shared_source/c_tk_base_7_5_w_mods/tkimage.c

/* $Header$ */

/* 
 * tkImage.c --
 *
 *      This module implements the image protocol, which allows lots
 *      of different kinds of images to be used in lots of different
 *      widgets.
 *
 * Copyright (c) 1994 The Regents of the University of California.
 * Copyright (c) 1994-1997 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tkimage.c,v 1.1.1.1 2001/06/13 05:02:12 dtashley Exp $
 */

#include "tkInt.h"
#include "tkPort.h"

/*
 * Each call to Tk_GetImage returns a pointer to one of the following
 * structures, which is used as a token by clients (widgets) that
 * display images.
 */

typedef struct Image {
    Tk_Window tkwin;            /* Window passed to Tk_GetImage (needed to
                                 * "re-get" the image later if the manager
                                 * changes). */
    Display *display;           /* Display for tkwin.  Needed because when
                                 * the image is eventually freed tkwin may
                                 * not exist anymore. */
    struct ImageMaster *masterPtr;
                                /* Master for this image (identifiers image
                                 * manager, for example). */
    ClientData instanceData;
                                /* One word argument to pass to image manager
                                 * when dealing with this image instance. */
    Tk_ImageChangedProc *changeProc;
                                /* Code in widget to call when image changes
                                 * in a way that affects redisplay. */
    ClientData widgetClientData;
                                /* Argument to pass to changeProc. */
    struct Image *nextPtr;      /* Next in list of all image instances
                                 * associated with the same name. */

} Image;

/*
 * For each image master there is one of the following structures,
 * which represents a name in the image table and all of the images
 * instantiated from it.  Entries in mainPtr->imageTable point to
 * these structures.
 */

typedef struct ImageMaster {
    Tk_ImageType *typePtr;      /* Information about image type.  NULL means
                                 * that no image manager owns this image:  the
                                 * image was deleted. */
    ClientData masterData;      /* One-word argument to pass to image mgr
                                 * when dealing with the master, as opposed
                                 * to instances. */
    int width, height;          /* Last known dimensions for image. */
    Tcl_HashTable *tablePtr;    /* Pointer to hash table containing image
                                 * (the imageTable field in some TkMainInfo
                                 * structure). */
    Tcl_HashEntry *hPtr;        /* Hash entry in mainPtr->imageTable for
                                 * this structure (used to delete the hash
                                 * entry). */
    Image *instancePtr;         /* Pointer to first in list of instances
                                 * derived from this name. */
} ImageMaster;

typedef struct ThreadSpecificData {
    Tk_ImageType *imageTypeList;/* First in a list of all known image 
                                 * types. */  
    Tk_ImageType *oldImageTypeList;/* First in a list of all known old-style image 
                                 * types. */  
} ThreadSpecificData;           
static Tcl_ThreadDataKey dataKey;

/*
 * Prototypes for local procedures:
 */

static void             DeleteImage _ANSI_ARGS_((ImageMaster *masterPtr));

/*
 *----------------------------------------------------------------------
 *
 * Tk_CreateOldImageType, Tk_CreateImageType --
 *
 *      This procedure is invoked by an image manager to tell Tk about
 *      a new kind of image and the procedures that manage the new type.
 *      The procedure is typically invoked during Tcl_AppInit.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The new image type is entered into a table used in the "image
 *      create" command.
 *
 *----------------------------------------------------------------------
 */

void
Tk_CreateOldImageType(typePtr)
    Tk_ImageType *typePtr;      /* Structure describing the type.  All of
                                 * the fields except "nextPtr" must be filled
                                 * in by caller.  Must not have been passed
                                 * to Tk_CreateImageType previously. */
{
    ThreadSpecificData *tsdPtr = (ThreadSpecificData *) 
            Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));

    typePtr->nextPtr = tsdPtr->oldImageTypeList;
    tsdPtr->oldImageTypeList = typePtr;
}

void
Tk_CreateImageType(typePtr)
    Tk_ImageType *typePtr;      /* Structure describing the type.  All of
                                 * the fields except "nextPtr" must be filled
                                 * in by caller.  Must not have been passed
                                 * to Tk_CreateImageType previously. */
{
    ThreadSpecificData *tsdPtr = (ThreadSpecificData *) 
            Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));

    typePtr->nextPtr = tsdPtr->imageTypeList;
    tsdPtr->imageTypeList = typePtr;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_ImageObjCmd --
 *
 *      This procedure is invoked to process the "image" Tcl command.
 *      See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

int
Tk_ImageObjCmd(clientData, interp, objc, objv)
    ClientData clientData;      /* Main window associated with interpreter. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument strings. */
{
    static char *imageOptions[] = {
        "create", "delete", "height", "names", "type", "types", "width",
        (char *) NULL
    };
    enum options {
        IMAGE_CREATE, IMAGE_DELETE, IMAGE_HEIGHT, IMAGE_NAMES,
        IMAGE_TYPE, IMAGE_TYPES, IMAGE_WIDTH
    };
    TkWindow *winPtr = (TkWindow *) clientData;
    int i, new, firstOption,  index;
    Tk_ImageType *typePtr;
    ImageMaster *masterPtr;
    Image *imagePtr;
    Tcl_HashEntry *hPtr;
    Tcl_HashSearch search;
    char idString[16 + TCL_INTEGER_SPACE], *name;
    TkDisplay *dispPtr = winPtr->dispPtr;
    ThreadSpecificData *tsdPtr = (ThreadSpecificData *) 
            Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));

    if (objc < 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "option ?args?");
        return TCL_ERROR;
    }

    if (Tcl_GetIndexFromObj(interp, objv[1], imageOptions, "option", 0,
            &index) != TCL_OK) {
        return TCL_ERROR;
    }
    switch ((enum options) index) {
        case IMAGE_CREATE: {
            char *arg;
            Tcl_Obj **args;
            int oldimage = 0;
            if (objc < 3) {
                Tcl_WrongNumArgs(interp, 2, objv, "type ?name? ?options?");
                return TCL_ERROR;
            }

            /*
             * Look up the image type.
             */

            arg = Tcl_GetString(objv[2]);
            for (typePtr = tsdPtr->imageTypeList; typePtr != NULL;
                 typePtr = typePtr->nextPtr) {
                if ((*arg == typePtr->name[0])
                        && (strcmp(arg, typePtr->name) == 0)) {
                    break;
                }
            }
            if (typePtr == NULL) {
                oldimage = 1;
                for (typePtr = tsdPtr->oldImageTypeList; typePtr != NULL;
                     typePtr = typePtr->nextPtr) {
                    if ((*arg == typePtr->name[0])
                            && (strcmp(arg, typePtr->name) == 0)) {
                        break;
                    }
                }
            }
            if (typePtr == NULL) {
                Tcl_AppendResult(interp, "image type \"", arg,
                        "\" doesn't exist", (char *) NULL);
                return TCL_ERROR;
            }

            /*
             * Figure out a name to use for the new image.
             */

            if ((objc == 3) || (*(arg = Tcl_GetString(objv[3])) == '-')) {
                dispPtr->imageId++;
                sprintf(idString, "image%d", dispPtr->imageId);
                name = idString;
                firstOption = 3;
            } else {
                name = arg;
                firstOption = 4;
            }

            /*
             * Create the data structure for the new image.
             */

            hPtr = Tcl_CreateHashEntry(&winPtr->mainPtr->imageTable,
                    name, &new);
            if (new) {
                masterPtr = (ImageMaster *) ckalloc(sizeof(ImageMaster));
                masterPtr->typePtr = NULL;
                masterPtr->masterData = NULL;
                masterPtr->width = masterPtr->height = 1;
                masterPtr->tablePtr = &winPtr->mainPtr->imageTable;
                masterPtr->hPtr = hPtr;
                masterPtr->instancePtr = NULL;
                Tcl_SetHashValue(hPtr, masterPtr);
            } else {
                /*
                 * An image already exists by this name.  Disconnect the
                 * instances from the master.
                 */

                masterPtr = (ImageMaster *) Tcl_GetHashValue(hPtr);
                if (masterPtr->typePtr != NULL) {
                    for (imagePtr = masterPtr->instancePtr; imagePtr != NULL;
                         imagePtr = imagePtr->nextPtr) {
                        (*masterPtr->typePtr->freeProc)(
                            imagePtr->instanceData, imagePtr->display);
                        (*imagePtr->changeProc)(imagePtr->widgetClientData,
                                0, 0, masterPtr->width, masterPtr->height,
                                masterPtr->width, masterPtr->height);
                    }
                    (*masterPtr->typePtr->deleteProc)(masterPtr->masterData);
                    masterPtr->typePtr = NULL;
                }
            }

            /*
             * Call the image type manager so that it can perform its own
             * initialization, then re-"get" for any existing instances of
             * the image.
             */

            objv += firstOption;
            objc -= firstOption;
            args = (Tcl_Obj **) objv;
            if (oldimage) {
                int i;
                args = (Tcl_Obj **) ckalloc((objc+1) * sizeof(char *));
                for (i = 0; i < objc; i++) {
                    args[i] = (Tcl_Obj *) Tcl_GetString(objv[i]);
                }
                args[objc] = NULL;
            }
            if ((*typePtr->createProc)(interp, name, objc,
                    args, typePtr, (Tk_ImageMaster) masterPtr,
                    &masterPtr->masterData) != TCL_OK) {
                DeleteImage(masterPtr);
                if (oldimage) {
                    ckfree((char *) args);
                }
                return TCL_ERROR;
            }
            if (oldimage) {
                ckfree((char *) args);
            }
            masterPtr->typePtr = typePtr;
            for (imagePtr = masterPtr->instancePtr; imagePtr != NULL;
                 imagePtr = imagePtr->nextPtr) {
                imagePtr->instanceData = (*typePtr->getProc)(
                    imagePtr->tkwin, masterPtr->masterData);
            }
            Tcl_SetResult(interp,
                    Tcl_GetHashKey(&winPtr->mainPtr->imageTable, hPtr),
                    TCL_STATIC);
            break;
        }
        case IMAGE_DELETE: {
            for (i = 2; i < objc; i++) {
                char *arg = Tcl_GetString(objv[i]);
                hPtr = Tcl_FindHashEntry(&winPtr->mainPtr->imageTable, arg);
                if (hPtr == NULL) {
                    Tcl_AppendResult(interp, "image \"", arg,
                            "\" doesn't exist", (char *) NULL);
                    return TCL_ERROR;
                }
                masterPtr = (ImageMaster *) Tcl_GetHashValue(hPtr);
                DeleteImage(masterPtr);
            }
            break;
        }
        case IMAGE_HEIGHT: {    
            char *arg;
            if (objc != 3) {
                Tcl_WrongNumArgs(interp, 2, objv, "name");
                return TCL_ERROR;
            }
            arg = Tcl_GetString(objv[2]);
            hPtr = Tcl_FindHashEntry(&winPtr->mainPtr->imageTable, arg);
            if (hPtr == NULL) {
                Tcl_AppendResult(interp, "image \"", arg,
                        "\" doesn't exist", (char *) NULL);
                return TCL_ERROR;
            }
            masterPtr = (ImageMaster *) Tcl_GetHashValue(hPtr);
            Tcl_SetIntObj(Tcl_GetObjResult(interp), masterPtr->height);
            break;
        }
        case IMAGE_NAMES: {
            if (objc != 2) {
                Tcl_WrongNumArgs(interp, 2, objv, NULL);
                return TCL_ERROR;
            }
            for (hPtr = Tcl_FirstHashEntry(&winPtr->mainPtr->imageTable, &search);
                 hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
                Tcl_AppendElement(interp, Tcl_GetHashKey(
                    &winPtr->mainPtr->imageTable, hPtr));
            }
            break;
        }
        case IMAGE_TYPE: {
            char *arg;
            if (objc != 3) {
                Tcl_WrongNumArgs(interp, 2, objv, "name");
                return TCL_ERROR;
            }
            arg = Tcl_GetString(objv[2]);
            hPtr = Tcl_FindHashEntry(&winPtr->mainPtr->imageTable, arg);
            if (hPtr == NULL) {
                Tcl_AppendResult(interp, "image \"", arg,
                        "\" doesn't exist", (char *) NULL);
                return TCL_ERROR;
            }
            masterPtr = (ImageMaster *) Tcl_GetHashValue(hPtr);
            if (masterPtr->typePtr != NULL) {
                Tcl_SetResult(interp, masterPtr->typePtr->name, TCL_STATIC);
            }
            break;
        }
        case IMAGE_TYPES: {
            if (objc != 2) {
                Tcl_WrongNumArgs(interp, 2, objv, NULL);
                return TCL_ERROR;
            }
            for (typePtr = tsdPtr->imageTypeList; typePtr != NULL;
                 typePtr = typePtr->nextPtr) {
                Tcl_AppendElement(interp, typePtr->name);
            }
            for (typePtr = tsdPtr->oldImageTypeList; typePtr != NULL;
                 typePtr = typePtr->nextPtr) {
                Tcl_AppendElement(interp, typePtr->name);
            }
            break;
        }
        case IMAGE_WIDTH: {
            char *arg;
            if (objc != 3) {
                Tcl_WrongNumArgs(interp, 2, objv, "name");
                return TCL_ERROR;
            }
            arg = Tcl_GetString(objv[2]);
            hPtr = Tcl_FindHashEntry(&winPtr->mainPtr->imageTable, arg);
            if (hPtr == NULL) {
                Tcl_AppendResult(interp, "image \"", arg,
                        "\" doesn't exist", (char *) NULL);
                return TCL_ERROR;
            }
            masterPtr = (ImageMaster *) Tcl_GetHashValue(hPtr);
            Tcl_SetIntObj(Tcl_GetObjResult(interp), masterPtr->width);
            break;
        }
    }
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_ImageChanged --
 *
 *      This procedure is called by an image manager whenever something
 *      has happened that requires the image to be redrawn (some of its
 *      pixels have changed, or its size has changed).
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Any widgets that display the image are notified so that they
 *      can redisplay themselves as appropriate.
 *
 *----------------------------------------------------------------------
 */

void
Tk_ImageChanged(imageMaster, x, y, width, height, imageWidth,
        imageHeight)
    Tk_ImageMaster imageMaster; /* Image that needs redisplay. */
    int x, y;                   /* Coordinates of upper-left pixel of
                                 * region of image that needs to be
                                 * redrawn. */
    int width, height;          /* Dimensions (in pixels) of region of
                                 * image to redraw.  If either dimension
                                 * is zero then the image doesn't need to
                                 * be redrawn (perhaps all that happened is
                                 * that its size changed). */
    int imageWidth, imageHeight;/* New dimensions of image. */
{
    ImageMaster *masterPtr = (ImageMaster *) imageMaster;
    Image *imagePtr;

    masterPtr->width = imageWidth;
    masterPtr->height = imageHeight;
    for (imagePtr = masterPtr->instancePtr; imagePtr != NULL;
         imagePtr = imagePtr->nextPtr) {
        (*imagePtr->changeProc)(imagePtr->widgetClientData, x, y,
                width, height, imageWidth, imageHeight);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_NameOfImage --
 *
 *      Given a token for an image master, this procedure returns
 *      the name of the image.
 *
 * Results:
 *      The return value is the string name for imageMaster.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */

char *
Tk_NameOfImage(imageMaster)
    Tk_ImageMaster imageMaster;         /* Token for image. */
{
    ImageMaster *masterPtr = (ImageMaster *) imageMaster;

    return Tcl_GetHashKey(masterPtr->tablePtr, masterPtr->hPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_GetImage --
 *
 *      This procedure is invoked by a widget when it wants to use
 *      a particular image in a particular window.
 *
 * Results:
 *      The return value is a token for the image.  If there is no image
 *      by the given name, then NULL is returned and an error message is
 *      left in the interp's result.
 *
 * Side effects:
 *      Tk records the fact that the widget is using the image, and
 *      it will invoke changeProc later if the widget needs redisplay
 *      (i.e. its size changes or some of its pixels change).  The
 *      caller must eventually invoke Tk_FreeImage when it no longer
 *      needs the image.
 *
 *----------------------------------------------------------------------
 */

Tk_Image
Tk_GetImage(interp, tkwin, name, changeProc, clientData)
    Tcl_Interp *interp;         /* Place to leave error message if image
                                 * can't be found. */
    Tk_Window tkwin;            /* Token for window in which image will
                                 * be used. */
    char *name;                 /* Name of desired image. */
    Tk_ImageChangedProc *changeProc;
                                /* Procedure to invoke when redisplay is
                                 * needed because image's pixels or size
                                 * changed. */
    ClientData clientData;      /* One-word argument to pass to damageProc. */
{
    Tcl_HashEntry *hPtr;
    ImageMaster *masterPtr;
    Image *imagePtr;

    hPtr = Tcl_FindHashEntry(&((TkWindow *) tkwin)->mainPtr->imageTable, name);
    if (hPtr == NULL) {
        goto noSuchImage;
    }
    masterPtr = (ImageMaster *) Tcl_GetHashValue(hPtr);
    if (masterPtr->typePtr == NULL) {
        goto noSuchImage;
    }
    imagePtr = (Image *) ckalloc(sizeof(Image));
    imagePtr->tkwin = tkwin;
    imagePtr->display = Tk_Display(tkwin);
    imagePtr->masterPtr = masterPtr;
    imagePtr->instanceData =
            (*masterPtr->typePtr->getProc)(tkwin, masterPtr->masterData);
    imagePtr->changeProc = changeProc;
    imagePtr->widgetClientData = clientData;
    imagePtr->nextPtr = masterPtr->instancePtr;
    masterPtr->instancePtr = imagePtr;
    return (Tk_Image) imagePtr;

    noSuchImage:
    Tcl_AppendResult(interp, "image \"", name, "\" doesn't exist",
            (char *) NULL);
    return NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_FreeImage --
 *
 *      This procedure is invoked by a widget when it no longer needs
 *      an image acquired by a previous call to Tk_GetImage.  For each
 *      call to Tk_GetImage there must be exactly one call to Tk_FreeImage.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The association between the image and the widget is removed.
 *
 *----------------------------------------------------------------------
 */

void
Tk_FreeImage(image)
    Tk_Image image;             /* Token for image that is no longer
                                 * needed by a widget. */
{
    Image *imagePtr = (Image *) image;
    ImageMaster *masterPtr = imagePtr->masterPtr;
    Image *prevPtr;

    /*
     * Clean up the particular instance.
     */

    if (masterPtr->typePtr != NULL) {
        (*masterPtr->typePtr->freeProc)(imagePtr->instanceData,
                imagePtr->display);
    }
    prevPtr = masterPtr->instancePtr;
    if (prevPtr == imagePtr) {
        masterPtr->instancePtr = imagePtr->nextPtr;
    } else {
        while (prevPtr->nextPtr != imagePtr) {
            prevPtr = prevPtr->nextPtr;
        }
        prevPtr->nextPtr = imagePtr->nextPtr;
    }
    ckfree((char *) imagePtr);

    /* 
     * If there are no more instances left for the master, and if the
     * master image has been deleted, then delete the master too.
     */

    if ((masterPtr->typePtr == NULL) && (masterPtr->instancePtr == NULL)) {
        Tcl_DeleteHashEntry(masterPtr->hPtr);
        ckfree((char *) masterPtr);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_PostscriptImage --
 *
 *      This procedure is called by widgets that contain images in order
 *      to redisplay an image on the screen or an off-screen pixmap.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The image's manager is notified, and it redraws the desired
 *      portion of the image before returning.
 *
 *----------------------------------------------------------------------
 */

int
Tk_PostscriptImage(image, interp, tkwin, psinfo, x, y, width, height, prepass)
    Tk_Image image;             /* Token for image to redisplay. */
    Tcl_Interp *interp;
    Tk_Window tkwin;
    Tk_PostscriptInfo psinfo;   /* postscript info */
    int x, y;                   /* Upper-left pixel of region in image that
                                 * needs to be redisplayed. */
    int width, height;          /* Dimensions of region to redraw. */
    int prepass;
{
    Image *imagePtr = (Image *) image;
    int result;
    XImage *ximage;
    Pixmap pmap;
    GC newGC;
    XGCValues gcValues;

    if (imagePtr->masterPtr->typePtr == NULL) {
        /*
         * No master for image, so nothing to display on postscript.
         */
        return TCL_OK;
    }

    /*
     * Check if an image specific postscript-generation function
     * exists; otherwise go on with generic code.
     */

    if (imagePtr->masterPtr->typePtr->postscriptProc != NULL) {
        return (*imagePtr->masterPtr->typePtr->postscriptProc)(
            imagePtr->masterPtr->masterData, interp, tkwin, psinfo,
            x, y, width, height, prepass);
    }

    if (prepass) {
        return TCL_OK;
    }

    /*
     * Create a Pixmap, tell the image to redraw itself there, and then
     * generate an XImage from the Pixmap.  We can then read pixel 
     * values out of the XImage.
     */

    pmap = Tk_GetPixmap(Tk_Display(tkwin), Tk_WindowId(tkwin),
                        width, height, Tk_Depth(tkwin));

    gcValues.foreground = WhitePixelOfScreen(Tk_Screen(tkwin));
    newGC = Tk_GetGC(tkwin, GCForeground, &gcValues);
    if (newGC != None) {
        XFillRectangle(Tk_Display(tkwin), pmap, newGC,
                0, 0, (unsigned int)width, (unsigned int)height);
        Tk_FreeGC(Tk_Display(tkwin), newGC);
    }

    Tk_RedrawImage(image, x, y, width, height, pmap, 0, 0);

    ximage = XGetImage(Tk_Display(tkwin), pmap, 0, 0,
            (unsigned int)width, (unsigned int)height, AllPlanes, ZPixmap);

    Tk_FreePixmap(Tk_Display(tkwin), pmap);
    
    if (ximage == NULL) {
        /* The XGetImage() function is apparently not
         * implemented on this system. Just ignore it.
         */
        return TCL_OK;
    }
    result = TkPostscriptImage(interp, tkwin, psinfo, ximage, x, y,
            width, height);

    XDestroyImage(ximage);
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_RedrawImage --
 *
 *      This procedure is called by widgets that contain images in order
 *      to redisplay an image on the screen or an off-screen pixmap.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The image's manager is notified, and it redraws the desired
 *      portion of the image before returning.
 *
 *----------------------------------------------------------------------
 */

void
Tk_RedrawImage(image, imageX, imageY, width, height, drawable,
        drawableX, drawableY)
    Tk_Image image;             /* Token for image to redisplay. */
    int imageX, imageY;         /* Upper-left pixel of region in image that
                                 * needs to be redisplayed. */
    int width, height;          /* Dimensions of region to redraw. */
    Drawable drawable;          /* Drawable in which to display image
                                 * (window or pixmap).  If this is a pixmap,
                                 * it must have the same depth as the window
                                 * used in the Tk_GetImage call for the
                                 * image. */
    int drawableX, drawableY;   /* Coordinates in drawable that correspond
                                 * to imageX and imageY. */
{
    Image *imagePtr = (Image *) image;

    if (imagePtr->masterPtr->typePtr == NULL) {
        /*
         * No master for image, so nothing to display.
         */

        return;
    }

    /*
     * Clip the redraw area to the area of the image.
     */

    if (imageX < 0) {
        width += imageX;
        drawableX -= imageX;
        imageX = 0;
    }
    if (imageY < 0) {
        height += imageY;
        drawableY -= imageY;
        imageY = 0;
    }
    if ((imageX + width) > imagePtr->masterPtr->width) {
        width = imagePtr->masterPtr->width - imageX;
    }
    if ((imageY + height) > imagePtr->masterPtr->height) {
        height = imagePtr->masterPtr->height - imageY;
    }
    (*imagePtr->masterPtr->typePtr->displayProc)(
            imagePtr->instanceData, imagePtr->display, drawable,
            imageX, imageY, width, height, drawableX, drawableY);
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_SizeOfImage --
 *
 *      This procedure returns the current dimensions of an image.
 *
 * Results:
 *      The width and height of the image are returned in *widthPtr
 *      and *heightPtr.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */

void
Tk_SizeOfImage(image, widthPtr, heightPtr)
    Tk_Image image;             /* Token for image whose size is wanted. */
    int *widthPtr;              /* Return width of image here. */
    int *heightPtr;             /* Return height of image here. */
{
    Image *imagePtr = (Image *) image;

    *widthPtr = imagePtr->masterPtr->width;
    *heightPtr = imagePtr->masterPtr->height;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_DeleteImage --
 *
 *      Given the name of an image, this procedure destroys the
 *      image.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The image is destroyed; existing instances will display as
 *      blank areas.  If no such image exists then the procedure does
 *      nothing.
 *
 *----------------------------------------------------------------------
 */

void
Tk_DeleteImage(interp, name)
    Tcl_Interp *interp;         /* Interpreter in which the image was
                                 * created. */
    char *name;                 /* Name of image. */
{
    Tcl_HashEntry *hPtr;
    TkWindow *winPtr;

    winPtr = (TkWindow *) Tk_MainWindow(interp);
    if (winPtr == NULL) {
        return;
    }
    hPtr = Tcl_FindHashEntry(&winPtr->mainPtr->imageTable, name);
    if (hPtr == NULL) {
        return;
    }
    DeleteImage((ImageMaster *) Tcl_GetHashValue(hPtr));
}

/*
 *----------------------------------------------------------------------
 *
 * DeleteImage --
 *
 *      This procedure is responsible for deleting an image.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The connection is dropped between instances of this image and
 *      an image master.  Image instances will redisplay themselves
 *      as empty areas, but existing instances will not be deleted.
 *
 *----------------------------------------------------------------------
 */

static void
DeleteImage(masterPtr)
    ImageMaster *masterPtr;     /* Pointer to main data structure for image. */
{
    Image *imagePtr;
    Tk_ImageType *typePtr;

    typePtr = masterPtr->typePtr;
    masterPtr->typePtr = NULL;
    if (typePtr != NULL) {
        for (imagePtr = masterPtr->instancePtr; imagePtr != NULL;
                imagePtr = imagePtr->nextPtr) {
           (*typePtr->freeProc)(imagePtr->instanceData,
                   imagePtr->display);
           (*imagePtr->changeProc)(imagePtr->widgetClientData, 0, 0,
                    masterPtr->width, masterPtr->height, masterPtr->width,
                    masterPtr->height);
        }
        (*typePtr->deleteProc)(masterPtr->masterData);
    }
    if (masterPtr->instancePtr == NULL) {
        Tcl_DeleteHashEntry(masterPtr->hPtr);
        ckfree((char *) masterPtr);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TkDeleteAllImages --
 *
 *      This procedure is called when an application is deleted.  It
 *      calls back all of the managers for all images so that they
 *      can cleanup, then it deletes all of Tk's internal information
 *      about images.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      All information for all images gets deleted.
 *
 *----------------------------------------------------------------------
 */

void
TkDeleteAllImages(mainPtr)
    TkMainInfo *mainPtr;        /* Structure describing application that is
                                 * going away. */
{
    Tcl_HashSearch search;
    Tcl_HashEntry *hPtr;
    ImageMaster *masterPtr;

    for (hPtr = Tcl_FirstHashEntry(&mainPtr->imageTable, &search);
            hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
        masterPtr = (ImageMaster *) Tcl_GetHashValue(hPtr);
        DeleteImage(masterPtr);
    }
    Tcl_DeleteHashTable(&mainPtr->imageTable);
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_GetImageMasterData --
 *
 *      Given the name of an image, this procedure returns the type
 *      of the image and the clientData associated with its master.
 *
 * Results:
 *      If there is no image by the given name, then NULL is returned
 *      and a NULL value is stored at *typePtrPtr.  Otherwise the return
 *      value is the clientData returned by the createProc when the
 *      image was created and a pointer to the type structure for the
 *      image is stored at *typePtrPtr.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */

ClientData
Tk_GetImageMasterData(interp, name, typePtrPtr)
    Tcl_Interp *interp;         /* Interpreter in which the image was
                                 * created. */
    char *name;                 /* Name of image. */
    Tk_ImageType **typePtrPtr;  /* Points to location to fill in with
                                 * pointer to type information for image. */
{
    Tcl_HashEntry *hPtr;
    TkWindow *winPtr;
    ImageMaster *masterPtr;

    winPtr = (TkWindow *) Tk_MainWindow(interp);
    hPtr = Tcl_FindHashEntry(&winPtr->mainPtr->imageTable, name);
    if (hPtr == NULL) {
        *typePtrPtr = NULL;
        return NULL;
    }
    masterPtr = (ImageMaster *) Tcl_GetHashValue(hPtr);
    *typePtrPtr = masterPtr->typePtr;
    return masterPtr->masterData;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_SetTSOrigin --
 *
 *      Set the pattern origin of the tile to a common point (i.e. the
 *      origin (0,0) of the top level window) so that tiles from two
 *      different widgets will match up.  This done by setting the
 *      GCTileStipOrigin field is set to the translated origin of the
 *      toplevel window in the hierarchy.
 *
 * Results:
 *      None.
 *
 * Side Effects:
 *      The GCTileStipOrigin is reset in the GC.  This will cause the
 *      tile origin to change when the GC is used for drawing.
 *
 *----------------------------------------------------------------------
 */
/*ARGSUSED*/
void
Tk_SetTSOrigin(tkwin, gc, x, y)
    Tk_Window tkwin;
    GC gc;
    int x, y;
{
    while (!Tk_IsTopLevel(tkwin)) {
        x -= Tk_X(tkwin) + Tk_Changes(tkwin)->border_width;
        y -= Tk_Y(tkwin) + Tk_Changes(tkwin)->border_width;
        tkwin = Tk_Parent(tkwin);
    }
    XSetTSOrigin(Tk_Display(tkwin), gc, x, y);
}

/* End of tkimage.c */