]> Pileus Git - ~andy/gtk/blobdiff - gdk/gdkpixbuf-render.c
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[~andy/gtk] / gdk / gdkpixbuf-render.c
index 706d43b5950722271f97d46749e553d247bcbddf..23c75121b4cd1bd2077b39f55c0ebc259cbc4db9 100644 (file)
@@ -5,16 +5,16 @@
  * Author: Federico Mena-Quintero <federico@gimp.org>
  *
  * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public
+ * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Library General Public License for more details.
+ * Lesser General Public License for more details.
  *
- * You should have received a copy of the GNU Library General Public
+ * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the
  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  * Boston, MA 02111-1307, USA.
@@ -23,6 +23,7 @@
 #include <config.h>
 #include <gdk/gdk.h>
 #include "gdk-pixbuf-private.h"
+#include "gdkpixbuf.h"
 
 \f
 
@@ -34,8 +35,8 @@
  * @src_y: source Y coordinate.
  * @dest_x: Destination X coordinate.
  * @dest_y: Destination Y coordinate.
- * @width: Width of region to threshold.
- * @height: Height of region to threshold.
+ * @width: Width of region to threshold, or -1 to use pixbuf width
+ * @height: Height of region to threshold, or -1 to use pixbuf height
  * @alpha_threshold: Opacity values below this will be painted as zero; all
  * other values will be painted as one.
  *
  *
  **/
 void
-gdk_pixbuf_render_threshold_alpha (GdkPixbuf *pixbuf, GdkBitmap *bitmap,
-                                  int src_x, int src_y,
+gdk_pixbuf_render_threshold_alpha (GdkPixbuf *pixbuf,
+                                  GdkBitmap *bitmap,
+                                  int src_x,  int src_y,
                                   int dest_x, int dest_y,
-                                  int width, int height,
+                                  int width,  int height,
                                   int alpha_threshold)
 {
-       GdkGC *gc;
-       GdkColor color;
-       int x, y;
-       guchar *p;
-       int start, start_status;
-       int status;
-
-       g_return_if_fail (pixbuf != NULL);
-       g_return_if_fail (pixbuf->colorspace == GDK_COLORSPACE_RGB);
-       g_return_if_fail (pixbuf->n_channels == 3 || pixbuf->n_channels == 4);
-       g_return_if_fail (pixbuf->bits_per_sample == 8);
-
-       g_return_if_fail (bitmap != NULL);
-       g_return_if_fail (width >= 0 && height >= 0);
-       g_return_if_fail (src_x >= 0 && src_x + width <= pixbuf->width);
-       g_return_if_fail (src_y >= 0 && src_y + height <= pixbuf->height);
-
-       g_return_if_fail (alpha_threshold >= 0 && alpha_threshold <= 255);
-
-       if (width == 0 || height == 0)
-               return;
-
-       gc = gdk_gc_new (bitmap);
-
-       if (!pixbuf->has_alpha) {
-               color.pixel = (alpha_threshold == 255) ? 0 : 1;
-               gdk_gc_set_foreground (gc, &color);
-               gdk_draw_rectangle (bitmap, gc, TRUE, dest_x, dest_y, width, height);
-               gdk_gc_unref (gc);
-               return;
+  GdkGC *gc;
+  GdkColor color;
+  int x, y;
+  guchar *p;
+  int start, start_status;
+  int status;
+
+  g_return_if_fail (GDK_IS_PIXBUF (pixbuf));
+  g_return_if_fail (pixbuf->colorspace == GDK_COLORSPACE_RGB);
+  g_return_if_fail (pixbuf->n_channels == 3 || pixbuf->n_channels == 4);
+  g_return_if_fail (pixbuf->bits_per_sample == 8);
+
+  if (width == -1) 
+    width = pixbuf->width;
+  if (height == -1)
+    height = pixbuf->height;
+
+  g_return_if_fail (bitmap != NULL);
+  g_return_if_fail (width >= 0 && height >= 0);
+  g_return_if_fail (src_x >= 0 && src_x + width <= pixbuf->width);
+  g_return_if_fail (src_y >= 0 && src_y + height <= pixbuf->height);
+
+  g_return_if_fail (alpha_threshold >= 0 && alpha_threshold <= 255);
+
+  if (width == 0 || height == 0)
+    return;
+
+  gc = gdk_gc_new (bitmap);
+
+  if (!pixbuf->has_alpha)
+    {
+      color.pixel = (alpha_threshold == 255) ? 0 : 1;
+      gdk_gc_set_foreground (gc, &color);
+      gdk_draw_rectangle (bitmap, gc, TRUE, dest_x, dest_y, width, height);
+      gdk_gc_unref (gc);
+      return;
+    }
+
+  color.pixel = 0;
+  gdk_gc_set_foreground (gc, &color);
+  gdk_draw_rectangle (bitmap, gc, TRUE, dest_x, dest_y, width, height);
+
+  color.pixel = 1;
+  gdk_gc_set_foreground (gc, &color);
+
+  for (y = 0; y < height; y++)
+    {
+      p = (pixbuf->pixels + (y + src_y) * pixbuf->rowstride + src_x * pixbuf->n_channels
+          + pixbuf->n_channels - 1);
+           
+      start = 0;
+      start_status = *p < alpha_threshold;
+           
+      for (x = 0; x < width; x++)
+       {
+         status = *p < alpha_threshold;
+         
+         if (status != start_status)
+           {
+             if (!start_status)
+               gdk_draw_line (bitmap, gc,
+                              start + dest_x, y + dest_y,
+                              x - 1 + dest_x, y + dest_y);
+             
+             start = x;
+             start_status = status;
+           }
+         
+         p += pixbuf->n_channels;
        }
-
-       color.pixel = 0;
-       gdk_gc_set_foreground (gc, &color);
-       gdk_draw_rectangle (bitmap, gc, TRUE, dest_x, dest_y, width, height);
-
-       color.pixel = 1;
-       gdk_gc_set_foreground (gc, &color);
-
-       for (y = 0; y < height; y++) {
-               p = (pixbuf->pixels + (y + src_y) * pixbuf->rowstride + src_x * pixbuf->n_channels
-                    + pixbuf->n_channels - 1);
-
-               start = 0;
-               start_status = *p < alpha_threshold;
-
-               for (x = 0; x < width; x++) {
-                       status = *p < alpha_threshold;
-
-                       if (status != start_status) {
-                               if (!start_status)
-                                       gdk_draw_line (bitmap, gc,
-                                                      start + dest_x, y + dest_y,
-                                                      x - 1 + dest_x, y + dest_y);
-
-                               start = x;
-                               start_status = status;
-                       }
-
-                       p += pixbuf->n_channels;
-               }
-
-               if (!start_status)
-                       gdk_draw_line (bitmap, gc,
-                                      start + dest_x, y + dest_y,
-                                      x - 1 + dest_x, y + dest_y);
-       }
-
-       gdk_gc_unref (gc);
+      
+      if (!start_status)
+       gdk_draw_line (bitmap, gc,
+                      start + dest_x, y + dest_y,
+                      x - 1 + dest_x, y + dest_y);
+    }
+       
+  gdk_gc_unref (gc);
 }
 
 \f
 
-/* Creates a buffer by stripping the alpha channel of a pixbuf */
-static guchar *
-remove_alpha (GdkPixbuf *pixbuf, int x, int y, int width, int height, int *rowstride)
-{
-       guchar *buf;
-       int xx, yy;
-       guchar *src, *dest;
-
-       g_assert (pixbuf->n_channels == 4);
-       g_assert (pixbuf->has_alpha);
-       g_assert (width > 0 && height > 0);
-       g_assert (x >= 0 && x + width <= pixbuf->width);
-       g_assert (y >= 0 && y + height <= pixbuf->height);
-
-       *rowstride = 4 * ((width * 3 + 3) / 4);
-
-       buf = g_new (guchar, *rowstride * height);
-
-       for (yy = 0; yy < height; yy++) {
-               src = pixbuf->pixels + pixbuf->rowstride * (yy + y) + x * pixbuf->n_channels;
-               dest = buf + *rowstride * yy;
-
-               for (xx = 0; xx < width; xx++) {
-                       *dest++ = *src++;
-                       *dest++ = *src++;
-                       *dest++ = *src++;
-                       src++;
-               }
-       }
-
-       return buf;
-}
-
 /**
  * gdk_pixbuf_render_to_drawable:
  * @pixbuf: A pixbuf.
@@ -166,8 +144,8 @@ remove_alpha (GdkPixbuf *pixbuf, int x, int y, int width, int height, int *rowst
  * @src_y: Source Y coordinate within pixbuf.
  * @dest_x: Destination X coordinate within drawable.
  * @dest_y: Destination Y coordinate within drawable.
- * @width: Width of region to render, in pixels.
- * @height: Height of region to render, in pixels.
+ * @width: Width of region to render, in pixels, or -1 to use pixbuf width
+ * @height: Height of region to render, in pixels, or -1 to use pixbuf height
  * @dither: Dithering mode for GdkRGB.
  * @x_dither: X offset for dither.
  * @y_dither: Y offset for dither.
@@ -186,53 +164,65 @@ remove_alpha (GdkPixbuf *pixbuf, int x, int y, int width, int height, int *rowst
  * dither offsets can be both zero.
  **/
 void
-gdk_pixbuf_render_to_drawable (GdkPixbuf *pixbuf,
-                              GdkDrawable *drawable, GdkGC *gc,
-                              int src_x, int src_y,
-                              int dest_x, int dest_y,
-                              int width, int height,
+gdk_pixbuf_render_to_drawable (GdkPixbuf   *pixbuf,
+                              GdkDrawable *drawable,
+                              GdkGC       *gc,
+                              int src_x,    int src_y,
+                              int dest_x,   int dest_y,
+                              int width,    int height,
                               GdkRgbDither dither,
                               int x_dither, int y_dither)
 {
-       guchar *buf;
-       int rowstride;
-
-       g_return_if_fail (pixbuf != NULL);
-       g_return_if_fail (pixbuf->colorspace == GDK_COLORSPACE_RGB);
-       g_return_if_fail (pixbuf->n_channels == 3 || pixbuf->n_channels == 4);
-       g_return_if_fail (pixbuf->bits_per_sample == 8);
-
-       g_return_if_fail (drawable != NULL);
-       g_return_if_fail (gc != NULL);
-
-       g_return_if_fail (width >= 0 && height >= 0);
-       g_return_if_fail (src_x >= 0 && src_x + width <= pixbuf->width);
-       g_return_if_fail (src_y >= 0 && src_y + height <= pixbuf->height);
-
-       if (width == 0 || height == 0)
-               return;
-
-       /* This will have to be modified once we support other image types.
-        * Also, GdkRGB does not have gdk_draw_rgb_32_image_dithalign(), so we
-        * have to pack the buffer first.  Sigh.
-        */
-
-       if (pixbuf->has_alpha)
-               buf = remove_alpha (pixbuf, src_x, src_y, width, height, &rowstride);
-       else {
-               buf = pixbuf->pixels + src_y * pixbuf->rowstride + src_x * 3;
-               rowstride = pixbuf->rowstride;
-       }
+  int rowstride;
+  guchar *buf;
+
+  g_return_if_fail (GDK_IS_PIXBUF (pixbuf));
+  g_return_if_fail (pixbuf->colorspace == GDK_COLORSPACE_RGB);
+  g_return_if_fail (pixbuf->n_channels == 3 || pixbuf->n_channels == 4);
+  g_return_if_fail (pixbuf->bits_per_sample == 8);
+
+  g_return_if_fail (drawable != NULL);
+  g_return_if_fail (gc != NULL);
+
+  if (width == -1) 
+    width = pixbuf->width;
+  if (height == -1)
+    height = pixbuf->height;
 
-       gdk_draw_rgb_image_dithalign (drawable, gc,
-                                     dest_x, dest_y,
-                                     width, height,
-                                     dither,
-                                     buf, rowstride,
-                                     x_dither, y_dither);
+  g_return_if_fail (width >= 0 && height >= 0);
+  g_return_if_fail (src_x >= 0 && src_x + width <= pixbuf->width);
+  g_return_if_fail (src_y >= 0 && src_y + height <= pixbuf->height);
 
-       if (pixbuf->has_alpha)
-               g_free (buf);
+  if (width == 0 || height == 0)
+    return;
+
+  /* This will have to be modified once we support other image types.
+   */
+
+  if (pixbuf->n_channels == 4)
+    {
+      buf = pixbuf->pixels + src_y * pixbuf->rowstride + src_x * 4;
+      rowstride = pixbuf->rowstride;
+
+      gdk_draw_rgb_32_image_dithalign (drawable, gc,
+                                      dest_x, dest_y,
+                                      width, height,
+                                      dither,
+                                      buf, rowstride,
+                                      x_dither, y_dither);
+    }
+  else                         /* n_channels == 3 */
+    {
+      buf = pixbuf->pixels + src_y * pixbuf->rowstride + src_x * 3;
+      rowstride = pixbuf->rowstride;
+
+      gdk_draw_rgb_image_dithalign (drawable, gc,
+                                   dest_x, dest_y,
+                                   width, height,
+                                   dither,
+                                   buf, rowstride,
+                                   x_dither, y_dither);
+    }
 }
 
 \f
@@ -245,8 +235,8 @@ gdk_pixbuf_render_to_drawable (GdkPixbuf *pixbuf,
  * @src_y: Source Y coordinates within pixbuf.
  * @dest_x: Destination X coordinate within drawable.
  * @dest_y: Destination Y coordinate within drawable.
- * @width: Width of region to render, in pixels.
- * @height: Height of region to render, in pixels.
+ * @width: Width of region to render, in pixels, or -1 to use pixbuf width.
+ * @height: Height of region to render, in pixels, or -1 to use pixbuf height.
  * @alpha_mode: If the image does not have opacity information, this is ignored.
  * Otherwise, specifies how to handle transparency when rendering.
  * @alpha_threshold: If the image does have opacity information and @alpha_mode
@@ -266,62 +256,182 @@ gdk_pixbuf_render_to_drawable (GdkPixbuf *pixbuf,
  * the alpha channel of the image.  If performance is crucial, consider handling
  * the alpha channel yourself (possibly by caching it in your application) and
  * using gdk_pixbuf_render_to_drawable() or GdkRGB directly instead.
+ *
+ * The #GDK_PIXBUF_ALPHA_FULL mode involves round trips to the X
+ * server, and may also be somewhat slow in its current implementation
+ * (though in the future it could be made significantly faster, in
+ * principle).
  **/
 void
-gdk_pixbuf_render_to_drawable_alpha (GdkPixbuf *pixbuf, GdkDrawable *drawable,
-                                    int src_x, int src_y,
-                                    int dest_x, int dest_y,
-                                    int width, int height,
+gdk_pixbuf_render_to_drawable_alpha (GdkPixbuf   *pixbuf,
+                                    GdkDrawable *drawable,
+                                    int src_x,    int src_y,
+                                    int dest_x,   int dest_y,
+                                    int width,    int height,
                                     GdkPixbufAlphaMode alpha_mode,
-                                    int alpha_threshold,
-                                    GdkRgbDither dither,
+                                    int                alpha_threshold,
+                                    GdkRgbDither       dither,
                                     int x_dither, int y_dither)
 {
-       GdkBitmap *bitmap = NULL;
-       GdkGC *gc;
-
-       g_return_if_fail (pixbuf != NULL);
-       g_return_if_fail (pixbuf->colorspace == GDK_COLORSPACE_RGB);
-       g_return_if_fail (pixbuf->n_channels == 3 || pixbuf->n_channels == 4);
-       g_return_if_fail (pixbuf->bits_per_sample == 8);
-
-       g_return_if_fail (drawable != NULL);
-       g_return_if_fail (width >= 0 && height >= 0);
-       g_return_if_fail (src_x >= 0 && src_x + width <= pixbuf->width);
-       g_return_if_fail (src_y >= 0 && src_y + height <= pixbuf->height);
-
-       if (width == 0 || height == 0)
-               return;
-
-       gc = gdk_gc_new (drawable);
-
-       if (pixbuf->has_alpha) {
-               /* Right now we only support GDK_PIXBUF_ALPHA_BILEVEL, so we
-                * unconditionally create the clipping mask.
-                */
-
-               bitmap = gdk_pixmap_new (NULL, width, height, 1);
-               gdk_pixbuf_render_threshold_alpha (pixbuf, bitmap,
-                                                  src_x, src_y,
-                                                  0, 0,
-                                                  width, height,
-                                                  alpha_threshold);
-
-               gdk_gc_set_clip_mask (gc, bitmap);
-               gdk_gc_set_clip_origin (gc, dest_x, dest_y);
-       }
-
-       gdk_pixbuf_render_to_drawable (pixbuf, drawable, gc,
-                                      src_x, src_y,
-                                      dest_x, dest_y,
-                                      width, height,
-                                      dither,
-                                      x_dither, y_dither);
-
-       if (bitmap)
-               gdk_bitmap_unref (bitmap);
-
-       gdk_gc_unref (gc);
+  GdkBitmap *bitmap = NULL;
+  GdkGC *gc;
+  GdkPixbuf *composited = NULL;
+  gint dwidth, dheight;
+  GdkRegion *clip;
+  GdkRegion *drect;
+  GdkRectangle tmp_rect;
+  
+  g_return_if_fail (GDK_IS_PIXBUF (pixbuf));
+  g_return_if_fail (pixbuf->colorspace == GDK_COLORSPACE_RGB);
+  g_return_if_fail (pixbuf->n_channels == 3 || pixbuf->n_channels == 4);
+  g_return_if_fail (pixbuf->bits_per_sample == 8);
+
+  g_return_if_fail (drawable != NULL);
+
+  if (width == -1) 
+    width = pixbuf->width;
+  if (height == -1)
+    height = pixbuf->height;
+
+  g_return_if_fail (width >= 0 && height >= 0);
+  g_return_if_fail (src_x >= 0 && src_x + width <= pixbuf->width);
+  g_return_if_fail (src_y >= 0 && src_y + height <= pixbuf->height);
+
+  /* Clip to the drawable; this is required for get_from_drawable() so
+   * can't be done implicitly
+   */
+  
+  if (dest_x < 0)
+    {
+      src_x -= dest_x;
+      width += dest_x;
+      dest_x = 0;
+    }
+
+  if (dest_y < 0)
+    {
+      src_y -= dest_y;
+      height += dest_y;
+      dest_y = 0;
+    }
+
+  gdk_drawable_get_size (drawable, &dwidth, &dheight);
+
+  if ((dest_x + width) > dwidth)
+    width = dwidth - dest_x;
+
+  if ((dest_y + height) > dheight)
+    height = dheight - dest_y;
+
+  if (width <= 0 || height <= 0)
+    return;
+
+  /* Clip to the clip region; this avoids getting more
+   * image data from the server than we need to.
+   */
+  
+  tmp_rect.x = dest_x;
+  tmp_rect.y = dest_y;
+  tmp_rect.width = width;
+  tmp_rect.height = height;
+
+  drect = gdk_region_rectangle (&tmp_rect);
+  clip = gdk_drawable_get_clip_region (drawable);
+
+  gdk_region_intersect (drect, clip);
+
+  gdk_region_get_clipbox (drect, &tmp_rect);
+  
+  gdk_region_destroy (drect);
+  gdk_region_destroy (clip);
+
+  if (tmp_rect.width == 0 ||
+      tmp_rect.height == 0)
+    return;
+  
+  /* Actually draw */
+  
+  gc = gdk_gc_new (drawable);
+
+  if (pixbuf->has_alpha)
+    {
+      if (alpha_mode == GDK_PIXBUF_ALPHA_FULL)
+        {
+          GdkPixbuf *sub = NULL;
+          
+          composited = gdk_pixbuf_get_from_drawable (NULL,
+                                                     drawable,
+                                                     NULL,
+                                                     dest_x, dest_y,
+                                                     0, 0,
+                                                     width, height);
+
+          if (composited)
+            {
+              if (src_x != 0 || src_y != 0)
+                {
+                  sub = gdk_pixbuf_new_subpixbuf (pixbuf, src_x, src_y,
+                                                  width, height);
+                }
+              
+              gdk_pixbuf_composite (sub ? sub : pixbuf,
+                                    composited,
+                                    0, 0,
+                                    width, height,
+                                    0, 0,
+                                    1.0, 1.0,
+                                    GDK_INTERP_BILINEAR,
+                                    255);
+              
+              if (sub)
+                g_object_unref (G_OBJECT (sub));
+            }
+          else
+            alpha_mode = GDK_PIXBUF_ALPHA_BILEVEL; /* fall back */
+        }
+
+      if (alpha_mode == GDK_PIXBUF_ALPHA_BILEVEL)
+        {
+          bitmap = gdk_pixmap_new (NULL, width, height, 1);
+          gdk_pixbuf_render_threshold_alpha (pixbuf, bitmap,
+                                             src_x, src_y,
+                                             0, 0,
+                                             width, height,
+                                             alpha_threshold);
+          
+          gdk_gc_set_clip_mask (gc, bitmap);
+          gdk_gc_set_clip_origin (gc, dest_x, dest_y);
+        }
+    }
+
+  if (composited)
+    {
+      gdk_pixbuf_render_to_drawable (composited,
+                                     drawable, gc,
+                                     0, 0,
+                                     dest_x, dest_y,
+                                     width, height,
+                                     dither,
+                                     x_dither, y_dither);
+    }
+  else
+    {
+      gdk_pixbuf_render_to_drawable (pixbuf,
+                                     drawable, gc,
+                                     src_x, src_y,
+                                     dest_x, dest_y,
+                                     width, height,
+                                     dither,
+                                     x_dither, y_dither);
+    }
+
+  if (bitmap)
+    gdk_bitmap_unref (bitmap);
+
+  if (composited)
+    g_object_unref (G_OBJECT (composited));
+
+  gdk_gc_unref (gc);
 }
 
 /**
@@ -333,43 +443,93 @@ gdk_pixbuf_render_to_drawable_alpha (GdkPixbuf *pixbuf, GdkDrawable *drawable,
  *
  * Creates a pixmap and a mask bitmap which are returned in the @pixmap_return
  * and @mask_return arguments, respectively, and renders a pixbuf and its
- * corresponding tresholded alpha mask to them.  This is merely a convenience
+ * corresponding thresholded alpha mask to them.  This is merely a convenience
  * function; applications that need to render pixbufs with dither offsets or to
  * given drawables should use gdk_pixbuf_render_to_drawable_alpha() or
  * gdk_pixbuf_render_to_drawable(), and gdk_pixbuf_render_threshold_alpha().
  *
+ * The pixmap that is created is created for the colormap returned
+ * by gdk_rgb_get_colormap(). You normally will want to instead use
+ * the actual colormap for a widget, and use
+ * gdk_pixbuf_render_pixmap_and_mask_for_colormap.
+ *
  * If the pixbuf does not have an alpha channel, then *@mask_return will be set
  * to NULL.
  **/
 void
-gdk_pixbuf_render_pixmap_and_mask (GdkPixbuf *pixbuf,
-                                  GdkPixmap **pixmap_return, GdkBitmap **mask_return,
-                                  int alpha_threshold)
+gdk_pixbuf_render_pixmap_and_mask (GdkPixbuf  *pixbuf,
+                                  GdkPixmap **pixmap_return,
+                                  GdkBitmap **mask_return,
+                                  int         alpha_threshold)
 {
-        g_return_if_fail (pixbuf != NULL);
-
-       if (pixmap_return) {
-               GdkGC *gc;
-
-               *pixmap_return = gdk_pixmap_new (NULL, pixbuf->width, pixbuf->height,
-                                                gdk_rgb_get_visual ()->depth);
-               gc = gdk_gc_new (*pixmap_return);
-               gdk_pixbuf_render_to_drawable (pixbuf, *pixmap_return, gc,
-                                              0, 0, 0, 0,
-                                              pixbuf->width, pixbuf->height,
-                                              GDK_RGB_DITHER_NORMAL,
-                                              0, 0);
-               gdk_gc_unref (gc);
-       }
+  gdk_pixbuf_render_pixmap_and_mask_for_colormap (pixbuf,
+                                                 gdk_rgb_get_colormap (),
+                                                 pixmap_return, mask_return,
+                                                 alpha_threshold);
+}
 
-       if (mask_return) {
-               if (pixbuf->has_alpha) {
-                       *mask_return = gdk_pixmap_new (NULL, pixbuf->width, pixbuf->height, 1);
-                       gdk_pixbuf_render_threshold_alpha (pixbuf, *mask_return,
-                                                          0, 0, 0, 0,
-                                                          pixbuf->width, pixbuf->height,
-                                                          alpha_threshold);
-               } else
-                       *mask_return = NULL;
+/**
+ * gdk_pixbuf_render_pixmap_and_mask_for_colormap:
+ * @pixbuf: A pixbuf.
+ * @colormap: A #GdkColormap
+ * @pixmap_return: Return value for the created pixmap.
+ * @mask_return: Return value for the created mask.
+ * @alpha_threshold: Threshold value for opacity values.
+ *
+ * Creates a pixmap and a mask bitmap which are returned in the @pixmap_return
+ * and @mask_return arguments, respectively, and renders a pixbuf and its
+ * corresponding tresholded alpha mask to them.  This is merely a convenience
+ * function; applications that need to render pixbufs with dither offsets or to
+ * given drawables should use gdk_pixbuf_render_to_drawable_alpha() or
+ * gdk_pixbuf_render_to_drawable(), and gdk_pixbuf_render_threshold_alpha().
+ *
+ * The pixmap that is created uses the #GdkColormap specified by @colormap.
+ * This colormap must match the colormap of the window where the pixmap
+ * will eventually be used or an error will result.
+ *
+ * If the pixbuf does not have an alpha channel, then *@mask_return will be set
+ * to NULL.
+ **/
+void
+gdk_pixbuf_render_pixmap_and_mask_for_colormap (GdkPixbuf   *pixbuf,
+                                               GdkColormap *colormap,
+                                               GdkPixmap  **pixmap_return,
+                                               GdkBitmap  **mask_return,
+                                               int          alpha_threshold)
+{
+  g_return_if_fail (pixbuf != NULL);
+  
+  if (pixmap_return)
+    {
+      GdkGC *gc;
+      
+      *pixmap_return = gdk_pixmap_new (NULL, gdk_pixbuf_get_width (pixbuf), gdk_pixbuf_get_height (pixbuf),
+                                      gdk_colormap_get_visual (colormap)->depth);
+      gdk_drawable_set_colormap (GDK_DRAWABLE (*pixmap_return),
+                                 colormap);
+      gc = gdk_gc_new (*pixmap_return);
+      gdk_pixbuf_render_to_drawable (pixbuf, *pixmap_return, gc,
+                                    0, 0, 0, 0,
+                                    gdk_pixbuf_get_width (pixbuf), gdk_pixbuf_get_height (pixbuf),
+                                    GDK_RGB_DITHER_NORMAL,
+                                    0, 0);
+      gdk_gc_unref (gc);
+    }
+  
+  if (mask_return)
+    {
+      if (gdk_pixbuf_get_has_alpha (pixbuf))
+       {
+         *mask_return = gdk_pixmap_new (NULL, gdk_pixbuf_get_width (pixbuf), gdk_pixbuf_get_height (pixbuf), 1);
+          
+         gdk_pixbuf_render_threshold_alpha (pixbuf, *mask_return,
+                                            0, 0, 0, 0,
+                                            gdk_pixbuf_get_width (pixbuf), gdk_pixbuf_get_height (pixbuf),
+                                            alpha_threshold);
        }
+      else
+       *mask_return = NULL;
+    }
 }
+
+