textPtr->state == tkNormalUid) { + for (chunkPtr = dlPtr->chunkPtr; (chunkPtr != NULL); + chunkPtr = chunkPtr->nextPtr) { + x = chunkPtr->x + dInfoPtr->x - dInfoPtr->curPixelOffset; + if (chunkPtr->displayProc == TkTextInsertDisplayProc) { + (*chunkPtr->displayProc)(chunkPtr, x, dlPtr->spaceAbove, + dlPtr->height - dlPtr->spaceAbove - dlPtr->spaceBelow, + dlPtr->baseline - dlPtr->spaceAbove, display, pixmap, + dlPtr->y + dlPtr->spaceAbove); + } + } + } + + /* + * Make yet another pass through all of the chunks to redraw all of + * foreground information. Note: we have to call the displayProc + * even for chunks that are off-screen. This is needed, for + * example, so that embedded windows can be unmapped in this case. + * Conve + */ + + for (chunkPtr = dlPtr->chunkPtr; (chunkPtr != NULL); + chunkPtr = chunkPtr->nextPtr) { + if (chunkPtr->displayProc == TkTextInsertDisplayProc) { + /* + * Already displayed the insertion cursor above. Don't + * do it again here. + */ + + continue; + } + x = chunkPtr->x + dInfoPtr->x - dInfoPtr->curPixelOffset; + if ((x + chunkPtr->width <= 0) || (x >= dInfoPtr->maxX)) { + /* + * Note: we have to call the displayProc even for chunks + * that are off-screen. This is needed, for example, so + * that embedded windows can be unmapped in this case. + * Display the chunk at a coordinate that can be clearly + * identified by the displayProc as being off-screen to + * the left (the displayProc may not be able to tell if + * something is off to the right). + */ + + (*chunkPtr->displayProc)(chunkPtr, -chunkPtr->width, + dlPtr->spaceAbove, + dlPtr->height - dlPtr->spaceAbove - dlPtr->spaceBelow, + dlPtr->baseline - dlPtr->spaceAbove, display, pixmap, + dlPtr->y + dlPtr->spaceAbove); + } else { + (*chunkPtr->displayProc)(chunkPtr, x, dlPtr->spaceAbove, + dlPtr->height - dlPtr->spaceAbove - dlPtr->spaceBelow, + dlPtr->baseline - dlPtr->spaceAbove, display, pixmap, + dlPtr->y + dlPtr->spaceAbove); + } + if (dInfoPtr->dLinesInvalidated) { + return; + } + } + + /* + * Copy the pixmap onto the screen. If this is the last line on + * the screen then copy a piece of the line, so that it doesn't + * overflow into the border area. Another special trick: copy the + * padding area to the left of the line; this is because the + * insertion cursor sometimes overflows onto that area and we want + * to get as much of the cursor as possible. + */ + + height = dlPtr->height; + if ((height + dlPtr->y) > dInfoPtr->maxY) { + height = dInfoPtr->maxY - dlPtr->y; + } + XCopyArea(display, pixmap, Tk_WindowId(textPtr->tkwin), dInfoPtr->copyGC, + dInfoPtr->x, 0, (unsigned) (dInfoPtr->maxX - dInfoPtr->x), + (unsigned) height, dInfoPtr->x, dlPtr->y); + linesRedrawn++; +} + +/* + *-------------------------------------------------------------- + * + * DisplayLineBackground -- + * + * This procedure is called to fill in the background for + * a display line. It draws 3D borders cleverly so that + * adjacent chunks with the same style (whether on the same + * line or different lines) have a single 3D border around + * the whole region. + * + * Results: + * There is no return value. Pixmap is filled in with background + * information for dlPtr. + * + * Side effects: + * None. + * + *-------------------------------------------------------------- + */ + +static void +DisplayLineBackground(textPtr, dlPtr, prevPtr, pixmap) + TkText *textPtr; /* Text widget containing line. */ + register DLine *dlPtr; /* Information about line to draw. */ + DLine *prevPtr; /* Line just above dlPtr, or NULL if dlPtr + * is the top-most line in the window. */ + Pixmap pixmap; /* Pixmap to use for double-buffering. + * Caller must make sure it's large enough + * to hold line. Caller must also have + * filled it with the background color for + * the widget. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + TkTextDispChunk *chunkPtr; /* Pointer to chunk in the current line. */ + TkTextDispChunk *chunkPtr2; /* Pointer to chunk in the line above or + * below the current one. NULL if we're to + * the left of or to the right of the chunks + * in the line. */ + TkTextDispChunk *nextPtr2; /* Next chunk after chunkPtr2 (it's not the + * same as chunkPtr2->nextPtr in the case + * where chunkPtr2 is NULL because the line + * is indented). */ + int leftX; /* The left edge of the region we're + * currently working on. */ + int leftXIn; /* 1 means beveled edge at leftX slopes right + * as it goes down, 0 means it slopes left + * as it goes down. */ + int rightX; /* Right edge of chunkPtr. */ + int rightX2; /* Right edge of chunkPtr2. */ + int matchLeft; /* Does the style of this line match that + * of its neighbor just to the left of + * the current x coordinate? */ + int matchRight; /* Does line's style match its neighbor + * just to the right of the current x-coord? */ + int minX, maxX, xOffset; + StyleValues *sValuePtr; + Display *display; + + /* + * Pass 1: scan through dlPtr from left to right. For each range of + * chunks with the same style, draw the main background for the style + * plus the vertical parts of the 3D borders (the left and right + * edges). + */ + + display = Tk_Display(textPtr->tkwin); + minX = dInfoPtr->curPixelOffset; + xOffset = dInfoPtr->x - minX; + maxX = minX + dInfoPtr->maxX - dInfoPtr->x; + chunkPtr = dlPtr->chunkPtr; + + /* + * Note A: in the following statement, and a few others later in + * this file marked with "See Note A above", the right side of the + * assignment was replaced with 0 on 6/18/97. This has the effect + * of highlighting the empty space to the left of a line whenever + * the leftmost character of the line is highlighted. This way, + * multi-line highlights always line up along their left edges. + * However, this may look funny in the case where a single word is + * highlighted. To undo the change, replace "leftX = 0" with "leftX + * = chunkPtr->x" and "rightX2 = 0" with "rightX2 = nextPtr2->x" + * here and at all the marked points below. This restores the old + * behavior where empty space to the left of a line is not + * highlighted, leaving a ragged left edge for multi-line + * highlights. + */ + + leftX = 0; + for (; leftX < maxX; chunkPtr = chunkPtr->nextPtr) { + if ((chunkPtr->nextPtr != NULL) + && SAME_BACKGROUND(chunkPtr->nextPtr->stylePtr, + chunkPtr->stylePtr)) { + continue; + } + sValuePtr = chunkPtr->stylePtr->sValuePtr; + rightX = chunkPtr->x + chunkPtr->width; + if ((chunkPtr->nextPtr == NULL) && (rightX < maxX)) { + rightX = maxX; + } + if (chunkPtr->stylePtr->bgGC != None) { + XFillRectangle(display, pixmap, chunkPtr->stylePtr->bgGC, + leftX + xOffset, 0, (unsigned int) (rightX - leftX), + (unsigned int) dlPtr->height); + if (sValuePtr->relief != TK_RELIEF_FLAT) { + Tk_3DVerticalBevel(textPtr->tkwin, pixmap, sValuePtr->border, + leftX + xOffset, 0, sValuePtr->borderWidth, + dlPtr->height, 1, sValuePtr->relief); + Tk_3DVerticalBevel(textPtr->tkwin, pixmap, sValuePtr->border, + rightX - sValuePtr->borderWidth + xOffset, + 0, sValuePtr->borderWidth, dlPtr->height, 0, + sValuePtr->relief); + } + } + leftX = rightX; + } + + /* + * Pass 2: draw the horizontal bevels along the top of the line. To + * do this, scan through dlPtr from left to right while simultaneously + * scanning through the line just above dlPtr. ChunkPtr2 and nextPtr2 + * refer to two adjacent chunks in the line above. + */ + + chunkPtr = dlPtr->chunkPtr; + leftX = 0; /* See Note A above. */ + leftXIn = 1; + rightX = chunkPtr->x + chunkPtr->width; + if ((chunkPtr->nextPtr == NULL) && (rightX < maxX)) { + rightX = maxX; + } + chunkPtr2 = NULL; + if (prevPtr != NULL) { + /* + * Find the chunk in the previous line that covers leftX. + */ + + nextPtr2 = prevPtr->chunkPtr; + rightX2 = 0; /* See Note A above. */ + while (rightX2 <= leftX) { + chunkPtr2 = nextPtr2; + if (chunkPtr2 == NULL) { + break; + } + nextPtr2 = chunkPtr2->nextPtr; + rightX2 = chunkPtr2->x + chunkPtr2->width; + if (nextPtr2 == NULL) { + rightX2 = INT_MAX; + } + } + } else { + nextPtr2 = NULL; + rightX2 = INT_MAX; + } + + while (leftX < maxX) { + matchLeft = (chunkPtr2 != NULL) + && SAME_BACKGROUND(chunkPtr2->stylePtr, chunkPtr->stylePtr); + sValuePtr = chunkPtr->stylePtr->sValuePtr; + if (rightX <= rightX2) { + /* + * The chunk in our line is about to end. If its style + * changes then draw the bevel for the current style. + */ + + if ((chunkPtr->nextPtr == NULL) + || !SAME_BACKGROUND(chunkPtr->stylePtr, + chunkPtr->nextPtr->stylePtr)) { + if (!matchLeft && (sValuePtr->relief != TK_RELIEF_FLAT)) { + Tk_3DHorizontalBevel(textPtr->tkwin, pixmap, + sValuePtr->border, leftX + xOffset, 0, + rightX - leftX, sValuePtr->borderWidth, leftXIn, + 1, 1, sValuePtr->relief); + } + leftX = rightX; + leftXIn = 1; + + /* + * If the chunk in the line above is also ending at + * the same point then advance to the next chunk in + * that line. + */ + + if ((rightX == rightX2) && (chunkPtr2 != NULL)) { + goto nextChunk2; + } + } + chunkPtr = chunkPtr->nextPtr; + if (chunkPtr == NULL) { + break; + } + rightX = chunkPtr->x + chunkPtr->width; + if ((chunkPtr->nextPtr == NULL) && (rightX < maxX)) { + rightX = maxX; + } + continue; + } + + /* + * The chunk in the line above is ending at an x-position where + * there is no change in the style of the current line. If the + * style above matches the current line on one side of the change + * but not on the other, we have to draw an L-shaped piece of + * bevel. + */ + + matchRight = (nextPtr2 != NULL) + && SAME_BACKGROUND(nextPtr2->stylePtr, chunkPtr->stylePtr); + if (matchLeft && !matchRight) { + if (sValuePtr->relief != TK_RELIEF_FLAT) { + Tk_3DVerticalBevel(textPtr->tkwin, pixmap, sValuePtr->border, + rightX2 - sValuePtr->borderWidth + xOffset, 0, + sValuePtr->borderWidth, sValuePtr->borderWidth, 0, + sValuePtr->relief); + } + leftX = rightX2 - sValuePtr->borderWidth; + leftXIn = 0; + } else if (!matchLeft && matchRight + && (sValuePtr->relief != TK_RELIEF_FLAT)) { + Tk_3DVerticalBevel(textPtr->tkwin, pixmap, sValuePtr->border, + rightX2 + xOffset, 0, sValuePtr->borderWidth, + sValuePtr->borderWidth, 1, sValuePtr->relief); + Tk_3DHorizontalBevel(textPtr->tkwin, pixmap, sValuePtr->border, + leftX + xOffset, 0, rightX2 + sValuePtr->borderWidth -leftX, + sValuePtr->borderWidth, leftXIn, 0, 1, + sValuePtr->relief); + } + + nextChunk2: + chunkPtr2 = nextPtr2; + if (chunkPtr2 == NULL) { + rightX2 = INT_MAX; + } else { + nextPtr2 = chunkPtr2->nextPtr; + rightX2 = chunkPtr2->x + chunkPtr2->width; + if (nextPtr2 == NULL) { + rightX2 = INT_MAX; + } + } + } + /* + * Pass 3: draw the horizontal bevels along the bottom of the line. + * This uses the same approach as pass 2. + */ + + chunkPtr = dlPtr->chunkPtr; + leftX = 0; /* See Note A above. */ + leftXIn = 0; + rightX = chunkPtr->x + chunkPtr->width; + if ((chunkPtr->nextPtr == NULL) && (rightX < maxX)) { + rightX = maxX; + } + chunkPtr2 = NULL; + if (dlPtr->nextPtr != NULL) { + /* + * Find the chunk in the previous line that covers leftX. + */ + + nextPtr2 = dlPtr->nextPtr->chunkPtr; + rightX2 = 0; /* See Note A above. */ + while (rightX2 <= leftX) { + chunkPtr2 = nextPtr2; + if (chunkPtr2 == NULL) { + break; + } + nextPtr2 = chunkPtr2->nextPtr; + rightX2 = chunkPtr2->x + chunkPtr2->width; + if (nextPtr2 == NULL) { + rightX2 = INT_MAX; + } + } + } else { + nextPtr2 = NULL; + rightX2 = INT_MAX; + } + + while (leftX < maxX) { + matchLeft = (chunkPtr2 != NULL) + && SAME_BACKGROUND(chunkPtr2->stylePtr, chunkPtr->stylePtr); + sValuePtr = chunkPtr->stylePtr->sValuePtr; + if (rightX <= rightX2) { + if ((chunkPtr->nextPtr == NULL) + || !SAME_BACKGROUND(chunkPtr->stylePtr, + chunkPtr->nextPtr->stylePtr)) { + if (!matchLeft && (sValuePtr->relief != TK_RELIEF_FLAT)) { + Tk_3DHorizontalBevel(textPtr->tkwin, pixmap, + sValuePtr->border, leftX + xOffset, + dlPtr->height - sValuePtr->borderWidth, + rightX - leftX, sValuePtr->borderWidth, leftXIn, + 0, 0, sValuePtr->relief); + } + leftX = rightX; + leftXIn = 0; + if ((rightX == rightX2) && (chunkPtr2 != NULL)) { + goto nextChunk2b; + } + } + chunkPtr = chunkPtr->nextPtr; + if (chunkPtr == NULL) { + break; + } + rightX = chunkPtr->x + chunkPtr->width; + if ((chunkPtr->nextPtr == NULL) && (rightX < maxX)) { + rightX = maxX; + } + continue; + } + + matchRight = (nextPtr2 != NULL) + && SAME_BACKGROUND(nextPtr2->stylePtr, chunkPtr->stylePtr); + if (matchLeft && !matchRight) { + if (sValuePtr->relief != TK_RELIEF_FLAT) { + Tk_3DVerticalBevel(textPtr->tkwin, pixmap, sValuePtr->border, + rightX2 - sValuePtr->borderWidth + xOffset, + dlPtr->height - sValuePtr->borderWidth, + sValuePtr->borderWidth, sValuePtr->borderWidth, 0, + sValuePtr->relief); + } + leftX = rightX2 - sValuePtr->borderWidth; + leftXIn = 1; + } else if (!matchLeft && matchRight + && (sValuePtr->relief != TK_RELIEF_FLAT)) { + Tk_3DVerticalBevel(textPtr->tkwin, pixmap, sValuePtr->border, + rightX2 + xOffset, dlPtr->height - sValuePtr->borderWidth, + sValuePtr->borderWidth, sValuePtr->borderWidth, + 1, sValuePtr->relief); + Tk_3DHorizontalBevel(textPtr->tkwin, pixmap, sValuePtr->border, + leftX + xOffset, dlPtr->height - sValuePtr->borderWidth, + rightX2 + sValuePtr->borderWidth - leftX, + sValuePtr->borderWidth, leftXIn, 1, 0, sValuePtr->relief); + } + + nextChunk2b: + chunkPtr2 = nextPtr2; + if (chunkPtr2 == NULL) { + rightX2 = INT_MAX; + } else { + nextPtr2 = chunkPtr2->nextPtr; + rightX2 = chunkPtr2->x + chunkPtr2->width; + if (nextPtr2 == NULL) { + rightX2 = INT_MAX; + } + } + } +} + +/* + *---------------------------------------------------------------------- + * + * DisplayText -- + * + * This procedure is invoked as a when-idle handler to update the + * display. It only redisplays the parts of the text widget that + * are out of date. + * + * Results: + * None. + * + * Side effects: + * Information is redrawn on the screen. + * + *---------------------------------------------------------------------- + */ + +static void +DisplayText(clientData) + ClientData clientData; /* Information about widget. */ +{ + register TkText *textPtr = (TkText *) clientData; + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + Tk_Window tkwin; + register DLine *dlPtr; + DLine *prevPtr; + Pixmap pixmap; + int maxHeight, borders; + int bottomY = 0; /* Initialization needed only to stop + * compiler warnings. */ + Tcl_Interp *interp; + + if (textPtr->tkwin == NULL) { + + /* + * The widget has been deleted. Don't do anything. + */ + + return; + } + + interp = textPtr->interp; + Tcl_Preserve((ClientData) interp); + + if (tkTextDebug) { + Tcl_SetVar2(interp, "tk_textRelayout", (char *) NULL, "", + TCL_GLOBAL_ONLY); + } + + if (textPtr->tkwin == NULL) { + + /* + * The widget has been deleted. Don't do anything. + */ + + goto end; + } + + if (!Tk_IsMapped(textPtr->tkwin) || (dInfoPtr->maxX <= dInfoPtr->x) + || (dInfoPtr->maxY <= dInfoPtr->y)) { + UpdateDisplayInfo(textPtr); + dInfoPtr->flags &= ~REDRAW_PENDING; + goto doScrollbars; + } + numRedisplays++; + if (tkTextDebug) { + Tcl_SetVar2(interp, "tk_textRedraw", (char *) NULL, "", + TCL_GLOBAL_ONLY); + } + + if (textPtr->tkwin == NULL) { + + /* + * The widget has been deleted. Don't do anything. + */ + + goto end; + } + + /* + * Choose a new current item if that is needed (this could cause + * event handlers to be invoked, hence the preserve/release calls + * and the loop, since the handlers could conceivably necessitate + * yet another current item calculation). The tkwin check is because + * the whole window could go away in the Tcl_Release call. + */ + + while (dInfoPtr->flags & REPICK_NEEDED) { + Tcl_Preserve((ClientData) textPtr); + dInfoPtr->flags &= ~REPICK_NEEDED; + TkTextPickCurrent(textPtr, &textPtr->pickEvent); + tkwin = textPtr->tkwin; + Tcl_Release((ClientData) textPtr); + if (tkwin == NULL) { + goto end; + } + } + + /* + * First recompute what's supposed to be displayed. + */ + + UpdateDisplayInfo(textPtr); + dInfoPtr->dLinesInvalidated = 0; + + /* + * See if it's possible to bring some parts of the screen up-to-date + * by scrolling (copying from other parts of the screen). + */ + + for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL; dlPtr = dlPtr->nextPtr) { + register DLine *dlPtr2; + int offset, height, y, oldY; + TkRegion damageRgn; + + if ((dlPtr->oldY == -1) || (dlPtr->y == dlPtr->oldY) + || ((dlPtr->oldY + dlPtr->height) > dInfoPtr->maxY)) { + continue; + } + + /* + * This line is already drawn somewhere in the window so it only + * needs to be copied to its new location. See if there's a group + * of lines that can all be copied together. + */ + + offset = dlPtr->y - dlPtr->oldY; + height = dlPtr->height; + y = dlPtr->y; + for (dlPtr2 = dlPtr->nextPtr; dlPtr2 != NULL; + dlPtr2 = dlPtr2->nextPtr) { + if ((dlPtr2->oldY == -1) + || ((dlPtr2->oldY + offset) != dlPtr2->y) + || ((dlPtr2->oldY + dlPtr2->height) > dInfoPtr->maxY)) { + break; + } + height += dlPtr2->height; + } + + /* + * Reduce the height of the area being copied if necessary to + * avoid overwriting the border area. + */ + + if ((y + height) > dInfoPtr->maxY) { + height = dInfoPtr->maxY -y; + } + oldY = dlPtr->oldY; + + /* + * Update the lines we are going to scroll to show that they + * have been copied. + */ + + while (1) { + dlPtr->oldY = dlPtr->y; + if (dlPtr->nextPtr == dlPtr2) { + break; + } + dlPtr = dlPtr->nextPtr; + } + + /* + * Scan through the lines following the copied ones to see if + * we are going to overwrite them with the copy operation. + * If so, mark them for redisplay. + */ + + for ( ; dlPtr2 != NULL; dlPtr2 = dlPtr2->nextPtr) { + if ((dlPtr2->oldY != -1) + && ((dlPtr2->oldY + dlPtr2->height) > y) + && (dlPtr2->oldY < (y + height))) { + dlPtr2->oldY = -1; + } + } + + /* + * Now scroll the lines. This may generate damage which we + * handle by calling TextInvalidateRegion to mark the display + * blocks as stale. + */ + + damageRgn = TkCreateRegion(); + if (TkScrollWindow(textPtr->tkwin, dInfoPtr->scrollGC, + dInfoPtr->x, oldY, + (dInfoPtr->maxX - dInfoPtr->x), height, + 0, y - oldY, damageRgn)) { + TextInvalidateRegion(textPtr, damageRgn); + } + numCopies++; + TkDestroyRegion(damageRgn); + } + + /* + * Clear the REDRAW_PENDING flag here. This is actually pretty + * tricky. We want to wait until *after* doing the scrolling, + * since that could generate more areas to redraw and don't + * want to reschedule a redisplay for them. On the other hand, + * we can't wait until after all the redisplaying, because the + * act of redisplaying could actually generate more redisplays + * (e.g. in the case of a nested window with event bindings triggered + * by redisplay). + */ + + dInfoPtr->flags &= ~REDRAW_PENDING; + + /* + * Redraw the borders if that's needed. + */ + + if (dInfoPtr->flags & REDRAW_BORDERS) { + if (tkTextDebug) { + Tcl_SetVar2(interp, "tk_textRedraw", (char *) NULL, "borders", + TCL_GLOBAL_ONLY|TCL_APPEND_VALUE|TCL_LIST_ELEMENT); + } + + if (textPtr->tkwin == NULL) { + + /* + * The widget has been deleted. Don't do anything. + */ + + goto end; + } + + Tk_Draw3DRectangle(textPtr->tkwin, Tk_WindowId(textPtr->tkwin), + textPtr->border, textPtr->highlightWidth, + textPtr->highlightWidth, + Tk_Width(textPtr->tkwin) - 2*textPtr->highlightWidth, + Tk_Height(textPtr->tkwin) - 2*textPtr->highlightWidth, + textPtr->borderWidth, textPtr->relief); + if (textPtr->highlightWidth != 0) { + GC gc; + + if (textPtr->flags & GOT_FOCUS) { + gc = Tk_GCForColor(textPtr->highlightColorPtr, + Tk_WindowId(textPtr->tkwin)); + } else { + gc = Tk_GCForColor(textPtr->highlightBgColorPtr, + Tk_WindowId(textPtr->tkwin)); + } + Tk_DrawFocusHighlight(textPtr->tkwin, gc, textPtr->highlightWidth, + Tk_WindowId(textPtr->tkwin)); + } + borders = textPtr->borderWidth + textPtr->highlightWidth; + if (textPtr->padY > 0) { + Tk_Fill3DRectangle(textPtr->tkwin, Tk_WindowId(textPtr->tkwin), + textPtr->border, borders, borders, + Tk_Width(textPtr->tkwin) - 2*borders, textPtr->padY, + 0, TK_RELIEF_FLAT); + Tk_Fill3DRectangle(textPtr->tkwin, Tk_WindowId(textPtr->tkwin), + textPtr->border, borders, + Tk_Height(textPtr->tkwin) - borders - textPtr->padY, + Tk_Width(textPtr->tkwin) - 2*borders, + textPtr->padY, 0, TK_RELIEF_FLAT); + } + if (textPtr->padX > 0) { + Tk_Fill3DRectangle(textPtr->tkwin, Tk_WindowId(textPtr->tkwin), + textPtr->border, borders, borders + textPtr->padY, + textPtr->padX, + Tk_Height(textPtr->tkwin) - 2*borders -2*textPtr->padY, + 0, TK_RELIEF_FLAT); + Tk_Fill3DRectangle(textPtr->tkwin, Tk_WindowId(textPtr->tkwin), + textPtr->border, + Tk_Width(textPtr->tkwin) - borders - textPtr->padX, + borders + textPtr->padY, textPtr->padX, + Tk_Height(textPtr->tkwin) - 2*borders -2*textPtr->padY, + 0, TK_RELIEF_FLAT); + } + dInfoPtr->flags &= ~REDRAW_BORDERS; + } + + /* + * Now we have to redraw the lines that couldn't be updated by + * scrolling. First, compute the height of the largest line and + * allocate an off-screen pixmap to use for double-buffered + * displays. + */ + + maxHeight = -1; + for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL; + dlPtr = dlPtr->nextPtr) { + if ((dlPtr->height > maxHeight) && (dlPtr->oldY != dlPtr->y)) { + maxHeight = dlPtr->height; + } + bottomY = dlPtr->y + dlPtr->height; + } + if (maxHeight > dInfoPtr->maxY) { + maxHeight = dInfoPtr->maxY; + } + if (maxHeight > 0) { + pixmap = Tk_GetPixmap(Tk_Display(textPtr->tkwin), + Tk_WindowId(textPtr->tkwin), Tk_Width(textPtr->tkwin), + maxHeight, Tk_Depth(textPtr->tkwin)); + for (prevPtr = NULL, dlPtr = textPtr->dInfoPtr->dLinePtr; + (dlPtr != NULL) && (dlPtr->y < dInfoPtr->maxY); + prevPtr = dlPtr, dlPtr = dlPtr->nextPtr) { + if (dlPtr->oldY != dlPtr->y) { + if (tkTextDebug) { + char string[TK_POS_CHARS]; + TkTextPrintIndex(&dlPtr->index, string); + Tcl_SetVar2(textPtr->interp, "tk_textRedraw", + (char *) NULL, string, + TCL_GLOBAL_ONLY|TCL_APPEND_VALUE|TCL_LIST_ELEMENT); + } + DisplayDLine(textPtr, dlPtr, prevPtr, pixmap); + if (dInfoPtr->dLinesInvalidated) { + Tk_FreePixmap(Tk_Display(textPtr->tkwin), pixmap); + return; + } + dlPtr->oldY = dlPtr->y; + dlPtr->flags &= ~NEW_LAYOUT; + } + } + Tk_FreePixmap(Tk_Display(textPtr->tkwin), pixmap); + } + + /* + * See if we need to refresh the part of the window below the + * last line of text (if there is any such area). Refresh the + * padding area on the left too, since the insertion cursor might + * have been displayed there previously). + */ + + if (dInfoPtr->topOfEof > dInfoPtr->maxY) { + dInfoPtr->topOfEof = dInfoPtr->maxY; + } + if (bottomY < dInfoPtr->topOfEof) { + if (tkTextDebug) { + Tcl_SetVar2(textPtr->interp, "tk_textRedraw", + (char *) NULL, "eof", + TCL_GLOBAL_ONLY|TCL_APPEND_VALUE|TCL_LIST_ELEMENT); + } + + if (textPtr->tkwin == NULL) { + + /* + * The widget has been deleted. Don't do anything. + */ + + goto end; + } + + Tk_Fill3DRectangle(textPtr->tkwin, Tk_WindowId(textPtr->tkwin), + textPtr->border, dInfoPtr->x - textPtr->padX, bottomY, + dInfoPtr->maxX - (dInfoPtr->x - textPtr->padX), + dInfoPtr->topOfEof-bottomY, 0, TK_RELIEF_FLAT); + } + dInfoPtr->topOfEof = bottomY; + + doScrollbars: + + /* + * Update the vertical scrollbar, if there is one. Note: it's + * important to clear REDRAW_PENDING here, just in case the + * scroll procedure does something that requires redisplay. + */ + + if (textPtr->flags & UPDATE_SCROLLBARS) { + textPtr->flags &= ~UPDATE_SCROLLBARS; + if (textPtr->yScrollCmd != NULL) { + GetYView(textPtr->interp, textPtr, 1); + } + + if (textPtr->tkwin == NULL) { + + /* + * The widget has been deleted. Don't do anything. + */ + + goto end; + } + + /* + * Update the horizontal scrollbar, if any. + */ + + if (textPtr->xScrollCmd != NULL) { + GetXView(textPtr->interp, textPtr, 1); + } + } + +end: + Tcl_Release((ClientData) interp); +} + +/* + *---------------------------------------------------------------------- + * + * TkTextEventuallyRepick -- + * + * This procedure is invoked whenever something happens that + * could change the current character or the tags associated + * with it. + * + * Results: + * None. + * + * Side effects: + * A repick is scheduled as an idle handler. + * + *---------------------------------------------------------------------- + */ + + /* ARGSUSED */ +void +TkTextEventuallyRepick(textPtr) + TkText *textPtr; /* Widget record for text widget. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + + dInfoPtr->flags |= REPICK_NEEDED; + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + dInfoPtr->flags |= REDRAW_PENDING; + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } +} + +/* + *---------------------------------------------------------------------- + * + * TkTextRedrawRegion -- + * + * This procedure is invoked to schedule a redisplay for a given + * region of a text widget. The redisplay itself may not occur + * immediately: it's scheduled as a when-idle handler. + * + * Results: + * None. + * + * Side effects: + * Information will eventually be redrawn on the screen. + * + *---------------------------------------------------------------------- + */ + + /* ARGSUSED */ +void +TkTextRedrawRegion(textPtr, x, y, width, height) + TkText *textPtr; /* Widget record for text widget. */ + int x, y; /* Coordinates of upper-left corner of area + * to be redrawn, in pixels relative to + * textPtr's window. */ + int width, height; /* Width and height of area to be redrawn. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + TkRegion damageRgn = TkCreateRegion(); + XRectangle rect; + + rect.x = x; + rect.y = y; + rect.width = width; + rect.height = height; + TkUnionRectWithRegion(&rect, damageRgn, damageRgn); + + TextInvalidateRegion(textPtr, damageRgn); + + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + dInfoPtr->flags |= REDRAW_PENDING; + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + TkDestroyRegion(damageRgn); +} + +/* + *---------------------------------------------------------------------- + * + * TextInvalidateRegion -- + * + * Mark a region of text as invalid. + * + * Results: + * None. + * + * Side effects: + * Updates the display information for the text widget. + * + *---------------------------------------------------------------------- + */ + +static void +TextInvalidateRegion(textPtr, region) + TkText *textPtr; /* Widget record for text widget. */ + TkRegion region; /* Region of area to redraw. */ +{ + register DLine *dlPtr; + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + int maxY, inset; + XRectangle rect; + + /* + * Find all lines that overlap the given region and mark them for + * redisplay. + */ + + TkClipBox(region, &rect); + maxY = rect.y + rect.height; + for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL; + dlPtr = dlPtr->nextPtr) { + if ((dlPtr->oldY != -1) && (TkRectInRegion(region, rect.x, dlPtr->y, + rect.width, (unsigned int) dlPtr->height) != RectangleOut)) { + dlPtr->oldY = -1; + } + } + if (dInfoPtr->topOfEof < maxY) { + dInfoPtr->topOfEof = maxY; + } + + /* + * Schedule the redisplay operation if there isn't one already + * scheduled. + */ + + inset = textPtr->borderWidth + textPtr->highlightWidth; + if ((rect.x < (inset + textPtr->padX)) + || (rect.y < (inset + textPtr->padY)) + || ((int) (rect.x + rect.width) > (Tk_Width(textPtr->tkwin) + - inset - textPtr->padX)) + || (maxY > (Tk_Height(textPtr->tkwin) - inset - textPtr->padY))) { + dInfoPtr->flags |= REDRAW_BORDERS; + } +} + +/* + *---------------------------------------------------------------------- + * + * TkTextChanged -- + * + * This procedure is invoked when info in a text widget is about + * to be modified in a way that changes how it is displayed (e.g. + * characters were inserted or deleted, or tag information was + * changed). This procedure must be called *before* a change is + * made, so that indexes in the display information are still + * valid. + * + * Results: + * None. + * + * Side effects: + * The range of character between index1Ptr (inclusive) and + * index2Ptr (exclusive) will be redisplayed at some point in the + * future (the actual redisplay is scheduled as a when-idle handler). + * + *---------------------------------------------------------------------- + */ + +void +TkTextChanged(textPtr, index1Ptr, index2Ptr) + TkText *textPtr; /* Widget record for text widget. */ + TkTextIndex *index1Ptr; /* Index of first character to redisplay. */ + TkTextIndex *index2Ptr; /* Index of character just after last one + * to redisplay. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + DLine *firstPtr, *lastPtr; + TkTextIndex rounded; + + /* + * Schedule both a redisplay and a recomputation of display information. + * It's done here rather than the end of the procedure for two reasons: + * + * 1. If there are no display lines to update we'll want to return + * immediately, well before the end of the procedure. + * 2. It's important to arrange for the redisplay BEFORE calling + * FreeDLines. The reason for this is subtle and has to do with + * embedded windows. The chunk delete procedure for an embedded + * window will schedule an idle handler to unmap the window. + * However, we want the idle handler for redisplay to be called + * first, so that it can put the embedded window back on the screen + * again (if appropriate). This will prevent the window from ever + * being unmapped, and thereby avoid flashing. + */ + + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + dInfoPtr->flags |= REDRAW_PENDING|DINFO_OUT_OF_DATE|REPICK_NEEDED; + + /* + * Find the DLines corresponding to index1Ptr and index2Ptr. There + * is one tricky thing here, which is that we have to relayout in + * units of whole text lines: round index1Ptr back to the beginning + * of its text line, and include all the display lines after index2, + * up to the end of its text line. This is necessary because the + * indices stored in the display lines will no longer be valid. It's + * also needed because any edit could change the way lines wrap. + */ + + rounded = *index1Ptr; + rounded.charIndex = 0; + firstPtr = FindDLine(dInfoPtr->dLinePtr, &rounded); + if (firstPtr == NULL) { + return; + } + lastPtr = FindDLine(dInfoPtr->dLinePtr, index2Ptr); + while ((lastPtr != NULL) + && (lastPtr->index.linePtr == index2Ptr->linePtr)) { + lastPtr = lastPtr->nextPtr; + } + + /* + * Delete all the DLines from firstPtr up to but not including lastPtr. + */ + + FreeDLines(textPtr, firstPtr, lastPtr, 1); +} + +/* + *---------------------------------------------------------------------- + * + * TkTextRedrawTag -- + * + * This procedure is invoked to request a redraw of all characters + * in a given range that have a particular tag on or off. It's + * called, for example, when tag options change. + * + * Results: + * None. + * + * Side effects: + * Information on the screen may be redrawn, and the layout of + * the screen may change. + * + *---------------------------------------------------------------------- + */ + +void +TkTextRedrawTag(textPtr, index1Ptr, index2Ptr, tagPtr, withTag) + TkText *textPtr; /* Widget record for text widget. */ + TkTextIndex *index1Ptr; /* First character in range to consider + * for redisplay. NULL means start at + * beginning of text. */ + TkTextIndex *index2Ptr; /* Character just after last one to consider + * for redisplay. NULL means process all + * the characters in the text. */ + TkTextTag *tagPtr; /* Information about tag. */ + int withTag; /* 1 means redraw characters that have the + * tag, 0 means redraw those without. */ +{ + register DLine *dlPtr; + DLine *endPtr; + int tagOn; + TkTextSearch search; + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + TkTextIndex *curIndexPtr; + TkTextIndex endOfText, *endIndexPtr; + + /* + * Round up the starting position if it's before the first line + * visible on the screen (we only care about what's on the screen). + */ + + dlPtr = dInfoPtr->dLinePtr; + if (dlPtr == NULL) { + return; + } + if ((index1Ptr == NULL) || (TkTextIndexCmp(&dlPtr->index, index1Ptr) > 0)) { + index1Ptr = &dlPtr->index; + } + + /* + * Set the stopping position if it wasn't specified. + */ + + if (index2Ptr == NULL) { + index2Ptr = TkTextMakeIndex(textPtr->tree, + TkBTreeNumLines(textPtr->tree), 0, &endOfText); + } + + /* + * Initialize a search through all transitions on the tag, starting + * with the first transition where the tag's current state is different + * from what it will eventually be. + */ + + TkBTreeStartSearch(index1Ptr, index2Ptr, tagPtr, &search); + /* + * Make our own curIndex because at this point search.curIndex + * may not equal index1Ptr->curIndex in the case the first tag toggle + * comes after index1Ptr (See the use of FindTagStart in TkBTreeStartSearch) + */ + curIndexPtr = index1Ptr; + tagOn = TkBTreeCharTagged(index1Ptr, tagPtr); + if (tagOn != withTag) { + if (!TkBTreeNextTag(&search)) { + return; + } + curIndexPtr = &search.curIndex; + } + + /* + * Schedule a redisplay and layout recalculation if they aren't + * already pending. This has to be done before calling FreeDLines, + * for the reason given in TkTextChanged. + */ + + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + dInfoPtr->flags |= REDRAW_PENDING|DINFO_OUT_OF_DATE|REPICK_NEEDED; + + /* + * Each loop through the loop below is for one range of characters + * where the tag's current state is different than its eventual + * state. At the top of the loop, search contains information about + * the first character in the range. + */ + + while (1) { + /* + * Find the first DLine structure in the range. Note: if the + * desired character isn't the first in its text line, then look + * for the character just before it instead. This is needed to + * handle the case where the first character of a wrapped + * display line just got smaller, so that it now fits on the + * line before: need to relayout the line containing the + * previous character. + */ + + if (curIndexPtr->charIndex == 0) { + dlPtr = FindDLine(dlPtr, curIndexPtr); + } else { + TkTextIndex tmp; + + tmp = *curIndexPtr; + tmp.charIndex -= 1; + dlPtr = FindDLine(dlPtr, &tmp); + } + if (dlPtr == NULL) { + break; + } + + /* + * Find the first DLine structure that's past the end of the range. + */ + + if (!TkBTreeNextTag(&search)) { + endIndexPtr = index2Ptr; + } else { + curIndexPtr = &search.curIndex; + endIndexPtr = curIndexPtr; + } + endPtr = FindDLine(dlPtr, endIndexPtr); + if ((endPtr != NULL) && (endPtr->index.linePtr == endIndexPtr->linePtr) + && (endPtr->index.charIndex < endIndexPtr->charIndex)) { + endPtr = endPtr->nextPtr; + } + + /* + * Delete all of the display lines in the range, so that they'll + * be re-layed out and redrawn. + */ + + FreeDLines(textPtr, dlPtr, endPtr, 1); + dlPtr = endPtr; + + /* + * Find the first text line in the next range. + */ + + if (!TkBTreeNextTag(&search)) { + break; + } + } +} + +/* + *---------------------------------------------------------------------- + * + * TkTextRelayoutWindow -- + * + * This procedure is called when something has happened that + * invalidates the whole layout of characters on the screen, such + * as a change in a configuration option for the overall text + * widget or a change in the window size. It causes all display + * information to be recomputed and the window to be redrawn. + * + * Results: + * None. + * + * Side effects: + * All the display information will be recomputed for the window + * and the window will be redrawn. + * + *---------------------------------------------------------------------- + */ + +void +TkTextRelayoutWindow(textPtr) + TkText *textPtr; /* Widget record for text widget. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + GC new; + XGCValues gcValues; + + /* + * Schedule the window redisplay. See TkTextChanged for the + * reason why this has to be done before any calls to FreeDLines. + */ + + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + dInfoPtr->flags |= REDRAW_PENDING|REDRAW_BORDERS|DINFO_OUT_OF_DATE + |REPICK_NEEDED; + + /* + * (Re-)create the graphics context for drawing the traversal + * highlight. + */ + + gcValues.graphics_exposures = False; + new = Tk_GetGC(textPtr->tkwin, GCGraphicsExposures, &gcValues); + if (dInfoPtr->copyGC != None) { + Tk_FreeGC(textPtr->display, dInfoPtr->copyGC); + } + dInfoPtr->copyGC = new; + + /* + * Throw away all the current layout information. + */ + + FreeDLines(textPtr, dInfoPtr->dLinePtr, (DLine *) NULL, 1); + dInfoPtr->dLinePtr = NULL; + + /* + * Recompute some overall things for the layout. Even if the + * window gets very small, pretend that there's at least one + * pixel of drawing space in it. + */ + + if (textPtr->highlightWidth < 0) { + textPtr->highlightWidth = 0; + } + dInfoPtr->x = textPtr->highlightWidth + textPtr->borderWidth + + textPtr->padX; + dInfoPtr->y = textPtr->highlightWidth + textPtr->borderWidth + + textPtr->padY; + dInfoPtr->maxX = Tk_Width(textPtr->tkwin) - textPtr->highlightWidth + - textPtr->borderWidth - textPtr->padX; + if (dInfoPtr->maxX <= dInfoPtr->x) { + dInfoPtr->maxX = dInfoPtr->x + 1; + } + dInfoPtr->maxY = Tk_Height(textPtr->tkwin) - textPtr->highlightWidth + - textPtr->borderWidth - textPtr->padY; + if (dInfoPtr->maxY <= dInfoPtr->y) { + dInfoPtr->maxY = dInfoPtr->y + 1; + } + dInfoPtr->topOfEof = dInfoPtr->maxY; + + /* + * If the upper-left character isn't the first in a line, recompute + * it. This is necessary because a change in the window's size + * or options could change the way lines wrap. + */ + + if (textPtr->topIndex.charIndex != 0) { + MeasureUp(textPtr, &textPtr->topIndex, 0, &textPtr->topIndex); + } + + /* + * Invalidate cached scrollbar positions, so that scrollbars + * sliders will be udpated. + */ + + dInfoPtr->xScrollFirst = dInfoPtr->xScrollLast = -1; + dInfoPtr->yScrollFirst = dInfoPtr->yScrollLast = -1; +} + +/* + *---------------------------------------------------------------------- + * + * TkTextSetYView -- + * + * This procedure is called to specify what lines are to be + * displayed in a text widget. + * + * Results: + * None. + * + * Side effects: + * The display will (eventually) be updated so that the position + * given by "indexPtr" is visible on the screen at the position + * determined by "pickPlace". + * + *---------------------------------------------------------------------- + */ + +void +TkTextSetYView(textPtr, indexPtr, pickPlace) + TkText *textPtr; /* Widget record for text widget. */ + TkTextIndex *indexPtr; /* Position that is to appear somewhere + * in the view. */ + int pickPlace; /* 0 means topLine must appear at top of + * screen. 1 means we get to pick where it + * appears: minimize screen motion or else + * display line at center of screen. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + register DLine *dlPtr; + int bottomY, close, lineIndex; + TkTextIndex tmpIndex, rounded; + Tk_FontMetrics fm; + + /* + * If the specified position is the extra line at the end of the + * text, round it back to the last real line. + */ + + lineIndex = TkBTreeLineIndex(indexPtr->linePtr); + if (lineIndex == TkBTreeNumLines(indexPtr->tree)) { + TkTextIndexBackChars(indexPtr, 1, &rounded); + indexPtr = &rounded; + } + + if (!pickPlace) { + /* + * The specified position must go at the top of the screen. + * Just leave all the DLine's alone: we may be able to reuse + * some of the information that's currently on the screen + * without redisplaying it all. + */ + + if (indexPtr->charIndex == 0) { + textPtr->topIndex = *indexPtr; + } else { + MeasureUp(textPtr, indexPtr, 0, &textPtr->topIndex); + } + goto scheduleUpdate; + } + + /* + * We have to pick where to display the index. First, bring + * the display information up to date and see if the index will be + * completely visible in the current screen configuration. If so + * then there's nothing to do. + */ + + if (dInfoPtr->flags & DINFO_OUT_OF_DATE) { + UpdateDisplayInfo(textPtr); + } + dlPtr = FindDLine(dInfoPtr->dLinePtr, indexPtr); + if (dlPtr != NULL) { + if ((dlPtr->y + dlPtr->height) > dInfoPtr->maxY) { + /* + * Part of the line hangs off the bottom of the screen; + * pretend the whole line is off-screen. + */ + + dlPtr = NULL; + } else if ((dlPtr->index.linePtr == indexPtr->linePtr) + && (dlPtr->index.charIndex <= indexPtr->charIndex)) { + return; + } + } + + /* + * The desired line isn't already on-screen. Figure out what + * it means to be "close" to the top or bottom of the screen. + * Close means within 1/3 of the screen height or within three + * lines, whichever is greater. Add one extra line also, to + * account for the way MeasureUp rounds. + */ + + Tk_GetFontMetrics(textPtr->tkfont, &fm); + bottomY = (dInfoPtr->y + dInfoPtr->maxY + fm.linespace)/2; + close = (dInfoPtr->maxY - dInfoPtr->y)/3; + if (close < 3*fm.linespace) { + close = 3*fm.linespace; + } + close += fm.linespace; + if (dlPtr != NULL) { + /* + * The desired line is above the top of screen. If it is + * "close" to the top of the window then make it the top + * line on the screen. + */ + + MeasureUp(textPtr, &textPtr->topIndex, close, &tmpIndex); + if (TkTextIndexCmp(&tmpIndex, indexPtr) <= 0) { + MeasureUp(textPtr, indexPtr, 0, &textPtr->topIndex); + goto scheduleUpdate; + } + } else { + /* + * The desired line is below the bottom of the screen. If it is + * "close" to the bottom of the screen then position it at the + * bottom of the screen. + */ + + MeasureUp(textPtr, indexPtr, close, &tmpIndex); + if (FindDLine(dInfoPtr->dLinePtr, &tmpIndex) != NULL) { + bottomY = dInfoPtr->maxY - dInfoPtr->y; + } + } + + /* + * Our job now is to arrange the display so that indexPtr appears + * as low on the screen as possible but with its bottom no lower + * than bottomY. BottomY is the bottom of the window if the + * desired line is just below the current screen, otherwise it + * is a half-line lower than the center of the window. + */ + + MeasureUp(textPtr, indexPtr, bottomY, &textPtr->topIndex); + + scheduleUpdate: + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + dInfoPtr->flags |= REDRAW_PENDING|DINFO_OUT_OF_DATE|REPICK_NEEDED; +} + +/* + *-------------------------------------------------------------- + * + * MeasureUp -- + * + * Given one index, find the index of the first character + * on the highest display line that would be displayed no more + * than "distance" pixels above the given index. + * + * Results: + * *dstPtr is filled in with the index of the first character + * on a display line. The display line is found by measuring + * up "distance" pixels above the pixel just below an imaginary + * display line that contains srcPtr. If the display line + * that covers this coordinate actually extends above the + * coordinate, then return the index of the next lower line + * instead (i.e. the returned index will be completely visible + * at or below the given y-coordinate). + * + * Side effects: + * None. + * + *-------------------------------------------------------------- + */ + +static void +MeasureUp(textPtr, srcPtr, distance, dstPtr) + TkText *textPtr; /* Text widget in which to measure. */ + TkTextIndex *srcPtr; /* Index of character from which to start + * measuring. */ + int distance; /* Vertical distance in pixels measured + * from the pixel just below the lowest + * one in srcPtr's line. */ + TkTextIndex *dstPtr; /* Index to fill in with result. */ +{ + int lineNum; /* Number of current line. */ + int charsToCount; /* Maximum number of characters to measure + * in current line. */ + TkTextIndex bestIndex; /* Best candidate seen so far for result. */ + TkTextIndex index; + DLine *dlPtr, *lowestPtr; + int noBestYet; /* 1 means bestIndex hasn't been set. */ + + noBestYet = 1; + charsToCount = srcPtr->charIndex + 1; + index.tree = srcPtr->tree; + for (lineNum = TkBTreeLineIndex(srcPtr->linePtr); lineNum >= 0; + lineNum--) { + /* + * Layout an entire text line (potentially > 1 display line). + * For the first line, which contains srcPtr, only layout the + * part up through srcPtr (charsToCount is non-infinite to + * accomplish this). Make a list of all the display lines + * in backwards order (the lowest DLine on the screen is first + * in the list). + */ + + index.linePtr = TkBTreeFindLine(srcPtr->tree, lineNum); + index.charIndex = 0; + lowestPtr = NULL; + do { + dlPtr = LayoutDLine(textPtr, &index); + dlPtr->nextPtr = lowestPtr; + lowestPtr = dlPtr; + TkTextIndexForwChars(&index, dlPtr->count, &index); + charsToCount -= dlPtr->count; + } while ((charsToCount > 0) && (index.linePtr == dlPtr->index.linePtr)); + + /* + * Scan through the display lines to see if we've covered enough + * vertical distance. If so, save the starting index for the + * line at the desired location. + */ + + for (dlPtr = lowestPtr; dlPtr != NULL; dlPtr = dlPtr->nextPtr) { + distance -= dlPtr->height; + if (distance < 0) { + *dstPtr = (noBestYet) ? dlPtr->index : bestIndex; + break; + } + bestIndex = dlPtr->index; + noBestYet = 0; + } + + /* + * Discard the display lines, then either return or prepare + * for the next display line to lay out. + */ + + FreeDLines(textPtr, lowestPtr, (DLine *) NULL, 0); + if (distance < 0) { + return; + } + charsToCount = INT_MAX; /* Consider all chars. in next line. */ + } + + /* + * Ran off the beginning of the text. Return the first character + * in the text. + */ + + TkTextMakeIndex(textPtr->tree, 0, 0, dstPtr); +} + +/* + *-------------------------------------------------------------- + * + * TkTextSeeCmd -- + * + * This procedure is invoked to process the "see" option for + * the widget command for text widgets. See the user documentation + * for details on what it does. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * See the user documentation. + * + *-------------------------------------------------------------- + */ + +int +TkTextSeeCmd(textPtr, interp, argc, argv) + TkText *textPtr; /* Information about text widget. */ + Tcl_Interp *interp; /* Current interpreter. */ + int argc; /* Number of arguments. */ + char **argv; /* Argument strings. Someone else has already + * parsed this command enough to know that + * argv[1] is "see". */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + TkTextIndex index; + int x, y, width, height, lineWidth, charCount, oneThird, delta; + DLine *dlPtr; + TkTextDispChunk *chunkPtr; + + if (argc != 3) { + Tcl_AppendResult(interp, "wrong # args: should be \"", + argv[0], " see index\"", (char *) NULL); + return TCL_ERROR; + } + if (TkTextGetIndex(interp, textPtr, argv[2], &index) != TCL_OK) { + return TCL_ERROR; + } + + /* + * If the specified position is the extra line at the end of the + * text, round it back to the last real line. + */ + + if (TkBTreeLineIndex(index.linePtr) == TkBTreeNumLines(index.tree)) { + TkTextIndexBackChars(&index, 1, &index); + } + + /* + * First get the desired position into the vertical range of the window. + */ + + TkTextSetYView(textPtr, &index, 1); + + /* + * Now make sure that the character is in view horizontally. + */ + + if (dInfoPtr->flags & DINFO_OUT_OF_DATE) { + UpdateDisplayInfo(textPtr); + } + lineWidth = dInfoPtr->maxX - dInfoPtr->x; + if (dInfoPtr->maxLength < lineWidth) { + return TCL_OK; + } + + /* + * Find the chunk that contains the desired index. + */ + + dlPtr = FindDLine(dInfoPtr->dLinePtr, &index); + charCount = index.charIndex - dlPtr->index.charIndex; + for (chunkPtr = dlPtr->chunkPtr; ; chunkPtr = chunkPtr->nextPtr) { + if (charCount < chunkPtr->numChars) { + break; + } + charCount -= chunkPtr->numChars; + } + + /* + * Call a chunk-specific procedure to find the horizontal range of + * the character within the chunk. + */ + + (*chunkPtr->bboxProc)(chunkPtr, charCount, dlPtr->y + dlPtr->spaceAbove, + dlPtr->height - dlPtr->spaceAbove - dlPtr->spaceBelow, + dlPtr->baseline - dlPtr->spaceAbove, &x, &y, &width, + &height); + delta = x - dInfoPtr->curPixelOffset; + oneThird = lineWidth/3; + if (delta < 0) { + if (delta < -oneThird) { + dInfoPtr->newCharOffset = (x - lineWidth/2)/textPtr->charWidth; + } else { + dInfoPtr->newCharOffset -= ((-delta) + textPtr->charWidth - 1) + / textPtr->charWidth; + } + } else { + delta -= (lineWidth - width); + if (delta > 0) { + if (delta > oneThird) { + dInfoPtr->newCharOffset = (x - lineWidth/2)/textPtr->charWidth; + } else { + dInfoPtr->newCharOffset += (delta + textPtr->charWidth - 1) + / textPtr->charWidth; + } + } else { + return TCL_OK; + } + } + dInfoPtr->flags |= DINFO_OUT_OF_DATE; + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + dInfoPtr->flags |= REDRAW_PENDING; + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + return TCL_OK; +} + +/* + *-------------------------------------------------------------- + * + * TkTextXviewCmd -- + * + * This procedure is invoked to process the "xview" option for + * the widget command for text widgets. See the user documentation + * for details on what it does. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * See the user documentation. + * + *-------------------------------------------------------------- + */ + +int +TkTextXviewCmd(textPtr, interp, argc, argv) + TkText *textPtr; /* Information about text widget. */ + Tcl_Interp *interp; /* Current interpreter. */ + int argc; /* Number of arguments. */ + char **argv; /* Argument strings. Someone else has already + * parsed this command enough to know that + * argv[1] is "xview". */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + int type, charsPerPage, count, newOffset; + double fraction; + + if (dInfoPtr->flags & DINFO_OUT_OF_DATE) { + UpdateDisplayInfo(textPtr); + } + + if (argc == 2) { + GetXView(interp, textPtr, 0); + return TCL_OK; + } + + newOffset = dInfoPtr->newCharOffset; + type = Tk_GetScrollInfo(interp, argc, argv, &fraction, &count); + switch (type) { + case TK_SCROLL_ERROR: + return TCL_ERROR; + case TK_SCROLL_MOVETO: + if (fraction > 1.0) { + fraction = 1.0; + } + if (fraction < 0) { + fraction = 0; + } + newOffset = (int) (((fraction * dInfoPtr->maxLength) / textPtr->charWidth) + + 0.5); + break; + case TK_SCROLL_PAGES: + charsPerPage = ((dInfoPtr->maxX - dInfoPtr->x) / textPtr->charWidth) + - 2; + if (charsPerPage < 1) { + charsPerPage = 1; + } + newOffset += charsPerPage*count; + break; + case TK_SCROLL_UNITS: + newOffset += count; + break; + } + + dInfoPtr->newCharOffset = newOffset; + dInfoPtr->flags |= DINFO_OUT_OF_DATE; + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + dInfoPtr->flags |= REDRAW_PENDING; + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + return TCL_OK; +} + +/* + *---------------------------------------------------------------------- + * + * ScrollByLines -- + * + * This procedure is called to scroll a text widget up or down + * by a given number of lines. + * + * Results: + * None. + * + * Side effects: + * The view in textPtr's window changes to reflect the value + * of "offset". + * + *---------------------------------------------------------------------- + */ + +static void +ScrollByLines(textPtr, offset) + TkText *textPtr; /* Widget to scroll. */ + int offset; /* Amount by which to scroll, in *screen* + * lines. Positive means that information + * later in text becomes visible, negative + * means that information earlier in the + * text becomes visible. */ +{ + int i, charsToCount, lineNum; + TkTextIndex new, index; + TkTextLine *lastLinePtr; + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + DLine *dlPtr, *lowestPtr; + + if (offset < 0) { + /* + * Must scroll up (to show earlier information in the text). + * The code below is similar to that in MeasureUp, except that + * it counts lines instead of pixels. + */ + + charsToCount = textPtr->topIndex.charIndex + 1; + index.tree = textPtr->tree; + offset--; /* Skip line containing topIndex. */ + for (lineNum = TkBTreeLineIndex(textPtr->topIndex.linePtr); + lineNum >= 0; lineNum--) { + index.linePtr = TkBTreeFindLine(textPtr->tree, lineNum); + index.charIndex = 0; + lowestPtr = NULL; + do { + dlPtr = LayoutDLine(textPtr, &index); + dlPtr->nextPtr = lowestPtr; + lowestPtr = dlPtr; + TkTextIndexForwChars(&index, dlPtr->count, &index); + charsToCount -= dlPtr->count; + } while ((charsToCount > 0) + && (index.linePtr == dlPtr->index.linePtr)); + + for (dlPtr = lowestPtr; dlPtr != NULL; dlPtr = dlPtr->nextPtr) { + offset++; + if (offset == 0) { + textPtr->topIndex = dlPtr->index; + break; + } + } + + /* + * Discard the display lines, then either return or prepare + * for the next display line to lay out. + */ + + FreeDLines(textPtr, lowestPtr, (DLine *) NULL, 0); + if (offset >= 0) { + goto scheduleUpdate; + } + charsToCount = INT_MAX; + } + + /* + * Ran off the beginning of the text. Return the first character + * in the text. + */ + + TkTextMakeIndex(textPtr->tree, 0, 0, &textPtr->topIndex); + } else { + /* + * Scrolling down, to show later information in the text. + * Just count lines from the current top of the window. + */ + + lastLinePtr = TkBTreeFindLine(textPtr->tree, + TkBTreeNumLines(textPtr->tree)); + for (i = 0; i < offset; i++) { + dlPtr = LayoutDLine(textPtr, &textPtr->topIndex); + dlPtr->nextPtr = NULL; + TkTextIndexForwChars(&textPtr->topIndex, dlPtr->count, &new); + FreeDLines(textPtr, dlPtr, (DLine *) NULL, 0); + if (new.linePtr == lastLinePtr) { + break; + } + textPtr->topIndex = new; + } + } + + scheduleUpdate: + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + dInfoPtr->flags |= REDRAW_PENDING|DINFO_OUT_OF_DATE|REPICK_NEEDED; +} + +/* + *-------------------------------------------------------------- + * + * TkTextYviewCmd -- + * + * This procedure is invoked to process the "yview" option for + * the widget command for text widgets. See the user documentation + * for details on what it does. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * See the user documentation. + * + *-------------------------------------------------------------- + */ + +int +TkTextYviewCmd(textPtr, interp, argc, argv) + TkText *textPtr; /* Information about text widget. */ + Tcl_Interp *interp; /* Current interpreter. */ + int argc; /* Number of arguments. */ + char **argv; /* Argument strings. Someone else has already + * parsed this command enough to know that + * argv[1] is "yview". */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + int pickPlace, lineNum, type, charsInLine; + Tk_FontMetrics fm; + int pixels, count; + size_t switchLength; + double fraction; + TkTextIndex index, new; + TkTextLine *lastLinePtr; + DLine *dlPtr; + + if (dInfoPtr->flags & DINFO_OUT_OF_DATE) { + UpdateDisplayInfo(textPtr); + } + + if (argc == 2) { + GetYView(interp, textPtr, 0); + return TCL_OK; + } + + /* + * Next, handle the old syntax: "pathName yview ?-pickplace? where" + */ + + pickPlace = 0; + if (argv[2][0] == '-') { + switchLength = strlen(argv[2]); + if ((switchLength >= 2) + && (strncmp(argv[2], "-pickplace", switchLength) == 0)) { + pickPlace = 1; + if (argc != 4) { + Tcl_AppendResult(interp, "wrong # args: should be \"", + argv[0], " yview -pickplace lineNum|index\"", + (char *) NULL); + return TCL_ERROR; + } + } + } + if ((argc == 3) || pickPlace) { + if (Tcl_GetInt(interp, argv[2+pickPlace], &lineNum) == TCL_OK) { + TkTextMakeIndex(textPtr->tree, lineNum, 0, &index); + TkTextSetYView(textPtr, &index, 0); + return TCL_OK; + } + + /* + * The argument must be a regular text index. + */ + + Tcl_ResetResult(interp); + if (TkTextGetIndex(interp, textPtr, argv[2+pickPlace], + &index) != TCL_OK) { + return TCL_ERROR; + } + TkTextSetYView(textPtr, &index, pickPlace); + return TCL_OK; + } + + /* + * New syntax: dispatch based on argv[2]. + */ + + type = Tk_GetScrollInfo(interp, argc, argv, &fraction, &count); + switch (type) { + case TK_SCROLL_ERROR: + return TCL_ERROR; + case TK_SCROLL_MOVETO: + if (fraction > 1.0) { + fraction = 1.0; + } + if (fraction < 0) { + fraction = 0; + } + fraction *= TkBTreeNumLines(textPtr->tree); + lineNum = (int) fraction; + TkTextMakeIndex(textPtr->tree, lineNum, 0, &index); + charsInLine = TkBTreeCharsInLine(index.linePtr); + index.charIndex = (int)((charsInLine * (fraction-lineNum)) + 0.5); + if (index.charIndex >= charsInLine) { + TkTextMakeIndex(textPtr->tree, lineNum+1, 0, &index); + } + TkTextSetYView(textPtr, &index, 0); + break; + case TK_SCROLL_PAGES: + /* + * Scroll up or down by screenfuls. Actually, use the + * window height minus two lines, so that there's some + * overlap between adjacent pages. + */ + + Tk_GetFontMetrics(textPtr->tkfont, &fm); + if (count < 0) { + pixels = (dInfoPtr->maxY - 2*fm.linespace - dInfoPtr->y)*(-count) + + fm.linespace; + MeasureUp(textPtr, &textPtr->topIndex, pixels, &new); + if (TkTextIndexCmp(&textPtr->topIndex, &new) == 0) { + /* + * A page of scrolling ended up being less than one line. + * Scroll one line anyway. + */ + + count = -1; + goto scrollByLines; + } + textPtr->topIndex = new; + } else { + /* + * Scrolling down by pages. Layout lines starting at the + * top index and count through the desired vertical distance. + */ + + pixels = (dInfoPtr->maxY - 2*fm.linespace - dInfoPtr->y)*count; + lastLinePtr = TkBTreeFindLine(textPtr->tree, + TkBTreeNumLines(textPtr->tree)); + do { + dlPtr = LayoutDLine(textPtr, &textPtr->topIndex); + dlPtr->nextPtr = NULL; + TkTextIndexForwChars(&textPtr->topIndex, dlPtr->count, + &new); + pixels -= dlPtr->height; + FreeDLines(textPtr, dlPtr, (DLine *) NULL, 0); + if (new.linePtr == lastLinePtr) { + break; + } + textPtr->topIndex = new; + } while (pixels > 0); + } + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + dInfoPtr->flags |= REDRAW_PENDING|DINFO_OUT_OF_DATE|REPICK_NEEDED; + break; + case TK_SCROLL_UNITS: + scrollByLines: + ScrollByLines(textPtr, count); + break; + } + return TCL_OK; +} + +/* + *-------------------------------------------------------------- + * + * TkTextScanCmd -- + * + * This procedure is invoked to process the "scan" option for + * the widget command for text widgets. See the user documentation + * for details on what it does. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * See the user documentation. + * + *-------------------------------------------------------------- + */ + +int +TkTextScanCmd(textPtr, interp, argc, argv) + register TkText *textPtr; /* Information about text widget. */ + Tcl_Interp *interp; /* Current interpreter. */ + int argc; /* Number of arguments. */ + char **argv; /* Argument strings. Someone else has already + * parsed this command enough to know that + * argv[1] is "scan". */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + TkTextIndex index; + int c, x, y, totalScroll, newChar, maxChar; + Tk_FontMetrics fm; + size_t length; + + if (argc != 5) { + Tcl_AppendResult(interp, "wrong # args: should be \"", + argv[0], " scan mark|dragto x y\"", (char *) NULL); + return TCL_ERROR; + } + if (Tcl_GetInt(interp, argv[3], &x) != TCL_OK) { + return TCL_ERROR; + } + if (Tcl_GetInt(interp, argv[4], &y) != TCL_OK) { + return TCL_ERROR; + } + c = argv[2][0]; + length = strlen(argv[2]); + if ((c == 'd') && (strncmp(argv[2], "dragto", length) == 0)) { + /* + * Amplify the difference between the current position and the + * mark position to compute how much the view should shift, then + * update the mark position to correspond to the new view. If we + * run off the edge of the text, reset the mark point so that the + * current position continues to correspond to the edge of the + * window. This means that the picture will start dragging as + * soon as the mouse reverses direction (without this reset, might + * have to slide mouse a long ways back before the picture starts + * moving again). + */ + + newChar = dInfoPtr->scanMarkChar + (10*(dInfoPtr->scanMarkX - x)) + / (textPtr->charWidth); + maxChar = 1 + (dInfoPtr->maxLength - (dInfoPtr->maxX - dInfoPtr->x) + + textPtr->charWidth - 1)/textPtr->charWidth; + if (newChar < 0) { + dInfoPtr->scanMarkChar = newChar = 0; + dInfoPtr->scanMarkX = x; + } else if (newChar > maxChar) { + dInfoPtr->scanMarkChar = newChar = maxChar; + dInfoPtr->scanMarkX = x; + } + dInfoPtr->newCharOffset = newChar; + + Tk_GetFontMetrics(textPtr->tkfont, &fm); + totalScroll = (10*(dInfoPtr->scanMarkY - y)) / fm.linespace; + if (totalScroll != dInfoPtr->scanTotalScroll) { + index = textPtr->topIndex; + ScrollByLines(textPtr, totalScroll-dInfoPtr->scanTotalScroll); + dInfoPtr->scanTotalScroll = totalScroll; + if ((index.linePtr == textPtr->topIndex.linePtr) && + (index.charIndex == textPtr->topIndex.charIndex)) { + dInfoPtr->scanTotalScroll = 0; + dInfoPtr->scanMarkY = y; + } + } + } else if ((c == 'm') && (strncmp(argv[2], "mark", length) == 0)) { + dInfoPtr->scanMarkChar = dInfoPtr->newCharOffset; + dInfoPtr->scanMarkX = x; + dInfoPtr->scanTotalScroll = 0; + dInfoPtr->scanMarkY = y; + } else { + Tcl_AppendResult(interp, "bad scan option \"", argv[2], + "\": must be mark or dragto", (char *) NULL); + return TCL_ERROR; + } + dInfoPtr->flags |= DINFO_OUT_OF_DATE; + if (!(dInfoPtr->flags & REDRAW_PENDING)) { + dInfoPtr->flags |= REDRAW_PENDING; + Tcl_DoWhenIdle(DisplayText, (ClientData) textPtr); + } + return TCL_OK; +} + +/* + *---------------------------------------------------------------------- + * + * GetXView -- + * + * This procedure computes the fractions that indicate what's + * visible in a text window and, optionally, evaluates a + * Tcl script to report them to the text's associated scrollbar. + * + * Results: + * If report is zero, then interp->result is filled in with + * two real numbers separated by a space, giving the position of + * the left and right edges of the window as fractions from 0 to + * 1, where 0 means the left edge of the text and 1 means the right + * edge. If report is non-zero, then interp->result isn't modified + * directly, but instead a script is evaluated in interp to report + * the new horizontal scroll position to the scrollbar (if the scroll + * position hasn't changed then no script is invoked). + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static void +GetXView(interp, textPtr, report) + Tcl_Interp *interp; /* If "report" is FALSE, string + * describing visible range gets + * stored in interp->result. */ + TkText *textPtr; /* Information about text widget. */ + int report; /* Non-zero means report info to + * scrollbar if it has changed. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + char buffer[200]; + double first, last; + int code; + + if (dInfoPtr->maxLength > 0) { + first = ((double) dInfoPtr->curPixelOffset) + / dInfoPtr->maxLength; + last = first + ((double) (dInfoPtr->maxX - dInfoPtr->x)) + / dInfoPtr->maxLength; + if (last > 1.0) { + last = 1.0; + } + } else { + first = 0; + last = 1.0; + } + if (!report) { + sprintf(interp->result, "%g %g", first, last); + return; + } + if ((first == dInfoPtr->xScrollFirst) && (last == dInfoPtr->xScrollLast)) { + return; + } + dInfoPtr->xScrollFirst = first; + dInfoPtr->xScrollLast = last; + sprintf(buffer, " %g %g", first, last); + code = Tcl_VarEval(interp, textPtr->xScrollCmd, + buffer, (char *) NULL); + if (code != TCL_OK) { + Tcl_AddErrorInfo(interp, + "\n (horizontal scrolling command executed by text)"); + Tcl_BackgroundError(interp); + } +} + +/* + *---------------------------------------------------------------------- + * + * GetYView -- + * + * This procedure computes the fractions that indicate what's + * visible in a text window and, optionally, evaluates a + * Tcl script to report them to the text's associated scrollbar. + * + * Results: + * If report is zero, then interp->result is filled in with + * two real numbers separated by a space, giving the position of + * the top and bottom of the window as fractions from 0 to 1, where + * 0 means the beginning of the text and 1 means the end. If + * report is non-zero, then interp->result isn't modified directly, + * but a script is evaluated in interp to report the new scroll + * position to the scrollbar (if the scroll position hasn't changed + * then no script is invoked). + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static void +GetYView(interp, textPtr, report) + Tcl_Interp *interp; /* If "report" is FALSE, string + * describing visible range gets + * stored in interp->result. */ + TkText *textPtr; /* Information about text widget. */ + int report; /* Non-zero means report info to + * scrollbar if it has changed. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + char buffer[200]; + double first, last; + DLine *dlPtr; + int totalLines, code, count; + + dlPtr = dInfoPtr->dLinePtr; + totalLines = TkBTreeNumLines(textPtr->tree); + first = ((double) TkBTreeLineIndex(dlPtr->index.linePtr)) + + ((double) dlPtr->index.charIndex) + / (TkBTreeCharsInLine(dlPtr->index.linePtr)); + first /= totalLines; + while (1) { + if ((dlPtr->y + dlPtr->height) > dInfoPtr->maxY) { + /* + * The last line is only partially visible, so don't + * count its characters in what's visible. + */ + count = 0; + break; + } + if (dlPtr->nextPtr == NULL) { + count = dlPtr->count; + break; + } + dlPtr = dlPtr->nextPtr; + } + last = ((double) TkBTreeLineIndex(dlPtr->index.linePtr)) + + ((double) (dlPtr->index.charIndex + count)) + / (TkBTreeCharsInLine(dlPtr->index.linePtr)); + last /= totalLines; + if (!report) { + sprintf(interp->result, "%g %g", first, last); + return; + } + if ((first == dInfoPtr->yScrollFirst) && (last == dInfoPtr->yScrollLast)) { + return; + } + dInfoPtr->yScrollFirst = first; + dInfoPtr->yScrollLast = last; + sprintf(buffer, " %g %g", first, last); + code = Tcl_VarEval(interp, textPtr->yScrollCmd, + buffer, (char *) NULL); + if (code != TCL_OK) { + Tcl_AddErrorInfo(interp, + "\n (vertical scrolling command executed by text)"); + Tcl_BackgroundError(interp); + } +} + +/* + *---------------------------------------------------------------------- + * + * FindDLine -- + * + * This procedure is called to find the DLine corresponding to a + * given text index. + * + * Results: + * The return value is a pointer to the first DLine found in the + * list headed by dlPtr that displays information at or after the + * specified position. If there is no such line in the list then + * NULL is returned. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static DLine * +FindDLine(dlPtr, indexPtr) + register DLine *dlPtr; /* Pointer to first in list of DLines + * to search. */ + TkTextIndex *indexPtr; /* Index of desired character. */ +{ + TkTextLine *linePtr; + + if (dlPtr == NULL) { + return NULL; + } + if (TkBTreeLineIndex(indexPtr->linePtr) + < TkBTreeLineIndex(dlPtr->index.linePtr)) { + /* + * The first display line is already past the desired line. + */ + return dlPtr; + } + + /* + * Find the first display line that covers the desired text line. + */ + + linePtr = dlPtr->index.linePtr; + while (linePtr != indexPtr->linePtr) { + while (dlPtr->index.linePtr == linePtr) { + dlPtr = dlPtr->nextPtr; + if (dlPtr == NULL) { + return NULL; + } + } + linePtr = TkBTreeNextLine(linePtr); + if (linePtr == NULL) { + panic("FindDLine reached end of text"); + } + } + if (indexPtr->linePtr != dlPtr->index.linePtr) { + return dlPtr; + } + + /* + * Now get to the right position within the text line. + */ + + while (indexPtr->charIndex >= (dlPtr->index.charIndex + dlPtr->count)) { + dlPtr = dlPtr->nextPtr; + if ((dlPtr == NULL) || (dlPtr->index.linePtr != indexPtr->linePtr)) { + break; + } + } + return dlPtr; +} + +/* + *---------------------------------------------------------------------- + * + * TkTextPixelIndex -- + * + * Given an (x,y) coordinate on the screen, find the location of + * the character closest to that location. + * + * Results: + * The index at *indexPtr is modified to refer to the character + * on the display that is closest to (x,y). + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +void +TkTextPixelIndex(textPtr, x, y, indexPtr) + TkText *textPtr; /* Widget record for text widget. */ + int x, y; /* Pixel coordinates of point in widget's + * window. */ + TkTextIndex *indexPtr; /* This index gets filled in with the + * index of the character nearest to (x,y). */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + register DLine *dlPtr; + register TkTextDispChunk *chunkPtr; + + /* + * Make sure that all of the layout information about what's + * displayed where on the screen is up-to-date. + */ + + if (dInfoPtr->flags & DINFO_OUT_OF_DATE) { + UpdateDisplayInfo(textPtr); + } + + /* + * If the coordinates are above the top of the window, then adjust + * them to refer to the upper-right corner of the window. If they're + * off to one side or the other, then adjust to the closest side. + */ + + if (y < dInfoPtr->y) { + y = dInfoPtr->y; + x = dInfoPtr->x; + } + if (x >= dInfoPtr->maxX) { + x = dInfoPtr->maxX - 1; + } + if (x < dInfoPtr->x) { + x = dInfoPtr->x; + } + + /* + * Find the display line containing the desired y-coordinate. + */ + + for (dlPtr = dInfoPtr->dLinePtr; y >= (dlPtr->y + dlPtr->height); + dlPtr = dlPtr->nextPtr) { + if (dlPtr->nextPtr == NULL) { + /* + * Y-coordinate is off the bottom of the displayed text. + * Use the last character on the last line. + */ + + x = dInfoPtr->maxX - 1; + break; + } + } + + /* + * Scan through the line's chunks to find the one that contains + * the desired x-coordinate. Before doing this, translate the + * x-coordinate from the coordinate system of the window to the + * coordinate system of the line (to take account of x-scrolling). + */ + + *indexPtr = dlPtr->index; + x = x - dInfoPtr->x + dInfoPtr->curPixelOffset; + for (chunkPtr = dlPtr->chunkPtr; x >= (chunkPtr->x + chunkPtr->width); + indexPtr->charIndex += chunkPtr->numChars, + chunkPtr = chunkPtr->nextPtr) { + if (chunkPtr->nextPtr == NULL) { + indexPtr->charIndex += chunkPtr->numChars - 1; + return; + } + } + + /* + * If the chunk has more than one character in it, ask it which + * character is at the desired location. + */ + + if (chunkPtr->numChars > 1) { + indexPtr->charIndex += (*chunkPtr->measureProc)(chunkPtr, x); + } +} + +/* + *---------------------------------------------------------------------- + * + * TkTextCharBbox -- + * + * Given an index, find the bounding box of the screen area + * occupied by that character. + * + * Results: + * Zero is returned if the character is on the screen. -1 + * means the character isn't on the screen. If the return value + * is 0, then the bounding box of the part of the character that's + * visible on the screen is returned to *xPtr, *yPtr, *widthPtr, + * and *heightPtr. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +TkTextCharBbox(textPtr, indexPtr, xPtr, yPtr, widthPtr, heightPtr) + TkText *textPtr; /* Widget record for text widget. */ + TkTextIndex *indexPtr; /* Index of character whose bounding + * box is desired. */ + int *xPtr, *yPtr; /* Filled with character's upper-left + * coordinate. */ + int *widthPtr, *heightPtr; /* Filled in with character's dimensions. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + DLine *dlPtr; + register TkTextDispChunk *chunkPtr; + int index; + + /* + * Make sure that all of the screen layout information is up to date. + */ + + if (dInfoPtr->flags & DINFO_OUT_OF_DATE) { + UpdateDisplayInfo(textPtr); + } + + /* + * Find the display line containing the desired index. + */ + + dlPtr = FindDLine(dInfoPtr->dLinePtr, indexPtr); + if ((dlPtr == NULL) || (TkTextIndexCmp(&dlPtr->index, indexPtr) > 0)) { + return -1; + } + + /* + * Find the chunk within the line that contains the desired + * index. + */ + + index = indexPtr->charIndex - dlPtr->index.charIndex; + for (chunkPtr = dlPtr->chunkPtr; ; chunkPtr = chunkPtr->nextPtr) { + if (chunkPtr == NULL) { + return -1; + } + if (index < chunkPtr->numChars) { + break; + } + index -= chunkPtr->numChars; + } + + /* + * Call a chunk-specific procedure to find the horizontal range of + * the character within the chunk, then fill in the vertical range. + * The x-coordinate returned by bboxProc is a coordinate within a + * line, not a coordinate on the screen. Translate it to reflect + * horizontal scrolling. + */ + + (*chunkPtr->bboxProc)(chunkPtr, index, dlPtr->y + dlPtr->spaceAbove, + dlPtr->height - dlPtr->spaceAbove - dlPtr->spaceBelow, + dlPtr->baseline - dlPtr->spaceAbove, xPtr, yPtr, widthPtr, + heightPtr); + *xPtr = *xPtr + dInfoPtr->x - dInfoPtr->curPixelOffset; + if ((index == (chunkPtr->numChars-1)) && (chunkPtr->nextPtr == NULL)) { + /* + * Last character in display line. Give it all the space up to + * the line. + */ + + if (*xPtr > dInfoPtr->maxX) { + *xPtr = dInfoPtr->maxX; + } + *widthPtr = dInfoPtr->maxX - *xPtr; + } + if ((*xPtr + *widthPtr) <= dInfoPtr->x) { + return -1; + } + if ((*xPtr + *widthPtr) > dInfoPtr->maxX) { + *widthPtr = dInfoPtr->maxX - *xPtr; + if (*widthPtr <= 0) { + return -1; + } + } + if ((*yPtr + *heightPtr) > dInfoPtr->maxY) { + *heightPtr = dInfoPtr->maxY - *yPtr; + if (*heightPtr <= 0) { + return -1; + } + } + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * TkTextDLineInfo -- + * + * Given an index, return information about the display line + * containing that character. + * + * Results: + * Zero is returned if the character is on the screen. -1 + * means the character isn't on the screen. If the return value + * is 0, then information is returned in the variables pointed + * to by xPtr, yPtr, widthPtr, heightPtr, and basePtr. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +TkTextDLineInfo(textPtr, indexPtr, xPtr, yPtr, widthPtr, heightPtr, basePtr) + TkText *textPtr; /* Widget record for text widget. */ + TkTextIndex *indexPtr; /* Index of character whose bounding + * box is desired. */ + int *xPtr, *yPtr; /* Filled with line's upper-left + * coordinate. */ + int *widthPtr, *heightPtr; /* Filled in with line's dimensions. */ + int *basePtr; /* Filled in with the baseline position, + * measured as an offset down from *yPtr. */ +{ + TextDInfo *dInfoPtr = textPtr->dInfoPtr; + DLine *dlPtr; + + /* + * Make sure that all of the screen layout information is up to date. + */ + + if (dInfoPtr->flags & DINFO_OUT_OF_DATE) { + UpdateDisplayInfo(textPtr); + } + + /* + * Find the display line containing the desired index. + */ + + dlPtr = FindDLine(dInfoPtr->dLinePtr, indexPtr); + if ((dlPtr == NULL) || (TkTextIndexCmp(&dlPtr->index, indexPtr) > 0)) { + return -1; + } + + *xPtr = dInfoPtr->x - dInfoPtr->curPixelOffset + dlPtr->chunkPtr->x; + *widthPtr = dlPtr->length - dlPtr->chunkPtr->x; + *yPtr = dlPtr->y; + if ((dlPtr->y + dlPtr->height) > dInfoPtr->maxY) { + *heightPtr = dInfoPtr->maxY - dlPtr->y; + } else { + *heightPtr = dlPtr->height; + } + *basePtr = dlPtr->baseline; + return 0; +} + +/* + *-------------------------------------------------------------- + * + * TkTextCharLayoutProc -- + * + * This procedure is the "layoutProc" for character segments. + * + * Results: + * If there is something to display for the chunk then a + * non-zero value is returned and the fields of chunkPtr + * will be filled in (see the declaration of TkTextDispChunk + * in tkText.h for details). If zero is returned it means + * that no characters from this chunk fit in the window. + * If -1 is returned it means that this segment just doesn't + * need to be displayed (never happens for text). + * + * Side effects: + * Memory is allocated to hold additional information about + * the chunk. + * + *-------------------------------------------------------------- + */ + +int +TkTextCharLayoutProc(textPtr, indexPtr, segPtr, offset, maxX, maxChars, + noCharsYet, wrapMode, chunkPtr) + TkText *textPtr; /* Text widget being layed out. */ + TkTextIndex *indexPtr; /* Index of first character to lay out + * (corresponds to segPtr and offset). */ + TkTextSegment *segPtr; /* Segment being layed out. */ + int offset; /* Offset within segment of first character + * to consider. */ + int maxX; /* Chunk must not occupy pixels at this + * position or higher. */ + int maxChars; /* Chunk must not include more than this + * many characters. */ + int noCharsYet; /* Non-zero means no characters have been + * assigned to this display line yet. */ + Tk_Uid wrapMode; /* How to handle line wrapping: tkTextCharUid, + * tkTextNoneUid, or tkTextWordUid. */ + register TkTextDispChunk *chunkPtr; + /* Structure to fill in with information + * about this chunk. The x field has already + * been set by the caller. */ +{ + Tk_Font tkfont; + int nextX, charsThatFit, count; + CharInfo *ciPtr; + char *p; + TkTextSegment *nextPtr; + Tk_FontMetrics fm; + + /* + * Figure out how many characters will fit in the space we've got. + * Include the next character, even though it won't fit completely, + * if any of the following is true: + * (a) the chunk contains no characters and the display line contains + * no characters yet (i.e. the line isn't wide enough to hold + * even a single character). + * (b) at least one pixel of the character is visible, we haven't + * already exceeded the character limit, and the next character + * is a white space character. + */ + + p = segPtr->body.chars + offset; + tkfont = chunkPtr->stylePtr->sValuePtr->tkfont; + charsThatFit = MeasureChars(tkfont, p, maxChars, chunkPtr->x, maxX, 0, + &nextX); + if (charsThatFit < maxChars) { + if ((charsThatFit == 0) && noCharsYet) { + charsThatFit = 1; + MeasureChars(tkfont, p, 1, chunkPtr->x, INT_MAX, 0, &nextX); + } + if ((nextX < maxX) && ((p[charsThatFit] == ' ') + || (p[charsThatFit] == '\t'))) { + /* + * Space characters are funny, in that they are considered + * to fit if there is at least one pixel of space left on the + * line. Just give the space character whatever space is left. + */ + + nextX = maxX; + charsThatFit++; + } + if (p[charsThatFit] == '\n') { + /* + * A newline character takes up no space, so if the previous + * character fits then so does the newline. + */ + + charsThatFit++; + } + if (charsThatFit == 0) { + return 0; + } + } + + Tk_GetFontMetrics(tkfont, &fm); + + /* + * Fill in the chunk structure and allocate and initialize a + * CharInfo structure. If the last character is a newline + * then don't bother to display it. + */ + + chunkPtr->displayProc = CharDisplayProc; + chunkPtr->undisplayProc = CharUndisplayProc; + chunkPtr->measureProc = CharMeasureProc; + chunkPtr->bboxProc = CharBboxProc; + chunkPtr->numChars = charsThatFit; + chunkPtr->minAscent = fm.ascent + chunkPtr->stylePtr->sValuePtr->offset; + chunkPtr->minDescent = fm.descent - chunkPtr->stylePtr->sValuePtr->offset; + chunkPtr->minHeight = 0; + chunkPtr->width = nextX - chunkPtr->x; + chunkPtr->breakIndex = -1; + ciPtr = (CharInfo *) ckalloc((unsigned) + (sizeof(CharInfo) - 3 + charsThatFit)); + chunkPtr->clientData = (ClientData) ciPtr; + ciPtr->numChars = charsThatFit; + strncpy(ciPtr->chars, p, (size_t) charsThatFit); + if (p[charsThatFit-1] == '\n') { + ciPtr->numChars--; + } + + /* + * Compute a break location. If we're in word wrap mode, a + * break can occur after any space character, or at the end of + * the chunk if the next segment (ignoring those with zero size) + * is not a character segment. + */ + + if (wrapMode != tkTextWordUid) { + chunkPtr->breakIndex = chunkPtr->numChars; + } else { + for (count = charsThatFit, p += charsThatFit-1; count > 0; + count--, p--) { + if (isspace(UCHAR(*p))) { + chunkPtr->breakIndex = count; + break; + } + } + if ((charsThatFit+offset) == segPtr->size) { + for (nextPtr = segPtr->nextPtr; nextPtr != NULL; + nextPtr = nextPtr->nextPtr) { + if (nextPtr->size != 0) { + if (nextPtr->typePtr != &tkTextCharType) { + chunkPtr->breakIndex = chunkPtr->numChars; + } + break; + } + } + } + } + return 1; +} + +/* + *-------------------------------------------------------------- + * + * CharDisplayProc -- + * + * This procedure is called to display a character chunk on + * the screen or in an off-screen pixmap. + * + * Results: + * None. + * + * Side effects: + * Graphics are drawn. + * + *-------------------------------------------------------------- + */ + +static void +CharDisplayProc(chunkPtr, x, y, height, baseline, display, dst, screenY) + TkTextDispChunk *chunkPtr; /* Chunk that is to be drawn. */ + int x; /* X-position in dst at which to + * draw this chunk (may differ from + * the x-position in the chunk because + * of scrolling). */ + int y; /* Y-position at which to draw this + * chunk in dst. */ + int height; /* Total height of line. */ + int baseline; /* Offset of baseline from y. */ + Display *display; /* Display to use for drawing. */ + Drawable dst; /* Pixmap or window in which to draw + * chunk. */ + int screenY; /* Y-coordinate in text window that + * corresponds to y. */ +{ + CharInfo *ciPtr = (CharInfo *) chunkPtr->clientData; + TextStyle *stylePtr; + StyleValues *sValuePtr; + int offsetChars, offsetX; + + if ((x + chunkPtr->width) <= 0) { + /* + * The chunk is off-screen. + */ + + return; + } + + stylePtr = chunkPtr->stylePtr; + sValuePtr = stylePtr->sValuePtr; + + /* + * If the text sticks out way to the left of the window, skip + * over the characters that aren't in the visible part of the + * window. This is essential if x is very negative (such as + * less than 32K); otherwise overflow problems will occur + * in servers that use 16-bit arithmetic, like X. + */ + + offsetX = x; + offsetChars = 0; + if (x < 0) { + offsetChars = MeasureChars(sValuePtr->tkfont, ciPtr->chars, + ciPtr->numChars, x, 0, x - chunkPtr->x, &offsetX); + } + + /* + * Draw the text, underline, and overstrike for this chunk. + */ + + if (ciPtr->numChars > offsetChars) { + int numChars = ciPtr->numChars - offsetChars; + char *string = ciPtr->chars + offsetChars; + + if ((numChars > 0) && (string[numChars - 1] == '\t')) { + numChars--; + } + Tk_DrawChars(display, dst, stylePtr->fgGC, sValuePtr->tkfont, string, + numChars, offsetX, y + baseline - sValuePtr->offset); + if (sValuePtr->underline) { + Tk_UnderlineChars(display, dst, stylePtr->fgGC, sValuePtr->tkfont, + ciPtr->chars + offsetChars, offsetX, + y + baseline - sValuePtr->offset, + 0, numChars); + + } + if (sValuePtr->overstrike) { + Tk_FontMetrics fm; + + Tk_GetFontMetrics(sValuePtr->tkfont, &fm); + Tk_UnderlineChars(display, dst, stylePtr->fgGC, sValuePtr->tkfont, + ciPtr->chars + offsetChars, offsetX, + y + baseline - sValuePtr->offset + - fm.descent - (fm.ascent * 3) / 10, + 0, numChars); + } + } +} + +/* + *-------------------------------------------------------------- + * + * CharUndisplayProc -- + * + * This procedure is called when a character chunk is no + * longer going to be displayed. It frees up resources + * that were allocated to display the chunk. + * + * Results: + * None. + * + * Side effects: + * Memory and other resources get freed. + * + *-------------------------------------------------------------- + */ + +static void +CharUndisplayProc(textPtr, chunkPtr) + TkText *textPtr; /* Overall information about text + * widget. */ + TkTextDispChunk *chunkPtr; /* Chunk that is about to be freed. */ +{ + CharInfo *ciPtr = (CharInfo *) chunkPtr->clientData; + + ckfree((char *) ciPtr); +} + +/* + *-------------------------------------------------------------- + * + * CharMeasureProc -- + * + * This procedure is called to determine which character in + * a character chunk lies over a given x-coordinate. + * + * Results: + * The return value is the index *within the chunk* of the + * character that covers the position given by "x". + * + * Side effects: + * None. + * + *-------------------------------------------------------------- + */ + +static int +CharMeasureProc(chunkPtr, x) + TkTextDispChunk *chunkPtr; /* Chunk containing desired coord. */ + int x; /* X-coordinate, in same coordinate + * system as chunkPtr->x. */ +{ + CharInfo *ciPtr = (CharInfo *) chunkPtr->clientData; + int endX; + + return MeasureChars(chunkPtr->stylePtr->sValuePtr->tkfont, ciPtr->chars, + chunkPtr->numChars-1, chunkPtr->x, x, 0, &endX); +} + +/* + *-------------------------------------------------------------- + * + * CharBboxProc -- + * + * This procedure is called to compute the bounding box of + * the area occupied by a single character. + * + * Results: + * There is no return value. *xPtr and *yPtr are filled in + * with the coordinates of the upper left corner of the + * character, and *widthPtr and *heightPtr are filled in with + * the dimensions of the character in pixels. Note: not all + * of the returned bbox is necessarily visible on the screen + * (the rightmost part might be off-screen to the right, + * and the bottommost part might be off-screen to the bottom). + * + * Side effects: + * None. + * + *-------------------------------------------------------------- + */ + +static void +CharBboxProc(chunkPtr, index, y, lineHeight, baseline, xPtr, yPtr, + widthPtr, heightPtr) + TkTextDispChunk *chunkPtr; /* Chunk containing desired char. */ + int index; /* Index of desired character within + * the chunk. */ + int y; /* Topmost pixel in area allocated + * for this line. */ + int lineHeight; /* Height of line, in pixels. */ + int baseline; /* Location of line's baseline, in + * pixels measured down from y. */ + int *xPtr, *yPtr; /* Gets filled in with coords of + * character's upper-left pixel. + * X-coord is in same coordinate + * system as chunkPtr->x. */ + int *widthPtr; /* Gets filled in with width of + * character, in pixels. */ + int *heightPtr; /* Gets filled in with height of + * character, in pixels. */ +{ + CharInfo *ciPtr = (CharInfo *) chunkPtr->clientData; + int maxX; + + maxX = chunkPtr->width + chunkPtr->x; + MeasureChars(chunkPtr->stylePtr->sValuePtr->tkfont, ciPtr->chars, index, + chunkPtr->x, 1000000, 0, xPtr); + + if (index == ciPtr->numChars) { + /* + * This situation only happens if the last character in a line + * is a space character, in which case it absorbs all of the + * extra space in the line (see TkTextCharLayoutProc). + */ + + *widthPtr = maxX - *xPtr; + } else if ((ciPtr->chars[index] == '\t') + && (index == (ciPtr->numChars-1))) { + /* + * The desired character is a tab character that terminates a + * chunk; give it all the space left in the chunk. + */ + + *widthPtr = maxX - *xPtr; + } else { + MeasureChars(chunkPtr->stylePtr->sValuePtr->tkfont, + ciPtr->chars + index, 1, *xPtr, 1000000, 0, widthPtr); + if (*widthPtr > maxX) { + *widthPtr = maxX - *xPtr; + } else { + *widthPtr -= *xPtr; + } + } + *yPtr = y + baseline - chunkPtr->minAscent; + *heightPtr = chunkPtr->minAscent + chunkPtr->minDescent; +} + +/* + *---------------------------------------------------------------------- + * + * AdjustForTab -- + * + * This procedure is called to move a series of chunks right + * in order to align them with a tab stop. + * + * Results: + * None. + * + * Side effects: + * The width of chunkPtr gets adjusted so that it absorbs the + * extra space due to the tab. The x locations in all the chunks + * after chunkPtr are adjusted rightward to align with the tab + * stop given by tabArrayPtr and index. + * + *---------------------------------------------------------------------- + */ + +static void +AdjustForTab(textPtr, tabArrayPtr, index, chunkPtr) + TkText *textPtr; /* Information about the text widget as + * a whole. */ + TkTextTabArray *tabArrayPtr; /* Information about the tab stops + * that apply to this line. May be + * NULL to indicate default tabbing + * (every 8 chars). */ + int index; /* Index of current tab stop. */ + TkTextDispChunk *chunkPtr; /* Chunk whose last character is + * the tab; the following chunks + * contain information to be shifted + * right. */ + +{ + int x, desired, delta, width, decimal, i, gotDigit; + TkTextDispChunk *chunkPtr2, *decimalChunkPtr; + CharInfo *ciPtr; + int tabX, prev, spaceWidth; + char *p; + TkTextTabAlign alignment; + + if (chunkPtr->nextPtr == NULL) { + /* + * Nothing after the actual tab; just return. + */ + + return; + } + + /* + * If no tab information has been given, do the usual thing: + * round up to the next boundary of 8 average-sized characters. + */ + + x = chunkPtr->nextPtr->x; + if ((tabArrayPtr == NULL) || (tabArrayPtr->numTabs == 0)) { + /* + * No tab information has been given, so use the default + * interpretation of tabs. + */ + + desired = NextTabStop(textPtr->tkfont, x, 0); + goto update; + } + + if (index < tabArrayPtr->numTabs) { + alignment = tabArrayPtr->tabs[index].alignment; + tabX = tabArrayPtr->tabs[index].location; + } else { + /* + * Ran out of tab stops; compute a tab position by extrapolating + * from the last two tab positions. + */ + + if (tabArrayPtr->numTabs > 1) { + prev = tabArrayPtr->tabs[tabArrayPtr->numTabs-2].location; + } else { + prev = 0; + } + alignment = tabArrayPtr->tabs[tabArrayPtr->numTabs-1].alignment; + tabX = tabArrayPtr->tabs[tabArrayPtr->numTabs-1].location + + (index + 1 - tabArrayPtr->numTabs) + * (tabArrayPtr->tabs[tabArrayPtr->numTabs-1].location - prev); + } + + if (alignment == LEFT) { + desired = tabX; + goto update; + } + + if ((alignment == CENTER) || (alignment == RIGHT)) { + /* + * Compute the width of all the information in the tab group, + * then use it to pick a desired location. + */ + + width = 0; + for (chunkPtr2 = chunkPtr->nextPtr; chunkPtr2 != NULL; + chunkPtr2 = chunkPtr2->nextPtr) { + width += chunkPtr2->width; + } + if (alignment == CENTER) { + desired = tabX - width/2; + } else { + desired = tabX - width; + } + goto update; + } + + /* + * Must be numeric alignment. Search through the text to be + * tabbed, looking for the last , or . before the first character + * that isn't a number, comma, period, or sign. + */ + + decimalChunkPtr = NULL; + decimal = gotDigit = 0; + for (chunkPtr2 = chunkPtr->nextPtr; chunkPtr2 != NULL; + chunkPtr2 = chunkPtr2->nextPtr) { + if (chunkPtr2->displayProc != CharDisplayProc) { + continue; + } + ciPtr = (CharInfo *) chunkPtr2->clientData; + for (p = ciPtr->chars, i = 0; i < ciPtr->numChars; p++, i++) { + if (isdigit(UCHAR(*p))) { + gotDigit = 1; + } else if ((*p == '.') || (*p == ',')) { + decimal = p-ciPtr->chars; + decimalChunkPtr = chunkPtr2; + } else if (gotDigit) { + if (decimalChunkPtr == NULL) { + decimal = p-ciPtr->chars; + decimalChunkPtr = chunkPtr2; + } + goto endOfNumber; + } + } + } + endOfNumber: + if (decimalChunkPtr != NULL) { + int curX; + + ciPtr = (CharInfo *) decimalChunkPtr->clientData; + MeasureChars(decimalChunkPtr->stylePtr->sValuePtr->tkfont, + ciPtr->chars, decimal, decimalChunkPtr->x, 1000000, 0, &curX); + desired = tabX - (curX - x); + goto update; + } else { + /* + * There wasn't a decimal point. Right justify the text. + */ + + width = 0; + for (chunkPtr2 = chunkPtr->nextPtr; chunkPtr2 != NULL; + chunkPtr2 = chunkPtr2->nextPtr) { + width += chunkPtr2->width; + } + desired = tabX - width; + } + + /* + * Shift all of the chunks to the right so that the left edge is + * at the desired location, then expand the chunk containing the + * tab. Be sure that the tab occupies at least the width of a + * space character. + */ + + update: + delta = desired - x; + MeasureChars(textPtr->tkfont, " ", 1, 0, INT_MAX, 0, &spaceWidth); + if (delta < spaceWidth) { + delta = spaceWidth; + } + for (chunkPtr2 = chunkPtr->nextPtr; chunkPtr2 != NULL; + chunkPtr2 = chunkPtr2->nextPtr) { + chunkPtr2->x += delta; + } + chunkPtr->width += delta; +} + +/* + *---------------------------------------------------------------------- + * + * SizeOfTab -- + * + * This returns an estimate of the amount of white space that will + * be consumed by a tab. + * + * Results: + * The return value is the minimum number of pixels that will + * be occupied by the index'th tab of tabArrayPtr, assuming that + * the current position on the line is x and the end of the + * line is maxX. For numeric tabs, this is a conservative + * estimate. The return value is always >= 0. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static int +SizeOfTab(textPtr, tabArrayPtr, index, x, maxX) + TkText *textPtr; /* Information about the text widget as + * a whole. */ + TkTextTabArray *tabArrayPtr; /* Information about the tab stops + * that apply to this line. NULL + * means use default tabbing (every + * 8 chars.) */ + int index; /* Index of current tab stop. */ + int x; /* Current x-location in line. Only + * used if tabArrayPtr == NULL. */ + int maxX; /* X-location of pixel just past the + * right edge of the line. */ +{ + int tabX, prev, result, spaceWidth; + TkTextTabAlign alignment; + + if ((tabArrayPtr == NULL) || (tabArrayPtr->numTabs == 0)) { + tabX = NextTabStop(textPtr->tkfont, x, 0); + return tabX - x; + } + if (index < tabArrayPtr->numTabs) { + tabX = tabArrayPtr->tabs[index].location; + alignment = tabArrayPtr->tabs[index].alignment; + } else { + /* + * Ran out of tab stops; compute a tab position by extrapolating + * from the last two tab positions. + */ + + if (tabArrayPtr->numTabs > 1) { + prev = tabArrayPtr->tabs[tabArrayPtr->numTabs-2].location; + } else { + prev = 0; + } + tabX = tabArrayPtr->tabs[tabArrayPtr->numTabs-1].location + + (index + 1 - tabArrayPtr->numTabs) + * (tabArrayPtr->tabs[tabArrayPtr->numTabs-1].location - prev); + alignment = tabArrayPtr->tabs[tabArrayPtr->numTabs-1].alignment; + } + if (alignment == CENTER) { + /* + * Be very careful in the arithmetic below, because maxX may + * be the largest positive number: watch out for integer + * overflow. + */ + + if ((maxX-tabX) < (tabX - x)) { + result = (maxX - x) - 2*(maxX - tabX); + } else { + result = 0; + } + goto done; + } + if (alignment == RIGHT) { + result = 0; + goto done; + } + + /* + * Note: this treats NUMERIC alignment the same as LEFT + * alignment, which is somewhat conservative. However, it's + * pretty tricky at this point to figure out exactly where + * the damn decimal point will be. + */ + + if (tabX > x) { + result = tabX - x; + } else { + result = 0; + } + + done: + MeasureChars(textPtr->tkfont, " ", 1, 0, INT_MAX, 0, &spaceWidth); + if (result < spaceWidth) { + result = spaceWidth; + } + return result; +} + +/* + *--------------------------------------------------------------------------- + * + * NextTabStop -- + * + * Given the current position, determine where the next default + * tab stop would be located. This procedure is called when the + * current chunk in the text has no tabs defined and so the default + * tab spacing for the font should be used. + * + * Results: + * The location in pixels of the next tab stop. + * + * Side effects: + * None. + * + *--------------------------------------------------------------------------- + */ + +static int +NextTabStop(tkfont, x, tabOrigin) + Tk_Font tkfont; /* Font in which chunk that contains tab + * stop will be drawn. */ + int x; /* X-position in pixels where last + * character was drawn. The next tab stop + * occurs somewhere after this location. */ + int tabOrigin; /* The origin for tab stops. May be + * non-zero if text has been scrolled. */ +{ + int tabWidth, rem; + + tabWidth = Tk_TextWidth(tkfont, "0", 1) * 8; + if (tabWidth == 0) { + tabWidth = 1; + } + + x += tabWidth; + rem = (x - tabOrigin) % tabWidth; + if (rem < 0) { + rem += tabWidth; + } + x -= rem; + return x; +} + +/* + *--------------------------------------------------------------------------- + * + * MeasureChars -- + * + * Determine the number of characters from the string that will fit + * in the given horizontal span. The measurement is done under the + * assumption that Tk_DisplayChars will be used to actually display + * the characters. + * + * If tabs are encountered in the string, they will be expanded + * to the next tab stop, unless the TK_IGNORE_TABS flag is specified. + * + * If a newline is encountered in the string, the line will be + * broken at that point, unless the TK_NEWSLINES_NOT_SPECIAL flag + * is specified. + * + * Results: + * The return value is the number of characters from source + * that fit in the span given by startX and maxX. *nextXPtr + * is filled in with the x-coordinate at which the first + * character that didn't fit would be drawn, if it were to + * be drawn. + * + * Side effects: + * None. + * + *-------------------------------------------------------------- + */ + +static int +MeasureChars(tkfont, source, maxChars, startX, maxX, tabOrigin, nextXPtr) + Tk_Font tkfont; /* Font in which to draw characters. */ + CONST char *source; /* Characters to be displayed. Need not + * be NULL-terminated. */ + int maxChars; /* Maximum # of characters to consider from + * source. */ + int startX; /* X-position at which first character will + * be drawn. */ + int maxX; /* Don't consider any character that would + * cross this x-position. */ + int tabOrigin; /* X-location that serves as "origin" for + * tab stops. */ + int *nextXPtr; /* Return x-position of terminating + * character here. */ +{ + int curX, width, ch; + CONST char *special, *end, *start; + + ch = 0; /* lint. */ + curX = startX; + special = source; + end = source + maxChars; + for (start = source; start < end; ) { + if (start >= special) { + /* + * Find the next special character in the string. + */ + + for (special = start; special < end; special++) { + ch = *special; + if ((ch == '\t') || (ch == '\n')) { + break; + } + } + } + + /* + * Special points at the next special character (or the end of the + * string). Process characters between start and special. + */ + + if (curX >= maxX) { + break; + } + start += Tk_MeasureChars(tkfont, start, special - start, maxX - curX, + 0, &width); + curX += width; + if (start < special) { + /* + * No more chars fit in line. + */ + + break; + } + if (special < end) { + if (ch == '\t') { + start++; + } else { + break; + } + } + } + + *nextXPtr = curX; + return start - source; +} |