wrlib/xpixmap.c

   1 /* xpixmap.c - Make RImage from Pixmap or XImage
   2  *
   3  * Raster graphics library
   4  *
   5  * Copyright (c) 1997-2003 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 #define NORMALIZE_RED(pixel)    ((rshift>0) ? ((pixel) & rmask) >> rshift \
  49                                         : ((pixel) & rmask) << -rshift)
  50 #define NORMALIZE_GREEN(pixel)  ((gshift>0) ? ((pixel) & gmask) >> gshift \
  51                                         : ((pixel) & gmask) << -gshift)
  52 #define NORMALIZE_BLUE(pixel)   ((bshift>0) ? ((pixel) & bmask) >> bshift \
  53                                         : ((pixel) & bmask) << -bshift)
  54
  55 RImage*
  56 RCreateImageFromXImage(RContext *context, XImage *image, XImage *mask)
  57 {
  58     RImage *img;
  59     int x, y;
  60     unsigned long pixel;
  61     unsigned char *data;
  62     int rshift, gshift, bshift;
  63     int rmask, gmask, bmask;
  64
  65     assert(image!=NULL);
  66     assert(image->format==ZPixmap);
  67     assert(!mask || mask->format==ZPixmap);
  68
  69     img = RCreateImage(image->width, image->height, mask!=NULL);
  70     if (!img) {
  71         return NULL;
  72     }
  73
  74
  75     /* I don't know why, but XGetImage() for pixmaps don't set the
  76      * {red,green,blue}_mask values correctly.
  77      */
  78     if (context->depth==image->depth) {
  79         rmask = context->visual->red_mask;
  80         gmask = context->visual->green_mask;
  81         bmask = context->visual->blue_mask;
  82     } else {
  83         rmask = image->red_mask;
  84         gmask = image->green_mask;
  85         bmask = image->blue_mask;
  86     }
  87
  88     /* how many bits to shift to normalize the color into 8bpp */
  89     rshift = get_shifts(rmask) - 8;
  90     gshift = get_shifts(gmask) - 8;
  91     bshift = get_shifts(bmask) - 8;
  92
  93     data = img->data;
  94
  95     if (image->depth==1) {
  96         for (y = 0; y < image->height; y++) {
  97         for (x = 0; x < image->width; x++) {
  98             pixel = XGetPixel(image, x, y);
  99             if (pixel) {
 100                 *data++ = 0;
 101                 *data++ = 0;
 102                 *data++ = 0;
 103             } else {
 104                 *data++ = 0xff;
 105                 *data++ = 0xff;
 106                 *data++ = 0xff;
 107             }
 108             if (mask) data++;
 109         }
 110         }
 111     } else {
 112         for (y = 0; y < image->height; y++) {
 113         for (x = 0; x < image->width; x++) {
 114             pixel = XGetPixel(image, x, y);
 115             *(data++) = NORMALIZE_RED(pixel);
 116             *(data++) = NORMALIZE_GREEN(pixel);
 117             *(data++) = NORMALIZE_BLUE(pixel);
 118             if (mask) data++;
 119         }
 120         }
 121     }
 122
 123 #define MIN(a,b) ((a)<(b)?(a):(b))
 124     if (mask) {
 125         data = img->data + 3;   /* Skip R, G & B */
 126         for (y = 0; y < MIN(mask->height, image->height); y++) {
 127             for (x = 0; x < MIN(mask->width, image->width); x++) {
 128                 if (mask->width <= image->width && XGetPixel(mask, x, y)) {
 129                     *data = 0xff;
 130                 } else {
 131                     *data = 0;
 132                 }
 133                 data += 4;
 134             }
 135             for (; x < image->width; x++) {
 136                 *data = 0;
 137                 data += 4;
 138             }
 139         }
 140         for (; y < image->height; y++) {
 141             for (x = 0; x < image->width; x++) {
 142                 *data = 0;
 143                 data += 4;
 144             }
 145         }
 146     }
 147     return img;
 148 }
 149
 150
 151
 152 RImage*
 153 RCreateImageFromDrawable(RContext *context, Drawable drawable, Pixmap mask)
 154 {
 155     RImage *image;
 156     XImage *pimg, *mimg;
 157     unsigned int w, h, bar;
 158     int foo;
 159     Window baz;
 160
 161
 162     assert(drawable!=None);
 163
 164     if (!XGetGeometry(context->dpy, drawable, &baz, &foo, &foo,
 165                       &w, &h, &bar, &bar)) {
 166         printf("wrlib: invalid window or pixmap passed to RCreateImageFromPixmap\n");
 167         return NULL;
 168     }
 169     pimg = XGetImage(context->dpy, drawable, 0, 0, w, h, AllPlanes,
 170                      ZPixmap);
 171
 172     if (!pimg) {
 173         RErrorCode = RERR_XERROR;
 174         return NULL;
 175     }
 176     mimg = NULL;
 177     if (mask) {
 178         if (XGetGeometry(context->dpy, mask, &baz, &foo, &foo,
 179                           &w, &h, &bar, &bar)) {
 180             mimg = XGetImage(context->dpy, mask, 0, 0, w, h, AllPlanes,
 181                              ZPixmap);
 182         }
 183     }
 184
 185     image = RCreateImageFromXImage(context, pimg, mimg);
 186
 187     XDestroyImage(pimg);
 188     if (mimg)
 189       XDestroyImage(mimg);
 190
 191     return image;
 192 }