,
	int x, int y, int width, int height, int prepass);

/*
 * The following structure represents a particular type of image (bitmap, xpm
 * image, etc.). It provides information common to all images of that type,
 * such as the type name and a collection of procedures in the image manager
 * that respond to various events. Each image manager is represented by one of
 * these structures.
 */

struct Tk_ImageType {
    CONST86 char *name;		/* Name of image type. */
    Tk_ImageCreateProc *createProc;
				/* Procedure to call to create a new image of
				 * this type. */
    Tk_ImageGetProc *getProc;	/* Procedure to call the first time
				 * Tk_GetImage is called in a new way (new
				 * visual or screen). */
    Tk_ImageDisplayProc *displayProc;
				/* Call to draw image, in response to
				 * Tk_RedrawImage calls. */
    Tk_ImageFreeProc *freeProc;	/* Procedure to call whenever Tk_FreeImage is
				 * called to release an instance of an
				 * image. */
    Tk_ImageDeleteProc *deleteProc;
				/* Procedure to call to delete image. It will
				 * not be called until after freeProc has been
				 * called for each instance of the image. */
    Tk_ImagePostscriptProc *postscriptProc;
				/* Procedure to call to produce postscript
				 * output for the image. */
    struct Tk_ImageType *nextPtr;
				/* Next in list of all image types currently
				 * known. Filled in by Tk, not by image
				 * manager. */
    char *reserved;		/* reserved for future expansion */
};

/*
 *----------------------------------------------------------------------
 *
 * Additional definitions used to manage images of type "photo".
 *
 *----------------------------------------------------------------------
 */

/*
 * The following type is used to identify a particular photo image to be
 * manipulated:
 */

typedef void *Tk_PhotoHandle;

/*
 * The following structure describes a block of pixels in memory:
 */

typedef struct Tk_PhotoImageBlock {
    unsigned char *pixelPtr;	/* Pointer to the first pixel. */
    int width;			/* Width of block, in pixels. */
    int height;			/* Height of block, in pixels. */
    int pitch;			/* Address difference between corresponding
				 * pixels in successive lines. */
    int pixelSize;		/* Address difference between successive
				 * pixels in the same line. */
    int offset[4];		/* Address differences between the red, green,
				 * blue and alpha components of the pixel and
				 * the pixel as a whole. */
} Tk_PhotoImageBlock;

/*
 * The following values control how blocks are combined into photo images when
 * the alpha component of a pixel is not 255, a.k.a. the compositing rule.
 */

#define TK_PHOTO_COMPOSITE_OVERLAY	0
#define TK_PHOTO_COMPOSITE_SET		1

/*
 * Procedure prototypes and structures used in reading and writing photo
 * images:
 */

typedef struct Tk_PhotoImageFormat Tk_PhotoImageFormat;
#ifdef USE_OLD_IMAGE
typedef int (Tk_ImageFileMatchProc) (Tcl_Channel chan, char *fileName,
	char *formatString, int *widthPtr, int *heightPtr);
typedef int (Tk_ImageStringMatchProc) (char *string, char *formatString,
	int *widthPtr, int *heightPtr);
typedef int (Tk_ImageFileReadProc) (Tcl_Interp *interp, Tcl_Channel chan,
	char *fileName, char *formatString, Tk_PhotoHandle imageHandle,
	int destX, int destY, int width, int height, int srcX, int srcY);
typedef int (Tk_ImageStringReadProc) (Tcl_Interp *interp, char *string,
	char *formatString, Tk_PhotoHandle imageHandle, int destX, int destY,
	int width, int height, int srcX, int srcY);
typedef int (Tk_ImageFileWriteProc) (Tcl_Interp *interp, char *fileName,
	char *formatString, Tk_PhotoImageBlock *blockPtr);
typedef int (Tk_ImageStringWriteProc) (Tcl_Interp *interp,
	Tcl_DString *dataPtr, char *formatString, Tk_PhotoImageBlock *blockPtr);
#else
typedef int (Tk_ImageFileMatchProc) (Tcl_Channel chan, const char *fileName,
	Tcl_Obj *format, int *widthPtr, int *heightPtr, Tcl_Interp *interp);
typedef int (Tk_ImageStringMatchProc) (Tcl_Obj *dataObj, Tcl_Obj *format,
	int *widthPtr, int *heightPtr, Tcl_Interp *interp);
typedef int (Tk_ImageFileReadProc) (Tcl_Interp *interp, Tcl_Channel chan,
	const char *fileName, Tcl_Obj *format, Tk_PhotoHandle imageHandle,
	int destX, int destY, int width, int height, int srcX, int srcY);
typedef int (Tk_ImageStringReadProc) (Tcl_Interp *interp, Tcl_Obj *dataObj,
	Tcl_Obj *format, Tk_PhotoHandle imageHandle, int destX, int destY,
	int width, int height, int srcX, int srcY);
typedef int (Tk_ImageFileWriteProc) (Tcl_Interp *interp, const char *fileName,
	Tcl_Obj *format, Tk_PhotoImageBlock *blockPtr);
typedef int (Tk_ImageStringWriteProc) (Tcl_Interp *interp, Tcl_Obj *format,
	Tk_PhotoImageBlock *blockPtr);
#endif /* USE_OLD_IMAGE */

/*
 * The following structure represents a particular file format for storing
 * images (e.g., PPM, GIF, JPEG, etc.). It provides information to allow image
 * files of that format to be recognized and read into a photo image.
 */

struct Tk_PhotoImageFormat {
    CONST86 char *name;		/* Name of image file format */
    Tk_ImageFileMatchProc *fileMatchProc;
				/* Procedure to call to determine whether an
				 * image file matches this format. */
    Tk_ImageStringMatchProc *stringMatchProc;
				/* Procedure to call to determine whether the
				 * data in a string matches this format. */
    Tk_ImageFileReadProc *fileReadProc;
				/* Procedure to call to read data from an
				 * image file into a photo image. */
    Tk_ImageStringReadProc *stringReadProc;
				/* Procedure to call to read data from a
				 * string into a photo image. */
    Tk_ImageFileWriteProc *fileWriteProc;
				/* Procedure to call to write data from a
				 * photo image to a file. */
    Tk_ImageStringWriteProc *stringWriteProc;
				/* Procedure to call to obtain a string
				 * representation of the data in a photo
				 * image.*/
    struct Tk_PhotoImageFormat *nextPtr;
				/* Next in list of all photo image formats
				 * currently known. Filled in by Tk, not by
				 * image format handler. */
};