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IABSD.fr/xenocara/app/bitmap/Graphics.c

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  • Author : matthieu
    Date : 2006-11-25 20:07:29
    Hash : 616b6f15
    Message : Importing from X.Org 7.2RC2

  • app/bitmap/Graphics.c
  • /* $Xorg: Graphics.c,v 1.4 2001/02/09 02:05:28 xorgcvs Exp $ */
    /*
    
    Copyright 1989, 1998  The Open Group
    
    Permission to use, copy, modify, distribute, and sell this software and its
    documentation for any purpose is hereby granted without fee, provided that
    the above copyright notice appear in all copies and that both that
    copyright notice and this permission notice appear in supporting
    documentation.
    
    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.
    
    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
    OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
    ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
    OTHER DEALINGS IN THE SOFTWARE.
    
    Except as contained in this notice, the name of The Open Group shall
    not be used in advertising or otherwise to promote the sale, use or
    other dealings in this Software without prior written authorization
    from The Open Group.
    
    */
    /* $XFree86: xc/programs/bitmap/Graphics.c,v 1.5 2001/01/17 23:44:51 dawes Exp $ */
    
    /*
     * Author:  Davor Matic, MIT X Consortium
     */
    
    #include <X11/IntrinsicP.h>
    #include <X11/StringDefs.h>
    #include <X11/Xfuncs.h>
    #include "BitmapP.h"
    #include "Bitmap.h"
    #include "Requests.h"
        
    #include <stdio.h>
    #include <math.h>
    
    #ifndef abs
    #define abs(x)                        (((x) > 0) ? (x) : -(x))
    #endif
    #define min(x, y)                     (((int)(x) < (int)(y)) ? (x) : (y))
    #define max(x, y)                     (((int)(x) > (int)(y)) ? (x) : (y))
    #ifndef rint
    #define rint(x)                       floor(x + 0.5)
    #endif
    
    /*****************************************************************************\
     *                                   Graphics                                *
    \*****************************************************************************/
    
    #define GetBit(image, x, y)\
        ((bit)((*(image->data + (x) / 8 + (y) * image->bytes_per_line) &\
    	    (1 << ((x) % 8))) ? 1 : 0))
    
    #if 0
    bit 
    BWGetBit(Widget w, Position x, Position y)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        if (QueryInBitmap(BW, x, y))
    	return GetBit(BW->bitmap.image, x, y);
        else
    	return NotSet;
    }
    #endif
    
    #define InvertBit(image, x, y)\
        (*(image->data + (x) / 8 + (y) * image->bytes_per_line) ^=\
         (bit) (1 << ((x) % 8)))
    
    
    #define SetBit(image, x, y)\
        (*(image->data + (x) / 8 + (y) * image->bytes_per_line) |=\
         (bit) (1 << ((x) % 8)))
    
    #define ClearBit(image, x, y)\
        (*(image->data + (x) / 8 + (y) * image->bytes_per_line) &=\
         (bit)~(1 << ((x) % 8)))
    
    
    #define HighlightSquare(BW, x, y)\
        XFillRectangle(XtDisplay(BW), XtWindow(BW),\
                       BW->bitmap.highlighting_gc,\
    		   InWindowX(BW, x), InWindowY(BW, y),\
                       BW->bitmap.squareW, BW->bitmap.squareH)
    /*
    void 
    HighlightSquare(BitmapWidget BW, Position x, Position y)
    {
        XFillRectangle(XtDisplay(BW), XtWindow(BW),
                       BW->bitmap.highlighting_gc,
    		   InWindowX(BW, x), InWindowY(BW, y),
                       BW->bitmap.squareW, BW->bitmap.squareH);
    }
    */
    
    #define DrawSquare(BW, x, y)\
        XFillRectangle(XtDisplay(BW), XtWindow(BW),\
                       BW->bitmap.drawing_gc,\
    		   InWindowX(BW, x), InWindowY(BW, y),\
                       BW->bitmap.squareW, BW->bitmap.squareH) 
    
    /*
    void 
    DrawSquare(BitmapWidget BW, Position x, Position y)
    {
        XFillRectangle(XtDisplay(BW), XtWindow(BW),
                       BW->bitmap.drawing_gc,
    		   InWindowX(BW, x), InWindowY(BW, y),
                       BW->bitmap.squareW, BW->bitmap.squareH);
    }
    */
    
    #define InvertPoint(BW, x, y)\
        {InvertBit(BW->bitmap.image, x, y); DrawSquare(BW, x, y);}
    
    #define DrawPoint(BW, x, y, value)\
        if (GetBit(BW->bitmap.image, x, y) != value)\
           InvertPoint(BW, x, y)
    
    void 
    BWDrawPoint(Widget w, Position x, Position y, bit value)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        if (QueryInBitmap(BW, x, y)) {
    	if (value == Highlight)
    	    HighlightSquare(BW, x, y);
    	else
    	    DrawPoint(BW, x, y, value);
        }
    }
    
    static XPoint *
    HotSpotShape(BitmapWidget BW, Position x, Position y)
    {
        static XPoint points[5];
      
        points[0].x = InWindowX(BW, x);
        points[0].y = InWindowY(BW, y + 1.0/2);
        points[1].x = InWindowX(BW, x + 1.0/2);
        points[1].y = InWindowY(BW, y + 1);
        points[2].x = InWindowX(BW, x + 1);
        points[2].y = InWindowY(BW, y + 1.0/2);
        points[3].x = InWindowX(BW, x + 1.0/2);
        points[3].y = InWindowY(BW, y);
        points[4].x = InWindowX(BW, x);
        points[4].y = InWindowY(BW, y + 1.0/2);
        
        return points;
    }
    
    #define DrawHotSpot(BW, x, y)\
      XFillPolygon(XtDisplay(BW), XtWindow(BW), BW->bitmap.drawing_gc,\
    	       HotSpotShape(BW, x, y), 5, Convex, CoordModeOrigin)
    
    #define HighlightHotSpot(BW, x, y)\
      XFillPolygon(XtDisplay(BW), XtWindow(BW), BW->bitmap.highlighting_gc,\
    	       HotSpotShape(BW, x, y), 5, Convex, CoordModeOrigin)
    
    /*
    XImage *CreateBitmapImage();
    void DestroyBitmapImage();
    */
    
    void 
    BWRedrawHotSpot(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
    
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y))
    	DrawHotSpot(BW, BW->bitmap.hot.x, BW->bitmap.hot.y);
    }
    
    void 
    BWClearHotSpot(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)) {
          DrawHotSpot(BW, BW->bitmap.hot.x, BW->bitmap.hot.y);
          BW->bitmap.hot.x = BW->bitmap.hot.y = NotSet;
        }
    }
    
    void 
    BWDrawHotSpot(Widget w, Position x, Position y, int value)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        if (QueryInBitmap(BW, x, y)) {
    	if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y) &&
    	    ((BW->bitmap.hot.x == x) && (BW->bitmap.hot.y == y))) {
    	    if ((value == Clear) || (value == Invert)) {
    		BWClearHotSpot(w);
    	    }
    	}
    	else
    	    if ((value == Set) || (value == Invert)) {
    		BWClearHotSpot(w);
    		DrawHotSpot(BW, x, y);
    		BW->bitmap.hot.x = x;
    		BW->bitmap.hot.y = y;
    	    }
    	
    	if (value == Highlight)
    	    HighlightHotSpot(BW, x, y); 
        }
    }
    
    void 
    BWSetHotSpot(Widget w, Position x, Position y)
    {
        if (QuerySet(x, y))
    	BWDrawHotSpot(w, x, y, Set);
        else
    	BWClearHotSpot(w);
    }
    
    /* high level procedures */
    
    void 
    BWRedrawSquares(Widget w, 
    		Position x, Position y, 
    		Dimension width, Dimension height)
    {
        BitmapWidget BW = (BitmapWidget) w;
        Position from_x = InBitmapX(BW, x);
        Position from_y = InBitmapY(BW, y);
        Position to_x = InBitmapX(BW, x + width);
        Position to_y = InBitmapY(BW, y + height);
    
        QuerySwap(from_x, to_x);
        QuerySwap(from_y, to_y);
        from_x = max(0, from_x);
        from_y = max(0, from_y);
        to_x = min(BW->bitmap.image->width - 1, to_x);
        to_y = min(BW->bitmap.image->height - 1, to_y);
      
        for (x = from_x; x <= to_x; x++)
    	for (y = from_y; y <= to_y; y++)
    	    if (GetBit(BW->bitmap.image, x, y)) DrawSquare(BW, x, y);
    }
    
    void 
    BWDrawGrid(Widget w, 
    	   Position from_x, Position from_y, 
    	   Position to_x, Position to_y)
    {
        BitmapWidget BW = (BitmapWidget) w;
        int i;
      
        QuerySwap(from_x, to_x);
        QuerySwap(from_y, to_y);
        from_x = max(0, from_x);
        from_y = max(0, from_y);
        to_x = min(BW->bitmap.image->width - 1, to_x);
        to_y = min(BW->bitmap.image->height - 1, to_y);
      
        for(i = from_x + (from_x == 0); i <= to_x; i++)
    	XDrawLine(XtDisplay(BW), XtWindow(BW), 
    		  BW->bitmap.frame_gc,
    		  InWindowX(BW, i), InWindowY(BW, from_y),
    		  InWindowX(BW, i), InWindowY(BW, to_y + 1));
      
        for(i = from_y + (from_y == 0); i <= to_y; i++)
    	XDrawLine(XtDisplay(BW), XtWindow(BW), 
    		  BW->bitmap.frame_gc,
    		  InWindowX(BW, from_x), InWindowY(BW, i),
    		  InWindowX(BW, to_x + 1), InWindowY(BW, i));
    }
    
    
    void 
    BWRedrawGrid(Widget w, 
    	     Position x, Position y, 
    	     Dimension width, Dimension height)
    {
        BitmapWidget BW = (BitmapWidget) w;
        Position from_x = InBitmapX(BW, x);
        Position from_y = InBitmapY(BW, y);
        Position to_x = InBitmapX(BW, x + width);
        Position to_y = InBitmapY(BW, y + height);
    
        if (BW->bitmap.grid)
    	BWDrawGrid(w, from_x, from_y, to_x, to_y);
    }
    
    void 
    BWDrawLine(Widget w, 
    	   Position from_x, Position from_y, 
    	   Position to_x, Position to_y, int value)
    {
        Position i;
        register double x, y;
        double dx, dy, delta;
    
        dx = to_x - from_x;
        dy = to_y - from_y;
        x = from_x + 0.5;
        y = from_y + 0.5;
        delta = max(abs(dx), abs(dy));
        if (delta > 0) {
    	dx /= delta;
    	dy /= delta;
    	for(i = 0; i <= delta; i++) {
    	    BWDrawPoint(w, (Position) x, (Position) y, value);
    	    x += dx;
    	    y += dy;
    	}
        }
        else
    	BWDrawPoint(w, from_x, from_y, value);
    }
    
    void 
    BWBlindLine(Widget w, 
    	    Position from_x, Position from_y, 
    	    Position to_x, Position to_y, int value)
    {
        Position i;
        register double x, y;
        double dx, dy, delta;
    
        dx = to_x - from_x;
        dy = to_y - from_y;
        x = from_x + 0.5;
        y = from_y + 0.5;
        delta = max(abs(dx), abs(dy));
        if (delta > 0) {
    	dx /= delta;
    	dy /= delta;
    	x += dx;
    	y += dy;
    	for(i = 1; i <= delta; i++) {
    	    BWDrawPoint(w, (Position) x, (Position) y, value);
    	    x += dx;
    	    y += dy;
    	}
        }
        else
    	BWDrawPoint(w, from_x, from_y, value);
    }
    
    void 
    BWDrawRectangle(Widget w, 
    		Position from_x, Position from_y, 
    		Position to_x, Position to_y, int value)
    {
        register Position i;
        Dimension delta, width, height;
        
        QuerySwap(from_x, to_x);
        QuerySwap(from_y, to_y);
        
        width = to_x - from_x;
        height = to_y - from_y;
    
        delta = max(width, height);
        
        if (!QueryZero(width, height)) {
    	for (i = 0; (int)i < (int)delta; i++) {
    	    if ((int)i < (int)width) {
    		BWDrawPoint(w, from_x + i, from_y, value);
    		BWDrawPoint(w, to_x - i, to_y, value);
    	    }
    	    if ((int)i < (int)height) {
    		BWDrawPoint(w, from_x, to_y - i, value);
    		BWDrawPoint(w, to_x, from_y + i, value);
    	    }
    	}
        }
        else
    	BWDrawLine(w, 
    		   from_x, from_y, 
    		   to_x, to_y, value);
    }
      
    void 
    BWDrawFilledRectangle(Widget w, 
    		      Position from_x, Position from_y, 
    		      Position to_x, Position to_y, int value)
    {
        register Position x, y;
    
        QuerySwap(from_x, to_x);
        QuerySwap(from_y, to_y);
        
        for (x = from_x; x <= to_x; x++)
    	for (y = from_y; y <= to_y; y++)
    	    BWDrawPoint(w, x, y, value);
    }
    
    void 
    BWDrawCircle(Widget w, 
    	     Position origin_x, Position origin_y, 
    	     Position point_x, Position point_y, int value)
    {
        register Position i, delta;
        Dimension dx, dy, half;
        double radius;
        
        dx = abs(point_x - origin_x);
        dy = abs(point_y - origin_y);
        radius = sqrt((double) ((int)dx * (int)dx + (int)dy * (int)dy));
        if (radius < 1.0) {
    	BWDrawPoint(w, origin_x, origin_y, value);
        }
        else {
    	BWDrawPoint(w, origin_x - (Position) floor(radius), origin_y, value);
    	BWDrawPoint(w, origin_x + (Position) floor(radius), origin_y, value);
    	BWDrawPoint(w, origin_x, origin_y - (Position) floor(radius), value);
    	BWDrawPoint(w, origin_x, origin_y + (Position) floor(radius), value);
        }
        half = radius / sqrt(2.0);
        for(i = 1; (int)i <= (int)half; i++) {
    	delta = sqrt(radius * radius - i * i);
    	BWDrawPoint(w, origin_x - delta, origin_y - i, value);
    	BWDrawPoint(w, origin_x - delta, origin_y + i, value);
    	BWDrawPoint(w, origin_x + delta, origin_y - i, value);
    	BWDrawPoint(w, origin_x + delta, origin_y + i, value);
    	if (i != delta) {
    	    BWDrawPoint(w, origin_x - i, origin_y - delta, value);
    	    BWDrawPoint(w, origin_x - i, origin_y + delta, value);
    	    BWDrawPoint(w, origin_x + i, origin_y - delta, value);
    	    BWDrawPoint(w, origin_x + i, origin_y + delta, value);
    	}
        }
    }
    
    void 
    BWDrawFilledCircle(Widget w, 
    		   Position origin_x, Position origin_y, 
    		   Position point_x, Position point_y, int value)
    {
        register Position i, j, delta;
        Dimension dx, dy;
        double radius;
        
        dx = abs(point_x - origin_x);
        dy = abs(point_y - origin_y);
        radius = sqrt((double) ((int)dx * (int)dx + (int)dy * (int)dy));
        for(j = origin_x - (Position) floor(radius); 
    	j <= origin_x + (Position) floor(radius); j++)
    	BWDrawPoint(w, j, origin_y, value);
        for(i = 1; i <= (Position) floor(radius); i++) {
    	delta = sqrt(radius * radius - i * i);
    	for(j = origin_x - delta; j <= origin_x + delta; j++) {
    	    BWDrawPoint(w, j, origin_y - i, value);
    	    BWDrawPoint(w, j, origin_y + i, value);
    	}
        }
    }
    
    #define QueryFlood(BW, x, y, value)\
        ((GetBit(BW->bitmap.image, x, y) !=\
          (value & 1)) && QueryInBitmap(BW, x, y))
    
    #define Flood(BW, x, y, value)\
        {if (value == Highlight) HighlightSquare(BW, x, y);\
         else InvertPoint(BW, x, y);}
    
    /*
    static void 
    FloodLoop(BitmapWidget BW, Position x, Position y, int value)
    {
        if (QueryFlood(BW, x, y, value)) {
    	Flood(BW, x, y, value);
    	FloodLoop(BW, x, y - 1, value);
    	FloodLoop(BW, x - 1, y, value);
    	FloodLoop(BW, x, y + 1, value);
    	FloodLoop(BW, x + 1, y, value);
        }
    }
    */
    
    static void 
    FloodLoop(BitmapWidget BW, Position x, Position y, int value)
    {
        Position save_x, save_y, x_left, x_right;
        
        if (QueryFlood(BW, x, y, value)) 
    	Flood(BW, x, y, value)
    
    
        save_x = x;
        save_y = y;
    
        x++;
        while (QueryFlood(BW, x, y, value)) {
    	Flood(BW, x, y, value);
    	x++;
        }
        x_right = --x;
    
        x = save_x;
        x--;
        while (QueryFlood(BW, x, y, value)) {
    	Flood(BW, x, y, value);
    	x--;
        }
        x_left = ++x;
    
    
        x = x_left;
        y = save_y;
        y++;
        
        while (x <= x_right) {
    	Boolean flag = False;
    	Position x_enter;
    	
    	while (QueryFlood(BW, x, y, value) && (x <= x_right)) {
    	    flag = True;
    	    x++;
    	}
    	
    	if (flag) {
    	    if ((x == x_right) && QueryFlood(BW, x, y, value))
    		FloodLoop(BW, x, y, value);
    	    else
    		FloodLoop(BW, x - 1, y, value);
    	}
    	
    	x_enter = x;
    	
    	while (!QueryFlood(BW, x, y, value) && (x < x_right))
    	    x++;
    	
    	if (x == x_enter) x++;
        }
    
        x = x_left;
        y = save_y;
        y--;
    
        while (x <= x_right) {
    	Boolean flag = False;
    	Position x_enter;
    	
    	while (QueryFlood(BW, x, y, value) && (x <= x_right)) {
    	    flag = True;
    	    x++;
    	}
    	
    	if (flag) {
    	    if ((x == x_right) && QueryFlood(BW, x, y, value))
    		FloodLoop(BW, x, y, value);
    	    else
    		FloodLoop(BW, x - 1, y, value);
    	}
    	
    	x_enter = x;
    	
    	while (!QueryFlood(BW, x, y, value) && (x < x_right))
    	    x++;
    	
    	if (x == x_enter) x++;
        }
    }
    
    void 
    BWFloodFill(Widget w, Position x, Position y, int value)
    {
        BitmapWidget BW = (BitmapWidget) w;
        int pixel;
    
        pixel = GetBit(BW->bitmap.image, x, y);
    
        if (value == Invert)
    	FloodLoop(BW, x, y, (pixel ? Clear : Set));
        else if (value != pixel)
    	FloodLoop(BW, x, y, value); 
    }
    
    #define QueryHotInMark(BW)\
        ((BW->bitmap.hot.x == max(BW->bitmap.mark.from_x,\
    			      min(BW->bitmap.hot.x, BW->bitmap.mark.to_x)))\
         &&\
         (BW->bitmap.hot.y == max(BW->bitmap.mark.from_y,\
    			      min(BW->bitmap.hot.y, BW->bitmap.mark.to_y))))
    
    void 
    BWUp(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        register Position x, y;
        bit first, up, down=0;
        Position from_x, from_y, to_x, to_y;
    
        if (BWQueryMarked(w)) {
    	from_x = BW->bitmap.mark.from_x;
    	from_y = BW->bitmap.mark.from_y;
    	to_x = BW->bitmap.mark.to_x;
    	to_y = BW->bitmap.mark.to_y;
        }
        else {
    	from_x = 0;
    	from_y = 0;
    	to_x = BW->bitmap.width - 1;
    	to_y = BW->bitmap.height - 1;
        }
    
        if ((to_y - from_y) == 0)
    	return;
        
        for(x = from_x; x <= to_x; x++) {
    	first = up = GetBit(BW->bitmap.image, x, to_y);
    	for(y = to_y - 1; y >= from_y; y--) {
    	    down = GetBit(BW->bitmap.image, x, y);
    	    if (up != down) 
    		InvertPoint(BW, x, y);
    	    up =down;
    	}
    	if(first != down)
    	    InvertPoint(BW, x, to_y);
        }
    
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)
    	&&
    	!BWQueryMarked(w))
    	BWSetHotSpot(w,
    		     BW->bitmap.hot.x,
    		     (BW->bitmap.hot.y - 1 + BW->bitmap.image->height) % 
    		     BW->bitmap.image->height);
    
    }
    
    void 
    BWDown(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        register Position x, y;
        bit first, down, up=0;
        Position from_x, from_y, to_x, to_y;
    
        if (BWQueryMarked(w)) {
    	from_x = BW->bitmap.mark.from_x;
    	from_y = BW->bitmap.mark.from_y;
    	to_x = BW->bitmap.mark.to_x;
    	to_y = BW->bitmap.mark.to_y;
        }
        else {
    	from_x = 0;
    	from_y = 0;
    	to_x = BW->bitmap.width - 1;
    	to_y = BW->bitmap.height - 1;
        }
    
        if ((to_y - from_y) == 0)
    	return;
    
        for(x = from_x; x <= to_x; x++) {
    	first = down = GetBit(BW->bitmap.image, x, from_y);
    	for(y = from_y + 1; y <= to_y; y++) {
    	    up = GetBit(BW->bitmap.image, x, y);
    	    if (down != up)
    		InvertPoint(BW, x, y);
    	    down = up;
    	}
    	if(first != up) 
    	    InvertPoint(BW, x, from_y);
        }
        
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)
    	&&
    	!BWQueryMarked(w))
    	BWSetHotSpot(w,
    		     BW->bitmap.hot.x,
    		     (BW->bitmap.hot.y + 1) % BW->bitmap.image->height);
    }
    
    void 
    BWLeft(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        register Position x, y;
        bit first, left, right=0;
        Position from_x, from_y, to_x, to_y;
        
        if (BWQueryMarked(w)) {
    	from_x = BW->bitmap.mark.from_x;
    	from_y = BW->bitmap.mark.from_y;
    	to_x = BW->bitmap.mark.to_x;
    	to_y = BW->bitmap.mark.to_y;
        }
        else {
    	from_x = 0;
    	from_y = 0;
    	to_x = BW->bitmap.width - 1;
    	to_y = BW->bitmap.height - 1;
        }
    
        if ((to_x - from_x) == 0)
    	return;
        
        for(y = from_y; y <= to_y; y++) {
    	first = left = GetBit(BW->bitmap.image, to_x, y);
    	for(x = to_x - 1; x >= from_x; x--) {
    	    right = GetBit(BW->bitmap.image, x, y);
    	    if (left != right)
    		InvertPoint(BW, x, y);
    	    left = right;
    	}
    	if(first != right)
    	    InvertPoint(BW, to_x, y);
        }
        
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)
    	&&
    	!BWQueryMarked(w))
    	BWSetHotSpot(w,
    		     (BW->bitmap.hot.x - 1 + BW->bitmap.image->width) % 
    		     BW->bitmap.image->width,
    		     BW->bitmap.hot.y);
    }
    
    void 
    BWRight(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        register Position x, y;
        bit first, right, left=0;
        Position from_x, from_y, to_x, to_y;
        
        if (BWQueryMarked(w)) {
    	from_x = BW->bitmap.mark.from_x;
    	from_y = BW->bitmap.mark.from_y;
    	to_x = BW->bitmap.mark.to_x;
    	to_y = BW->bitmap.mark.to_y;
        }
        else {
    	from_x = 0;
    	from_y = 0;
    	to_x = BW->bitmap.width - 1;
    	to_y = BW->bitmap.height - 1;
        }
        
        if ((to_x - from_x) == 0)
    	return;
        
        for(y = from_y; y <= to_y; y++) {
    	first = right = GetBit(BW->bitmap.image, from_x, y);
    	for(x = from_x + 1; x <= to_x; x++) {
    	    left = GetBit(BW->bitmap.image, x, y);
    	    if (right != left)
    		InvertPoint(BW, x, y);
    	    right = left;
    	}
    	if(first != left)
    	    InvertPoint(BW, from_x, y);
        }
    
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)
    	&&
    	!BWQueryMarked(w))
    	BWSetHotSpot(w,
    		     (BW->bitmap.hot.x + 1) % BW->bitmap.image->width,
    		     BW->bitmap.hot.y);
    }
    
    /* void TransferImageData(); */
    
    void 
    BWFold(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        Position x, y, new_x, new_y;
        Dimension horiz, vert;
        char *storage_data;
        XImage *storage;
    	
        storage_data = CreateCleanData(Length(BW->bitmap.image->width, 
    					  BW->bitmap.image->height));
    
        storage = CreateBitmapImage(BW, storage_data, 
    				(Dimension) BW->bitmap.image->width, 
    				(Dimension) BW->bitmap.image->height);
    
        TransferImageData(BW->bitmap.image, storage);
    
        BW->bitmap.fold ^= True;
        horiz = (BW->bitmap.image->width + BW->bitmap.fold) / 2;
        vert = (BW->bitmap.image->height + BW->bitmap.fold) / 2;
        
        for (x = 0; x < BW->bitmap.image->width; x++)
    	for (y = 0; y < BW->bitmap.image->height; y++) {
    	    new_x = (int)(x + horiz) % (int)BW->bitmap.image->width;
    	    new_y = (int)(y + vert) % (int)BW->bitmap.image->height;
    	    if(GetBit(BW->bitmap.image, new_x, new_y) != 
    	       GetBit(storage, x, y))
    		InvertPoint(BW, new_x, new_y);
    	}
        
        DestroyBitmapImage(&storage);
    
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y))
          BWSetHotSpot(w, 
    		   (Position) 
    		   ((int)(BW->bitmap.hot.x+horiz)
    		    %(int)BW->bitmap.image->width),
    		   (Position)
    		   ((int)(BW->bitmap.hot.y+vert)
    		    %(int)BW->bitmap.image->height)
    		   );
    }
    
    
    void 
    BWClear(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        register Position x, y;
        int i, length;
    
        length = Length(BW->bitmap.image->width, BW->bitmap.image->height);
    
        for (x = 0; x < BW->bitmap.image->width; x++)
    	for (y = 0; y < BW->bitmap.image->height; y++)
    	    if (GetBit(BW->bitmap.image, x, y))
    		DrawSquare(BW, x, y);
        
        for (i = 0; i < length; i++)
    	BW->bitmap.image->data[i] = 0;
    
    }
    
    void 
    BWSet(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        register Position x, y;
        int i, length;
        
        length = Length(BW->bitmap.image->width, BW->bitmap.image->height);
        
        for (x = 0; x < BW->bitmap.image->width; x++)
    	for (y = 0; y < BW->bitmap.image->height; y++)
    	    if (!GetBit(BW->bitmap.image, x, y))
    		DrawSquare(BW, x, y);
        
        for (i = 0; i < length; i++)
    	BW->bitmap.image->data[i] = (char)255;
    
    }
     
    void 
    BWRedraw(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
    
        XClearArea(XtDisplay(BW), XtWindow(BW),
    	       0, 0, BW->core.width, BW->core.height,
    	       True);
    }
    
    void 
    BWInvert(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        int i, length;
    
        length = Length(BW->bitmap.image->width, BW->bitmap.image->height);
    
        XFillRectangle(XtDisplay(BW), XtWindow(BW),
    		   BW->bitmap.drawing_gc,
    		   InWindowX(BW, 0), InWindowY(BW, 0),
    		   InWindowX(BW, BW->bitmap.image->width) - InWindowX(BW, 0),
    		   InWindowY(BW, BW->bitmap.image->height) - InWindowY(BW, 0));
        
        for (i = 0; i < length; i++)
    	BW->bitmap.image->data[i] ^= 255;
    }
    
    void 
    BWFlipHoriz(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        register Position x, y;
        Position from_x, from_y, to_x, to_y;
        float half;
        
        if (BWQueryMarked(w)) {
    	from_x = BW->bitmap.mark.from_x;
    	from_y = BW->bitmap.mark.from_y;
    	to_x = BW->bitmap.mark.to_x;
    	to_y = BW->bitmap.mark.to_y;
        }
        else {
    	from_x = 0;
    	from_y = 0;
    	to_x = BW->bitmap.width - 1;
    	to_y = BW->bitmap.height - 1;
        }
        half = (float) (to_y - from_y) / 2.0 + 0.5;
        
        if (half == 0.0)
    	return;
        
        for (x = from_x; x <= to_x; x++) 
    	for (y = 0; y <  half; y++)
    	    if (GetBit(BW->bitmap.image, x, from_y + y) != 
    		GetBit(BW->bitmap.image, x, to_y - y)) {
    		InvertPoint(BW, x, from_y + y);
    		InvertPoint(BW, x, to_y - y);
    	    }
        
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)
    	&&
    	!BWQueryMarked(w))
    	BWSetHotSpot(w,
    		     BW->bitmap.hot.x,
    		     BW->bitmap.image->height - 1 - BW->bitmap.hot.y);
    }
    
    void 
    BWFlipVert(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        register Position x, y;
        Position from_x, from_y, to_x, to_y;
        float half;
        
        if (BWQueryMarked(w)) {
    	from_x = BW->bitmap.mark.from_x;
    	from_y = BW->bitmap.mark.from_y;
    	to_x = BW->bitmap.mark.to_x;
    	to_y = BW->bitmap.mark.to_y;
        }
        else {
    	from_x = 0;
    	from_y = 0;
    	to_x = BW->bitmap.width - 1;
    	to_y = BW->bitmap.height - 1;
        }
        half = (float) (to_x - from_x) / 2.0 + 0.5;
    
        if (half == 0)
    	return;
    
        for (y = from_y; y <= to_y; y++)
    	for (x = 0; x < half; x++)
    	    if (GetBit(BW->bitmap.image, from_x + x, y) != 
    		GetBit(BW->bitmap.image, to_x - x, y)) {
    		InvertPoint(BW, from_x + x, y);
    		InvertPoint(BW, to_x - x, y);
    	    }
        
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)
    	&&
    	!BWQueryMarked(w))
    	BWSetHotSpot(w,
    		     BW->bitmap.image->width - 1 - BW->bitmap.hot.x,
    		     BW->bitmap.hot.y);
    }
    
    
    void 
    BWRotateRight(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        Position x, y, delta, shift, tmp;
        Position half_width, half_height;
        XPoint hot;
        bit quad1, quad2, quad3, quad4;
        Position from_x, from_y, to_x, to_y;
        
        if (BWQueryMarked(w)) {
    	from_x = BW->bitmap.mark.from_x;
    	from_y = BW->bitmap.mark.from_y;
    	to_x = BW->bitmap.mark.to_x;
    	to_y = BW->bitmap.mark.to_y;
        }
        else {
    	from_x = 0;
    	from_y = 0;
    	to_x = BW->bitmap.width - 1;
    	to_y = BW->bitmap.height - 1;
        }
    
        half_width = floor((to_x - from_x) / 2.0 + 0.5);
        half_height = floor((to_y - from_y ) / 2.0 + 0.5);
        shift = min((Position)(to_x - from_x), (Position)(to_y - from_y )) % 2;
        delta = min((Position) half_width, (Position) half_height) - shift;
        
        for (x = 0; x <= delta; x++) {
    	for (y = 1 - shift; y <= delta; y++) {
    	    quad1 = GetBit(BW->bitmap.image, 
    			   from_x + (Position)half_width + x, 
    			   from_y + (Position)half_height + y);
    	    quad2 = GetBit(BW->bitmap.image, 
    			   from_x + (Position)half_width + y, 
    			   from_y + (Position)half_height - shift - x);
    	    quad3 = GetBit(BW->bitmap.image, 
    			   from_x + (Position)half_width - shift - x, 
    			   from_y + (Position)half_height - shift - y);
    	    quad4 = GetBit(BW->bitmap.image, 
    			   from_x + (Position)half_width - shift - y, 
    			   from_y + (Position)half_height + x);
    
    	    if (quad1 != quad2)
    		InvertPoint(BW, 
    			    from_x + (Position)half_width + x, 
    			    from_y + (Position)half_height + y);
    	    if (quad2 != quad3)
    		InvertPoint(BW, 
    			    from_x + (Position)half_width + y, 
    			    from_y + (Position)half_height - shift - x);
    	    if (quad3 != quad4)
    		InvertPoint(BW, 
    			    from_x + (Position)half_width - shift - x,
    			    from_y + (Position)half_height - shift - y);
    	    if (quad4 != quad1)
    		InvertPoint(BW, 
    			    from_x + (Position)half_width - shift - y, 
    			    from_y + (Position)half_height + x);
    	}
        }
        
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)
    	&&
    	!BWQueryMarked(w)) {
    	hot.x = BW->bitmap.hot.x - half_width;
    	hot.y = BW->bitmap.hot.y - half_height;
    	if (hot.x >= 0) hot.x += shift;
    	if (hot.y >= 0) hot.y += shift;
    	tmp = hot.x;
    	hot.x = - hot.y;
    	hot.y = tmp;
    	if (hot.x > 0) hot.x -= shift;
    	if (hot.y > 0) hot.y -= shift;
    	hot.x += half_width;
    	hot.y += half_height;
    	if (QueryInBitmap(BW, hot.x, hot.y))
    	    BWSetHotSpot(w, hot.x, hot.y);
        }
        
    }
    
    void 
    BWRotateLeft(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        Position x, y,delta, shift, tmp;
        Position half_width, half_height;
        XPoint hot;
        bit quad1, quad2, quad3, quad4;
        Position from_x, from_y, to_x, to_y;
        
        if (BWQueryMarked(w)) {
    	from_x = BW->bitmap.mark.from_x;
    	from_y = BW->bitmap.mark.from_y;
    	to_x = BW->bitmap.mark.to_x;
    	to_y = BW->bitmap.mark.to_y;
        }
        else {
    	from_x = 0;
    	from_y = 0;
    	to_x = BW->bitmap.width - 1;
    	to_y = BW->bitmap.height - 1;
        }
    
        half_width = floor((to_x - from_x) / 2.0 + 0.5);
        half_height = floor((to_y - from_y ) / 2.0 + 0.5);
        shift = min((Position)(to_x - from_x), (Position)(to_y - from_y )) % 2;
        delta = min((Position) half_width, (Position) half_height) - shift;
        
        for (x = 0; x <= delta; x++) {
    	for (y = 1 - shift; y <= delta; y++) {
    	    quad1 = GetBit(BW->bitmap.image, 
    			   from_x + (Position)half_width + x, 
    			   from_y + (Position)half_height + y);
    	    quad2 = GetBit(BW->bitmap.image, 
    			   from_x + (Position)half_width + y, 
    			   from_y + (Position)half_height - shift - x);
    	    quad3 = GetBit(BW->bitmap.image, 
    			   from_x + (Position)half_width - shift - x, 
    			   from_y + (Position)half_height - shift - y);
    	    quad4 = GetBit(BW->bitmap.image, 
    			   from_x + (Position)half_width - shift - y, 
    			   from_y + (Position)half_height + x);
    
    	    if (quad1 != quad4)
    		InvertPoint(BW, 
    			    from_x + (Position)half_width + x, 
    			    from_y + (Position)half_height + y);
    	    if (quad2 != quad1)
    		InvertPoint(BW, 
    			    from_x + (Position)half_width + y, 
    			    from_y + (Position)half_height - shift - x);
    	    if (quad3 != quad2)
    		InvertPoint(BW, 
    			    from_x + (Position)half_width - shift - x,
    			    from_y + (Position)half_height - shift - y);
    	    if (quad4 != quad3)
    		InvertPoint(BW, 
    			    from_x + (Position)half_width - shift - y, 
    			    from_y + (Position)half_height + x);
    	}
        }
        
        if (QuerySet(BW->bitmap.hot.x, BW->bitmap.hot.y)
    	&&
    	!BWQueryMarked(w)) {
    	hot.x = BW->bitmap.hot.x - half_width;
    	hot.y = BW->bitmap.hot.y - half_height;
    	if (hot.x >= 0) hot.x += shift;
    	if (hot.y >= 0) hot.y += shift;
    	tmp = hot.x;
    	hot.x = hot.y;
    	hot.y = - tmp;
    	if (hot.x > 0) hot.x -= shift;
    	if (hot.y > 0) hot.y -= shift;
    	hot.x += half_width;
    	hot.y += half_height;
    	if (QueryInBitmap(BW, hot.x, hot.y))
    	    BWSetHotSpot(w, hot.x, hot.y);
        }
    }
    
    
    void 
    CopyImageData(XImage *source, XImage *destination, 
    	      Position from_x, Position from_y, 
    	      Position to_x, Position to_y, 
    	      Position at_x, Position at_y)
    {
        Position x, y, delta_x, delta_y;
        
        delta_x = to_x - from_x + 1;
        delta_y = to_y - from_y + 1;
        
        for (x = 0; x < delta_x; x++)
    	for (y = 0; y < delta_y; y++)
    	    if (GetBit(source, from_x + x, from_y + y))
    		SetBit(destination, at_x + x, at_y + y);
    	    else
    		ClearBit(destination, at_x + x, at_y + y);
    }
          
    XImage *
    ConvertToBitmapImage(BitmapWidget BW, XImage *image)
    {
        XImage *bitmap_image;
        char   *data;
        Position x, y;
        
        data = CreateCleanData(Length(image->width, image->height));
        bitmap_image = CreateBitmapImage(BW, data, 
    				     (Dimension) image->width, 
    				     (Dimension) image->height);
    
        for (x = 0; x < min(image->width, bitmap_image->width); x++)
    	for (y = 0; y < min(image->height, bitmap_image->height); y++)
    	    if ((XGetPixel(image, x, y) != 0) != GetBit(bitmap_image, x, y))
    		InvertBit(bitmap_image, x, y);
    
        return bitmap_image;
    }
    
    void 
    TransferImageData(XImage *source, XImage *destination)
    {
        Position x, y;
        
        for (x = 0; x < min(source->width, destination->width); x++)
    	for (y = 0; y < min(source->height, destination->height); y++)
    	    if (GetBit(source, x, y) != GetBit(destination, x, y))
    		InvertBit(destination, x, y);
    }
    
    void 
    BWStore(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        Dimension width, height;
        char *storage_data;
    
        if (QuerySet(BW->bitmap.mark.from_x, BW->bitmap.mark.from_y)) {
    
    	DestroyBitmapImage(&BW->bitmap.storage);
    
    	width = BW->bitmap.mark.to_x - BW->bitmap.mark.from_x + 1;
    	height = BW->bitmap.mark.to_y - BW->bitmap.mark.from_y + 1;
    	
    	storage_data = CreateCleanData(Length(width, height));
    
    	BW->bitmap.storage = CreateBitmapImage(BW,
    					       storage_data,
    					       width, height);
    
    	CopyImageData(BW->bitmap.image, BW->bitmap.storage,
    		      BW->bitmap.mark.from_x,  BW->bitmap.mark.from_y,
    		      BW->bitmap.mark.to_x,  BW->bitmap.mark.to_y,
    		      0, 0);
        }
    }
    
    void 
    BWClearMarked(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        if (QuerySet(BW->bitmap.mark.from_x, BW->bitmap.mark.from_y))
    	BWDrawFilledRectangle(w,
    			      BW->bitmap.mark.from_x,
    			      BW->bitmap.mark.from_y,
    			      BW->bitmap.mark.to_x,
    			      BW->bitmap.mark.to_y,
    			      Clear);
    }
    
    
    void 
    BWDragMarked(Widget w, Position at_x, Position at_y)
    {
        BitmapWidget BW = (BitmapWidget) w;
    
        if (QuerySet(BW->bitmap.mark.from_x, BW->bitmap.mark.from_y))
    	BWDrawRectangle(w, 
    			at_x, at_y, 
    			at_x + BW->bitmap.mark.to_x - BW->bitmap.mark.from_x,
    			at_y + BW->bitmap.mark.to_y - BW->bitmap.mark.from_y,
    			Highlight);
    }
    
    void 
    BWDragStored(Widget w, Position at_x, Position at_y)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        if (BW->bitmap.storage)
    	BWDrawRectangle(w, 
    			at_x, at_y,
    			at_x + BW->bitmap.storage->width - 1,
    			at_y + BW->bitmap.storage->height - 1,
    			Highlight);
    }
    
    static void 
    DrawImageData(BitmapWidget BW, XImage *image, 
    	      Position at_x, Position at_y, int value)
    {
        Position x, y;
        Boolean  C, S, I, H;
        bit      A, B;
    
        C = value == Clear;
        S = value == Set;
        I = value == Invert;
        H = value == Highlight;
    
        for (x = 0; x < image->width; x++) 
    	for (y = 0; y < image->height; y++) {
    	    A = GetBit(image, x, y);
    	    B = GetBit(BW->bitmap.image, at_x + x, at_y + y);
    	    if ((A & C) | ((A | B) & S) | ((A ^ B) & I) | ((A | B) & H))
    		value = (A & H) ? Highlight : Set;
    	    else
    		value = Clear;
    	    BWDrawPoint((Widget) BW, 
    			 at_x + x, at_y + y, 
    			 value);
    	}
    }
    
    void 
    BWRestore(Widget w, Position at_x, Position at_y, int value)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        if (BW->bitmap.storage) {
          DrawImageData(BW, BW->bitmap.storage, at_x, at_y, value);
          /*DestroyBitmapImage(&BW->bitmap.storage);*/
        }
    }
    
    void 
    BWCopy(Widget w, Position at_x, Position at_y, int value)
    {
        BitmapWidget BW = (BitmapWidget) w;
        XImage *storage;
        char *storage_data;
        Dimension width, height;
    
        if (QuerySet(BW->bitmap.mark.from_x, BW->bitmap.mark.from_y)) {
    
    	width = BW->bitmap.mark.to_x - BW->bitmap.mark.from_x + 1;
    	height = BW->bitmap.mark.to_y - BW->bitmap.mark.from_y + 1;
    	
    	storage_data = CreateCleanData(Length(width, height));
    
    	storage = CreateBitmapImage(BW, storage_data, width, height);
    
    	CopyImageData(BW->bitmap.image, storage,
    		      BW->bitmap.mark.from_x,  BW->bitmap.mark.from_y,
    		      BW->bitmap.mark.to_x,  BW->bitmap.mark.to_y,
    		      0, 0);
    
    	DrawImageData(BW, storage, at_x, at_y, value);
    
    	DestroyBitmapImage(&storage);
        }
    }
    
    /* void BWMark(); */
    
    void 
    BWMove(Widget w, Position at_x, Position at_y, int value)
    {
        BitmapWidget BW = (BitmapWidget) w;
        XImage *storage;
        char *storage_data;
        Dimension width, height;
    
        if (QuerySet(BW->bitmap.mark.from_x, BW->bitmap.mark.from_y)) {
    
    	width = BW->bitmap.mark.to_x - BW->bitmap.mark.from_x + 1;
    	height = BW->bitmap.mark.to_y - BW->bitmap.mark.from_y + 1;
    	
    	storage_data = CreateCleanData(Length(width, height));
    
    	storage = CreateBitmapImage(BW, storage_data, width, height);
    
    	CopyImageData(BW->bitmap.image, storage,
    		      BW->bitmap.mark.from_x,  BW->bitmap.mark.from_y,
    		      BW->bitmap.mark.to_x,  BW->bitmap.mark.to_y,
    		      0, 0);
    
    	BWDrawFilledRectangle(w,
    			      BW->bitmap.mark.from_x, BW->bitmap.mark.from_y,
    			      BW->bitmap.mark.to_x, BW->bitmap.mark.to_y,
    			      Clear);
    
    	DrawImageData(BW, storage, at_x, at_y, value);
    
    	BWMark(w, at_x, at_y,
    	     at_x + BW->bitmap.mark.to_x - BW->bitmap.mark.from_x,
    	     at_y + BW->bitmap.mark.to_y - BW->bitmap.mark.from_y);
    
    	DestroyBitmapImage(&storage);
        }
    }
    
    void 
    BWRedrawMark(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        if (QuerySet(BW->bitmap.mark.from_x, BW->bitmap.mark.from_y)) 
    	XFillRectangle(XtDisplay(BW), XtWindow(BW), BW->bitmap.highlighting_gc,
    		       InWindowX(BW, BW->bitmap.mark.from_x), 
    		       InWindowY(BW, BW->bitmap.mark.from_y), 
    		       InWindowX(BW, BW->bitmap.mark.to_x + 1) - 
    		       InWindowX(BW, BW->bitmap.mark.from_x),
    		       InWindowY(BW, BW->bitmap.mark.to_y + 1) -
    		       InWindowY(BW, BW->bitmap.mark.from_y));
    }
    
    void 
    BWStoreToBuffer(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        
        memmove( BW->bitmap.buffer->data, BW->bitmap.image->data, 
    	  Length(BW->bitmap.image->width, BW->bitmap.image->height));
    
        BW->bitmap.buffer_hot = BW->bitmap.hot;
        BW->bitmap.buffer_mark = BW->bitmap.mark;
    }
    
    void 
    BWUnmark(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
    
        BW->bitmap.buffer_mark = BW->bitmap.mark;
    
        if (QuerySet(BW->bitmap.mark.from_x, BW->bitmap.mark.from_y)) {
    	XFillRectangle(XtDisplay(BW), XtWindow(BW), BW->bitmap.highlighting_gc,
    		       InWindowX(BW, BW->bitmap.mark.from_x), 
    		       InWindowY(BW, BW->bitmap.mark.from_y), 
    		       InWindowX(BW, BW->bitmap.mark.to_x + 1) - 
    		       InWindowX(BW, BW->bitmap.mark.from_x),
    		       InWindowY(BW, BW->bitmap.mark.to_y + 1) -
    		       InWindowY(BW, BW->bitmap.mark.from_y));
        
    	BW->bitmap.mark.from_x = BW->bitmap.mark.from_y = NotSet;
    	BW->bitmap.mark.to_x = BW->bitmap.mark.to_y = NotSet;
        }
    }
    
    void 
    BWMark(Widget w, Position from_x, Position from_y, 
           Position to_x, Position to_y)
    {
        BitmapWidget BW = (BitmapWidget) w;
    
        BWUnmark(w);
        
        if (QuerySet(from_x, from_y)) {
    	if ((from_x == to_x) && (from_y == to_y)) {
    	    /*
    	      BW->bitmap.mark.from_x = 0;
    	      BW->bitmap.mark.from_y = 0;
    	      BW->bitmap.mark.to_x = BW->bitmap.image->width - 1;
    	      BW->bitmap.mark.to_y = BW->bitmap.image->height - 1;
    	      */
    	    return;
    	}
    	else {
    	    QuerySwap(from_x, to_x);
    	    QuerySwap(from_y, to_y);
    	    from_x = max(0, from_x);
    	    from_y = max(0, from_y);
    	    to_x = min(BW->bitmap.image->width - 1, to_x);
    	    to_y = min(BW->bitmap.image->height - 1, to_y);
    	    
    	    BW->bitmap.mark.from_x = from_x;
    	    BW->bitmap.mark.from_y = from_y;
    	    BW->bitmap.mark.to_x = to_x;
    	    BW->bitmap.mark.to_y = to_y;
    	}
    	
    	XFillRectangle(XtDisplay(BW), XtWindow(BW), BW->bitmap.highlighting_gc,
    		       InWindowX(BW, BW->bitmap.mark.from_x),
    		       InWindowY(BW, BW->bitmap.mark.from_y), 
    		       InWindowX(BW, BW->bitmap.mark.to_x + 1) -
    		       InWindowX(BW, BW->bitmap.mark.from_x),
    		       InWindowY(BW, BW->bitmap.mark.to_y +1) - 
    		       InWindowY(BW, BW->bitmap.mark.from_y));
        }
    }
    
    void 
    BWMarkAll(Widget w)
    {
      BitmapWidget BW = (BitmapWidget) w;
    
      BWMark(w, 0, 0, BW->bitmap.image->width - 1, BW->bitmap.image->height - 1);
    }
    
    void 
    BWUndo(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
        Position x, y;
        char *tmp_data;
        XPoint tmp_hot;
        BWArea tmp_mark;
        
        tmp_data = BW->bitmap.image->data;
        BW->bitmap.image->data = BW->bitmap.buffer->data;
        BW->bitmap.buffer->data = tmp_data;
    
        tmp_hot = BW->bitmap.hot;
        tmp_mark = BW->bitmap.mark;
        
        for (x = 0; x < BW->bitmap.image->width; x++)
    	for (y = 0; y < BW->bitmap.image->height; y++)
    	 if (GetBit(BW->bitmap.image, x, y) != GetBit(BW->bitmap.buffer, x, y))
    	     DrawSquare(BW, x, y);
    
        BWSetHotSpot(w, BW->bitmap.buffer_hot.x, BW->bitmap.buffer_hot.y);
    /*    
        BWMark(w, BW->bitmap.buffer_mark.from_x, BW->bitmap.buffer_mark.from_y,
    	   BW->bitmap.buffer_mark.to_x, BW->bitmap.buffer_mark.to_y);
    */
        BW->bitmap.buffer_hot = tmp_hot;
        BW->bitmap.buffer_mark= tmp_mark;
    
    }
    
    void 
    BWHighlightAxes(Widget w)
    {
        BitmapWidget BW = (BitmapWidget) w;
    
        XDrawLine(XtDisplay(BW), XtWindow(BW),
    	      BW->bitmap.axes_gc,
    	      InWindowX(BW, 0), 
    	      InWindowY(BW, 0),
    	      InWindowX(BW, BW->bitmap.width),
    	      InWindowY(BW, BW->bitmap.height));
        XDrawLine(XtDisplay(BW), XtWindow(BW),
    	      BW->bitmap.axes_gc,
    	      InWindowX(BW, BW->bitmap.width),
    	      InWindowY(BW, 0), 
    	      InWindowX(BW, 0),
    	      InWindowY(BW, BW->bitmap.height));
        XDrawLine(XtDisplay(BW), XtWindow(BW),
    	      BW->bitmap.axes_gc,
    	      InWindowX(BW, 0),
    	      InWindowY(BW, (float)BW->bitmap.height / 2.0),
    	      InWindowX(BW, BW->bitmap.width),
    	      InWindowY(BW, (float)BW->bitmap.height / 2.0));
        XDrawLine(XtDisplay(BW), XtWindow(BW),
    	      BW->bitmap.axes_gc,
    	      InWindowX(BW, (float)BW->bitmap.width / 2.0),
    	      InWindowY(BW, 0),
    	      InWindowX(BW, (float)BW->bitmap.width / 2.0),
    	      InWindowY(BW, BW->bitmap.height));
    }
        
    typedef struct {
        Position *x, *y;
        Dimension *width, *height;
    } Table;
    
    XImage *
    ScaleBitmapImage(BitmapWidget BW, XImage *src, 
    		 double scale_x, double scale_y)
    {
        char *data;
        XImage *dst;
        Table table;    
        Position x, y, w, h;
        Dimension width, height;
        bit pixel;
    
        width = max(rint(scale_x * src->width), 1);
        height = max(rint(scale_y * src->height), 1);
    
        data = CreateCleanData(Length(width, height));
        dst = CreateBitmapImage(BW, data, width, height);
    
        /*
         * It would be nice to check if width or height < 1.0 and
         * average the skipped pixels. But, it is slow as it is now.
         */
        if (scale_x == 1.0 && scale_y == 1.0)
    	memmove( dst->data, src->data, Length(width, height));
        else {
    	table.x = (Position *) XtMalloc(sizeof(Position) * src->width);
    	table.y = (Position *) XtMalloc(sizeof(Position) * src->height);
    	table.width = (Dimension *) XtMalloc(sizeof(Dimension) * src->width);
    	table.height = (Dimension *) XtMalloc(sizeof(Dimension) * src->height);
    	
    	for (x = 0; x < src->width; x++) {
    	    table.x[x] = rint(scale_x * x);
    	    table.width[x] = rint(scale_x * (x + 1)) - rint(scale_x * x);
    	}
    	for (y = 0; y < src->height; y++) {
    	    table.y[y] = rint(scale_y * y);
    	    table.height[y] = rint(scale_y * (y + 1)) - rint(scale_y * y);
    	}
    	
    	for (x = 0; x < src->width; x++)
    	    for (y = 0; y < src->height; y++) {
    	        pixel = GetBit(src, x, y);
    		for (w = 0; (int)w < (int)table.width[x]; w++)
    		    for (h = 0; (int)h < (int)table.height[y]; h++)
    			if (pixel) SetBit(dst, 
    					table.x[x] + w, 
    					table.y[y] + h);
    	    }
    
    	XtFree((char *)table.x);
    	XtFree((char *)table.y);
    	XtFree((char *)table.width);
    	XtFree((char *)table.height);
        }
        
        return (dst);
    }
    
    /*****************************************************************************/