Split the photo image core into two pieces to make it easier to maintain.

1 files changed, 262 insertions, 0 deletions

diff --git a/generic/tkImgPhoto.h b/generic/tkImgPhoto.h
new file mode 100644
index 0000000..fc1a444
--- /dev/null
+++ b/generic/tkImgPhoto.h
@@ -0,0 +1,262 @@
+/*
+ * tkImgPhoto.h --
+ *
+ *	Declarations for images of type "photo" for Tk.
+ *
+ * Copyright (c) 1994 The Australian National University.
+ * Copyright (c) 1994-1997 Sun Microsystems, Inc.
+ * Copyright (c) 2002-2008 Donal K. Fellows
+ * Copyright (c) 2003 ActiveState Corporation.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ *
+ * Author: Paul Mackerras (paulus@cs.anu.edu.au),
+ *	   Department of Computer Science,
+ *	   Australian National University.
+ *
+ * RCS: @(#) $Id: tkImgPhoto.h,v 1.1 2008/08/25 11:44:04 dkf Exp $
+ */
+
+#include "tkInt.h"
+#ifdef __WIN32__
+#include "tkWinInt.h"
+#endif
+
+/*
+ * Forward declarations of the structures we define.
+ */
+
+typedef struct ColorTableId	ColorTableId;
+typedef struct ColorTable	ColorTable;
+typedef struct PhotoInstance	PhotoInstance;
+typedef struct PhotoMaster	PhotoMaster;
+
+/*
+ * A signed 8-bit integral type. If chars are unsigned and the compiler isn't
+ * an ANSI one, then we have to use short instead (which wastes space) to get
+ * signed behavior.
+ */
+
+#if defined(__STDC__) || defined(_AIX)
+    typedef signed char schar;
+#else
+#   ifndef __CHAR_UNSIGNED__
+	typedef char schar;
+#   else
+	typedef short schar;
+#   endif
+#endif
+
+/*
+ * An unsigned 32-bit integral type, used for pixel values. We use int rather
+ * than long here to accommodate those systems where longs are 64 bits.
+ */
+
+typedef unsigned int pixel;
+
+/*
+ * The maximum number of pixels to transmit to the server in a single
+ * XPutImage call.
+ */
+
+#define MAX_PIXELS 65536
+
+/*
+ * The set of colors required to display a photo image in a window depends on:
+ *	- the visual used by the window
+ *	- the palette, which specifies how many levels of each primary color to
+ *	  use, and
+ *	- the gamma value for the image.
+ *
+ * Pixel values allocated for specific colors are valid only for the colormap
+ * in which they were allocated. Sets of pixel values allocated for displaying
+ * photos are re-used in other windows if possible, that is, if the display,
+ * colormap, palette and gamma values match. A hash table is used to locate
+ * these sets of pixel values, using the following data structure as key:
+ */
+
+struct ColorTableId {
+    Display *display;		/* Qualifies the colormap resource ID. */
+    Colormap colormap;		/* Colormap that the windows are using. */
+    double gamma;		/* Gamma exponent value for images. */
+    Tk_Uid palette;		/* Specifies how many shades of each primary
+				 * we want to allocate. */
+};
+
+/*
+ * For a particular (display, colormap, palette, gamma) combination, a data
+ * structure of the following type is used to store the allocated pixel values
+ * and other information:
+ */
+
+struct ColorTable {
+    ColorTableId id;		/* Information used in selecting this color
+				 * table. */
+    int	flags;			/* See below. */
+    int	refCount;		/* Number of instances using this map. */
+    int liveRefCount;		/* Number of instances which are actually in
+				 * use, using this map. */
+    int	numColors;		/* Number of colors allocated for this map. */
+
+    XVisualInfo	visualInfo;	/* Information about the visual for windows
+				 * using this color table. */
+
+    pixel redValues[256];	/* Maps 8-bit values of red intensity to a
+				 * pixel value or index in pixelMap. */
+    pixel greenValues[256];	/* Ditto for green intensity. */
+    pixel blueValues[256];	/* Ditto for blue intensity. */
+    unsigned long *pixelMap;	/* Actual pixel values allocated. */
+
+    unsigned char colorQuant[3][256];
+				/* Maps 8-bit intensities to quantized
+				 * intensities. The first index is 0 for red,
+				 * 1 for green, 2 for blue. */
+};
+
+/*
+ * Bit definitions for the flags field of a ColorTable.
+ * BLACK_AND_WHITE:		1 means only black and white colors are
+ *				available.
+ * COLOR_WINDOW:		1 means a full 3-D color cube has been
+ *				allocated.
+ * DISPOSE_PENDING:		1 means a call to DisposeColorTable has been
+ *				scheduled as an idle handler, but it hasn't
+ *				been invoked yet.
+ * MAP_COLORS:			1 means pixel values should be mapped through
+ *				pixelMap.
+ */
+
+#ifdef COLOR_WINDOW
+#undef COLOR_WINDOW
+#endif
+
+#define BLACK_AND_WHITE		1
+#define COLOR_WINDOW		2
+#define DISPOSE_PENDING		4
+#define MAP_COLORS		8
+
+/*
+ * Definition of the data associated with each photo image master.
+ */
+
+struct PhotoMaster {
+    Tk_ImageMaster tkMaster;	/* Tk's token for image master. NULL means the
+				 * image is being deleted. */
+    Tcl_Interp *interp;		/* Interpreter associated with the application
+				 * using this image. */
+    Tcl_Command imageCmd;	/* Token for image command (used to delete it
+				 * when the image goes away). NULL means the
+				 * image command has already been deleted. */
+    int	flags;			/* Sundry flags, defined below. */
+    int	width, height;		/* Dimensions of image. */
+    int userWidth, userHeight;	/* User-declared image dimensions. */
+    Tk_Uid palette;		/* User-specified default palette for
+				 * instances of this image. */
+    double gamma;		/* Display gamma value to correct for. */
+    char *fileString;		/* Name of file to read into image. */
+    Tcl_Obj *dataString;	/* Object to use as contents of image. */
+    Tcl_Obj *format;		/* User-specified format of data in image file
+				 * or string value. */
+    unsigned char *pix32;	/* Local storage for 32-bit image. */
+    int ditherX, ditherY;	/* Location of first incorrectly dithered
+				 * pixel in image. */
+    TkRegion validRegion;	/* Tk region indicating which parts of the
+				 * image have valid image data. */
+    PhotoInstance *instancePtr;	/* First in the list of instances associated
+				 * with this master. */
+};
+
+/*
+ * Bit definitions for the flags field of a PhotoMaster.
+ * COLOR_IMAGE:			1 means that the image has different color
+ *				components.
+ * IMAGE_CHANGED:		1 means that the instances of this image need
+ *				to be redithered.
+ * COMPLEX_ALPHA:		1 means that the instances of this image have
+ *				alpha values that aren't 0 or 255, and so need
+ *				the copy-merge-replace renderer .
+ */
+
+#define COLOR_IMAGE		1
+#define IMAGE_CHANGED		2
+#define COMPLEX_ALPHA		4
+
+/*
+ * Flag to OR with the compositing rule to indicate that the source, despite
+ * having an alpha channel, has simple alpha.
+ */
+
+#define SOURCE_IS_SIMPLE_ALPHA_PHOTO 0x10000000
+
+/*
+ * The following data structure represents all of the instances of a photo
+ * image in windows on a given screen that are using the same colormap.
+ */
+
+struct PhotoInstance {
+    PhotoMaster *masterPtr;	/* Pointer to master for image. */
+    Display *display;		/* Display for windows using this instance. */
+    Colormap colormap;		/* The image may only be used in windows with
+				 * this particular colormap. */
+    PhotoInstance *nextPtr;	/* Pointer to the next instance in the list of
+				 * instances associated with this master. */
+    int refCount;		/* Number of instances using this structure. */
+    Tk_Uid palette;		/* Palette for these particular instances. */
+    double gamma;		/* Gamma value for these instances. */
+    Tk_Uid defaultPalette;	/* Default palette to use if a palette is not
+				 * specified for the master. */
+    ColorTable *colorTablePtr;	/* Pointer to information about colors
+				 * allocated for image display in windows like
+				 * this one. */
+    Pixmap pixels;		/* X pixmap containing dithered image. */
+    int width, height;		/* Dimensions of the pixmap. */
+    schar *error;		/* Error image, used in dithering. */
+    XImage *imagePtr;		/* Image structure for converted pixels. */
+    XVisualInfo visualInfo;	/* Information about the visual that these
+				 * windows are using. */
+    GC gc;			/* Graphics context for writing images to the
+				 * pixmap. */
+};
+
+/*
+ * Implementation of the Porter-Duff Source-Over compositing rule.
+ */
+
+#define PD_SRC_OVER(srcColor,srcAlpha,dstColor,dstAlpha) \
+	(srcColor*srcAlpha/255) + dstAlpha*(255-srcAlpha)/255*dstColor/255
+#define PD_SRC_OVER_ALPHA(srcAlpha,dstAlpha) \
+	(srcAlpha + (255-srcAlpha)*dstAlpha/255)
+
+#undef MIN
+#define MIN(a, b)	((a) < (b)? (a): (b))
+#undef MAX
+#define MAX(a, b)	((a) > (b)? (a): (b))
+
+/*
+ * Declarations of functions shared between the different parts of the
+ * photo image implementation.
+ */
+
+MODULE_SCOPE void	TkImgPhotoConfigureInstance(
+			    PhotoInstance *instancePtr);
+MODULE_SCOPE void	TkImgDisposeInstance(ClientData clientData);
+MODULE_SCOPE void	TkImgPhotoInstanceSetSize(PhotoInstance *instancePtr);
+MODULE_SCOPE ClientData	TkImgPhotoGet(Tk_Window tkwin, ClientData clientData);
+MODULE_SCOPE void	TkImgDitherInstance(PhotoInstance *instancePtr, int x,
+			    int y, int width, int height);
+MODULE_SCOPE void	TkImgPhotoDisplay(ClientData clientData,
+			    Display *display, Drawable drawable,
+			    int imageX, int imageY, int width, int height,
+			    int drawableX, int drawableY);
+MODULE_SCOPE void	TkImgPhotoFree(ClientData clientData,
+			    Display *display);
+MODULE_SCOPE void	TkImgResetDither(PhotoInstance *instancePtr);
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */