Initial revision

1 files changed, 800 insertions, 0 deletions

diff --git a/generic/tkCanvBmap.c b/generic/tkCanvBmap.c
new file mode 100644
index 0000000..fff0638
--- /dev/null
+++ b/generic/tkCanvBmap.c
@@ -0,0 +1,800 @@
+/* 
+ * tkCanvBmap.c --
+ *
+ *	This file implements bitmap items for canvas widgets.
+ *
+ * Copyright (c) 1992-1994 The Regents of the University of California.
+ * Copyright (c) 1994-1995 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: @(#) tkCanvBmap.c 1.30 96/05/03 10:49:00
+ */
+
+#include <stdio.h>
+#include "tkInt.h"
+#include "tkPort.h"
+#include "tkCanvas.h"
+
+/*
+ * The structure below defines the record for each bitmap item.
+ */
+
+typedef struct BitmapItem  {
+    Tk_Item header;		/* Generic stuff that's the same for all
+				 * types.  MUST BE FIRST IN STRUCTURE. */
+    double x, y;		/* Coordinates of positioning point for
+				 * bitmap. */
+    Tk_Anchor anchor;		/* Where to anchor bitmap relative to
+				 * (x,y). */
+    Pixmap bitmap;		/* Bitmap to display in window. */
+    XColor *fgColor;		/* Foreground color to use for bitmap. */
+    XColor *bgColor;		/* Background color to use for bitmap. */
+    GC gc;			/* Graphics context to use for drawing
+				 * bitmap on screen. */
+} BitmapItem;
+
+/*
+ * Information used for parsing configuration specs:
+ */
+
+static Tk_CustomOption tagsOption = {Tk_CanvasTagsParseProc,
+    Tk_CanvasTagsPrintProc, (ClientData) NULL
+};
+
+static Tk_ConfigSpec configSpecs[] = {
+    {TK_CONFIG_ANCHOR, "-anchor", (char *) NULL, (char *) NULL,
+	"center", Tk_Offset(BitmapItem, anchor), TK_CONFIG_DONT_SET_DEFAULT},
+    {TK_CONFIG_COLOR, "-background", (char *) NULL, (char *) NULL,
+	(char *) NULL, Tk_Offset(BitmapItem, bgColor), TK_CONFIG_NULL_OK},
+    {TK_CONFIG_BITMAP, "-bitmap", (char *) NULL, (char *) NULL,
+	(char *) NULL, Tk_Offset(BitmapItem, bitmap), TK_CONFIG_NULL_OK},
+    {TK_CONFIG_COLOR, "-foreground", (char *) NULL, (char *) NULL,
+	"black", Tk_Offset(BitmapItem, fgColor), 0},
+    {TK_CONFIG_CUSTOM, "-tags", (char *) NULL, (char *) NULL,
+	(char *) NULL, 0, TK_CONFIG_NULL_OK, &tagsOption},
+    {TK_CONFIG_END, (char *) NULL, (char *) NULL, (char *) NULL,
+	(char *) NULL, 0, 0}
+};
+
+/*
+ * Prototypes for procedures defined in this file:
+ */
+
+static int		BitmapCoords _ANSI_ARGS_((Tcl_Interp *interp,
+			    Tk_Canvas canvas, Tk_Item *itemPtr, int argc,
+			    char **argv));
+static int		BitmapToArea _ANSI_ARGS_((Tk_Canvas canvas,
+			    Tk_Item *itemPtr, double *rectPtr));
+static double		BitmapToPoint _ANSI_ARGS_((Tk_Canvas canvas,
+			    Tk_Item *itemPtr, double *coordPtr));
+static int		BitmapToPostscript _ANSI_ARGS_((Tcl_Interp *interp,
+			    Tk_Canvas canvas, Tk_Item *itemPtr, int prepass));
+static void		ComputeBitmapBbox _ANSI_ARGS_((Tk_Canvas canvas,
+			    BitmapItem *bmapPtr));
+static int		ConfigureBitmap _ANSI_ARGS_((Tcl_Interp *interp,
+			    Tk_Canvas canvas, Tk_Item *itemPtr, int argc,
+			    char **argv, int flags));
+static int		CreateBitmap _ANSI_ARGS_((Tcl_Interp *interp,
+			    Tk_Canvas canvas, struct Tk_Item *itemPtr,
+			    int argc, char **argv));
+static void		DeleteBitmap _ANSI_ARGS_((Tk_Canvas canvas,
+			    Tk_Item *itemPtr, Display *display));
+static void		DisplayBitmap _ANSI_ARGS_((Tk_Canvas canvas,
+			    Tk_Item *itemPtr, Display *display, Drawable dst,
+			    int x, int y, int width, int height));
+static void		ScaleBitmap _ANSI_ARGS_((Tk_Canvas canvas,
+			    Tk_Item *itemPtr, double originX, double originY,
+			    double scaleX, double scaleY));
+static void		TranslateBitmap _ANSI_ARGS_((Tk_Canvas canvas,
+			    Tk_Item *itemPtr, double deltaX, double deltaY));
+
+/*
+ * The structures below defines the bitmap item type in terms of
+ * procedures that can be invoked by generic item code.
+ */
+
+Tk_ItemType tkBitmapType = {
+    "bitmap",				/* name */
+    sizeof(BitmapItem),			/* itemSize */
+    CreateBitmap,			/* createProc */
+    configSpecs,			/* configSpecs */
+    ConfigureBitmap,			/* configureProc */
+    BitmapCoords,			/* coordProc */
+    DeleteBitmap,			/* deleteProc */
+    DisplayBitmap,			/* displayProc */
+    0,					/* alwaysRedraw */
+    BitmapToPoint,			/* pointProc */
+    BitmapToArea,			/* areaProc */
+    BitmapToPostscript,			/* postscriptProc */
+    ScaleBitmap,			/* scaleProc */
+    TranslateBitmap,			/* translateProc */
+    (Tk_ItemIndexProc *) NULL,		/* indexProc */
+    (Tk_ItemCursorProc *) NULL,		/* icursorProc */
+    (Tk_ItemSelectionProc *) NULL,	/* selectionProc */
+    (Tk_ItemInsertProc *) NULL,		/* insertProc */
+    (Tk_ItemDCharsProc *) NULL,		/* dTextProc */
+    (Tk_ItemType *) NULL		/* nextPtr */
+};
+
+/*
+ *--------------------------------------------------------------
+ *
+ * CreateBitmap --
+ *
+ *	This procedure is invoked to create a new bitmap
+ *	item in a canvas.
+ *
+ * Results:
+ *	A standard Tcl return value.  If an error occurred in
+ *	creating the item, then an error message is left in
+ *	interp->result;  in this case itemPtr is left uninitialized,
+ *	so it can be safely freed by the caller.
+ *
+ * Side effects:
+ *	A new bitmap item is created.
+ *
+ *--------------------------------------------------------------
+ */
+
+static int
+CreateBitmap(interp, canvas, itemPtr, argc, argv)
+    Tcl_Interp *interp;			/* Interpreter for error reporting. */
+    Tk_Canvas canvas;			/* Canvas to hold new item. */
+    Tk_Item *itemPtr;			/* Record to hold new item;  header
+					 * has been initialized by caller. */
+    int argc;				/* Number of arguments in argv. */
+    char **argv;			/* Arguments describing rectangle. */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+
+    if (argc < 2) {
+	Tcl_AppendResult(interp, "wrong # args: should be \"",
+		Tk_PathName(Tk_CanvasTkwin(canvas)), " create ",
+		itemPtr->typePtr->name, " x y ?options?\"",
+		(char *) NULL);
+	return TCL_ERROR;
+    }
+
+    /*
+     * Initialize item's record.
+     */
+
+    bmapPtr->anchor = TK_ANCHOR_CENTER;
+    bmapPtr->bitmap = None;
+    bmapPtr->fgColor = NULL;
+    bmapPtr->bgColor = NULL;
+    bmapPtr->gc = None;
+
+    /*
+     * Process the arguments to fill in the item record.
+     */
+
+    if ((Tk_CanvasGetCoord(interp, canvas, argv[0], &bmapPtr->x) != TCL_OK)
+	    || (Tk_CanvasGetCoord(interp, canvas, argv[1], &bmapPtr->y)
+		!= TCL_OK)) {
+	return TCL_ERROR;
+    }
+
+    if (ConfigureBitmap(interp, canvas, itemPtr, argc-2, argv+2, 0) != TCL_OK) {
+	DeleteBitmap(canvas, itemPtr, Tk_Display(Tk_CanvasTkwin(canvas)));
+	return TCL_ERROR;
+    }
+    return TCL_OK;
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * BitmapCoords --
+ *
+ *	This procedure is invoked to process the "coords" widget
+ *	command on bitmap items.  See the user documentation for
+ *	details on what it does.
+ *
+ * Results:
+ *	Returns TCL_OK or TCL_ERROR, and sets interp->result.
+ *
+ * Side effects:
+ *	The coordinates for the given item may be changed.
+ *
+ *--------------------------------------------------------------
+ */
+
+static int
+BitmapCoords(interp, canvas, itemPtr, argc, argv)
+    Tcl_Interp *interp;			/* Used for error reporting. */
+    Tk_Canvas canvas;			/* Canvas containing item. */
+    Tk_Item *itemPtr;			/* Item whose coordinates are to be
+					 * read or modified. */
+    int argc;				/* Number of coordinates supplied in
+					 * argv. */
+    char **argv;			/* Array of coordinates: x1, y1,
+					 * x2, y2, ... */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+    char x[TCL_DOUBLE_SPACE], y[TCL_DOUBLE_SPACE];
+
+    if (argc == 0) {
+	Tcl_PrintDouble(interp, bmapPtr->x, x);
+	Tcl_PrintDouble(interp, bmapPtr->y, y);
+	Tcl_AppendResult(interp, x, " ", y, (char *) NULL);
+    } else if (argc == 2) {
+	if ((Tk_CanvasGetCoord(interp, canvas, argv[0], &bmapPtr->x) != TCL_OK)
+		|| (Tk_CanvasGetCoord(interp, canvas, argv[1], &bmapPtr->y)
+		    != TCL_OK)) {
+	    return TCL_ERROR;
+	}
+	ComputeBitmapBbox(canvas, bmapPtr);
+    } else {
+	sprintf(interp->result,
+		"wrong # coordinates: expected 0 or 2, got %d", argc);
+	return TCL_ERROR;
+    }
+    return TCL_OK;
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * ConfigureBitmap --
+ *
+ *	This procedure is invoked to configure various aspects
+ *	of a bitmap item, such as its anchor position.
+ *
+ * Results:
+ *	A standard Tcl result code.  If an error occurs, then
+ *	an error message is left in interp->result.
+ *
+ * Side effects:
+ *	Configuration information may be set for itemPtr.
+ *
+ *--------------------------------------------------------------
+ */
+
+static int
+ConfigureBitmap(interp, canvas, itemPtr, argc, argv, flags)
+    Tcl_Interp *interp;		/* Used for error reporting. */
+    Tk_Canvas canvas;		/* Canvas containing itemPtr. */
+    Tk_Item *itemPtr;		/* Bitmap item to reconfigure. */
+    int argc;			/* Number of elements in argv.  */
+    char **argv;		/* Arguments describing things to configure. */
+    int flags;			/* Flags to pass to Tk_ConfigureWidget. */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+    XGCValues gcValues;
+    GC newGC;
+    Tk_Window tkwin;
+    unsigned long mask;
+
+    tkwin = Tk_CanvasTkwin(canvas);
+    if (Tk_ConfigureWidget(interp, tkwin, configSpecs, argc, argv,
+	    (char *) bmapPtr, flags) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * A few of the options require additional processing, such as those
+     * that determine the graphics context.
+     */
+
+    gcValues.foreground = bmapPtr->fgColor->pixel;
+    mask = GCForeground;
+    if (bmapPtr->bgColor != NULL) {
+	gcValues.background = bmapPtr->bgColor->pixel;
+	mask |= GCBackground;
+    } else {
+	gcValues.clip_mask = bmapPtr->bitmap;
+	mask |= GCClipMask;
+    }
+    newGC = Tk_GetGC(tkwin, mask, &gcValues);
+    if (bmapPtr->gc != None) {
+	Tk_FreeGC(Tk_Display(tkwin), bmapPtr->gc);
+    }
+    bmapPtr->gc = newGC;
+
+    ComputeBitmapBbox(canvas, bmapPtr);
+
+    return TCL_OK;
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * DeleteBitmap --
+ *
+ *	This procedure is called to clean up the data structure
+ *	associated with a bitmap item.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Resources associated with itemPtr are released.
+ *
+ *--------------------------------------------------------------
+ */
+
+static void
+DeleteBitmap(canvas, itemPtr, display)
+    Tk_Canvas canvas;			/* Info about overall canvas widget. */
+    Tk_Item *itemPtr;			/* Item that is being deleted. */
+    Display *display;			/* Display containing window for
+					 * canvas. */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+
+    if (bmapPtr->bitmap != None) {
+	Tk_FreeBitmap(display, bmapPtr->bitmap);
+    }
+    if (bmapPtr->fgColor != NULL) {
+	Tk_FreeColor(bmapPtr->fgColor);
+    }
+    if (bmapPtr->bgColor != NULL) {
+	Tk_FreeColor(bmapPtr->bgColor);
+    }
+    if (bmapPtr->gc != NULL) {
+	Tk_FreeGC(display, bmapPtr->gc);
+    }
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * ComputeBitmapBbox --
+ *
+ *	This procedure is invoked to compute the bounding box of
+ *	all the pixels that may be drawn as part of a bitmap item.
+ *	This procedure is where the child bitmap's placement is
+ *	computed.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The fields x1, y1, x2, and y2 are updated in the header
+ *	for itemPtr.
+ *
+ *--------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static void
+ComputeBitmapBbox(canvas, bmapPtr)
+    Tk_Canvas canvas;			/* Canvas that contains item. */
+    BitmapItem *bmapPtr;		/* Item whose bbox is to be
+					 * recomputed. */
+{
+    int width, height;
+    int x, y;
+
+    x = (int) (bmapPtr->x + ((bmapPtr->x >= 0) ? 0.5 : - 0.5));
+    y = (int) (bmapPtr->y + ((bmapPtr->y >= 0) ? 0.5 : - 0.5));
+
+    if (bmapPtr->bitmap == None) {
+	bmapPtr->header.x1 = bmapPtr->header.x2 = x;
+	bmapPtr->header.y1 = bmapPtr->header.y2 = y;
+	return;
+    }
+
+    /*
+     * Compute location and size of bitmap, using anchor information.
+     */
+
+    Tk_SizeOfBitmap(Tk_Display(Tk_CanvasTkwin(canvas)), bmapPtr->bitmap,
+	    &width, &height);
+    switch (bmapPtr->anchor) {
+	case TK_ANCHOR_N:
+	    x -= width/2;
+	    break;
+	case TK_ANCHOR_NE:
+	    x -= width;
+	    break;
+	case TK_ANCHOR_E:
+	    x -= width;
+	    y -= height/2;
+	    break;
+	case TK_ANCHOR_SE:
+	    x -= width;
+	    y -= height;
+	    break;
+	case TK_ANCHOR_S:
+	    x -= width/2;
+	    y -= height;
+	    break;
+	case TK_ANCHOR_SW:
+	    y -= height;
+	    break;
+	case TK_ANCHOR_W:
+	    y -= height/2;
+	    break;
+	case TK_ANCHOR_NW:
+	    break;
+	case TK_ANCHOR_CENTER:
+	    x -= width/2;
+	    y -= height/2;
+	    break;
+    }
+
+    /*
+     * Store the information in the item header.
+     */
+
+    bmapPtr->header.x1 = x;
+    bmapPtr->header.y1 = y;
+    bmapPtr->header.x2 = x + width;
+    bmapPtr->header.y2 = y + height;
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * DisplayBitmap --
+ *
+ *	This procedure is invoked to draw a bitmap item in a given
+ *	drawable.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	ItemPtr is drawn in drawable using the transformation
+ *	information in canvas.
+ *
+ *--------------------------------------------------------------
+ */
+
+static void
+DisplayBitmap(canvas, itemPtr, display, drawable, x, y, width, height)
+    Tk_Canvas canvas;			/* Canvas that contains item. */
+    Tk_Item *itemPtr;			/* Item to be displayed. */
+    Display *display;			/* Display on which to draw item. */
+    Drawable drawable;			/* Pixmap or window in which to draw
+					 * item. */
+    int x, y, width, height;		/* Describes region of canvas that
+					 * must be redisplayed (not used). */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+    int bmapX, bmapY, bmapWidth, bmapHeight;
+    short drawableX, drawableY;
+
+    /*
+     * If the area being displayed doesn't cover the whole bitmap,
+     * then only redisplay the part of the bitmap that needs
+     * redisplay.
+     */
+
+    if (bmapPtr->bitmap != None) {
+	if (x > bmapPtr->header.x1) {
+	    bmapX = x - bmapPtr->header.x1;
+	    bmapWidth = bmapPtr->header.x2 - x;
+	} else {
+	    bmapX = 0;
+	    if ((x+width) < bmapPtr->header.x2) {
+		bmapWidth = x + width - bmapPtr->header.x1;
+	    } else {
+		bmapWidth = bmapPtr->header.x2 - bmapPtr->header.x1;
+	    }
+	}
+	if (y > bmapPtr->header.y1) {
+	    bmapY = y - bmapPtr->header.y1;
+	    bmapHeight = bmapPtr->header.y2 - y;
+	} else {
+	    bmapY = 0;
+	    if ((y+height) < bmapPtr->header.y2) {
+		bmapHeight = y + height - bmapPtr->header.y1;
+	    } else {
+		bmapHeight = bmapPtr->header.y2 - bmapPtr->header.y1;
+	    }
+	}
+	Tk_CanvasDrawableCoords(canvas,
+		(double) (bmapPtr->header.x1 + bmapX),
+		(double) (bmapPtr->header.y1 + bmapY),
+		&drawableX, &drawableY);
+
+	/*
+	 * Must modify the mask origin within the graphics context
+	 * to line up with the bitmap's origin (in order to make
+	 * bitmaps with "-background {}" work right).
+	 */
+ 
+	XSetClipOrigin(display, bmapPtr->gc, drawableX - bmapX,
+		drawableY - bmapY);
+	XCopyPlane(display, bmapPtr->bitmap, drawable,
+		bmapPtr->gc, bmapX, bmapY, (unsigned int) bmapWidth,
+		(unsigned int) bmapHeight, drawableX, drawableY, 1);
+    }
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * BitmapToPoint --
+ *
+ *	Computes the distance from a given point to a given
+ *	rectangle, in canvas units.
+ *
+ * Results:
+ *	The return value is 0 if the point whose x and y coordinates
+ *	are coordPtr[0] and coordPtr[1] is inside the bitmap.  If the
+ *	point isn't inside the bitmap then the return value is the
+ *	distance from the point to the bitmap.
+ *
+ * Side effects:
+ *	None.
+ *
+ *--------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static double
+BitmapToPoint(canvas, itemPtr, coordPtr)
+    Tk_Canvas canvas;		/* Canvas containing item. */
+    Tk_Item *itemPtr;		/* Item to check against point. */
+    double *coordPtr;		/* Pointer to x and y coordinates. */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+    double x1, x2, y1, y2, xDiff, yDiff;
+
+    x1 = bmapPtr->header.x1;
+    y1 = bmapPtr->header.y1;
+    x2 = bmapPtr->header.x2;
+    y2 = bmapPtr->header.y2;
+
+    /*
+     * Point is outside rectangle.
+     */
+
+    if (coordPtr[0] < x1) {
+	xDiff = x1 - coordPtr[0];
+    } else if (coordPtr[0] > x2)  {
+	xDiff = coordPtr[0] - x2;
+    } else {
+	xDiff = 0;
+    }
+
+    if (coordPtr[1] < y1) {
+	yDiff = y1 - coordPtr[1];
+    } else if (coordPtr[1] > y2)  {
+	yDiff = coordPtr[1] - y2;
+    } else {
+	yDiff = 0;
+    }
+
+    return hypot(xDiff, yDiff);
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * BitmapToArea --
+ *
+ *	This procedure is called to determine whether an item
+ *	lies entirely inside, entirely outside, or overlapping
+ *	a given rectangle.
+ *
+ * Results:
+ *	-1 is returned if the item is entirely outside the area
+ *	given by rectPtr, 0 if it overlaps, and 1 if it is entirely
+ *	inside the given area.
+ *
+ * Side effects:
+ *	None.
+ *
+ *--------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+BitmapToArea(canvas, itemPtr, rectPtr)
+    Tk_Canvas canvas;		/* Canvas containing item. */
+    Tk_Item *itemPtr;		/* Item to check against rectangle. */
+    double *rectPtr;		/* Pointer to array of four coordinates
+				 * (x1, y1, x2, y2) describing rectangular
+				 * area.  */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+
+    if ((rectPtr[2] <= bmapPtr->header.x1)
+	    || (rectPtr[0] >= bmapPtr->header.x2)
+	    || (rectPtr[3] <= bmapPtr->header.y1)
+	    || (rectPtr[1] >= bmapPtr->header.y2)) {
+	return -1;
+    }
+    if ((rectPtr[0] <= bmapPtr->header.x1)
+	    && (rectPtr[1] <= bmapPtr->header.y1)
+	    && (rectPtr[2] >= bmapPtr->header.x2)
+	    && (rectPtr[3] >= bmapPtr->header.y2)) {
+	return 1;
+    }
+    return 0;
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * ScaleBitmap --
+ *
+ *	This procedure is invoked to rescale a bitmap item in a
+ *	canvas.  It is one of the standard item procedures for
+ *	bitmap items, and is invoked by the generic canvas code.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The item referred to by itemPtr is rescaled so that the
+ *	following transformation is applied to all point coordinates:
+ *		x' = originX + scaleX*(x-originX)
+ *		y' = originY + scaleY*(y-originY)
+ *
+ *--------------------------------------------------------------
+ */
+
+static void
+ScaleBitmap(canvas, itemPtr, originX, originY, scaleX, scaleY)
+    Tk_Canvas canvas;			/* Canvas containing rectangle. */
+    Tk_Item *itemPtr;			/* Rectangle to be scaled. */
+    double originX, originY;		/* Origin about which to scale item. */
+    double scaleX;			/* Amount to scale in X direction. */
+    double scaleY;			/* Amount to scale in Y direction. */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+
+    bmapPtr->x = originX + scaleX*(bmapPtr->x - originX);
+    bmapPtr->y = originY + scaleY*(bmapPtr->y - originY);
+    ComputeBitmapBbox(canvas, bmapPtr);
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * TranslateBitmap --
+ *
+ *	This procedure is called to move an item by a given amount.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The position of the item is offset by (xDelta, yDelta), and
+ *	the bounding box is updated in the generic part of the item
+ *	structure.
+ *
+ *--------------------------------------------------------------
+ */
+
+static void
+TranslateBitmap(canvas, itemPtr, deltaX, deltaY)
+    Tk_Canvas canvas;			/* Canvas containing item. */
+    Tk_Item *itemPtr;			/* Item that is being moved. */
+    double deltaX, deltaY;		/* Amount by which item is to be
+					 * moved. */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+
+    bmapPtr->x += deltaX;
+    bmapPtr->y += deltaY;
+    ComputeBitmapBbox(canvas, bmapPtr);
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * BitmapToPostscript --
+ *
+ *	This procedure is called to generate Postscript for
+ *	bitmap items.
+ *
+ * Results:
+ *	The return value is a standard Tcl result.  If an error
+ *	occurs in generating Postscript then an error message is
+ *	left in interp->result, replacing whatever used to be there.
+ *	If no error occurs, then Postscript for the item is appended
+ *	to the result.
+ *
+ * Side effects:
+ *	None.
+ *
+ *--------------------------------------------------------------
+ */
+
+static int
+BitmapToPostscript(interp, canvas, itemPtr, prepass)
+    Tcl_Interp *interp;			/* Leave Postscript or error message
+					 * here. */
+    Tk_Canvas canvas;			/* Information about overall canvas. */
+    Tk_Item *itemPtr;			/* Item for which Postscript is
+					 * wanted. */
+    int prepass;			/* 1 means this is a prepass to
+					 * collect font information;  0 means
+					 * final Postscript is being created. */
+{
+    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
+    double x, y;
+    int width, height, rowsAtOnce, rowsThisTime;
+    int curRow;
+    char buffer[200];
+
+    if (bmapPtr->bitmap == None) {
+	return TCL_OK;
+    }
+
+    /*
+     * Compute the coordinates of the lower-left corner of the bitmap,
+     * taking into account the anchor position for the bitmp.
+     */
+
+    x = bmapPtr->x;
+    y = Tk_CanvasPsY(canvas, bmapPtr->y);
+    Tk_SizeOfBitmap(Tk_Display(Tk_CanvasTkwin(canvas)), bmapPtr->bitmap,
+	    &width, &height);
+    switch (bmapPtr->anchor) {
+	case TK_ANCHOR_NW:			y -= height;		break;
+	case TK_ANCHOR_N:	x -= width/2.0; y -= height;		break;
+	case TK_ANCHOR_NE:	x -= width;	y -= height;		break;
+	case TK_ANCHOR_E:	x -= width;	y -= height/2.0;	break;
+	case TK_ANCHOR_SE:	x -= width;				break;
+	case TK_ANCHOR_S:	x -= width/2.0;				break;
+	case TK_ANCHOR_SW:						break;
+	case TK_ANCHOR_W:			y -= height/2.0;	break;
+	case TK_ANCHOR_CENTER:	x -= width/2.0; y -= height/2.0;	break;
+    }
+
+    /*
+     * Color the background, if there is one.
+     */
+
+    if (bmapPtr->bgColor != NULL) {
+	sprintf(buffer,
+		"%.15g %.15g moveto %d 0 rlineto 0 %d rlineto %d %s\n",
+		x, y, width, height, -width,"0 rlineto closepath");
+	Tcl_AppendResult(interp, buffer, (char *) NULL);
+	if (Tk_CanvasPsColor(interp, canvas, bmapPtr->bgColor) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+	Tcl_AppendResult(interp, "fill\n", (char *) NULL);
+    }
+
+    /*
+     * Draw the bitmap, if there is a foreground color.  If the bitmap
+     * is very large, then chop it up into multiple bitmaps, each
+     * consisting of one or more rows.  This is needed because Postscript
+     * can't handle single strings longer than 64 KBytes long.
+     */
+
+    if (bmapPtr->fgColor != NULL) {
+	if (Tk_CanvasPsColor(interp, canvas, bmapPtr->fgColor) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+	if (width > 60000) {
+	    Tcl_ResetResult(interp);
+	    Tcl_AppendResult(interp, "can't generate Postscript",
+		    " for bitmaps more than 60000 pixels wide",
+		    (char *) NULL);
+	    return TCL_ERROR;
+	}
+	rowsAtOnce = 60000/width;
+	if (rowsAtOnce < 1) {
+	    rowsAtOnce = 1;
+	}
+	sprintf(buffer, "%.15g %.15g translate\n", x, y+height);
+	Tcl_AppendResult(interp, buffer, (char *) NULL);
+	for (curRow = 0; curRow < height; curRow += rowsAtOnce) {
+	    rowsThisTime = rowsAtOnce;
+	    if (rowsThisTime > (height - curRow)) {
+		rowsThisTime = height - curRow;
+	    }
+	    sprintf(buffer, "0 -%.15g translate\n%d %d true matrix {\n",
+		    (double) rowsThisTime, width, rowsThisTime);
+	    Tcl_AppendResult(interp, buffer, (char *) NULL);
+	    if (Tk_CanvasPsBitmap(interp, canvas, bmapPtr->bitmap,
+		    0, curRow, width, rowsThisTime) != TCL_OK) {
+		return TCL_ERROR;
+	    }
+	    Tcl_AppendResult(interp, "\n} imagemask\n", (char *) NULL);
+	}
+    }
+    return TCL_OK;
+}