gtk/gdk/gdkpixbuf-render.c
Owen Taylor a3914aaf10 Deprecate gdk_set/get_use_xshm, make gdk_set_use_xshm a noop. Remove
Fri Sep  7 18:17:47 2001  Owen Taylor  <otaylor@redhat.com>

	* gdk/gdk.h gdk/x11/gdkmain-x11.c: Deprecate gdk_set/get_use_xshm,
	make gdk_set_use_xshm a noop. Remove --no-xshm command line
	option. If we aren't autodetecting properly, we need
	to fix the problem, or at least make it an environment
	variable setting, to avoid problems with propagating
	to embedded children, plugins, etc.

	* gdk/gdkcolor.h: Deprecate gdk_colormap_get_system_size().

	* gdk/gdkpixbuf-render.c gdk/gdkpixbuf.h
	(gdk_pixbuf_render_pixmap_and_mask_for_colormap):
	New function to render a pixmap and mask for a particular colormap.

	* gtk/gtkwindow.c (get_pixmap_and_mask): Change to use
	gdk_pixbuf_render_pixmap_and_mask_for_colormap () instead
	of internal implementation of the same.
2001-09-07 22:33:09 +00:00

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/* GdkPixbuf library - Rendering functions
*
* Copyright (C) 1999 The Free Software Foundation
*
* 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 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
* Lesser General Public License for more details.
*
* 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.
*/
#include <config.h>
#include <gdk/gdk.h>
#include "gdk-pixbuf-private.h"
#include "gdkpixbuf.h"
/**
* gdk_pixbuf_render_threshold_alpha:
* @pixbuf: A pixbuf.
* @bitmap: Bitmap where the bilevel mask will be painted to.
* @src_x: Source X coordinate.
* @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.
* @alpha_threshold: Opacity values below this will be painted as zero; all
* other values will be painted as one.
*
* Takes the opacity values in a rectangular portion of a pixbuf and thresholds
* them to produce a bi-level alpha mask that can be used as a clipping mask for
* a drawable.
*
**/
void
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 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;
}
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);
}
/**
* gdk_pixbuf_render_to_drawable:
* @pixbuf: A pixbuf.
* @drawable: Destination drawable.
* @gc: GC used for rendering.
* @src_x: Source X coordinate within pixbuf.
* @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.
* @dither: Dithering mode for GdkRGB.
* @x_dither: X offset for dither.
* @y_dither: Y offset for dither.
*
* Renders a rectangular portion of a pixbuf to a drawable while using the
* specified GC. This is done using GdkRGB, so the specified drawable must have
* the GdkRGB visual and colormap. Note that this function will ignore the
* opacity information for images with an alpha channel; the GC must already
* have the clipping mask set if you want transparent regions to show through.
*
* For an explanation of dither offsets, see the GdkRGB documentation. In
* brief, the dither offset is important when re-rendering partial regions of an
* image to a rendered version of the full image, or for when the offsets to a
* base position change, as in scrolling. The dither matrix has to be shifted
* for consistent visual results. If you do not have any of these cases, the
* 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,
GdkRgbDither dither,
int x_dither, int y_dither)
{
int rowstride;
guchar *buf;
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.
*/
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);
}
}
/**
* gdk_pixbuf_render_to_drawable_alpha:
* @pixbuf: A pixbuf.
* @drawable: Destination drawable.
* @src_x: Source X coordinate within 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.
* @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
* is GDK_PIXBUF_ALPHA_BILEVEL, specifies the threshold value for opacity
* values.
* @dither: Dithering mode for GdkRGB.
* @x_dither: X offset for dither.
* @y_dither: Y offset for dither.
*
* Renders a rectangular portion of a pixbuf to a drawable. This is done using
* GdkRGB, so the specified drawable must have the GdkRGB visual and colormap.
*
* When used with #GDK_PIXBUF_ALPHA_BILEVEL, this function has to create a bitmap
* out of the thresholded alpha channel of the image and, it has to set this
* bitmap as the clipping mask for the GC used for drawing. This can be a
* significant performance penalty depending on the size and the complexity of
* 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,
GdkPixbufAlphaMode alpha_mode,
int alpha_threshold,
GdkRgbDither dither,
int x_dither, int y_dither)
{
GdkBitmap *bitmap = NULL;
GdkGC *gc;
GdkPixbuf *composited = NULL;
gint dwidth, dheight;
GdkRegion *clip;
GdkRegion *drect;
GdkRectangle tmp_rect;
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);
/* 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);
}
/**
* gdk_pixbuf_render_pixmap_and_mask:
* @pixbuf: A pixbuf.
* @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 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_for_colormap (pixbuf,
gdk_rgb_get_colormap (),
pixmap_return, mask_return,
alpha_threshold);
}
/**
* 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;
}
}