shared_source/c_tk_base_7_5_w_mods/tkcanvbmap.c

/* $Header$ */

/* 
 * tkCanvBmap.c --
 *
 *      This file implements bitmap items for canvas widgets.
 *
 * Copyright (c) 1992-1994 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: tkcanvbmap.c,v 1.1.1.1 2001/06/13 04:56:16 dtashley Exp $
 */

#include <stdio.h>
#include "tkInt.h"
#include "tkPort.h"
#include "tkCanvas.h"

/*
 * The structure below defines the record for each bitmap item.
 */

typedef struct BitmapItem  {
    Tk_Item header;             /* Generic stuff that's the same for all
                                 * types.  MUST BE FIRST IN STRUCTURE. */
    double x, y;                /* Coordinates of positioning point for
                                 * bitmap. */
    Tk_Anchor anchor;           /* Where to anchor bitmap relative to
                                 * (x,y). */
    Pixmap bitmap;              /* Bitmap to display in window. */
    Pixmap activeBitmap;        /* Bitmap to display in window. */
    Pixmap disabledBitmap;      /* Bitmap to display in window. */
    XColor *fgColor;            /* Foreground color to use for bitmap. */
    XColor *activeFgColor;      /* Foreground color to use for bitmap. */
    XColor *disabledFgColor;    /* Foreground color to use for bitmap. */
    XColor *bgColor;            /* Background color to use for bitmap. */
    XColor *activeBgColor;      /* Background color to use for bitmap. */
    XColor *disabledBgColor;    /* Background color to use for bitmap. */
    GC gc;                      /* Graphics context to use for drawing
                                 * bitmap on screen. */
} BitmapItem;

/*
 * Information used for parsing configuration specs:
 */

static Tk_CustomOption stateOption = {
    (Tk_OptionParseProc *) TkStateParseProc,
    TkStatePrintProc, (ClientData) 2
};
static Tk_CustomOption tagsOption = {
    (Tk_OptionParseProc *) Tk_CanvasTagsParseProc,
    Tk_CanvasTagsPrintProc, (ClientData) NULL
};

static Tk_ConfigSpec configSpecs[] = {
    {TK_CONFIG_COLOR, "-activebackground", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(BitmapItem, activeBgColor), TK_CONFIG_NULL_OK},
    {TK_CONFIG_BITMAP, "-activebitmap", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(BitmapItem, activeBitmap), TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-activeforeground", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(BitmapItem, activeFgColor), TK_CONFIG_NULL_OK},
    {TK_CONFIG_ANCHOR, "-anchor", (char *) NULL, (char *) NULL,
        "center", Tk_Offset(BitmapItem, anchor), TK_CONFIG_DONT_SET_DEFAULT},
    {TK_CONFIG_COLOR, "-background", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(BitmapItem, bgColor), TK_CONFIG_NULL_OK},
    {TK_CONFIG_BITMAP, "-bitmap", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(BitmapItem, bitmap), TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-disabledbackground", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(BitmapItem, disabledBgColor),
        TK_CONFIG_NULL_OK},
    {TK_CONFIG_BITMAP, "-disabledbitmap", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(BitmapItem, disabledBitmap),
        TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-disabledforeground", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(BitmapItem, disabledFgColor),
        TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-foreground", (char *) NULL, (char *) NULL,
        "black", Tk_Offset(BitmapItem, fgColor), 0},
    {TK_CONFIG_CUSTOM, "-state", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(Tk_Item, state), TK_CONFIG_NULL_OK,
        &stateOption},
    {TK_CONFIG_CUSTOM, "-tags", (char *) NULL, (char *) NULL,
        (char *) NULL, 0, TK_CONFIG_NULL_OK, &tagsOption},
    {TK_CONFIG_END, (char *) NULL, (char *) NULL, (char *) NULL,
        (char *) NULL, 0, 0}
};

/*
 * Prototypes for procedures defined in this file:
 */

static int              BitmapCoords _ANSI_ARGS_((Tcl_Interp *interp,
                            Tk_Canvas canvas, Tk_Item *itemPtr, int argc,
                            Tcl_Obj *CONST argv[]));
static int              BitmapToArea _ANSI_ARGS_((Tk_Canvas canvas,
                            Tk_Item *itemPtr, double *rectPtr));
static double           BitmapToPoint _ANSI_ARGS_((Tk_Canvas canvas,
                            Tk_Item *itemPtr, double *coordPtr));
static int              BitmapToPostscript _ANSI_ARGS_((Tcl_Interp *interp,
                            Tk_Canvas canvas, Tk_Item *itemPtr, int prepass));
static void             ComputeBitmapBbox _ANSI_ARGS_((Tk_Canvas canvas,
                            BitmapItem *bmapPtr));
static int              ConfigureBitmap _ANSI_ARGS_((Tcl_Interp *interp,
                            Tk_Canvas canvas, Tk_Item *itemPtr, int argc,
                            Tcl_Obj *CONST argv[], int flags));
static int              CreateBitmap _ANSI_ARGS_((Tcl_Interp *interp,
                            Tk_Canvas canvas, struct Tk_Item *itemPtr,
                            int argc, Tcl_Obj *CONST argv[]));
static void             DeleteBitmap _ANSI_ARGS_((Tk_Canvas canvas,
                            Tk_Item *itemPtr, Display *display));
static void             DisplayBitmap _ANSI_ARGS_((Tk_Canvas canvas,
                            Tk_Item *itemPtr, Display *display, Drawable dst,
                            int x, int y, int width, int height));
static void             ScaleBitmap _ANSI_ARGS_((Tk_Canvas canvas,
                            Tk_Item *itemPtr, double originX, double originY,
                            double scaleX, double scaleY));
static void             TranslateBitmap _ANSI_ARGS_((Tk_Canvas canvas,
                            Tk_Item *itemPtr, double deltaX, double deltaY));

/*
 * The structures below defines the bitmap item type in terms of
 * procedures that can be invoked by generic item code.
 */

Tk_ItemType tkBitmapType = {
    "bitmap",                           /* name */
    sizeof(BitmapItem),                 /* itemSize */
    CreateBitmap,                       /* createProc */
    configSpecs,                        /* configSpecs */
    ConfigureBitmap,                    /* configureProc */
    BitmapCoords,                       /* coordProc */
    DeleteBitmap,                       /* deleteProc */
    DisplayBitmap,                      /* displayProc */
    TK_CONFIG_OBJS,                     /* flags */
    BitmapToPoint,                      /* pointProc */
    BitmapToArea,                       /* areaProc */
    BitmapToPostscript,                 /* postscriptProc */
    ScaleBitmap,                        /* scaleProc */
    TranslateBitmap,                    /* translateProc */
    (Tk_ItemIndexProc *) NULL,          /* indexProc */
    (Tk_ItemCursorProc *) NULL,         /* icursorProc */
    (Tk_ItemSelectionProc *) NULL,      /* selectionProc */
    (Tk_ItemInsertProc *) NULL,         /* insertProc */
    (Tk_ItemDCharsProc *) NULL,         /* dTextProc */
    (Tk_ItemType *) NULL,               /* nextPtr */
};

/*
 *--------------------------------------------------------------
 *
 * CreateBitmap --
 *
 *      This procedure is invoked to create a new bitmap
 *      item in a canvas.
 *
 * Results:
 *      A standard Tcl return value.  If an error occurred in
 *      creating the item, then an error message is left in
 *      the interp's result;  in this case itemPtr is left uninitialized,
 *      so it can be safely freed by the caller.
 *
 * Side effects:
 *      A new bitmap item is created.
 *
 *--------------------------------------------------------------
 */

static int
CreateBitmap(interp, canvas, itemPtr, argc, argv)
    Tcl_Interp *interp;                 /* Interpreter for error reporting. */
    Tk_Canvas canvas;                   /* Canvas to hold new item. */
    Tk_Item *itemPtr;                   /* Record to hold new item;  header
                                         * has been initialized by caller. */
    int argc;                           /* Number of arguments in argv. */
    Tcl_Obj *CONST argv[];              /* Arguments describing rectangle. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
    int i;

    if (argc==1) {
        i = 1;
    } else {
        char *arg = Tcl_GetStringFromObj(argv[1], NULL);
        if (((argc>1) && (arg[0] == '-')
                && (arg[1] >= 'a') && (arg[1] <= 'z'))) {
            i = 1;
        } else {
            i = 2;
        }
    }

    if (argc < i) {
        Tcl_AppendResult(interp, "wrong # args: should be \"",
                Tk_PathName(Tk_CanvasTkwin(canvas)), " create ",
                itemPtr->typePtr->name, " x y ?options?\"",
                (char *) NULL);
        return TCL_ERROR;
    }

    /*
     * Initialize item's record.
     */

    bmapPtr->anchor = TK_ANCHOR_CENTER;
    bmapPtr->bitmap = None;
    bmapPtr->activeBitmap = None;
    bmapPtr->disabledBitmap = None;
    bmapPtr->fgColor = NULL;
    bmapPtr->activeFgColor = NULL;
    bmapPtr->disabledFgColor = NULL;
    bmapPtr->bgColor = NULL;
    bmapPtr->activeBgColor = NULL;
    bmapPtr->disabledBgColor = NULL;
    bmapPtr->gc = None;

    /*
     * Process the arguments to fill in the item record.
     */

    if ((BitmapCoords(interp, canvas, itemPtr, i, argv) != TCL_OK)) {
        goto error;
    }
    if (ConfigureBitmap(interp, canvas, itemPtr, argc-i, argv+i, 0) == TCL_OK) {
        return TCL_OK;
    }

    error:
    DeleteBitmap(canvas, itemPtr, Tk_Display(Tk_CanvasTkwin(canvas)));
    return TCL_ERROR;
}

/*
 *--------------------------------------------------------------
 *
 * BitmapCoords --
 *
 *      This procedure is invoked to process the "coords" widget
 *      command on bitmap items.  See the user documentation for
 *      details on what it does.
 *
 * Results:
 *      Returns TCL_OK or TCL_ERROR, and sets the interp's result.
 *
 * Side effects:
 *      The coordinates for the given item may be changed.
 *
 *--------------------------------------------------------------
 */

static int
BitmapCoords(interp, canvas, itemPtr, argc, argv)
    Tcl_Interp *interp;                 /* Used for error reporting. */
    Tk_Canvas canvas;                   /* Canvas containing item. */
    Tk_Item *itemPtr;                   /* Item whose coordinates are to be
                                         * read or modified. */
    int argc;                           /* Number of coordinates supplied in
                                         * argv. */
    Tcl_Obj *CONST argv[];              /* Array of coordinates: x1, y1,
                                         * x2, y2, ... */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;

    if (argc == 0) {
        Tcl_Obj *obj = Tcl_NewObj();
        Tcl_Obj *subobj = Tcl_NewDoubleObj(bmapPtr->x);
        Tcl_ListObjAppendElement(interp, obj, subobj);
        subobj = Tcl_NewDoubleObj(bmapPtr->y);
        Tcl_ListObjAppendElement(interp, obj, subobj);
        Tcl_SetObjResult(interp, obj);
    } else if (argc <3) {
        if (argc==1) {
            if (Tcl_ListObjGetElements(interp, argv[0], &argc,
                    (Tcl_Obj ***) &argv) != TCL_OK) {
                return TCL_ERROR;
            } else if (argc != 2) {
                char buf[64 + TCL_INTEGER_SPACE];

                sprintf(buf, "wrong # coordinates: expected 2, got %d", argc);
                Tcl_SetResult(interp, buf, TCL_VOLATILE);
                return TCL_ERROR;
            }
        }
        if ((Tk_CanvasGetCoordFromObj(interp, canvas, argv[0], &bmapPtr->x) != TCL_OK)
                || (Tk_CanvasGetCoordFromObj(interp, canvas, argv[1], &bmapPtr->y)
                    != TCL_OK)) {
            return TCL_ERROR;
        }
        ComputeBitmapBbox(canvas, bmapPtr);
    } else {
        char buf[64 + TCL_INTEGER_SPACE];

        sprintf(buf, "wrong # coordinates: expected 0 or 2, got %d", argc);
        Tcl_SetResult(interp, buf, TCL_VOLATILE);
        return TCL_ERROR;
    }
    return TCL_OK;
}

/*
 *--------------------------------------------------------------
 *
 * ConfigureBitmap --
 *
 *      This procedure is invoked to configure various aspects
 *      of a bitmap item, such as its anchor position.
 *
 * Results:
 *      A standard Tcl result code.  If an error occurs, then
 *      an error message is left in the interp's result.
 *
 * Side effects:
 *      Configuration information may be set for itemPtr.
 *
 *--------------------------------------------------------------
 */

static int
ConfigureBitmap(interp, canvas, itemPtr, argc, argv, flags)
    Tcl_Interp *interp;         /* Used for error reporting. */
    Tk_Canvas canvas;           /* Canvas containing itemPtr. */
    Tk_Item *itemPtr;           /* Bitmap item to reconfigure. */
    int argc;                   /* Number of elements in argv.  */
    Tcl_Obj *CONST argv[];      /* Arguments describing things to configure. */
    int flags;                  /* Flags to pass to Tk_ConfigureWidget. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
    XGCValues gcValues;
    GC newGC;
    Tk_Window tkwin;
    unsigned long mask;
    XColor *fgColor;
    XColor *bgColor;
    Pixmap bitmap;
    Tk_State state;

    tkwin = Tk_CanvasTkwin(canvas);
    if (Tk_ConfigureWidget(interp, tkwin, configSpecs, argc, (char **) argv,
            (char *) bmapPtr, flags|TK_CONFIG_OBJS) != TCL_OK) {
        return TCL_ERROR;
    }

    /*
     * A few of the options require additional processing, such as those
     * that determine the graphics context.
     */

    state = itemPtr->state;

    if (bmapPtr->activeFgColor!=NULL ||
            bmapPtr->activeBgColor!=NULL ||
            bmapPtr->activeBitmap!=None) {
        itemPtr->redraw_flags |= TK_ITEM_STATE_DEPENDANT;
    } else {
        itemPtr->redraw_flags &= ~TK_ITEM_STATE_DEPENDANT;
    }

    if(state == TK_STATE_NULL) {
        state = ((TkCanvas *)canvas)->canvas_state;
    }
    if (state==TK_STATE_HIDDEN) {
        ComputeBitmapBbox(canvas, bmapPtr);
        return TCL_OK;  
    }
    fgColor = bmapPtr->fgColor;
    bgColor = bmapPtr->bgColor;
    bitmap = bmapPtr->bitmap;
    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
        if (bmapPtr->activeFgColor!=NULL) {
            fgColor = bmapPtr->activeFgColor;
        }
        if (bmapPtr->activeBgColor!=NULL) {
            bgColor = bmapPtr->activeBgColor;
        }
        if (bmapPtr->activeBitmap!=None) {
            bitmap = bmapPtr->activeBitmap;
        }
    } else if (state==TK_STATE_DISABLED) {
        if (bmapPtr->disabledFgColor!=NULL) {
            fgColor = bmapPtr->disabledFgColor;
        }
        if (bmapPtr->disabledBgColor!=NULL) {
            bgColor = bmapPtr->disabledBgColor;
        }
        if (bmapPtr->disabledBitmap!=None) {
            bitmap = bmapPtr->disabledBitmap;
        }
    }

    if (state==TK_STATE_DISABLED || bitmap == None) {
        ComputeBitmapBbox(canvas, bmapPtr);
        return TCL_OK;
    }

    gcValues.foreground = fgColor->pixel;
    mask = GCForeground;
    if (bgColor != NULL) {
        gcValues.background = bgColor->pixel;
        mask |= GCBackground;
    } else {
        gcValues.clip_mask = bitmap;
        mask |= GCClipMask;
    }
    if (bitmap == None) {
        newGC = None;
    } else {
        newGC = Tk_GetGC(tkwin, mask, &gcValues);
    }
    if (bmapPtr->gc != None) {
        Tk_FreeGC(Tk_Display(tkwin), bmapPtr->gc);
    }
    bmapPtr->gc = newGC;

    ComputeBitmapBbox(canvas, bmapPtr);

    return TCL_OK;
}

/*
 *--------------------------------------------------------------
 *
 * DeleteBitmap --
 *
 *      This procedure is called to clean up the data structure
 *      associated with a bitmap item.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Resources associated with itemPtr are released.
 *
 *--------------------------------------------------------------
 */

static void
DeleteBitmap(canvas, itemPtr, display)
    Tk_Canvas canvas;                   /* Info about overall canvas widget. */
    Tk_Item *itemPtr;                   /* Item that is being deleted. */
    Display *display;                   /* Display containing window for
                                         * canvas. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;

    if (bmapPtr->bitmap != None) {
        Tk_FreeBitmap(display, bmapPtr->bitmap);
    }
    if (bmapPtr->activeBitmap != None) {
        Tk_FreeBitmap(display, bmapPtr->activeBitmap);
    }
    if (bmapPtr->disabledBitmap != None) {
        Tk_FreeBitmap(display, bmapPtr->disabledBitmap);
    }
    if (bmapPtr->fgColor != NULL) {
        Tk_FreeColor(bmapPtr->fgColor);
    }
    if (bmapPtr->activeFgColor != NULL) {
        Tk_FreeColor(bmapPtr->activeFgColor);
    }
    if (bmapPtr->disabledFgColor != NULL) {
        Tk_FreeColor(bmapPtr->disabledFgColor);
    }
    if (bmapPtr->bgColor != NULL) {
        Tk_FreeColor(bmapPtr->bgColor);
    }
    if (bmapPtr->activeBgColor != NULL) {
        Tk_FreeColor(bmapPtr->activeBgColor);
    }
    if (bmapPtr->disabledBgColor != NULL) {
        Tk_FreeColor(bmapPtr->disabledBgColor);
    }
    if (bmapPtr->gc != NULL) {
        Tk_FreeGC(display, bmapPtr->gc);
    }
}

/*
 *--------------------------------------------------------------
 *
 * ComputeBitmapBbox --
 *
 *      This procedure is invoked to compute the bounding box of
 *      all the pixels that may be drawn as part of a bitmap item.
 *      This procedure is where the child bitmap's placement is
 *      computed.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The fields x1, y1, x2, and y2 are updated in the header
 *      for itemPtr.
 *
 *--------------------------------------------------------------
 */

        /* ARGSUSED */
static void
ComputeBitmapBbox(canvas, bmapPtr)
    Tk_Canvas canvas;                   /* Canvas that contains item. */
    BitmapItem *bmapPtr;                /* Item whose bbox is to be
                                         * recomputed. */
{
    int width, height;
    int x, y;
    Pixmap bitmap;
    Tk_State state = bmapPtr->header.state;

    if(state == TK_STATE_NULL) {
        state = ((TkCanvas *)canvas)->canvas_state;
    }
    bitmap = bmapPtr->bitmap;
    if (((TkCanvas *)canvas)->currentItemPtr == (Tk_Item *)bmapPtr) {
        if (bmapPtr->activeBitmap!=None) {
            bitmap = bmapPtr->activeBitmap;
        }
    } else if (state==TK_STATE_DISABLED) {
        if (bmapPtr->disabledBitmap!=None) {
            bitmap = bmapPtr->disabledBitmap;
        }
    }

    x = (int) (bmapPtr->x + ((bmapPtr->x >= 0) ? 0.5 : - 0.5));
    y = (int) (bmapPtr->y + ((bmapPtr->y >= 0) ? 0.5 : - 0.5));

    if (state==TK_STATE_HIDDEN || bitmap == None) {
        bmapPtr->header.x1 = bmapPtr->header.x2 = x;
        bmapPtr->header.y1 = bmapPtr->header.y2 = y;
        return;
    }

    /*
     * Compute location and size of bitmap, using anchor information.
     */

    Tk_SizeOfBitmap(Tk_Display(Tk_CanvasTkwin(canvas)), bmapPtr->bitmap,
            &width, &height);
    switch (bmapPtr->anchor) {
        case TK_ANCHOR_N:
            x -= width/2;
            break;
        case TK_ANCHOR_NE:
            x -= width;
            break;
        case TK_ANCHOR_E:
            x -= width;
            y -= height/2;
            break;
        case TK_ANCHOR_SE:
            x -= width;
            y -= height;
            break;
        case TK_ANCHOR_S:
            x -= width/2;
            y -= height;
            break;
        case TK_ANCHOR_SW:
            y -= height;
            break;
        case TK_ANCHOR_W:
            y -= height/2;
            break;
        case TK_ANCHOR_NW:
            break;
        case TK_ANCHOR_CENTER:
            x -= width/2;
            y -= height/2;
            break;
    }

    /*
     * Store the information in the item header.
     */

    bmapPtr->header.x1 = x;
    bmapPtr->header.y1 = y;
    bmapPtr->header.x2 = x + width;
    bmapPtr->header.y2 = y + height;
}

/*
 *--------------------------------------------------------------
 *
 * DisplayBitmap --
 *
 *      This procedure is invoked to draw a bitmap item in a given
 *      drawable.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      ItemPtr is drawn in drawable using the transformation
 *      information in canvas.
 *
 *--------------------------------------------------------------
 */

static void
DisplayBitmap(canvas, itemPtr, display, drawable, x, y, width, height)
    Tk_Canvas canvas;                   /* Canvas that contains item. */
    Tk_Item *itemPtr;                   /* Item to be displayed. */
    Display *display;                   /* Display on which to draw item. */
    Drawable drawable;                  /* Pixmap or window in which to draw
                                         * item. */
    int x, y, width, height;            /* Describes region of canvas that
                                         * must be redisplayed (not used). */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
    int bmapX, bmapY, bmapWidth, bmapHeight;
    short drawableX, drawableY;
    XColor *fgColor;
    XColor *bgColor;
    Pixmap bitmap;
    Tk_State state = itemPtr->state;

    /*
     * If the area being displayed doesn't cover the whole bitmap,
     * then only redisplay the part of the bitmap that needs
     * redisplay.
     */

    if(state == TK_STATE_NULL) {
        state = ((TkCanvas *)canvas)->canvas_state;
    }
    fgColor = bmapPtr->fgColor;
    bgColor = bmapPtr->bgColor;
    bitmap = bmapPtr->bitmap;
    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
        if (bmapPtr->activeFgColor!=NULL) {
            fgColor = bmapPtr->activeFgColor;
        }
        if (bmapPtr->activeBgColor!=NULL) {
            bgColor = bmapPtr->activeBgColor;
        }
        if (bmapPtr->activeBitmap!=None) {
            bitmap = bmapPtr->activeBitmap;
        }
    } else if (state==TK_STATE_DISABLED) {
        if (bmapPtr->disabledFgColor!=NULL) {
            fgColor = bmapPtr->disabledFgColor;
        }
        if (bmapPtr->disabledBgColor!=NULL) {
            bgColor = bmapPtr->disabledBgColor;
        }
        if (bmapPtr->disabledBitmap!=None) {
            bitmap = bmapPtr->disabledBitmap;
        }
    }

    if (bitmap != None) {
        if (x > bmapPtr->header.x1) {
            bmapX = x - bmapPtr->header.x1;
            bmapWidth = bmapPtr->header.x2 - x;
        } else {
            bmapX = 0;
            if ((x+width) < bmapPtr->header.x2) {
                bmapWidth = x + width - bmapPtr->header.x1;
            } else {
                bmapWidth = bmapPtr->header.x2 - bmapPtr->header.x1;
            }
        }
        if (y > bmapPtr->header.y1) {
            bmapY = y - bmapPtr->header.y1;
            bmapHeight = bmapPtr->header.y2 - y;
        } else {
            bmapY = 0;
            if ((y+height) < bmapPtr->header.y2) {
                bmapHeight = y + height - bmapPtr->header.y1;
            } else {
                bmapHeight = bmapPtr->header.y2 - bmapPtr->header.y1;
            }
        }
        Tk_CanvasDrawableCoords(canvas,
                (double) (bmapPtr->header.x1 + bmapX),
                (double) (bmapPtr->header.y1 + bmapY),
                &drawableX, &drawableY);

        /*
         * Must modify the mask origin within the graphics context
         * to line up with the bitmap's origin (in order to make
         * bitmaps with "-background {}" work right).
         */
 
        XSetClipOrigin(display, bmapPtr->gc, drawableX - bmapX,
                drawableY - bmapY);
        XCopyPlane(display, bitmap, drawable,
                bmapPtr->gc, bmapX, bmapY, (unsigned int) bmapWidth,
                (unsigned int) bmapHeight, drawableX, drawableY, 1);
        XSetClipOrigin(display, bmapPtr->gc, 0, 0);
    }
}

/*
 *--------------------------------------------------------------
 *
 * BitmapToPoint --
 *
 *      Computes the distance from a given point to a given
 *      rectangle, in canvas units.
 *
 * Results:
 *      The return value is 0 if the point whose x and y coordinates
 *      are coordPtr[0] and coordPtr[1] is inside the bitmap.  If the
 *      point isn't inside the bitmap then the return value is the
 *      distance from the point to the bitmap.
 *
 * Side effects:
 *      None.
 *
 *--------------------------------------------------------------
 */

        /* ARGSUSED */
static double
BitmapToPoint(canvas, itemPtr, coordPtr)
    Tk_Canvas canvas;           /* Canvas containing item. */
    Tk_Item *itemPtr;           /* Item to check against point. */
    double *coordPtr;           /* Pointer to x and y coordinates. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
    double x1, x2, y1, y2, xDiff, yDiff;

    x1 = bmapPtr->header.x1;
    y1 = bmapPtr->header.y1;
    x2 = bmapPtr->header.x2;
    y2 = bmapPtr->header.y2;

    /*
     * Point is outside rectangle.
     */

    if (coordPtr[0] < x1) {
        xDiff = x1 - coordPtr[0];
    } else if (coordPtr[0] > x2)  {
        xDiff = coordPtr[0] - x2;
    } else {
        xDiff = 0;
    }

    if (coordPtr[1] < y1) {
        yDiff = y1 - coordPtr[1];
    } else if (coordPtr[1] > y2)  {
        yDiff = coordPtr[1] - y2;
    } else {
        yDiff = 0;
    }

    return hypot(xDiff, yDiff);
}

/*
 *--------------------------------------------------------------
 *
 * BitmapToArea --
 *
 *      This procedure is called to determine whether an item
 *      lies entirely inside, entirely outside, or overlapping
 *      a given rectangle.
 *
 * Results:
 *      -1 is returned if the item is entirely outside the area
 *      given by rectPtr, 0 if it overlaps, and 1 if it is entirely
 *      inside the given area.
 *
 * Side effects:
 *      None.
 *
 *--------------------------------------------------------------
 */

        /* ARGSUSED */
static int
BitmapToArea(canvas, itemPtr, rectPtr)
    Tk_Canvas canvas;           /* Canvas containing item. */
    Tk_Item *itemPtr;           /* Item to check against rectangle. */
    double *rectPtr;            /* Pointer to array of four coordinates
                                 * (x1, y1, x2, y2) describing rectangular
                                 * area.  */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;

    if ((rectPtr[2] <= bmapPtr->header.x1)
            || (rectPtr[0] >= bmapPtr->header.x2)
            || (rectPtr[3] <= bmapPtr->header.y1)
            || (rectPtr[1] >= bmapPtr->header.y2)) {
        return -1;
    }
    if ((rectPtr[0] <= bmapPtr->header.x1)
            && (rectPtr[1] <= bmapPtr->header.y1)
            && (rectPtr[2] >= bmapPtr->header.x2)
            && (rectPtr[3] >= bmapPtr->header.y2)) {
        return 1;
    }
    return 0;
}

/*
 *--------------------------------------------------------------
 *
 * ScaleBitmap --
 *
 *      This procedure is invoked to rescale a bitmap item in a
 *      canvas.  It is one of the standard item procedures for
 *      bitmap items, and is invoked by the generic canvas code.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The item referred to by itemPtr is rescaled so that the
 *      following transformation is applied to all point coordinates:
 *              x' = originX + scaleX*(x-originX)
 *              y' = originY + scaleY*(y-originY)
 *
 *--------------------------------------------------------------
 */

static void
ScaleBitmap(canvas, itemPtr, originX, originY, scaleX, scaleY)
    Tk_Canvas canvas;                   /* Canvas containing rectangle. */
    Tk_Item *itemPtr;                   /* Rectangle to be scaled. */
    double originX, originY;            /* Origin about which to scale item. */
    double scaleX;                      /* Amount to scale in X direction. */
    double scaleY;                      /* Amount to scale in Y direction. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;

    bmapPtr->x = originX + scaleX*(bmapPtr->x - originX);
    bmapPtr->y = originY + scaleY*(bmapPtr->y - originY);
    ComputeBitmapBbox(canvas, bmapPtr);
}

/*
 *--------------------------------------------------------------
 *
 * TranslateBitmap --
 *
 *      This procedure is called to move an item by a given amount.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The position of the item is offset by (xDelta, yDelta), and
 *      the bounding box is updated in the generic part of the item
 *      structure.
 *
 *--------------------------------------------------------------
 */

static void
TranslateBitmap(canvas, itemPtr, deltaX, deltaY)
    Tk_Canvas canvas;                   /* Canvas containing item. */
    Tk_Item *itemPtr;                   /* Item that is being moved. */
    double deltaX, deltaY;              /* Amount by which item is to be
                                         * moved. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;

    bmapPtr->x += deltaX;
    bmapPtr->y += deltaY;
    ComputeBitmapBbox(canvas, bmapPtr);
}

/*
 *--------------------------------------------------------------
 *
 * BitmapToPostscript --
 *
 *      This procedure is called to generate Postscript for
 *      bitmap items.
 *
 * Results:
 *      The return value is a standard Tcl result.  If an error
 *      occurs in generating Postscript then an error message is
 *      left in the interp's result, replacing whatever used to be there.
 *      If no error occurs, then Postscript for the item is appended
 *      to the result.
 *
 * Side effects:
 *      None.
 *
 *--------------------------------------------------------------
 */

static int
BitmapToPostscript(interp, canvas, itemPtr, prepass)
    Tcl_Interp *interp;                 /* Leave Postscript or error message
                                         * here. */
    Tk_Canvas canvas;                   /* Information about overall canvas. */
    Tk_Item *itemPtr;                   /* Item for which Postscript is
                                         * wanted. */
    int prepass;                        /* 1 means this is a prepass to
                                         * collect font information;  0 means
                                         * final Postscript is being created. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
    double x, y;
    int width, height, rowsAtOnce, rowsThisTime;
    int curRow;
    char buffer[100 + TCL_DOUBLE_SPACE * 2 + TCL_INTEGER_SPACE * 4];

    if (bmapPtr->bitmap == None) {
        return TCL_OK;
    }

    /*
     * Compute the coordinates of the lower-left corner of the bitmap,
     * taking into account the anchor position for the bitmp.
     */

    x = bmapPtr->x;
    y = Tk_CanvasPsY(canvas, bmapPtr->y);
    Tk_SizeOfBitmap(Tk_Display(Tk_CanvasTkwin(canvas)), bmapPtr->bitmap,
            &width, &height);
    switch (bmapPtr->anchor) {
        case TK_ANCHOR_NW:                      y -= height;            break;
        case TK_ANCHOR_N:       x -= width/2.0; y -= height;            break;
        case TK_ANCHOR_NE:      x -= width;     y -= height;            break;
        case TK_ANCHOR_E:       x -= width;     y -= height/2.0;        break;
        case TK_ANCHOR_SE:      x -= width;                             break;
        case TK_ANCHOR_S:       x -= width/2.0;                         break;
        case TK_ANCHOR_SW:                                              break;
        case TK_ANCHOR_W:                       y -= height/2.0;        break;
        case TK_ANCHOR_CENTER:  x -= width/2.0; y -= height/2.0;        break;
    }

    /*
     * Color the background, if there is one.
     */

    if (bmapPtr->bgColor != NULL) {
        sprintf(buffer,
                "%.15g %.15g moveto %d 0 rlineto 0 %d rlineto %d %s\n",
                x, y, width, height, -width, "0 rlineto closepath");
        Tcl_AppendResult(interp, buffer, (char *) NULL);
        if (Tk_CanvasPsColor(interp, canvas, bmapPtr->bgColor) != TCL_OK) {
            return TCL_ERROR;
        }
        Tcl_AppendResult(interp, "fill\n", (char *) NULL);
    }

    /*
     * Draw the bitmap, if there is a foreground color.  If the bitmap
     * is very large, then chop it up into multiple bitmaps, each
     * consisting of one or more rows.  This is needed because Postscript
     * can't handle single strings longer than 64 KBytes long.
     */

    if (bmapPtr->fgColor != NULL) {
        if (Tk_CanvasPsColor(interp, canvas, bmapPtr->fgColor) != TCL_OK) {
            return TCL_ERROR;
        }
        if (width > 60000) {
            Tcl_ResetResult(interp);
            Tcl_AppendResult(interp, "can't generate Postscript",
                    " for bitmaps more than 60000 pixels wide",
                    (char *) NULL);
            return TCL_ERROR;
        }
        rowsAtOnce = 60000/width;
        if (rowsAtOnce < 1) {
            rowsAtOnce = 1;
        }
        sprintf(buffer, "%.15g %.15g translate\n", x, y+height);
        Tcl_AppendResult(interp, buffer, (char *) NULL);
        for (curRow = 0; curRow < height; curRow += rowsAtOnce) {
            rowsThisTime = rowsAtOnce;
            if (rowsThisTime > (height - curRow)) {
                rowsThisTime = height - curRow;
            }
            sprintf(buffer, "0 -%.15g translate\n%d %d true matrix {\n",
                    (double) rowsThisTime, width, rowsThisTime);
            Tcl_AppendResult(interp, buffer, (char *) NULL);
            if (Tk_CanvasPsBitmap(interp, canvas, bmapPtr->bitmap,
                    0, curRow, width, rowsThisTime) != TCL_OK) {
                return TCL_ERROR;
            }
            Tcl_AppendResult(interp, "\n} imagemask\n", (char *) NULL);
        }
    }
    return TCL_OK;
}

/* End of tkcanvbmap.c */