stk/Tk/generic/tkImgPhoto.c

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/*
* tkImgPhoto.c --
*
* Implements images of type "photo" for Tk. Photo images are
* stored in full color (24 bits per pixel) and displayed using
* dithering if necessary.
*
* Copyright (c) 1994 The Australian National University.
* 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.
*
* Author: Paul Mackerras (paulus@cs.anu.edu.au),
* Department of Computer Science,
* Australian National University.
*
* SCCS: @(#) tkImgPhoto.c 1.60 97/08/08 11:32:46
*/
#include "tkInt.h"
#include "tkPort.h"
#ifdef SCM_CODE
# include <math.h>
#else
# include "tclMath.h"
#endif
#include <ctype.h>
/*
* Declaration for internal Xlib function used here:
*/
#ifdef SCM_CODE
extern int _XInitImageFuncPtrs _ANSI_ARGS_((XImage *image));
#else
extern _XInitImageFuncPtrs _ANSI_ARGS_((XImage *image));
#endif
/*
* 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:
*/
typedef struct {
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. */
} ColorTableId;
/*
* 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:
*/
typedef 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. */
} ColorTable;
/*
* 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.
*/
#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.
*/
typedef 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. */
char *dataString; /* String value to use as contents of image. */
char *format; /* User-specified format of data in image
* file or string value. */
unsigned char *pix24; /* Local storage for 24-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. */
struct PhotoInstance *instancePtr;
/* First in the list of instances
* associated with this master. */
} PhotoMaster;
/*
* 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.
*/
#define COLOR_IMAGE 1
#define IMAGE_CHANGED 2
/*
* 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.
*/
typedef 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. */
struct 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. */
} PhotoInstance;
/*
* The following data structure is used to return information
* from ParseSubcommandOptions:
*/
struct SubcommandOptions {
int options; /* Individual bits indicate which
* options were specified - see below. */
char *name; /* Name specified without an option. */
int fromX, fromY; /* Values specified for -from option. */
int fromX2, fromY2; /* Second coordinate pair for -from option. */
int toX, toY; /* Values specified for -to option. */
int toX2, toY2; /* Second coordinate pair for -to option. */
int zoomX, zoomY; /* Values specified for -zoom option. */
int subsampleX, subsampleY; /* Values specified for -subsample option. */
char *format; /* Value specified for -format option. */
};
/*
* Bit definitions for use with ParseSubcommandOptions:
* Each bit is set in the allowedOptions parameter on a call to
* ParseSubcommandOptions if that option is allowed for the current
* photo image subcommand. On return, the bit is set in the options
* field of the SubcommandOptions structure if that option was specified.
*
* OPT_FORMAT: Set if -format option allowed/specified.
* OPT_FROM: Set if -from option allowed/specified.
* OPT_SHRINK: Set if -shrink option allowed/specified.
* OPT_SUBSAMPLE: Set if -subsample option allowed/spec'd.
* OPT_TO: Set if -to option allowed/specified.
* OPT_ZOOM: Set if -zoom option allowed/specified.
*/
#define OPT_FORMAT 1
#define OPT_FROM 2
#define OPT_SHRINK 4
#define OPT_SUBSAMPLE 8
#define OPT_TO 0x10
#define OPT_ZOOM 0x20
/*
* List of option names. The order here must match the order of
* declarations of the OPT_* constants above.
*/
static char *optionNames[] = {
"-format",
"-from",
"-shrink",
"-subsample",
"-to",
"-zoom",
(char *) NULL
};
/*
* The type record for photo images:
*/
static int ImgPhotoCreate _ANSI_ARGS_((Tcl_Interp *interp,
char *name, int argc, char **argv,
Tk_ImageType *typePtr, Tk_ImageMaster master,
ClientData *clientDataPtr));
static ClientData ImgPhotoGet _ANSI_ARGS_((Tk_Window tkwin,
ClientData clientData));
static void ImgPhotoDisplay _ANSI_ARGS_((ClientData clientData,
Display *display, Drawable drawable,
int imageX, int imageY, int width, int height,
int drawableX, int drawableY));
static void ImgPhotoFree _ANSI_ARGS_((ClientData clientData,
Display *display));
static void ImgPhotoDelete _ANSI_ARGS_((ClientData clientData));
Tk_ImageType tkPhotoImageType = {
"photo", /* name */
ImgPhotoCreate, /* createProc */
ImgPhotoGet, /* getProc */
ImgPhotoDisplay, /* displayProc */
ImgPhotoFree, /* freeProc */
ImgPhotoDelete, /* deleteProc */
(Tk_ImageType *) NULL /* nextPtr */
};
/*
* Default configuration
*/
#define DEF_PHOTO_GAMMA "1"
#define DEF_PHOTO_HEIGHT "0"
#define DEF_PHOTO_PALETTE ""
#define DEF_PHOTO_WIDTH "0"
/*
* Information used for parsing configuration specifications:
*/
static Tk_ConfigSpec configSpecs[] = {
{TK_CONFIG_STRING, "-data", (char *) NULL, (char *) NULL,
(char *) NULL, Tk_Offset(PhotoMaster, dataString), TK_CONFIG_NULL_OK},
{TK_CONFIG_STRING, "-format", (char *) NULL, (char *) NULL,
(char *) NULL, Tk_Offset(PhotoMaster, format), TK_CONFIG_NULL_OK},
{TK_CONFIG_STRING, "-file", (char *) NULL, (char *) NULL,
(char *) NULL, Tk_Offset(PhotoMaster, fileString), TK_CONFIG_NULL_OK},
{TK_CONFIG_DOUBLE, "-gamma", (char *) NULL, (char *) NULL,
DEF_PHOTO_GAMMA, Tk_Offset(PhotoMaster, gamma), 0},
{TK_CONFIG_INT, "-height", (char *) NULL, (char *) NULL,
DEF_PHOTO_HEIGHT, Tk_Offset(PhotoMaster, userHeight), 0},
{TK_CONFIG_UID, "-palette", (char *) NULL, (char *) NULL,
DEF_PHOTO_PALETTE, Tk_Offset(PhotoMaster, palette), 0},
{TK_CONFIG_INT, "-width", (char *) NULL, (char *) NULL,
DEF_PHOTO_WIDTH, Tk_Offset(PhotoMaster, userWidth), 0},
{TK_CONFIG_END, (char *) NULL, (char *) NULL, (char *) NULL,
(char *) NULL, 0, 0}
};
/*
* Hash table used to hash from (display, colormap, palette, gamma)
* to ColorTable address.
*/
static Tcl_HashTable imgPhotoColorHash;
static int imgPhotoColorHashInitialized;
#define N_COLOR_HASH (sizeof(ColorTableId) / sizeof(int))
/*
* Pointer to the first in the list of known photo image formats.
*/
static Tk_PhotoImageFormat *formatList = NULL;
/*
* Forward declarations
*/
static int ImgPhotoCmd _ANSI_ARGS_((ClientData clientData,
Tcl_Interp *interp, int argc, char **argv));
static int ParseSubcommandOptions _ANSI_ARGS_((
struct SubcommandOptions *optPtr,
Tcl_Interp *interp, int allowedOptions,
int *indexPtr, int argc, char **argv));
static void ImgPhotoCmdDeletedProc _ANSI_ARGS_((
ClientData clientData));
static int ImgPhotoConfigureMaster _ANSI_ARGS_((
Tcl_Interp *interp, PhotoMaster *masterPtr,
int argc, char **argv, int flags));
static void ImgPhotoConfigureInstance _ANSI_ARGS_((
PhotoInstance *instancePtr));
static void ImgPhotoSetSize _ANSI_ARGS_((PhotoMaster *masterPtr,
int width, int height));
static void ImgPhotoInstanceSetSize _ANSI_ARGS_((
PhotoInstance *instancePtr));
static int IsValidPalette _ANSI_ARGS_((PhotoInstance *instancePtr,
char *palette));
static int CountBits _ANSI_ARGS_((pixel mask));
static void GetColorTable _ANSI_ARGS_((PhotoInstance *instancePtr));
static void FreeColorTable _ANSI_ARGS_((ColorTable *colorPtr));
static void AllocateColors _ANSI_ARGS_((ColorTable *colorPtr));
static void DisposeColorTable _ANSI_ARGS_((ClientData clientData));
static void DisposeInstance _ANSI_ARGS_((ClientData clientData));
static int ReclaimColors _ANSI_ARGS_((ColorTableId *id,
int numColors));
static int MatchFileFormat _ANSI_ARGS_((Tcl_Interp *interp,
Tcl_Channel chan, char *fileName,
char *formatString,
Tk_PhotoImageFormat **imageFormatPtr,
int *widthPtr, int *heightPtr));
static int MatchStringFormat _ANSI_ARGS_((Tcl_Interp *interp,
char *string, char *formatString,
Tk_PhotoImageFormat **imageFormatPtr,
int *widthPtr, int *heightPtr));
static void Dither _ANSI_ARGS_((PhotoMaster *masterPtr,
int x, int y, int width, int height));
static void DitherInstance _ANSI_ARGS_((PhotoInstance *instancePtr,
int x, int y, int width, int height));
#undef MIN
#define MIN(a, b) ((a) < (b)? (a): (b))
#undef MAX
#define MAX(a, b) ((a) > (b)? (a): (b))
/*
*----------------------------------------------------------------------
*
* Tk_CreatePhotoImageFormat --
*
* This procedure is invoked by an image file handler to register
* a new photo image format and the procedures that handle the
* new format. The procedure is typically invoked during
* Tcl_AppInit.
*
* Results:
* None.
*
* Side effects:
* The new image file format is entered into a table used in the
* photo image "read" and "write" subcommands.
*
*----------------------------------------------------------------------
*/
void
Tk_CreatePhotoImageFormat(formatPtr)
Tk_PhotoImageFormat *formatPtr;
/* Structure describing the format. All of
* the fields except "nextPtr" must be filled
* in by caller. Must not have been passed
* to Tk_CreatePhotoImageFormat previously. */
{
Tk_PhotoImageFormat *copyPtr;
copyPtr = (Tk_PhotoImageFormat *) ckalloc(sizeof(Tk_PhotoImageFormat));
*copyPtr = *formatPtr;
copyPtr->name = (char *) ckalloc((unsigned) (strlen(formatPtr->name) + 1));
strcpy(copyPtr->name, formatPtr->name);
copyPtr->nextPtr = formatList;
formatList = copyPtr;
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoCreate --
*
* This procedure is called by the Tk image code to create
* a new photo image.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* The data structure for a new photo image is allocated and
* initialized.
*
*----------------------------------------------------------------------
*/
static int
ImgPhotoCreate(interp, name, argc, argv, typePtr, master, clientDataPtr)
Tcl_Interp *interp; /* Interpreter for application containing
* image. */
char *name; /* Name to use for image. */
int argc; /* Number of arguments. */
char **argv; /* Argument strings for options (doesn't
* include image name or type). */
Tk_ImageType *typePtr; /* Pointer to our type record (not used). */
Tk_ImageMaster master; /* Token for image, to be used by us in
* later callbacks. */
ClientData *clientDataPtr; /* Store manager's token for image here;
* it will be returned in later callbacks. */
{
PhotoMaster *masterPtr;
/*
* Allocate and initialize the photo image master record.
*/
masterPtr = (PhotoMaster *) ckalloc(sizeof(PhotoMaster));
memset((void *) masterPtr, 0, sizeof(PhotoMaster));
masterPtr->tkMaster = master;
masterPtr->interp = interp;
masterPtr->imageCmd = Tcl_CreateCommand(interp, name, ImgPhotoCmd,
(ClientData) masterPtr, ImgPhotoCmdDeletedProc);
masterPtr->palette = NULL;
masterPtr->pix24 = NULL;
masterPtr->instancePtr = NULL;
masterPtr->validRegion = TkCreateRegion();
/*
* Process configuration options given in the image create command.
*/
if (ImgPhotoConfigureMaster(interp, masterPtr, argc, argv, 0) != TCL_OK) {
ImgPhotoDelete((ClientData) masterPtr);
return TCL_ERROR;
}
*clientDataPtr = (ClientData) masterPtr;
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoCmd --
*
* This procedure is invoked to process the Tcl command that
* corresponds to a photo image. See the user documentation
* for details on what it does.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* See the user documentation.
*
*----------------------------------------------------------------------
*/
static int
ImgPhotoCmd(clientData, interp, argc, argv)
ClientData clientData; /* Information about photo master. */
Tcl_Interp *interp; /* Current interpreter. */
int argc; /* Number of arguments. */
char **argv; /* Argument strings. */
{
PhotoMaster *masterPtr = (PhotoMaster *) clientData;
int c, result, index;
int x, y, width, height;
int dataWidth, dataHeight;
struct SubcommandOptions options;
int listArgc;
char **listArgv;
char **srcArgv;
unsigned char *pixelPtr;
Tk_PhotoImageBlock block;
Tk_Window tkwin;
char string[16];
XColor color;
Tk_PhotoImageFormat *imageFormat;
int imageWidth, imageHeight;
int matched;
Tcl_Channel chan;
Tk_PhotoHandle srcHandle;
size_t length;
if (argc < 2) {
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" option ?arg arg ...?\"", (char *) NULL);
return TCL_ERROR;
}
c = argv[1][0];
length = strlen(argv[1]);
if ((c == 'b') && (strncmp(argv[1], "blank", length) == 0)) {
/*
* photo blank command - just call Tk_PhotoBlank.
*/
if (argc == 2) {
Tk_PhotoBlank(masterPtr);
} else {
Tcl_AppendResult(interp, "wrong # args: should be \"",
argv[0], " blank\"", (char *) NULL);
return TCL_ERROR;
}
} else if ((c == 'c') && (length >= 2)
&& (strncmp(argv[1], "cget", length) == 0)) {
if (argc != 3) {
Tcl_AppendResult(interp, "wrong # args: should be \"",
argv[0], " cget option\"",
(char *) NULL);
return TCL_ERROR;
}
Tk_ConfigureValue(interp, Tk_MainWindow(interp), configSpecs,
(char *) masterPtr, argv[2], 0);
} else if ((c == 'c') && (length >= 3)
&& (strncmp(argv[1], "configure", length) == 0)) {
/*
* photo configure command - handle this in the standard way.
*/
if (argc == 2) {
return Tk_ConfigureInfo(interp, Tk_MainWindow(interp),
configSpecs, (char *) masterPtr, (char *) NULL, 0);
}
if (argc == 3) {
return Tk_ConfigureInfo(interp, Tk_MainWindow(interp),
configSpecs, (char *) masterPtr, argv[2], 0);
}
return ImgPhotoConfigureMaster(interp, masterPtr, argc-2, argv+2,
TK_CONFIG_ARGV_ONLY);
} else if ((c == 'c') && (length >= 3)
&& (strncmp(argv[1], "copy", length) == 0)) {
/*
* photo copy command - first parse options.
*/
index = 2;
memset((VOID *) &options, 0, sizeof(options));
options.zoomX = options.zoomY = 1;
options.subsampleX = options.subsampleY = 1;
options.name = NULL;
if (ParseSubcommandOptions(&options, interp,
OPT_FROM | OPT_TO | OPT_ZOOM | OPT_SUBSAMPLE | OPT_SHRINK,
&index, argc, argv) != TCL_OK) {
return TCL_ERROR;
}
if (options.name == NULL || index < argc) {
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" copy source-image ?-from x1 y1 x2 y2?",
" ?-to x1 y1 x2 y2? ?-zoom x y? ?-subsample x y?",
"\"", (char *) NULL);
return TCL_ERROR;
}
/*
* Look for the source image and get a pointer to its image data.
* Check the values given for the -from option.
*/
if ((srcHandle = Tk_FindPhoto(interp, options.name)) == NULL) {
Tcl_AppendResult(interp, "image \"", argv[2], "\" doesn't",
" exist or is not a photo image", (char *) NULL);
return TCL_ERROR;
}
Tk_PhotoGetImage(srcHandle, &block);
if ((options.fromX2 > block.width) || (options.fromY2 > block.height)
|| (options.fromX2 > block.width)
|| (options.fromY2 > block.height)) {
Tcl_AppendResult(interp, "coordinates for -from option extend ",
"outside source image", (char *) NULL);
return TCL_ERROR;
}
/*
* Fill in default values for unspecified parameters.
*/
if (((options.options & OPT_FROM) == 0) || (options.fromX2 < 0)) {
options.fromX2 = block.width;
options.fromY2 = block.height;
}
if (((options.options & OPT_TO) == 0) || (options.toX2 < 0)) {
width = options.fromX2 - options.fromX;
if (options.subsampleX > 0) {
width = (width + options.subsampleX - 1) / options.subsampleX;
} else if (options.subsampleX == 0) {
width = 0;
} else {
width = (width - options.subsampleX - 1) / -options.subsampleX;
}
options.toX2 = options.toX + width * options.zoomX;
height = options.fromY2 - options.fromY;
if (options.subsampleY > 0) {
height = (height + options.subsampleY - 1)
/ options.subsampleY;
} else if (options.subsampleY == 0) {
height = 0;
} else {
height = (height - options.subsampleY - 1)
/ -options.subsampleY;
}
options.toY2 = options.toY + height * options.zoomY;
}
/*
* Set the destination image size if the -shrink option was specified.
*/
if (options.options & OPT_SHRINK) {
ImgPhotoSetSize(masterPtr, options.toX2, options.toY2);
}
/*
* Copy the image data over using Tk_PhotoPutZoomedBlock.
*/
block.pixelPtr += options.fromX * block.pixelSize
+ options.fromY * block.pitch;
block.width = options.fromX2 - options.fromX;
block.height = options.fromY2 - options.fromY;
Tk_PhotoPutZoomedBlock((Tk_PhotoHandle) masterPtr, &block,
options.toX, options.toY, options.toX2 - options.toX,
options.toY2 - options.toY, options.zoomX, options.zoomY,
options.subsampleX, options.subsampleY);
} else if ((c == 'g') && (strncmp(argv[1], "get", length) == 0)) {
/*
* photo get command - first parse and check parameters.
*/
if (argc != 4) {
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" get x y\"", (char *) NULL);
return TCL_ERROR;
}
if ((Tcl_GetInt(interp, argv[2], &x) != TCL_OK)
|| (Tcl_GetInt(interp, argv[3], &y) != TCL_OK)) {
return TCL_ERROR;
}
if ((x < 0) || (x >= masterPtr->width)
|| (y < 0) || (y >= masterPtr->height)) {
Tcl_AppendResult(interp, argv[0], " get: ",
"coordinates out of range", (char *) NULL);
return TCL_ERROR;
}
/*
* Extract the value of the desired pixel and format it as a string.
*/
pixelPtr = masterPtr->pix24 + (y * masterPtr->width + x) * 3;
sprintf(string, "%d %d %d", pixelPtr[0], pixelPtr[1],
pixelPtr[2]);
Tcl_AppendResult(interp, string, (char *) NULL);
} else if ((c == 'p') && (strncmp(argv[1], "put", length) == 0)) {
/*
* photo put command - first parse the options and colors specified.
*/
index = 2;
memset((VOID *) &options, 0, sizeof(options));
options.name = NULL;
if (ParseSubcommandOptions(&options, interp, OPT_TO,
&index, argc, argv) != TCL_OK) {
return TCL_ERROR;
}
if ((options.name == NULL) || (index < argc)) {
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" put {{colors...}...} ?-to x1 y1 x2 y2?\"",
(char *) NULL);
return TCL_ERROR;
}
if (Tcl_SplitList(interp, options.name, &dataHeight, &srcArgv)
!= TCL_OK) {
return TCL_ERROR;
}
tkwin = Tk_MainWindow(interp);
block.pixelPtr = NULL;
dataWidth = 0;
pixelPtr = NULL;
for (y = 0; y < dataHeight; ++y) {
if (Tcl_SplitList(interp, srcArgv[y], &listArgc, &listArgv)
!= TCL_OK) {
break;
}
if (y == 0) {
dataWidth = listArgc;
pixelPtr = (unsigned char *) ckalloc((unsigned)
dataWidth * dataHeight * 3);
block.pixelPtr = pixelPtr;
} else {
if (listArgc != dataWidth) {
Tcl_AppendResult(interp, "all elements of color list must",
" have the same number of elements",
(char *) NULL);
ckfree((char *) listArgv);
break;
}
}
for (x = 0; x < dataWidth; ++x) {
if (!XParseColor(Tk_Display(tkwin), Tk_Colormap(tkwin),
listArgv[x], &color)) {
Tcl_AppendResult(interp, "can't parse color \"",
listArgv[x], "\"", (char *) NULL);
break;
}
*pixelPtr++ = color.red >> 8;
*pixelPtr++ = color.green >> 8;
*pixelPtr++ = color.blue >> 8;
}
ckfree((char *) listArgv);
if (x < dataWidth)
break;
}
ckfree((char *) srcArgv);
if (y < dataHeight || dataHeight == 0 || dataWidth == 0) {
if (block.pixelPtr != NULL) {
ckfree((char *) block.pixelPtr);
}
if (y < dataHeight) {
return TCL_ERROR;
}
return TCL_OK;
}
/*
* Fill in default values for the -to option, then
* copy the block in using Tk_PhotoPutBlock.
*/
if (((options.options & OPT_TO) == 0) || (options.toX2 < 0)) {
options.toX2 = options.toX + dataWidth;
options.toY2 = options.toY + dataHeight;
}
block.width = dataWidth;
block.height = dataHeight;
block.pitch = dataWidth * 3;
block.pixelSize = 3;
block.offset[0] = 0;
block.offset[1] = 1;
block.offset[2] = 2;
Tk_PhotoPutBlock((ClientData)masterPtr, &block,
options.toX, options.toY, options.toX2 - options.toX,
options.toY2 - options.toY);
ckfree((char *) block.pixelPtr);
} else if ((c == 'r') && (length >= 3)
&& (strncmp(argv[1], "read", length) == 0)) {
/*
* photo read command - first parse the options specified.
*/
index = 2;
memset((VOID *) &options, 0, sizeof(options));
options.name = NULL;
options.format = NULL;
if (ParseSubcommandOptions(&options, interp,
OPT_FORMAT | OPT_FROM | OPT_TO | OPT_SHRINK,
&index, argc, argv) != TCL_OK) {
return TCL_ERROR;
}
if ((options.name == NULL) || (index < argc)) {
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" read fileName ?-format format-name?",
" ?-from x1 y1 x2 y2? ?-to x y? ?-shrink?\"",
(char *) NULL);
return TCL_ERROR;
}
/*
* Prevent file system access in safe interpreters.
*/
if (Tcl_IsSafe(interp)) {
Tcl_AppendResult(interp, "can't get image from a file in a",
" safe interpreter", (char *) NULL);
return TCL_ERROR;
}
/*
* Open the image file and look for a handler for it.
*/
chan = Tcl_OpenFileChannel(interp, options.name, "r", 0);
if (chan == NULL) {
return TCL_ERROR;
}
if (Tcl_SetChannelOption(interp, chan, "-translation", "binary")
!= TCL_OK) {
return TCL_ERROR;
}
if (MatchFileFormat(interp, chan, options.name, options.format,
&imageFormat, &imageWidth, &imageHeight) != TCL_OK) {
Tcl_Close(NULL, chan);
return TCL_ERROR;
}
/*
* Check the values given for the -from option.
*/
if ((options.fromX > imageWidth) || (options.fromY > imageHeight)
|| (options.fromX2 > imageWidth)
|| (options.fromY2 > imageHeight)) {
Tcl_AppendResult(interp, "coordinates for -from option extend ",
"outside source image", (char *) NULL);
Tcl_Close(NULL, chan);
return TCL_ERROR;
}
if (((options.options & OPT_FROM) == 0) || (options.fromX2 < 0)) {
width = imageWidth - options.fromX;
height = imageHeight - options.fromY;
} else {
width = options.fromX2 - options.fromX;
height = options.fromY2 - options.fromY;
}
/*
* If the -shrink option was specified, set the size of the image.
*/
if (options.options & OPT_SHRINK) {
ImgPhotoSetSize(masterPtr, options.toX + width,
options.toY + height);
}
/*
* Call the handler's file read procedure to read the data
* into the image.
*/
result = (*imageFormat->fileReadProc)(interp, chan, options.name,
options.format, (Tk_PhotoHandle) masterPtr, options.toX,
options.toY, width, height, options.fromX, options.fromY);
if (chan != NULL) {
Tcl_Close(NULL, chan);
}
return result;
} else if ((c == 'r') && (length >= 3)
&& (strncmp(argv[1], "redither", length) == 0)) {
if (argc == 2) {
/*
* Call Dither if any part of the image is not correctly
* dithered at present.
*/
x = masterPtr->ditherX;
y = masterPtr->ditherY;
if (masterPtr->ditherX != 0) {
Dither(masterPtr, x, y, masterPtr->width - x, 1);
}
if (masterPtr->ditherY < masterPtr->height) {
x = 0;
Dither(masterPtr, 0, masterPtr->ditherY, masterPtr->width,
masterPtr->height - masterPtr->ditherY);
}
if (y < masterPtr->height) {
/*
* Tell the core image code that part of the image has changed.
*/
Tk_ImageChanged(masterPtr->tkMaster, x, y,
(masterPtr->width - x), (masterPtr->height - y),
masterPtr->width, masterPtr->height);
}
} else {
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" redither\"", (char *) NULL);
return TCL_ERROR;
}
} else if ((c == 'w') && (strncmp(argv[1], "write", length) == 0)) {
/*
* Prevent file system access in safe interpreters.
*/
if (Tcl_IsSafe(interp)) {
Tcl_AppendResult(interp, "can't write image to a file in a",
" safe interpreter", (char *) NULL);
return TCL_ERROR;
}
/*
* photo write command - first parse and check any options given.
*/
index = 2;
memset((VOID *) &options, 0, sizeof(options));
options.name = NULL;
options.format = NULL;
if (ParseSubcommandOptions(&options, interp, OPT_FORMAT | OPT_FROM,
&index, argc, argv) != TCL_OK) {
return TCL_ERROR;
}
if ((options.name == NULL) || (index < argc)) {
Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
" write fileName ?-format format-name?",
"?-from x1 y1 x2 y2?\"", (char *) NULL);
return TCL_ERROR;
}
if ((options.fromX > masterPtr->width)
|| (options.fromY > masterPtr->height)
|| (options.fromX2 > masterPtr->width)
|| (options.fromY2 > masterPtr->height)) {
Tcl_AppendResult(interp, "coordinates for -from option extend ",
"outside image", (char *) NULL);
return TCL_ERROR;
}
/*
* Fill in default values for unspecified parameters.
*/
if (((options.options & OPT_FROM) == 0) || (options.fromX2 < 0)) {
options.fromX2 = masterPtr->width;
options.fromY2 = masterPtr->height;
}
/*
* Search for an appropriate image file format handler,
* and give an error if none is found.
*/
matched = 0;
for (imageFormat = formatList; imageFormat != NULL;
imageFormat = imageFormat->nextPtr) {
if ((options.format == NULL)
|| (strncasecmp(options.format, imageFormat->name,
strlen(imageFormat->name)) == 0)) {
matched = 1;
if (imageFormat->fileWriteProc != NULL) {
break;
}
}
}
if (imageFormat == NULL) {
if (options.format == NULL) {
Tcl_AppendResult(interp, "no available image file format ",
"has file writing capability", (char *) NULL);
} else if (!matched) {
Tcl_AppendResult(interp, "image file format \"",
options.format, "\" is unknown", (char *) NULL);
} else {
Tcl_AppendResult(interp, "image file format \"",
options.format, "\" has no file writing capability",
(char *) NULL);
}
return TCL_ERROR;
}
/*
* Call the handler's file write procedure to write out
* the image.
*/
Tk_PhotoGetImage((Tk_PhotoHandle) masterPtr, &block);
block.pixelPtr += options.fromY * block.pitch + options.fromX * 3;
block.width = options.fromX2 - options.fromX;
block.height = options.fromY2 - options.fromY;
return (*imageFormat->fileWriteProc)(interp, options.name,
options.format, &block);
} else {
Tcl_AppendResult(interp, "bad option \"", argv[1],
"\": must be blank, cget, configure, copy, get, put,",
" read, redither, or write", (char *) NULL);
return TCL_ERROR;
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* ParseSubcommandOptions --
*
* This procedure is invoked to process one of the options
* which may be specified for the photo image subcommands,
* namely, -from, -to, -zoom, -subsample, -format, and -shrink.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* Fields in *optPtr get filled in.
*
*----------------------------------------------------------------------
*/
static int
ParseSubcommandOptions(optPtr, interp, allowedOptions, optIndexPtr, argc, argv)
struct SubcommandOptions *optPtr;
/* Information about the options specified
* and the values given is returned here. */
Tcl_Interp *interp; /* Interpreter to use for reporting errors. */
int allowedOptions; /* Indicates which options are valid for
* the current command. */
int *optIndexPtr; /* Points to a variable containing the
* current index in argv; this variable is
* updated by this procedure. */
int argc; /* Number of arguments in argv[]. */
char **argv; /* Arguments to be parsed. */
{
int index, c, bit, currentBit;
size_t length;
char *option, **listPtr;
int values[4];
int numValues, maxValues, argIndex;
for (index = *optIndexPtr; index < argc; *optIndexPtr = ++index) {
/*
* We can have one value specified without an option;
* it goes into optPtr->name.
*/
option = argv[index];
if (option[0] != '-') {
if (optPtr->name == NULL) {
optPtr->name = option;
continue;
}
break;
}
/*
* Work out which option this is.
*/
length = strlen(option);
c = option[0];
bit = 0;
currentBit = 1;
for (listPtr = optionNames; *listPtr != NULL; ++listPtr) {
if ((c == *listPtr[0])
&& (strncmp(option, *listPtr, length) == 0)) {
if (bit != 0) {
bit = 0; /* An ambiguous option. */
break;
}
bit = currentBit;
}
currentBit <<= 1;
}
/*
* If this option is not recognized and allowed, put
* an error message in the interpreter and return.
*/
if ((allowedOptions & bit) == 0) {
Tcl_AppendResult(interp, "unrecognized option \"", argv[index],
"\": must be ", (char *)NULL);
bit = 1;
for (listPtr = optionNames; *listPtr != NULL; ++listPtr) {
if ((allowedOptions & bit) != 0) {
if ((allowedOptions & (bit - 1)) != 0) {
Tcl_AppendResult(interp, ", ", (char *) NULL);
if ((allowedOptions & ~((bit << 1) - 1)) == 0) {
Tcl_AppendResult(interp, "or ", (char *) NULL);
}
}
Tcl_AppendResult(interp, *listPtr, (char *) NULL);
}
bit <<= 1;
}
return TCL_ERROR;
}
/*
* For the -from, -to, -zoom and -subsample options,
* parse the values given. Report an error if too few
* or too many values are given.
*/
if ((bit != OPT_SHRINK) && (bit != OPT_FORMAT)) {
maxValues = ((bit == OPT_FROM) || (bit == OPT_TO))? 4: 2;
argIndex = index + 1;
for (numValues = 0; numValues < maxValues; ++numValues) {
if ((argIndex < argc) && (isdigit(UCHAR(argv[argIndex][0]))
|| ((argv[argIndex][0] == '-')
&& (isdigit(UCHAR(argv[argIndex][1])))))) {
if (Tcl_GetInt(interp, argv[argIndex], &values[numValues])
!= TCL_OK) {
return TCL_ERROR;
}
} else {
break;
}
++argIndex;
}
if (numValues == 0) {
Tcl_AppendResult(interp, "the \"", argv[index], "\" option ",
"requires one ", maxValues == 2? "or two": "to four",
" integer values", (char *) NULL);
return TCL_ERROR;
}
*optIndexPtr = (index += numValues);
/*
* Y values default to the corresponding X value if not specified.
*/
if (numValues == 1) {
values[1] = values[0];
}
if (numValues == 3) {
values[3] = values[2];
}
/*
* Check the values given and put them in the appropriate
* field of the SubcommandOptions structure.
*/
switch (bit) {
case OPT_FROM:
if ((values[0] < 0) || (values[1] < 0) || ((numValues > 2)
&& ((values[2] < 0) || (values[3] < 0)))) {
Tcl_AppendResult(interp, "value(s) for the -from",
" option must be non-negative", (char *) NULL);
return TCL_ERROR;
}
if (numValues <= 2) {
optPtr->fromX = values[0];
optPtr->fromY = values[1];
optPtr->fromX2 = -1;
optPtr->fromY2 = -1;
} else {
optPtr->fromX = MIN(values[0], values[2]);
optPtr->fromY = MIN(values[1], values[3]);
optPtr->fromX2 = MAX(values[0], values[2]);
optPtr->fromY2 = MAX(values[1], values[3]);
}
break;
case OPT_SUBSAMPLE:
optPtr->subsampleX = values[0];
optPtr->subsampleY = values[1];
break;
case OPT_TO:
if ((values[0] < 0) || (values[1] < 0) || ((numValues > 2)
&& ((values[2] < 0) || (values[3] < 0)))) {
Tcl_AppendResult(interp, "value(s) for the -to",
" option must be non-negative", (char *) NULL);
return TCL_ERROR;
}
if (numValues <= 2) {
optPtr->toX = values[0];
optPtr->toY = values[1];
optPtr->toX2 = -1;
optPtr->toY2 = -1;
} else {
optPtr->toX = MIN(values[0], values[2]);
optPtr->toY = MIN(values[1], values[3]);
optPtr->toX2 = MAX(values[0], values[2]);
optPtr->toY2 = MAX(values[1], values[3]);
}
break;
case OPT_ZOOM:
if ((values[0] <= 0) || (values[1] <= 0)) {
Tcl_AppendResult(interp, "value(s) for the -zoom",
" option must be positive", (char *) NULL);
return TCL_ERROR;
}
optPtr->zoomX = values[0];
optPtr->zoomY = values[1];
break;
}
} else if (bit == OPT_FORMAT) {
/*
* The -format option takes a single string value.
*/
if (index + 1 < argc) {
*optIndexPtr = ++index;
optPtr->format = argv[index];
} else {
Tcl_AppendResult(interp, "the \"-format\" option ",
"requires a value", (char *) NULL);
return TCL_ERROR;
}
}
/*
* Remember that we saw this option.
*/
optPtr->options |= bit;
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoConfigureMaster --
*
* This procedure is called when a photo image is created or
* reconfigured. It processes configuration options and resets
* any instances of the image.
*
* Results:
* A standard Tcl return value. If TCL_ERROR is returned then
* an error message is left in masterPtr->interp->result.
*
* Side effects:
* Existing instances of the image will be redisplayed to match
* the new configuration options.
*
*----------------------------------------------------------------------
*/
static int
ImgPhotoConfigureMaster(interp, masterPtr, argc, argv, flags)
Tcl_Interp *interp; /* Interpreter to use for reporting errors. */
PhotoMaster *masterPtr; /* Pointer to data structure describing
* overall photo image to (re)configure. */
int argc; /* Number of entries in argv. */
char **argv; /* Pairs of configuration options for image. */
int flags; /* Flags to pass to Tk_ConfigureWidget,
* such as TK_CONFIG_ARGV_ONLY. */
{
PhotoInstance *instancePtr;
char *oldFileString, *oldDataString, *oldPaletteString;
double oldGamma;
int result;
Tcl_Channel chan;
Tk_PhotoImageFormat *imageFormat;
int imageWidth, imageHeight;
/*
* Save the current values for fileString and dataString, so we
* can tell if the user specifies them anew.
*/
oldFileString = masterPtr->fileString;
oldDataString = (oldFileString == NULL)? masterPtr->dataString: NULL;
oldPaletteString = masterPtr->palette;
oldGamma = masterPtr->gamma;
/*
* Process the configuration options specified.
*/
if (Tk_ConfigureWidget(interp, Tk_MainWindow(interp), configSpecs,
argc, argv, (char *) masterPtr, flags) != TCL_OK) {
return TCL_ERROR;
}
/*
* Regard the empty string for -file, -data or -format as the null
* value.
*/
if ((masterPtr->fileString != NULL) && (masterPtr->fileString[0] == 0)) {
ckfree(masterPtr->fileString);
masterPtr->fileString = NULL;
}
if ((masterPtr->dataString != NULL) && (masterPtr->dataString[0] == 0)) {
ckfree(masterPtr->dataString);
masterPtr->dataString = NULL;
}
if ((masterPtr->format != NULL) && (masterPtr->format[0] == 0)) {
ckfree(masterPtr->format);
masterPtr->format = NULL;
}
/*
* Set the image to the user-requested size, if any,
* and make sure storage is correctly allocated for this image.
*/
ImgPhotoSetSize(masterPtr, masterPtr->width, masterPtr->height);
/*
* Read in the image from the file or string if the user has
* specified the -file or -data option.
*/
if ((masterPtr->fileString != NULL)
&& (masterPtr->fileString != oldFileString)) {
/*
* Prevent file system access in a safe interpreter.
*/
if (Tcl_IsSafe(interp)) {
Tcl_AppendResult(interp, "can't get image from a file in a",
" safe interpreter", (char *) NULL);
return TCL_ERROR;
}
#if defined(SCM_CODE) && defined(WIN32)
chan = Tcl_OpenFileChannel(interp, masterPtr->fileString, "rb", 0);
#else
chan = Tcl_OpenFileChannel(interp, masterPtr->fileString, "r", 0);
#endif
if (chan == NULL) {
return TCL_ERROR;
}
#ifndef SCM_CODE
if (Tcl_SetChannelOption(interp, chan, "-translation", "binary")
!= TCL_OK) {
return TCL_ERROR;
}
#endif
if (MatchFileFormat(interp, chan, masterPtr->fileString,
masterPtr->format, &imageFormat, &imageWidth,
&imageHeight) != TCL_OK) {
Tcl_Close(NULL, chan);
return TCL_ERROR;
}
ImgPhotoSetSize(masterPtr, imageWidth, imageHeight);
result = (*imageFormat->fileReadProc)(interp, chan,
masterPtr->fileString, masterPtr->format,
(Tk_PhotoHandle) masterPtr, 0, 0,
imageWidth, imageHeight, 0, 0);
Tcl_Close(NULL, chan);
if (result != TCL_OK) {
return TCL_ERROR;
}
masterPtr->flags |= IMAGE_CHANGED;
}
if ((masterPtr->fileString == NULL) && (masterPtr->dataString != NULL)
&& (masterPtr->dataString != oldDataString)) {
if (MatchStringFormat(interp, masterPtr->dataString,
masterPtr->format, &imageFormat, &imageWidth,
&imageHeight) != TCL_OK) {
return TCL_ERROR;
}
ImgPhotoSetSize(masterPtr, imageWidth, imageHeight);
if ((*imageFormat->stringReadProc)(interp, masterPtr->dataString,
masterPtr->format, (Tk_PhotoHandle) masterPtr,
0, 0, imageWidth, imageHeight, 0, 0) != TCL_OK) {
return TCL_ERROR;
}
masterPtr->flags |= IMAGE_CHANGED;
}
/*
* Enforce a reasonable value for gamma.
*/
if (masterPtr->gamma <= 0) {
masterPtr->gamma = 1.0;
}
if ((masterPtr->gamma != oldGamma)
|| (masterPtr->palette != oldPaletteString)) {
masterPtr->flags |= IMAGE_CHANGED;
}
/*
* Cycle through all of the instances of this image, regenerating
* the information for each instance. Then force the image to be
* redisplayed everywhere that it is used.
*/
for (instancePtr = masterPtr->instancePtr; instancePtr != NULL;
instancePtr = instancePtr->nextPtr) {
ImgPhotoConfigureInstance(instancePtr);
}
/*
* Inform the generic image code that the image
* has (potentially) changed.
*/
Tk_ImageChanged(masterPtr->tkMaster, 0, 0, masterPtr->width,
masterPtr->height, masterPtr->width, masterPtr->height);
masterPtr->flags &= ~IMAGE_CHANGED;
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoConfigureInstance --
*
* This procedure is called to create displaying information for
* a photo image instance based on the configuration information
* in the master. It is invoked both when new instances are
* created and when the master is reconfigured.
*
* Results:
* None.
*
* Side effects:
* Generates errors via Tcl_BackgroundError if there are problems
* in setting up the instance.
*
*----------------------------------------------------------------------
*/
static void
ImgPhotoConfigureInstance(instancePtr)
PhotoInstance *instancePtr; /* Instance to reconfigure. */
{
PhotoMaster *masterPtr = instancePtr->masterPtr;
XImage *imagePtr;
int bitsPerPixel;
ColorTable *colorTablePtr;
XRectangle validBox;
/*
* If the -palette configuration option has been set for the master,
* use the value specified for our palette, but only if it is
* a valid palette for our windows. Use the gamma value specified
* the master.
*/
if ((masterPtr->palette && masterPtr->palette[0])
&& IsValidPalette(instancePtr, masterPtr->palette)) {
instancePtr->palette = masterPtr->palette;
} else {
instancePtr->palette = instancePtr->defaultPalette;
}
instancePtr->gamma = masterPtr->gamma;
/*
* If we don't currently have a color table, or if the one we
* have no longer applies (e.g. because our palette or gamma
* has changed), get a new one.
*/
colorTablePtr = instancePtr->colorTablePtr;
if ((colorTablePtr == NULL)
|| (instancePtr->colormap != colorTablePtr->id.colormap)
|| (instancePtr->palette != colorTablePtr->id.palette)
|| (instancePtr->gamma != colorTablePtr->id.gamma)) {
/*
* Free up our old color table, and get a new one.
*/
if (colorTablePtr != NULL) {
colorTablePtr->liveRefCount -= 1;
FreeColorTable(colorTablePtr);
}
GetColorTable(instancePtr);
/*
* Create a new XImage structure for sending data to
* the X server, if necessary.
*/
if (instancePtr->colorTablePtr->flags & BLACK_AND_WHITE) {
bitsPerPixel = 1;
} else {
bitsPerPixel = instancePtr->visualInfo.depth;
}
if ((instancePtr->imagePtr == NULL)
|| (instancePtr->imagePtr->bits_per_pixel != bitsPerPixel)) {
if (instancePtr->imagePtr != NULL) {
XFree((char *) instancePtr->imagePtr);
}
imagePtr = XCreateImage(instancePtr->display,
instancePtr->visualInfo.visual, (unsigned) bitsPerPixel,
(bitsPerPixel > 1? ZPixmap: XYBitmap), 0, (char *) NULL,
1, 1, 32, 0);
instancePtr->imagePtr = imagePtr;
/*
* Determine the endianness of this machine.
* We create images using the local host's endianness, rather
* than the endianness of the server; otherwise we would have
* to byte-swap any 16 or 32 bit values that we store in the
* image in those situations where the server's endianness
* is different from ours.
*/
if (imagePtr != NULL) {
union {
int i;
char c[sizeof(int)];
} kludge;
imagePtr->bitmap_unit = sizeof(pixel) * NBBY;
kludge.i = 0;
kludge.c[0] = 1;
imagePtr->byte_order = (kludge.i == 1) ? LSBFirst : MSBFirst;
_XInitImageFuncPtrs(imagePtr);
}
}
}
/*
* If the user has specified a width and/or height for the master
* which is different from our current width/height, set the size
* to the values specified by the user. If we have no pixmap, we
* do this also, since it has the side effect of allocating a
* pixmap for us.
*/
if ((instancePtr->pixels == None) || (instancePtr->error == NULL)
|| (instancePtr->width != masterPtr->width)
|| (instancePtr->height != masterPtr->height)) {
ImgPhotoInstanceSetSize(instancePtr);
}
/*
* Redither this instance if necessary.
*/
if ((masterPtr->flags & IMAGE_CHANGED)
|| (instancePtr->colorTablePtr != colorTablePtr)) {
TkClipBox(masterPtr->validRegion, &validBox);
if ((validBox.width > 0) && (validBox.height > 0)) {
DitherInstance(instancePtr, validBox.x, validBox.y,
validBox.width, validBox.height);
}
}
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoGet --
*
* This procedure is called for each use of a photo image in a
* widget.
*
* Results:
* The return value is a token for the instance, which is passed
* back to us in calls to ImgPhotoDisplay and ImgPhotoFree.
*
* Side effects:
* A data structure is set up for the instance (or, an existing
* instance is re-used for the new one).
*
*----------------------------------------------------------------------
*/
static ClientData
ImgPhotoGet(tkwin, masterData)
Tk_Window tkwin; /* Window in which the instance will be
* used. */
ClientData masterData; /* Pointer to our master structure for the
* image. */
{
PhotoMaster *masterPtr = (PhotoMaster *) masterData;
PhotoInstance *instancePtr;
Colormap colormap;
int mono, nRed, nGreen, nBlue;
XVisualInfo visualInfo, *visInfoPtr;
XRectangle validBox;
char buf[16];
int numVisuals;
XColor *white, *black;
XGCValues gcValues;
/*
* Table of "best" choices for palette for PseudoColor displays
* with between 3 and 15 bits/pixel.
*/
static int paletteChoice[13][3] = {
/* #red, #green, #blue */
{2, 2, 2, /* 3 bits, 8 colors */},
{2, 3, 2, /* 4 bits, 12 colors */},
{3, 4, 2, /* 5 bits, 24 colors */},
{4, 5, 3, /* 6 bits, 60 colors */},
{5, 6, 4, /* 7 bits, 120 colors */},
{7, 7, 4, /* 8 bits, 198 colors */},
{8, 10, 6, /* 9 bits, 480 colors */},
{10, 12, 8, /* 10 bits, 960 colors */},
{14, 15, 9, /* 11 bits, 1890 colors */},
{16, 20, 12, /* 12 bits, 3840 colors */},
{20, 24, 16, /* 13 bits, 7680 colors */},
{26, 30, 20, /* 14 bits, 15600 colors */},
{32, 32, 30, /* 15 bits, 30720 colors */}
};
/*
* See if there is already an instance for windows using
* the same colormap. If so then just re-use it.
*/
colormap = Tk_Colormap(tkwin);
for (instancePtr = masterPtr->instancePtr; instancePtr != NULL;
instancePtr = instancePtr->nextPtr) {
if ((colormap == instancePtr->colormap)
&& (Tk_Display(tkwin) == instancePtr->display)) {
/*
* Re-use this instance.
*/
if (instancePtr->refCount == 0) {
/*
* We are resurrecting this instance.
*/
Tcl_CancelIdleCall(DisposeInstance, (ClientData) instancePtr);
if (instancePtr->colorTablePtr != NULL) {
FreeColorTable(instancePtr->colorTablePtr);
}
GetColorTable(instancePtr);
}
instancePtr->refCount++;
return (ClientData) instancePtr;
}
}
/*
* The image isn't already in use in a window with the same colormap.
* Make a new instance of the image.
*/
instancePtr = (PhotoInstance *) ckalloc(sizeof(PhotoInstance));
instancePtr->masterPtr = masterPtr;
instancePtr->display = Tk_Display(tkwin);
instancePtr->colormap = Tk_Colormap(tkwin);
Tk_PreserveColormap(instancePtr->display, instancePtr->colormap);
instancePtr->refCount = 1;
instancePtr->colorTablePtr = NULL;
instancePtr->pixels = None;
instancePtr->error = NULL;
instancePtr->width = 0;
instancePtr->height = 0;
instancePtr->imagePtr = 0;
instancePtr->nextPtr = masterPtr->instancePtr;
masterPtr->instancePtr = instancePtr;
/*
* Obtain information about the visual and decide on the
* default palette.
*/
visualInfo.screen = Tk_ScreenNumber(tkwin);
visualInfo.visualid = XVisualIDFromVisual(Tk_Visual(tkwin));
visInfoPtr = XGetVisualInfo(Tk_Display(tkwin),
VisualScreenMask | VisualIDMask, &visualInfo, &numVisuals);
nRed = 2;
nGreen = nBlue = 0;
mono = 1;
if (visInfoPtr != NULL) {
instancePtr->visualInfo = *visInfoPtr;
switch (visInfoPtr->class) {
case DirectColor:
case TrueColor:
nRed = 1 << CountBits(visInfoPtr->red_mask);
nGreen = 1 << CountBits(visInfoPtr->green_mask);
nBlue = 1 << CountBits(visInfoPtr->blue_mask);
mono = 0;
break;
case PseudoColor:
case StaticColor:
if (visInfoPtr->depth > 15) {
nRed = 32;
nGreen = 32;
nBlue = 32;
mono = 0;
} else if (visInfoPtr->depth >= 3) {
int *ip = paletteChoice[visInfoPtr->depth - 3];
nRed = ip[0];
nGreen = ip[1];
nBlue = ip[2];
mono = 0;
}
break;
case GrayScale:
case StaticGray:
nRed = 1 << visInfoPtr->depth;
break;
}
XFree((char *) visInfoPtr);
} else {
panic("ImgPhotoGet couldn't find visual for window");
}
sprintf(buf, ((mono) ? "%d": "%d/%d/%d"), nRed, nGreen, nBlue);
instancePtr->defaultPalette = Tk_GetUid(buf);
/*
* Make a GC with background = black and foreground = white.
*/
white = Tk_GetColor(masterPtr->interp, tkwin, "white");
black = Tk_GetColor(masterPtr->interp, tkwin, "black");
gcValues.foreground = (white != NULL)? white->pixel:
WhitePixelOfScreen(Tk_Screen(tkwin));
gcValues.background = (black != NULL)? black->pixel:
BlackPixelOfScreen(Tk_Screen(tkwin));
gcValues.graphics_exposures = False;
instancePtr->gc = Tk_GetGC(tkwin,
GCForeground|GCBackground|GCGraphicsExposures, &gcValues);
/*
* Set configuration options and finish the initialization of the instance.
*/
ImgPhotoConfigureInstance(instancePtr);
/*
* If this is the first instance, must set the size of the image.
*/
if (instancePtr->nextPtr == NULL) {
Tk_ImageChanged(masterPtr->tkMaster, 0, 0, 0, 0,
masterPtr->width, masterPtr->height);
}
/*
* Dither the image to fill in this instance's pixmap.
*/
TkClipBox(masterPtr->validRegion, &validBox);
if ((validBox.width > 0) && (validBox.height > 0)) {
DitherInstance(instancePtr, validBox.x, validBox.y, validBox.width,
validBox.height);
}
return (ClientData) instancePtr;
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoDisplay --
*
* This procedure is invoked to draw a photo image.
*
* Results:
* None.
*
* Side effects:
* A portion of the image gets rendered in a pixmap or window.
*
*----------------------------------------------------------------------
*/
static void
ImgPhotoDisplay(clientData, display, drawable, imageX, imageY, width,
height, drawableX, drawableY)
ClientData clientData; /* Pointer to PhotoInstance structure for
* for instance to be displayed. */
Display *display; /* Display on which to draw image. */
Drawable drawable; /* Pixmap or window in which to draw image. */
int imageX, imageY; /* Upper-left corner of region within image
* to draw. */
int width, height; /* Dimensions of region within image to draw. */
int drawableX, drawableY; /* Coordinates within drawable that
* correspond to imageX and imageY. */
{
PhotoInstance *instancePtr = (PhotoInstance *) clientData;
/*
* If there's no pixmap, it means that an error occurred
* while creating the image instance so it can't be displayed.
*/
if (instancePtr->pixels == None) {
return;
}
/*
* masterPtr->region describes which parts of the image contain
* valid data. We set this region as the clip mask for the gc,
* setting its origin appropriately, and use it when drawing the
* image.
*/
TkSetRegion(display, instancePtr->gc, instancePtr->masterPtr->validRegion);
XSetClipOrigin(display, instancePtr->gc, drawableX - imageX,
drawableY - imageY);
XCopyArea(display, instancePtr->pixels, drawable, instancePtr->gc,
imageX, imageY, (unsigned) width, (unsigned) height,
drawableX, drawableY);
XSetClipMask(display, instancePtr->gc, None);
XSetClipOrigin(display, instancePtr->gc, 0, 0);
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoFree --
*
* This procedure is called when a widget ceases to use a
* particular instance of an image. We don't actually get
* rid of the instance until later because we may be about
* to get this instance again.
*
* Results:
* None.
*
* Side effects:
* Internal data structures get cleaned up, later.
*
*----------------------------------------------------------------------
*/
static void
ImgPhotoFree(clientData, display)
ClientData clientData; /* Pointer to PhotoInstance structure for
* for instance to be displayed. */
Display *display; /* Display containing window that used image. */
{
PhotoInstance *instancePtr = (PhotoInstance *) clientData;
ColorTable *colorPtr;
instancePtr->refCount -= 1;
if (instancePtr->refCount > 0) {
return;
}
/*
* There are no more uses of the image within this widget.
* Decrement the count of live uses of its color table, so
* that its colors can be reclaimed if necessary, and
* set up an idle call to free the instance structure.
*/
colorPtr = instancePtr->colorTablePtr;
if (colorPtr != NULL) {
colorPtr->liveRefCount -= 1;
}
Tcl_DoWhenIdle(DisposeInstance, (ClientData) instancePtr);
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoDelete --
*
* This procedure is called by the image code to delete the
* master structure for an image.
*
* Results:
* None.
*
* Side effects:
* Resources associated with the image get freed.
*
*----------------------------------------------------------------------
*/
static void
ImgPhotoDelete(masterData)
ClientData masterData; /* Pointer to PhotoMaster structure for
* image. Must not have any more instances. */
{
PhotoMaster *masterPtr = (PhotoMaster *) masterData;
PhotoInstance *instancePtr;
while ((instancePtr = masterPtr->instancePtr) != NULL) {
if (instancePtr->refCount > 0) {
panic("tried to delete photo image when instances still exist");
}
Tcl_CancelIdleCall(DisposeInstance, (ClientData) instancePtr);
DisposeInstance((ClientData) instancePtr);
}
masterPtr->tkMaster = NULL;
if (masterPtr->imageCmd != NULL) {
Tcl_DeleteCommandFromToken(masterPtr->interp, masterPtr->imageCmd);
}
if (masterPtr->pix24 != NULL) {
ckfree((char *) masterPtr->pix24);
}
if (masterPtr->validRegion != NULL) {
TkDestroyRegion(masterPtr->validRegion);
}
Tk_FreeOptions(configSpecs, (char *) masterPtr, (Display *) NULL, 0);
ckfree((char *) masterPtr);
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoCmdDeletedProc --
*
* This procedure is invoked when the image command for an image
* is deleted. It deletes the image.
*
* Results:
* None.
*
* Side effects:
* The image is deleted.
*
*----------------------------------------------------------------------
*/
static void
ImgPhotoCmdDeletedProc(clientData)
ClientData clientData; /* Pointer to PhotoMaster structure for
* image. */
{
PhotoMaster *masterPtr = (PhotoMaster *) clientData;
masterPtr->imageCmd = NULL;
if (masterPtr->tkMaster != NULL) {
Tk_DeleteImage(masterPtr->interp, Tk_NameOfImage(masterPtr->tkMaster));
}
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoSetSize --
*
* This procedure reallocates the image storage and instance
* pixmaps for a photo image, as necessary, to change the
* image's size to `width' x `height' pixels.
*
* Results:
* None.
*
* Side effects:
* Storage gets reallocated, for the master and all its instances.
*
*----------------------------------------------------------------------
*/
static void
ImgPhotoSetSize(masterPtr, width, height)
PhotoMaster *masterPtr;
int width, height;
{
unsigned char *newPix24;
int h, offset, pitch;
unsigned char *srcPtr, *destPtr;
XRectangle validBox, clipBox;
TkRegion clipRegion;
PhotoInstance *instancePtr;
if (masterPtr->userWidth > 0) {
width = masterPtr->userWidth;
}
if (masterPtr->userHeight > 0) {
height = masterPtr->userHeight;
}
/*
* We have to trim the valid region if it is currently
* larger than the new image size.
*/
TkClipBox(masterPtr->validRegion, &validBox);
if ((validBox.x + validBox.width > width)
|| (validBox.y + validBox.height > height)) {
clipBox.x = 0;
clipBox.y = 0;
clipBox.width = width;
clipBox.height = height;
clipRegion = TkCreateRegion();
TkUnionRectWithRegion(&clipBox, clipRegion, clipRegion);
TkIntersectRegion(masterPtr->validRegion, clipRegion,
masterPtr->validRegion);
TkDestroyRegion(clipRegion);
TkClipBox(masterPtr->validRegion, &validBox);
}
if ((width != masterPtr->width) || (height != masterPtr->height)
|| (masterPtr->pix24 == NULL)) {
/*
* Reallocate storage for the 24-bit image and copy
* over valid regions.
*/
pitch = width * 3;
newPix24 = (unsigned char *) ckalloc((unsigned) (height * pitch));
/*
* Zero the new array. The dithering code shouldn't read the
* areas outside validBox, but they might be copied to another
* photo image or written to a file.
*/
if ((masterPtr->pix24 != NULL)
&& ((width == masterPtr->width) || (width == validBox.width))) {
if (validBox.y > 0) {
memset((VOID *) newPix24, 0, (size_t) (validBox.y * pitch));
}
h = validBox.y + validBox.height;
if (h < height) {
memset((VOID *) (newPix24 + h * pitch), 0,
(size_t) ((height - h) * pitch));
}
} else {
memset((VOID *) newPix24, 0, (size_t) (height * pitch));
}
if (masterPtr->pix24 != NULL) {
/*
* Copy the common area over to the new array array and
* free the old array.
*/
if (width == masterPtr->width) {
/*
* The region to be copied is contiguous.
*/
offset = validBox.y * pitch;
memcpy((VOID *) (newPix24 + offset),
(VOID *) (masterPtr->pix24 + offset),
(size_t) (validBox.height * pitch));
} else if ((validBox.width > 0) && (validBox.height > 0)) {
/*
* Area to be copied is not contiguous - copy line by line.
*/
destPtr = newPix24 + (validBox.y * width + validBox.x) * 3;
srcPtr = masterPtr->pix24 + (validBox.y * masterPtr->width
+ validBox.x) * 3;
for (h = validBox.height; h > 0; h--) {
memcpy((VOID *) destPtr, (VOID *) srcPtr,
(size_t) (validBox.width * 3));
destPtr += width * 3;
srcPtr += masterPtr->width * 3;
}
}
ckfree((char *) masterPtr->pix24);
}
masterPtr->pix24 = newPix24;
masterPtr->width = width;
masterPtr->height = height;
/*
* Dithering will be correct up to the end of the last
* pre-existing complete scanline.
*/
if ((validBox.x > 0) || (validBox.y > 0)) {
masterPtr->ditherX = 0;
masterPtr->ditherY = 0;
} else if (validBox.width == width) {
if ((int) validBox.height < masterPtr->ditherY) {
masterPtr->ditherX = 0;
masterPtr->ditherY = validBox.height;
}
} else {
if ((masterPtr->ditherY > 0)
|| ((int) validBox.width < masterPtr->ditherX)) {
masterPtr->ditherX = validBox.width;
masterPtr->ditherY = 0;
}
}
}
/*
* Now adjust the sizes of the pixmaps for all of the instances.
*/
for (instancePtr = masterPtr->instancePtr; instancePtr != NULL;
instancePtr = instancePtr->nextPtr) {
ImgPhotoInstanceSetSize(instancePtr);
}
}
/*
*----------------------------------------------------------------------
*
* ImgPhotoInstanceSetSize --
*
* This procedure reallocates the instance pixmap and dithering
* error array for a photo instance, as necessary, to change the
* image's size to `width' x `height' pixels.
*
* Results:
* None.
*
* Side effects:
* Storage gets reallocated, here and in the X server.
*
*----------------------------------------------------------------------
*/
static void
ImgPhotoInstanceSetSize(instancePtr)
PhotoInstance *instancePtr; /* Instance whose size is to be
* changed. */
{
PhotoMaster *masterPtr;
schar *newError;
schar *errSrcPtr, *errDestPtr;
int h, offset;
XRectangle validBox;
Pixmap newPixmap;
masterPtr = instancePtr->masterPtr;
TkClipBox(masterPtr->validRegion, &validBox);
if ((instancePtr->width != masterPtr->width)
|| (instancePtr->height != masterPtr->height)
|| (instancePtr->pixels == None)) {
newPixmap = Tk_GetPixmap(instancePtr->display,
RootWindow(instancePtr->display,
instancePtr->visualInfo.screen),
(masterPtr->width > 0) ? masterPtr->width: 1,
(masterPtr->height > 0) ? masterPtr->height: 1,
instancePtr->visualInfo.depth);
/*
* The following is a gross hack needed to properly support colormaps
* under Windows. Before the pixels can be copied to the pixmap,
* the relevent colormap must be associated with the drawable.
* Normally we can infer this association from the window that
* was used to create the pixmap. However, in this case we're
* using the root window, so we have to be more explicit.
*/
TkSetPixmapColormap(newPixmap, instancePtr->colormap);
if (instancePtr->pixels != None) {
/*
* Copy any common pixels from the old pixmap and free it.
*/
XCopyArea(instancePtr->display, instancePtr->pixels, newPixmap,
instancePtr->gc, validBox.x, validBox.y,
validBox.width, validBox.height, validBox.x, validBox.y);
Tk_FreePixmap(instancePtr->display, instancePtr->pixels);
}
instancePtr->pixels = newPixmap;
}
if ((instancePtr->width != masterPtr->width)
|| (instancePtr->height != masterPtr->height)
|| (instancePtr->error == NULL)) {
newError = (schar *) ckalloc((unsigned)
(masterPtr->height * masterPtr->width * 3 * sizeof(schar)));
/*
* Zero the new array so that we don't get bogus error values
* propagating into areas we dither later.
*/
if ((instancePtr->error != NULL)
&& ((instancePtr->width == masterPtr->width)
|| (validBox.width == masterPtr->width))) {
if (validBox.y > 0) {
memset((VOID *) newError, 0, (size_t)
(validBox.y * masterPtr->width * 3 * sizeof(schar)));
}
h = validBox.y + validBox.height;
if (h < masterPtr->height) {
memset((VOID *) (newError + h * masterPtr->width * 3), 0,
(size_t) ((masterPtr->height - h)
* masterPtr->width * 3 * sizeof(schar)));
}
} else {
memset((VOID *) newError, 0, (size_t)
(masterPtr->height * masterPtr->width * 3 * sizeof(schar)));
}
if (instancePtr->error != NULL) {
/*
* Copy the common area over to the new array
* and free the old array.
*/
if (masterPtr->width == instancePtr->width) {
offset = validBox.y * masterPtr->width * 3;
memcpy((VOID *) (newError + offset),
(VOID *) (instancePtr->error + offset),
(size_t) (validBox.height
* masterPtr->width * 3 * sizeof(schar)));
} else if (validBox.width > 0 && validBox.height > 0) {
errDestPtr = newError
+ (validBox.y * masterPtr->width + validBox.x) * 3;
errSrcPtr = instancePtr->error
+ (validBox.y * instancePtr->width + validBox.x) * 3;
for (h = validBox.height; h > 0; --h) {
memcpy((VOID *) errDestPtr, (VOID *) errSrcPtr,
validBox.width * 3 * sizeof(schar));
errDestPtr += masterPtr->width * 3;
errSrcPtr += instancePtr->width * 3;
}
}
ckfree((char *) instancePtr->error);
}
instancePtr->error = newError;
}
instancePtr->width = masterPtr->width;
instancePtr->height = masterPtr->height;
}
/*
*----------------------------------------------------------------------
*
* IsValidPalette --
*
* This procedure is called to check whether a value given for
* the -palette option is valid for a particular instance
* of a photo image.
*
* Results:
* A boolean value: 1 if the palette is acceptable, 0 otherwise.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static int
IsValidPalette(instancePtr, palette)
PhotoInstance *instancePtr; /* Instance to which the palette
* specification is to be applied. */
char *palette; /* Palette specification string. */
{
int nRed, nGreen, nBlue, mono, numColors;
char *endp;
/*
* First parse the specification: it must be of the form
* %d or %d/%d/%d.
*/
nRed = strtol(palette, &endp, 10);
if ((endp == palette) || ((*endp != 0) && (*endp != '/'))
|| (nRed < 2) || (nRed > 256)) {
return 0;
}
if (*endp == 0) {
mono = 1;
nGreen = nBlue = nRed;
} else {
palette = endp + 1;
nGreen = strtol(palette, &endp, 10);
if ((endp == palette) || (*endp != '/') || (nGreen < 2)
|| (nGreen > 256)) {
return 0;
}
palette = endp + 1;
nBlue = strtol(palette, &endp, 10);
if ((endp == palette) || (*endp != 0) || (nBlue < 2)
|| (nBlue > 256)) {
return 0;
}
mono = 0;
}
switch (instancePtr->visualInfo.class) {
case DirectColor:
case TrueColor:
if ((nRed > (1 << CountBits(instancePtr->visualInfo.red_mask)))
|| (nGreen > (1
<< CountBits(instancePtr->visualInfo.green_mask)))
|| (nBlue > (1
<< CountBits(instancePtr->visualInfo.blue_mask)))) {
return 0;
}
break;
case PseudoColor:
case StaticColor:
numColors = nRed;
if (!mono) {
numColors *= nGreen*nBlue;
}
if (numColors > (1 << instancePtr->visualInfo.depth)) {
return 0;
}
break;
case GrayScale:
case StaticGray:
if (!mono || (nRed > (1 << instancePtr->visualInfo.depth))) {
return 0;
}
break;
}
return 1;
}
/*
*----------------------------------------------------------------------
*
* CountBits --
*
* This procedure counts how many bits are set to 1 in `mask'.
*
* Results:
* The integer number of bits.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static int
CountBits(mask)
pixel mask; /* Value to count the 1 bits in. */
{
int n;
for( n = 0; mask != 0; mask &= mask - 1 )
n++;
return n;
}
/*
*----------------------------------------------------------------------
*
* GetColorTable --
*
* This procedure is called to allocate a table of colormap
* information for an instance of a photo image. Only one such
* table is allocated for all photo instances using the same
* display, colormap, palette and gamma values, so that the
* application need only request a set of colors from the X
* server once for all such photo widgets. This procedure
* maintains a hash table to find previously-allocated
* ColorTables.
*
* Results:
* None.
*
* Side effects:
* A new ColorTable may be allocated and placed in the hash
* table, and have colors allocated for it.
*
*----------------------------------------------------------------------
*/
static void
GetColorTable(instancePtr)
PhotoInstance *instancePtr; /* Instance needing a color table. */
{
ColorTable *colorPtr;
Tcl_HashEntry *entry;
ColorTableId id;
int isNew;
/*
* Look for an existing ColorTable in the hash table.
*/
memset((VOID *) &id, 0, sizeof(id));
id.display = instancePtr->display;
id.colormap = instancePtr->colormap;
id.palette = instancePtr->palette;
id.gamma = instancePtr->gamma;
if (!imgPhotoColorHashInitialized) {
Tcl_InitHashTable(&imgPhotoColorHash, N_COLOR_HASH);
imgPhotoColorHashInitialized = 1;
}
entry = Tcl_CreateHashEntry(&imgPhotoColorHash, (char *) &id, &isNew);
if (!isNew) {
/*
* Re-use the existing entry.
*/
colorPtr = (ColorTable *) Tcl_GetHashValue(entry);
} else {
/*
* No color table currently available; need to make one.
*/
colorPtr = (ColorTable *) ckalloc(sizeof(ColorTable));
/*
* The following line of code should not normally be needed due
* to the assignment in the following line. However, it compensates
* for bugs in some compilers (HP, for example) where
* sizeof(ColorTable) is 24 but the assignment only copies 20 bytes,
* leaving 4 bytes uninitialized; these cause problems when using
* the id for lookups in imgPhotoColorHash, and can result in
* core dumps.
*/
memset((VOID *) &colorPtr->id, 0<