gdk-pixbuf-xlibrgb.c

linux下电话本所依赖的一些图形库

/**
 * xlib_rgb_init_with_depth:
 * @display: X display to use.
 * @screen: Screen to use.
 * @prefDepth: Visual depth to use for color substitution tables.  This must
 * be one of the supported visual depths in the specified @display.
 * 
 * Initializes the XlibRGB machinery with a particular depth you specify,
 * instead of automatically picking the best depth in the display.  This
 * function or xlib_rgb_init() must be called before using any of the other
 * functions in XlibRGB.
 **/
void
xlib_rgb_init_with_depth (Display *display, Screen *screen, int prefDepth)
{
  int i;
  static const int byte_order[1] = { 1 };

  static int initialized = 0;

  if (initialized)
  {
    return;
  }

  initialized = 1;

  /* check endian sanity */
#if G_BYTE_ORDER == G_BIG_ENDIAN
  if (((char *)byte_order)[0] == 1) {
    printf ("xlib_rgb_init: compiled for big endian, but this is a little endian machine.\n\n");
    exit(1);
  }
#else
  if (((char *)byte_order)[0] != 1) {
    printf ("xlib_rgb_init: compiled for little endian, but this is a big endian machine.\n\n");
    exit(1);
  }
#endif

  if (image_info == NULL)
    {
      image_info = malloc(sizeof(XlibRgbInfo));
      memset(image_info, 0, sizeof(XlibRgbInfo));

      image_info->display = display;
      image_info->screen = screen;
      image_info->screen_num = XScreenNumberOfScreen(screen);
      image_info->x_visual_info = NULL;
      image_info->cmap = 0;
      image_info->default_visualid = DefaultVisual(display, image_info->screen_num);
      image_info->default_colormap = DefaultColormap(display, image_info->screen_num);

      image_info->color_pixels = NULL;
      image_info->gray_pixels = NULL;
      image_info->reserved_pixels = NULL;

      image_info->nred_shades = 6;
      image_info->ngreen_shades = 6;
      image_info->nblue_shades = 4;
      image_info->ngray_shades = 24;
      image_info->nreserved = 0;

      image_info->bpp = 0;
      image_info->cmap_alloced = FALSE;
      image_info->gamma_val = 1.0;

      image_info->stage_buf = NULL;

      image_info->own_gc = NULL;
      
      image_info->red_shift = 0;
      image_info->red_prec = 0;
      image_info->green_shift = 0;
      image_info->green_prec = 0;
      image_info->blue_shift = 0;
      image_info->blue_prec = 0;

      if (prefDepth != -1)
        xlib_rgb_choose_visual_for_xprint (prefDepth);
      else
        xlib_rgb_choose_visual ();

      if ((image_info->x_visual_info->class == PseudoColor ||
	   image_info->x_visual_info->class == StaticColor) &&
	  image_info->x_visual_info->depth < 8 &&
	  image_info->x_visual_info->depth >= 3)
	{
	  image_info->cmap = image_info->default_colormap;
	  xlib_rgb_colorcube_222 ();
	}
      else if (image_info->x_visual_info->class == PseudoColor)
	{
	  if (xlib_rgb_install_cmap ||
	      image_info->x_visual_info->visualid != image_info->default_visualid->visualid)
	    {
	      image_info->cmap = XCreateColormap(image_info->display,
						 RootWindow(image_info->display, image_info->screen_num),
						 image_info->x_visual_info->visual,
						 AllocNone);
	      image_info->cmap_alloced = TRUE;
	    }
	  if (!xlib_rgb_do_colormaps ())
	    {
	      image_info->cmap = XCreateColormap(image_info->display,
						 RootWindow(image_info->display, image_info->screen_num),
						 image_info->x_visual_info->visual,
						 AllocNone);
	      image_info->cmap_alloced = TRUE;
	      xlib_rgb_do_colormaps ();
	    }
	  if (xlib_rgb_verbose)
	    printf ("color cube: %d x %d x %d\n",
		    image_info->nred_shades,
		    image_info->ngreen_shades,
		    image_info->nblue_shades);

	  if (!image_info->cmap_alloced)
	      image_info->cmap = image_info->default_colormap;
	}
#ifdef ENABLE_GRAYSCALE
      else if (image_info->x_visual_info->class == GrayScale)
	{
	  image_info->cmap = XCreateColormap(image_info->display,
					     RootWindow(image_info->display, image_info->screen_num),
					     image_info->x_visual_info->visual,
					     AllocNone);
	  xlib_rgb_set_gray_cmap (image_info->cmap);
	  image_info->cmap_alloced = TRUE;
     	}
#endif
      else
	{
	  /* Always install colormap in direct color. */
	  if (image_info->x_visual_info->class != DirectColor && 
	      image_info->x_visual_info->visualid == image_info->default_visualid->visualid)
	    image_info->cmap = image_info->default_colormap;
	  else
	    {
	      image_info->cmap = XCreateColormap(image_info->display,
						 RootWindow(image_info->display, image_info->screen_num),
						 image_info->x_visual_info->visual,
						 AllocNone);
	      image_info->cmap_alloced = TRUE;
	    }
	}

      image_info->bitmap = (image_info->x_visual_info->depth == 1);

      for (i = 0; i < N_IMAGES; i++) {
	if (image_info->bitmap) {
	  /* Use malloc() instead of g_malloc since X will free() this mem */
	  static_image[i] = XCreateImage(image_info->display,
					 image_info->x_visual_info->visual,
					 1,
					 XYBitmap,
					 0, NULL, IMAGE_WIDTH, IMAGE_HEIGHT,
					 8,
					 0);
	  static_image[i]->data = malloc(IMAGE_WIDTH * IMAGE_HEIGHT >> 3);
	  static_image[i]->bitmap_bit_order = MSBFirst;
	  static_image[i]->byte_order = MSBFirst;
	}
	else {
	  static_image[i] = XCreateImage(image_info->display,
					 image_info->x_visual_info->visual,
					 (unsigned int)image_info->x_visual_info->depth,
					 ZPixmap,
					 0, NULL,
					 IMAGE_WIDTH,
					 IMAGE_HEIGHT,
					 32, 0);
	  /* remove this when we are using shared memory.. */
	  static_image[i]->data = malloc((size_t)IMAGE_WIDTH * IMAGE_HEIGHT * image_info->x_visual_info->depth);
	  static_image[i]->bitmap_bit_order = MSBFirst;
	  static_image[i]->byte_order = MSBFirst;
	}
      }
      /* ok, so apparently, image_info->bpp is actually
	 BYTES per pixel.  What fun! */
      switch (static_image[0]->bits_per_pixel) {
      case 1:
      case 8:
	image_info->bpp = 1;
	break;
      case 16:
	image_info->bpp = 2;
	break;
      case 24:
	image_info->bpp = 3;
	break;
      case 32:
	image_info->bpp = 4;
	break;
      }
      xlib_rgb_select_conv (static_image[0], MSB_FIRST);
    }
}

/**
 * xlib_rgb_xpixel_from_rgb:
 * @rgb: 32-bit representation of an RGB value, specified as 0x00RRGGBB.
 * 
 * Converts an RGB triplet into the closest color that XlibRGB visual can
 * handle.
 * 
 * Return value: X pixel value that corresponds to the closest color in the
 * XlibRGB visual and colormap.
 **/
unsigned long
xlib_rgb_xpixel_from_rgb (guint32 rgb)
{
  unsigned long pixel = 0;

  if (image_info->bitmap)
    {
      return ((rgb & 0xff0000) >> 16) +
	((rgb & 0xff00) >> 7) +
	(rgb & 0xff) > 510;
    }
  else if (image_info->x_visual_info->class == PseudoColor)
    pixel = colorcube[((rgb & 0xf00000) >> 12) |
		     ((rgb & 0xf000) >> 8) |
		     ((rgb & 0xf0) >> 4)];
  else if (image_info->x_visual_info->depth < 8 &&
	   image_info->x_visual_info->class == StaticColor)
    {
      pixel = colorcube_d[((rgb & 0x800000) >> 17) |
			 ((rgb & 0x8000) >> 12) |
			 ((rgb & 0x80) >> 7)];
    }
  else if (image_info->x_visual_info->class == TrueColor ||
	   image_info->x_visual_info->class == DirectColor)
    {
#ifdef VERBOSE
      printf ("shift, prec: r %d %d g %d %d b %d %d\n",
	      image_info->red_shift,
	      image_info->red_prec,
	      image_info->green_shift,
	      image_info->green_prec,
	      image_info->blue_shift,
	      image_info->blue_prec);
#endif

      pixel = (((((rgb & 0xff0000) >> 16) >>
		 (8 - image_info->red_prec)) <<
		image_info->red_shift) +
	       ((((rgb & 0xff00) >> 8)  >>
		 (8 - image_info->green_prec)) <<
		image_info->green_shift) +