wmwebcam/minirgb.c

   1 /* minirgb -- simple rgb buffer drawing library for 16, 24 and 32 bit displays
   2  * Copyright (C) 2000 timecop@japan.co.jp
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17  */
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <X11/Xlib.h>
  21 #include <X11/Xutil.h>
  22 #include "minirgb.h"
  23
  24 #undef  MAX
  25 #define MAX(a, b)  (((a) > (b)) ? (a) : (b))
  26
  27 /* local variables */
  28 Display *minirgb_display;                       /* display */
  29 Visual  *minirgb_visual;                        /* visual */
  30 int     minirgb_depth;                          /* display depth */
  31 int     minirgb_ok = 0;                         /* init ok? */
  32
  33 /* local prototypes */
  34 static __inline void rgb_conv_16(unsigned char *ptr, unsigned char r, unsigned char g, unsigned char b, XImage *image);
  35 static __inline void rgb_conv_24(unsigned char *ptr, unsigned char r, unsigned char g, unsigned char b, XImage *image);
  36 static __inline void rgb_conv_32(unsigned char *ptr, unsigned char r, unsigned char g, unsigned char b, XImage *image);
  37
  38 static __inline void rgb_conv_16(unsigned char *ptr, unsigned char r, unsigned char g, unsigned char b, XImage *image)
  39 {
  40     if (image->green_mask & 0x7e0) /* 565 */
  41         *(unsigned short int *)ptr = ((r >> 3) << 11) |
  42                                      ((g >> 2) << 5) |
  43                                      (b >> 3);
  44     else /* 555 untested */
  45         *(unsigned short int *)ptr = ((r >> 3) << 11) |
  46                                      ((g >> 3) << 6) |
  47                                      (b >> 3);
  48 }
  49
  50 static __inline void rgb_conv_24(unsigned char *ptr, unsigned char r, unsigned char g, unsigned char b, XImage *image)
  51 {
  52     /* untested */
  53     *ptr++ = r;
  54     *ptr++ = g;
  55     *ptr = b;
  56 }
  57
  58 static __inline void rgb_conv_32(unsigned char *ptr, unsigned char r, unsigned char g, unsigned char b, XImage *image)
  59 {
  60     if (image->red_mask & 0xff0000)  /* 0888 */
  61         *(unsigned int *)ptr = (r << 16) |
  62                                (g << 8) |
  63                                (b);
  64     else /* 8880 untested */
  65         *(unsigned int *)ptr = (r << 24) |
  66                                (g << 16) |
  67                                (b << 8);
  68 }
  69
  70 int minirgb_init(Display *d)
  71 {
  72     int screen;
  73
  74     minirgb_display = d;
  75     screen = DefaultScreen(minirgb_display);
  76     minirgb_visual = XDefaultVisual(minirgb_display, screen);
  77     minirgb_depth = XDefaultDepth(minirgb_display, screen);
  78     if (minirgb_depth <= 8) {
  79         fprintf(stderr, "minirgb: No support for 8 bit displays\n");
  80         minirgb_ok = 0;
  81         return 1;
  82     } else {
  83         minirgb_ok = 1;
  84         return 0;
  85     }
  86 }
  87
  88 void minirgb_setpixel(MiniRGB *rgb_image, unsigned char *color, unsigned int x, unsigned int y)
  89 {
  90     unsigned char *ptr;
  91
  92     ptr = rgb_image->mem + (y * rgb_image->rowstride * 3) + (x * 3);
  93     *ptr++ = *color++;
  94     *ptr++ = *color++;
  95     *ptr = *color;
  96 }
  97
  98 void minirgb_copy(MiniRGB *from, MiniRGB *to,
  99         unsigned int sx, unsigned int sy, unsigned int w, unsigned int h,
 100         unsigned int dx, unsigned int dy)
 101 {
 102     unsigned int i;
 103     unsigned char *src, *dest;
 104
 105 #ifdef VERBOSE
 106     fprintf(stderr, "minirgb: copy %d, %d (%dx%d) -> %d, %d)\n", sx, sy, w, h, dx, dy);
 107 #endif
 108
 109 #if 0
 110     if (w == 1) { /* special case - dot operations */
 111         src = from->mem + (sy * from->rowstride * 3) + sx * 3;
 112         dest = to->mem + (dy * to->rowstride * 3) + dx * 3;
 113         dest[0] = dest[0] & src[0];
 114         dest[1] = dest[1] & src[1];
 115         dest[2] = dest[2] & src[2];
 116         return;
 117     }
 118 #endif
 119
 120     for (i = 0; i < h; i++) {
 121         src = from->mem + ((sy + i) * from->rowstride * 3) + sx * 3;
 122         dest = to->mem + ((dy + i) * to->rowstride * 3) + dx * 3;
 123         memcpy(dest, src, w * 3);
 124     }
 125 }
 126
 127 void minirgb_new(MiniRGB *image, unsigned int width, unsigned int height)
 128 {
 129     image->width = width;
 130     image->height = height;
 131     image->rowstride = width;
 132     image->mem = calloc(1, width * height * 3);
 133 }
 134
 135 void minirgb_draw(Window drawable, GC gc, int x, int y, int width,
 136                        int height, MiniRGB *rgb_image)
 137 {
 138     XImage *image = NULL;
 139     unsigned int bpp;
 140     unsigned int x0, y0;
 141     unsigned char *ptr, *col;
 142     void (*conv) (unsigned char *, unsigned char, unsigned char, unsigned char, XImage *) = NULL;
 143
 144     if (!minirgb_ok)
 145         return;
 146
 147     image = XCreateImage(minirgb_display, minirgb_visual, minirgb_depth, ZPixmap, 0, 0, width, height, 32, 0);
 148     bpp = (image->bits_per_pixel + 7) / 8;
 149     switch (bpp) {
 150         case 2:
 151             conv = rgb_conv_16;
 152             break;
 153         case 3:
 154             conv = rgb_conv_24;
 155             break;
 156         case 4:
 157             conv = rgb_conv_32;
 158             break;
 159     }
 160 #ifdef VERBOSE
 161     printf("minirgb: image %p %dx%d (bpp: %d, bpl: %d)\n", image, width, height, bpp, image->bytes_per_line);
 162 #endif
 163     image->data = malloc(image->bytes_per_line * height);
 164     if (!image->data) {
 165         fprintf(stderr, "minirgb: allocation error\n");
 166         XDestroyImage(image);
 167         return;
 168     }
 169
 170     for (y0 = 0; y0 < height; y0++) {
 171         for (x0 = 0; x0 < width; x0++) {
 172             col = rgb_image->mem + (y0 * rgb_image->rowstride * 3 + x0 * 3);
 173             ptr = image->data + (y0 * image->bytes_per_line + x0 * bpp);
 174             conv(ptr, col[0], col[1], col[2], image);
 175         }
 176     }
 177     /* draw image onto drawable */
 178     XPutImage(minirgb_display, drawable, gc, image, 0, 0, x, y, width, height);
 179     XDestroyImage(image);
 180 }