wrlib/xpixmap.c

   1 /* xpixmap.c - Make RImage from Pixmap or XImage
   2  *
   3  *  Raster graphics library
   4  *
   5  *  Copyright (c) 1997 Alfredo K. Kojima
   6  *
   7  *  This library is free software; you can redistribute it and/or
   8  *  modify it under the terms of the GNU Library General Public
   9  *  License as published by the Free Software Foundation; either
  10  *  version 2 of the License, or (at your option) any later version.
  11  *
  12  *  This library is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  *  Library General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU Library General Public
  18  *  License along with this library; if not, write to the Free
  19  *  Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22
  23 #include <config.h>
  24
  25 #include <X11/Xlib.h>
  26 #include <X11/Xutil.h>
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <assert.h>
  31
  32 #include "wraster.h"
  33
  34
  35
  36 static int
  37 get_shifts(unsigned long mask)
  38 {
  39     int i=0;
  40
  41     while (mask) {
  42         mask>>=1;
  43         i++;
  44     }
  45     return i;
  46 }
  47
  48
  49 RImage*
  50 RCreateImageFromXImage(RContext *context, XImage *image, XImage *mask)
  51 {
  52     RImage *img;
  53     int x, y;
  54     unsigned long pixel;
  55     unsigned char *data;
  56     int rshift, gshift, bshift;
  57     int rmask, gmask, bmask;
  58
  59     assert(image!=NULL);
  60     assert(image->format==ZPixmap);
  61     assert(!mask || mask->format==ZPixmap);
  62
  63     img = RCreateImage(image->width, image->height, mask!=NULL);
  64     if (!img) {
  65         return NULL;
  66     }
  67
  68
  69     /* I don't know why, but XGetImage() for pixmaps don't set the
  70      * {red,green,blue}_mask values correctly.
  71      */
  72     if (context->depth==image->depth) {
  73         rmask = context->visual->red_mask;
  74         gmask = context->visual->green_mask;
  75         bmask = context->visual->blue_mask;
  76     } else {
  77         rmask = image->red_mask;
  78         gmask = image->green_mask;
  79         bmask = image->blue_mask;
  80     }
  81
  82     /* how many bits to shift to normalize the color into 8bpp */
  83     rshift = get_shifts(rmask) - 8;
  84     gshift = get_shifts(gmask) - 8;
  85     bshift = get_shifts(bmask) - 8;
  86
  87     data = img->data;
  88
  89 #define NORMALIZE_RED(pixel)    ((rshift>0) ? ((pixel) & rmask) >> rshift \
  90                                         : ((pixel) & rmask) << -rshift)
  91 #define NORMALIZE_GREEN(pixel)  ((gshift>0) ? ((pixel) & gmask) >> gshift \
  92                                         : ((pixel) & gmask) << -gshift)
  93 #define NORMALIZE_BLUE(pixel)   ((bshift>0) ? ((pixel) & bmask) >> bshift \
  94                                         : ((pixel) & bmask) << -bshift)
  95
  96     if (image->depth==1) {
  97         for (y = 0; y < image->height; y++) {
  98             for (x = 0; x < image->width; x++) {
  99                 pixel = XGetPixel(image, x, y);
 100                 if (pixel) {
 101                     *data++ = 0;
 102                     *data++ = 0;
 103                     *data++ = 0;
 104                 } else {
 105                     *data++ = 0xff;
 106                     *data++ = 0xff;
 107                     *data++ = 0xff;
 108                 }
 109                 if (mask)
 110                     *data++ = 0;
 111             }
 112         }
 113     } else {
 114         for (y = 0; y < image->height; y++) {
 115             for (x = 0; x < image->width; x++) {
 116                 pixel = XGetPixel(image, x, y);
 117                 *(data++) = NORMALIZE_RED(pixel);
 118                 *(data++) = NORMALIZE_GREEN(pixel);
 119                 *(data++) = NORMALIZE_BLUE(pixel);
 120                 if (mask)
 121                     *(data++) = 0;
 122             }
 123         }
 124     }
 125
 126     data = img->data;
 127
 128 #define MIN(a,b) ((a)<(b)?(a):(b))
 129     if (mask) {
 130         for (y = 0; y < MIN(mask->height, image->height); y++) {
 131             for (x = 0; x < image->width; x++) {
 132
 133                 data += 3;      /* Skip R, G & B */
 134
 135                 if (mask->width <= image->width && XGetPixel(mask, x, y)) {
 136                     *(data++) = 0xff;
 137                 } else {
 138                     *(data++) = 0;
 139                 }
 140             }
 141         }
 142     }
 143     return img;
 144 }
 145
 146
 147
 148 RImage*
 149 RCreateImageFromDrawable(RContext *context, Drawable drawable, Pixmap mask)
 150 {
 151     RImage *image;
 152     XImage *pimg, *mimg;
 153     unsigned int w, h, bar;
 154     int foo;
 155     Window baz;
 156
 157
 158     assert(drawable!=None);
 159
 160     if (!XGetGeometry(context->dpy, drawable, &baz, &foo, &foo,
 161                       &w, &h, &bar, &bar)) {
 162         printf("wrlib:invalid window or pixmap passed to RCreateImageFromPixmap\n");
 163         return NULL;
 164     }
 165     pimg = XGetImage(context->dpy, drawable, 0, 0, w, h, AllPlanes,
 166                      ZPixmap);
 167
 168     if (!pimg) {
 169         RErrorCode = RERR_XERROR;
 170         return NULL;
 171     }
 172     mimg = NULL;
 173     if (mask) {
 174         if (XGetGeometry(context->dpy, mask, &baz, &foo, &foo,
 175                           &w, &h, &bar, &bar)) {
 176             mimg = XGetImage(context->dpy, mask, 0, 0, w, h, AllPlanes,
 177                              ZPixmap);
 178         }
 179     }
 180
 181     image = RCreateImageFromXImage(context, pimg, mimg);
 182
 183     XDestroyImage(pimg);
 184     if (mimg)
 185       XDestroyImage(mimg);
 186
 187     return image;
 188 }