gdkcolor.c

gtk是linux一款强大的夸平台的图形化开发工具

	  private->info[pixel].ref_count--;

	  if (private->info[pixel].ref_count == 0)
	    {
	      pixels[npixels++] = pixel;
	      if (!(private->info[pixel].flags & GDK_COLOR_WRITEABLE))
		g_hash_table_remove (private->hash, &colormap->colors[pixel]);
	      private->info[pixel].flags = 0;
	    }
	}
    }

  if (npixels)
    XFreeColors (private->xdisplay, private->xcolormap,
		 pixels, npixels, 0);

  g_free (pixels);
}

/********************
 * Color allocation *
 ********************/

/* Try to allocate a single color using XAllocColor. If it succeeds,
 * cache the result in our colormap, and store in ret.
 */
static gboolean 
gdk_colormap_alloc1 (GdkColormap *colormap,
		     GdkColor    *color,
		     GdkColor    *ret)
{
  GdkColormapPrivate *private;
  XColor xcolor;

  private = (GdkColormapPrivate*) colormap;

  xcolor.red = color->red;
  xcolor.green = color->green;
  xcolor.blue = color->blue;
  xcolor.pixel = color->pixel;
  xcolor.flags = DoRed | DoGreen | DoBlue;

  if (XAllocColor (private->xdisplay, private->xcolormap, &xcolor))
    {
      ret->pixel = xcolor.pixel;
      ret->red = xcolor.red;
      ret->green = xcolor.green;
      ret->blue = xcolor.blue;
      
      if (ret->pixel < colormap->size)
	{
	  if (private->info[ret->pixel].ref_count) /* got a duplicate */
	    {
	      XFreeColors (private->xdisplay, private->xcolormap,
			   &ret->pixel, 1, 0);
	    }
	  else
	    {
	      colormap->colors[ret->pixel] = *color;
	      colormap->colors[ret->pixel].pixel = ret->pixel;
	      private->info[ret->pixel].ref_count = 1;

	      g_hash_table_insert (private->hash,
				   &colormap->colors[ret->pixel],
				   &colormap->colors[ret->pixel]);
	    }
	}
      return TRUE;
    }
  else
    {
      return FALSE;
    }
}

static gint
gdk_colormap_alloc_colors_writeable (GdkColormap *colormap,
				     GdkColor    *colors,
				     gint         ncolors,
				     gboolean     writeable,
				     gboolean     best_match,
				     gboolean    *success)
{
  GdkColormapPrivate *private;
  gulong *pixels;
  Status status;
  gint i, index;

  private = (GdkColormapPrivate*) colormap;

  if (private->private_val)
    {
      index = 0;
      for (i=0; i<ncolors; i++)
	{
	  while ((index < colormap->size) && (private->info[index].ref_count != 0))
	    index++;
	  
	  if (index < colormap->size)
	    {
	      colors[i].pixel = index;
	      success[i] = TRUE;
	      private->info[index].ref_count++;
	      private->info[i].flags |= GDK_COLOR_WRITEABLE;
	    }
	  else
	    break;
	}
      return i;
    }
  else
    {
      pixels = g_new (gulong, ncolors);
      /* Allocation of a writeable color cells */
      
      status =  XAllocColorCells (private->xdisplay, private->xcolormap,
				  FALSE, NULL, 0, pixels, ncolors);
      if (status)
	{
	  for (i=0; i<ncolors; i++)
	    {
	      colors[i].pixel = pixels[i];
	      private->info[pixels[i]].ref_count++;
	      private->info[pixels[i]].flags |= GDK_COLOR_WRITEABLE;
	    }
	}
      
      g_free (pixels);

      return status ? ncolors : 0; 
    }
}

static gint
gdk_colormap_alloc_colors_private (GdkColormap *colormap,
				   GdkColor    *colors,
				   gint         ncolors,
				   gboolean     writeable,
				   gboolean     best_match,
				   gboolean    *success)
{
  GdkColormapPrivate *private;
  gint i, index;
  XColor *store = g_new (XColor, ncolors);
  gint nstore = 0;
  gint nremaining = 0;
  
  private = (GdkColormapPrivate*) colormap;
  index = -1;

  /* First, store the colors we have room for */

  index = 0;
  for (i=0; i<ncolors; i++)
    {
      if (!success[i])
	{
	  while ((index < colormap->size) && (private->info[index].ref_count != 0))
	    index++;

	  if (index < colormap->size)
	    {
	      store[nstore].red = colors[i].red;
	      store[nstore].blue = colors[i].blue;
	      store[nstore].green = colors[i].green;
	      store[nstore].pixel = index;
	      nstore++;

	      success[i] = TRUE;

	      colors[i].pixel = index;
	      private->info[index].ref_count++;
	    }
	  else
	    nremaining++;
	}
    }
  
  XStoreColors (private->xdisplay, private->xcolormap, store, nstore);
  g_free (store);

  if (nremaining > 0 && best_match)
    {
      /* Get best matches for remaining colors */

      gchar *available = g_new (gchar, colormap->size);
      for (i = 0; i < colormap->size; i++)
	available[i] = TRUE;

      for (i=0; i<ncolors; i++)
	{
	  if (!success[i])
	    {
	      index = gdk_colormap_match_color (colormap, 
						&colors[i], 
						available);
	      if (index != -1)
		{
		  colors[i] = colormap->colors[index];
		  private->info[index].ref_count++;

		  success[i] = TRUE;
		  nremaining--;
		}
	    }
	}
      g_free (available);
    }

  return (ncolors - nremaining);
}

static gint
gdk_colormap_alloc_colors_shared (GdkColormap *colormap,
				  GdkColor    *colors,
				  gint         ncolors,
				  gboolean     writeable,
				  gboolean     best_match,
				  gboolean    *success)
{
  GdkColormapPrivate *private;
  gint i, index;
  gint nremaining = 0;
  gint nfailed = 0;

  private = (GdkColormapPrivate*) colormap;
  index = -1;

  for (i=0; i<ncolors; i++)
    {
      if (!success[i])
	{
	  if (gdk_colormap_alloc1 (colormap, &colors[i], &colors[i]))
	    success[i] = TRUE;
	  else
	    nremaining++;
	}
    }


  if (nremaining > 0 && best_match)
    {
      gchar *available = g_new (gchar, colormap->size);
      for (i = 0; i < colormap->size; i++)
	available[i] = ((private->info[i].ref_count == 0) ||
			!(private->info[i].flags && GDK_COLOR_WRITEABLE));
      gdk_colormap_sync (colormap, FALSE);
      
      while (nremaining > 0)
	{
	  for (i=0; i<ncolors; i++)
	    {
	      if (!success[i])
		{
		  index = gdk_colormap_match_color (colormap, &colors[i], available);
		  if (index != -1)
		    {
		      if (private->info[index].ref_count)
			{
			  private->info[index].ref_count++;
			  colors[i] = colormap->colors[index];
			  success[i] = TRUE;
			  nremaining--;
			}
		      else
			{
			  if (gdk_colormap_alloc1 (colormap, 
						   &colormap->colors[index],
						   &colors[i]))
			    {
			      success[i] = TRUE;
			      nremaining--;
			      break;
			    }
			  else
			    {
			      available[index] = FALSE;
			    }
			}
		    }
		  else
		    {
		      nfailed++;
		      nremaining--;
		      success[i] = 2; /* flag as permanent failure */
		    }
		}
	    }
	}
      g_free (available);
    }

  /* Change back the values we flagged as permanent failures */
  if (nfailed > 0)
    {
      for (i=0; i<ncolors; i++)
	if (success[i] == 2)
	  success[i] = FALSE;
      nremaining = nfailed;
    }
  
  return (ncolors - nremaining);
}

static gint
gdk_colormap_alloc_colors_pseudocolor (GdkColormap *colormap,
				       GdkColor    *colors,
				       gint         ncolors,
				       gboolean     writeable,
				       gboolean     best_match,
				       gboolean    *success)
{
  GdkColormapPrivate *private;
  GdkColor *lookup_color;
  gint i;
  gint nremaining = 0;

  private = (GdkColormapPrivate*) colormap;

  /* Check for an exact match among previously allocated colors */

  for (i=0; i<ncolors; i++)
    {
      if (!success[i])
	{
	  lookup_color = g_hash_table_lookup (private->hash, &colors[i]);
	  if (lookup_color)
	    {
	      private->info[lookup_color->pixel].ref_count++;
	      colors[i].pixel = lookup_color->pixel;
	      success[i] = TRUE;
	    }
	  else
	    nremaining++;
	}
    }

  /* If that failed, we try to allocate a new color, or approxmiate
   * with what we can get if best_match is TRUE.
   */
  if (nremaining > 0)
    {
      if (private->private_val)
	return gdk_colormap_alloc_colors_private (colormap, colors, ncolors, writeable, best_match, success);
      else
	return gdk_colormap_alloc_colors_shared (colormap, colors, ncolors, writeable, best_match, success);
    }
  else
    return 0;
}

gint
gdk_colormap_alloc_colors (GdkColormap *colormap,
			   GdkColor    *colors,
			   gint         ncolors,
			   gboolean     writeable,
			   gboolean     best_match,
			   gboolean    *success)
{
  GdkColormapPrivate *private;
  GdkVisual *visual;
  gint i;
  gint nremaining = 0;
  XColor xcolor;

  g_return_val_if_fail (colormap != NULL, FALSE);
  g_return_val_if_fail (colors != NULL, FALSE);

  private = (GdkColormapPrivate*) colormap;

  for (i=0; i<ncolors; i++)
    {
      success[i] = FALSE;
    }

  switch (private->visual->type)
    {
    case GDK_VISUAL_PSEUDO_COLOR:
    case GDK_VISUAL_GRAYSCALE:
      if (writeable)
	return gdk_colormap_alloc_colors_writeable (colormap, colors, ncolors,
						    writeable, best_match, success);
      else
	return gdk_colormap_alloc_colors_pseudocolor (colormap, colors, ncolors,
						    writeable, best_match, success);
      break;

    case GDK_VISUAL_DIRECT_COLOR:
    case GDK_VISUAL_TRUE_COLOR:
      visual = private->visual;

      for (i=0; i<ncolors; i++)
	{
	  colors[i].pixel = (((colors[i].red >> (16 - visual->red_prec)) << visual->red_shift) +
			     ((colors[i].green >> (16 - visual->green_prec)) << visual->green_shift) +
			     ((colors[i].blue >> (16 - visual->blue_prec)) << visual->blue_shift));
	  success[i] = TRUE;
	}
      break;

    case GDK_VISUAL_STATIC_GRAY:
    case GDK_VISUAL_STATIC_COLOR:
      for (i=0; i<ncolors; i++)
	{
	  xcolor.red = colors[i].red;
	  xcolor.green = colors[i].green;
	  xcolor.blue = colors[i].blue;
	  xcolor.pixel = colors[i].pixel;
	  xcolor.flags = DoRed | DoGreen | DoBlue;

	  if (XAllocColor (private->xdisplay, private->xcolormap, &xcolor))
	    {
	      colors[i].pixel = xcolor.pixel;
	      success[i] = TRUE;
	    }
	  else
	    nremaining++;
	}
      break;
    }
  return nremaining;
}

gboolean
gdk_colormap_alloc_color (GdkColormap *colormap,
			  GdkColor    *color,
			  gboolean     writeable,
			  gboolean     best_match)
{
  gboolean success;

  gdk_colormap_alloc_colors (colormap, color, 1, writeable, best_match,
			     &success);

  return success;
}

gboolean
gdk_color_alloc (GdkColormap *colormap,
		 GdkColor    *color)
{
  gboolean success;

  gdk_colormap_alloc_colors (colormap, color, 1, FALSE, TRUE, &success);

  return success;
}

gboolean
gdk_color_change (GdkColormap *colormap,
		  GdkColor    *color)
{
  GdkColormapPrivate *private;
  XColor xcolor;

  g_return_val_if_fail (colormap != NULL, FALSE);
  g_return_val_if_fail (color != NULL, FALSE);

  xcolor.pixel = color->pixel;
  xcolor.red = color->red;
  xcolor.green = color->green;
  xcolor.blue = color->blue;
  xcolor.flags = DoRed | DoGreen | DoBlue;

  private = (GdkColormapPrivate*) colormap;
  XStoreColor (private->xdisplay, private->xcolormap, &xcolor);

  return TRUE;
}

guint
gdk_color_hash (const GdkColor *colora,
		const GdkColor *colorb)
{
  return ((colora->red) +
	  (colora->green << 11) +
	  (colora->blue << 22) +
	  (colora->blue >> 6));
}

gint
gdk_color_equal (const GdkColor *colora,
		 const GdkColor *colorb)
{
  g_return_val_if_fail (colora != NULL, FALSE);
  g_return_val_if_fail (colorb != NULL, FALSE);

  return ((colora->red == colorb->red) &&
	  (colora->green == colorb->green) &&
	  (colora->blue == colorb->blue));
}

/* XXX: Do not use this function until it is fixed. An X Colormap
 *      is useless unless we also have the visual.
 */
GdkColormap*
gdkx_colormap_get (Colormap xcolormap)
{
  GdkColormap *colormap;
  GdkColormapPrivate *private;

  colormap = gdk_colormap_lookup (xcolormap);
  if (colormap)
    return colormap;

  if (xcolormap == DefaultColormap (gdk_display, gdk_screen))
    return gdk_colormap_get_system ();

  private = g_new (GdkColormapPrivate, 1);
  colormap = (GdkColormap*) private;

  private->xdisplay = gdk_display;
  private->xcolormap = xcolormap;
  private->visual = NULL;
  private->private_val = TRUE;

  /* To do the following safely, we would have to have some way of finding
   * out what the size or visual of the given colormap is. It seems
   * X doesn't allow this
   */

#if 0
  for (i = 0; i < 256; i++)
    {
      xpalette[i].pixel = i;
      xpalette[i].red = 0;
      xpalette[i].green = 0;
      xpalette[i].blue = 0;
    }

  XQueryColors (gdk_display, private->xcolormap, xpalette, 256);

  for (i = 0; i < 256; i++)
    {
      colormap->colors[i].pixel = xpalette[i].pixel;
      colormap->colors[i].red = xpalette[i].red;
      colormap->colors[i].green = xpalette[i].green;
      colormap->colors[i].blue = xpalette[i].blue;
    }
#endif

  colormap->colors = NULL;
  colormap->size = 0;

  gdk_colormap_add (colormap);

  return colormap;
}


static gint
gdk_colormap_match_color (GdkColormap *cmap,
			  GdkColor    *color,
			  const gchar *available)
{
  GdkColor *colors;
  guint sum, max;
  gint rdiff, gdiff, bdiff;
  gint i, index;

  g_return_val_if_fail (cmap != NULL, 0);
  g_return_val_if_fail (color != NULL, 0);

  colors = cmap->colors;
  max = 3 * (65536);
  index = -1;

  for (i = 0; i < cmap->size; i++)
    {
      if ((!available) || (available && available[i]))
	{
	  rdiff = (color->red - colors[i].red);
	  gdiff = (color->green - colors[i].green);
	  bdiff = (color->blue - colors[i].blue);

	  sum = ABS (rdiff) + ABS (gdiff) + ABS (bdiff);

	  if (sum < max)
	    {
	      index = i;
	      max = sum;
	    }
	}
    }

  return index;
}


GdkColormap*
gdk_colormap_lookup (Colormap xcolormap)
{
  GdkColormap *cmap;

  if (!colormap_hash)
    return NULL;

  cmap = g_hash_table_lookup (colormap_hash, &xcolormap);
  return cmap;
}

static void
gdk_colormap_add (GdkColormap *cmap)
{
  GdkColormapPrivate *private;

  if (!colormap_hash)
    colormap_hash = g_hash_table_new ((GHashFunc) gdk_colormap_hash,
				      (GCompareFunc) gdk_colormap_cmp);

  private = (GdkColormapPrivate*) cmap;

  g_hash_table_insert (colormap_hash, &private->xcolormap, cmap);
}

static void
gdk_colormap_remove (GdkColormap *cmap)
{
  GdkColormapPrivate *private;

  if (!colormap_hash)
    colormap_hash = g_hash_table_new ((GHashFunc) gdk_colormap_hash,
				      (GCompareFunc) gdk_colormap_cmp);

  private = (GdkColormapPrivate*) cmap;

  g_hash_table_remove (colormap_hash, &private->xcolormap);
}

static guint
gdk_colormap_hash (Colormap *cmap)
{
  return *cmap;
}

static gint
gdk_colormap_cmp (Colormap *a,
		  Colormap *b)
{
  return (*a == *b);
}