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 *r, *g, *b, *a;
  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     r = img->data[0];
  88     g = img->data[1];
  89     b = img->data[2];
  90     a = img->data[3];
  91
  92 #define NORMALIZE_RED(pixel)    ((rshift>0) ? ((pixel) & rmask) >> rshift \
  93                                         : ((pixel) & rmask) << -rshift)
  94 #define NORMALIZE_GREEN(pixel)  ((gshift>0) ? ((pixel) & gmask) >> gshift \
  95                                         : ((pixel) & gmask) << -gshift)
  96 #define NORMALIZE_BLUE(pixel)   ((bshift>0) ? ((pixel) & bmask) >> bshift \
  97                                         : ((pixel) & bmask) << -bshift)
  98
  99     if (image->depth==1) {
 100         for (y = 0; y < image->height; y++) {
 101             for (x = 0; x < image->width; x++) {
 102                 pixel = XGetPixel(image, x, y);
 103                 if (pixel) {
 104                     *(r++) = *(g++) = *(b++) = 0;
 105                 } else {
 106                     *(r++) = *(g++) = *(b++) = 0xff;
 107                 }
 108             }
 109         }
 110     } else {
 111         for (y = 0; y < image->height; y++) {
 112             for (x = 0; x < image->width; x++) {
 113                 pixel = XGetPixel(image, x, y);
 114                 *(r++) = NORMALIZE_RED(pixel);
 115                 *(g++) = NORMALIZE_GREEN(pixel);
 116                 *(b++) = NORMALIZE_BLUE(pixel);
 117             }
 118         }
 119     }
 120
 121     if (mask && a) {
 122         for (y = 0; y < mask->height; y++) {
 123             for (x = 0; x < mask->width; x++) {
 124                 if (XGetPixel(mask, x, y)) {
 125                     *(a++) = 0xff;
 126                 } else {
 127                     *(a++) = 0;
 128                 }
 129             }
 130         }
 131     }
 132     return img;
 133 }
 134
 135
 136
 137 RImage*
 138 RCreateImageFromDrawable(RContext *context, Drawable drawable, Pixmap mask)
 139 {
 140     RImage *image;
 141     XImage *pimg, *mimg;
 142     unsigned int w, h, bar;
 143     int foo;
 144     Window baz;
 145
 146
 147     assert(drawable!=None);
 148
 149     if (!XGetGeometry(context->dpy, drawable, &baz, &foo, &foo,
 150                       &w, &h, &bar, &bar)) {
 151         printf("wrlib:invalid window or pixmap passed to RCreateImageFromPixmap\n");
 152         return NULL;
 153     }
 154     pimg = XGetImage(context->dpy, drawable, 0, 0, w, h, AllPlanes,
 155                      ZPixmap);
 156
 157     if (!pimg) {
 158         RErrorCode = RERR_XERROR;
 159         return NULL;
 160     }
 161     mimg = NULL;
 162     if (mask) {
 163         if (XGetGeometry(context->dpy, mask, &baz, &foo, &foo,
 164                           &w, &h, &bar, &bar)) {
 165             mimg = XGetImage(context->dpy, mask, 0, 0, w, h, AllPlanes,
 166                              ZPixmap);
 167         }
 168     }
 169
 170     image = RCreateImageFromXImage(context, pimg, mimg);
 171
 172     XDestroyImage(pimg);
 173     if (mimg)
 174       XDestroyImage(mimg);
 175
 176     return image;
 177 }