forked from AuroraMiddleware/gtk
351 lines
12 KiB
C
351 lines
12 KiB
C
/* 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/gdk-pixbuf.h>
|
||
#include "gdkpixbuf.h"
|
||
#include "gdkscreen.h"
|
||
#include "gdkinternals.h"
|
||
#include "gdkalias.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, 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.
|
||
*
|
||
* 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 (gdk_pixbuf_get_colorspace (pixbuf) == GDK_COLORSPACE_RGB);
|
||
g_return_if_fail (gdk_pixbuf_get_n_channels (pixbuf) == 3 ||
|
||
gdk_pixbuf_get_n_channels (pixbuf) == 4);
|
||
g_return_if_fail (gdk_pixbuf_get_bits_per_sample (pixbuf) == 8);
|
||
|
||
if (width == -1)
|
||
width = gdk_pixbuf_get_width (pixbuf);
|
||
if (height == -1)
|
||
height = gdk_pixbuf_get_height (pixbuf);
|
||
|
||
g_return_if_fail (bitmap != NULL);
|
||
g_return_if_fail (width >= 0 && height >= 0);
|
||
g_return_if_fail (src_x >= 0 && src_x + width <= gdk_pixbuf_get_width (pixbuf));
|
||
g_return_if_fail (src_y >= 0 && src_y + height <= gdk_pixbuf_get_height (pixbuf));
|
||
|
||
g_return_if_fail (alpha_threshold >= 0 && alpha_threshold <= 255);
|
||
|
||
if (width == 0 || height == 0)
|
||
return;
|
||
|
||
gc = _gdk_drawable_get_scratch_gc (bitmap, FALSE);
|
||
|
||
if (!gdk_pixbuf_get_has_alpha (pixbuf))
|
||
{
|
||
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);
|
||
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 = (gdk_pixbuf_get_pixels (pixbuf) + (y + src_y) * gdk_pixbuf_get_rowstride (pixbuf) + src_x * gdk_pixbuf_get_n_channels (pixbuf)
|
||
+ gdk_pixbuf_get_n_channels (pixbuf) - 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 += gdk_pixbuf_get_n_channels (pixbuf);
|
||
}
|
||
|
||
if (!start_status)
|
||
gdk_draw_line (bitmap, gc,
|
||
start + dest_x, y + dest_y,
|
||
x - 1 + dest_x, y + dest_y);
|
||
}
|
||
}
|
||
|
||
|
||
|
||
/**
|
||
* 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, 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.
|
||
*
|
||
* 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.
|
||
*
|
||
* Deprecated: 2.4: This function is obsolete. Use gdk_draw_pixbuf() instead.
|
||
**/
|
||
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)
|
||
{
|
||
gdk_draw_pixbuf (drawable, gc, pixbuf,
|
||
src_x, src_y, dest_x, dest_y, width, height,
|
||
dither, 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, or -1 to use pixbuf width.
|
||
* @height: Height of region to render, in pixels, or -1 to use pixbuf height.
|
||
* @alpha_mode: Ignored. Present for backwards compatibility.
|
||
* @alpha_threshold: Ignored. Present for backwards compatibility
|
||
* @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. The destination
|
||
* drawable must have a colormap. All windows have a colormap, however, pixmaps
|
||
* only have colormap by default if they were created with a non-%NULL window argument.
|
||
* Otherwise a colormap must be set on them with gdk_drawable_set_colormap.
|
||
*
|
||
* On older X servers, rendering pixbufs with an alpha channel involves round trips
|
||
* to the X server, and may be somewhat slow.
|
||
*
|
||
* Deprecated: 2.4: This function is obsolete. Use gdk_draw_pixbuf() instead.
|
||
**/
|
||
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)
|
||
{
|
||
gdk_draw_pixbuf (drawable, NULL, pixbuf,
|
||
src_x, src_y, dest_x, dest_y, width, height,
|
||
dither, x_dither, y_dither);
|
||
}
|
||
|
||
/**
|
||
* gdk_pixbuf_render_pixmap_and_mask:
|
||
* @pixbuf: A pixbuf.
|
||
* @pixmap_return: Location to store a pointer to the created pixmap,
|
||
* or %NULL if the pixmap is not needed.
|
||
* @mask_return: Location to store a pointer to the created mask,
|
||
* or %NULL if the mask is not needed.
|
||
* @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_draw_pixbuf() 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: Location to store a pointer to the created pixmap,
|
||
* or %NULL if the pixmap is not needed.
|
||
* @mask_return: Location to store a pointer to the created mask,
|
||
* or %NULL if the mask is not needed.
|
||
* @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_draw_pixbuf(), 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)
|
||
{
|
||
GdkScreen *screen;
|
||
|
||
g_return_if_fail (GDK_IS_PIXBUF (pixbuf));
|
||
g_return_if_fail (GDK_IS_COLORMAP (colormap));
|
||
|
||
screen = gdk_colormap_get_screen (colormap);
|
||
|
||
if (pixmap_return)
|
||
{
|
||
GdkGC *gc;
|
||
*pixmap_return = gdk_pixmap_new (gdk_screen_get_root_window (screen),
|
||
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_drawable_get_scratch_gc (*pixmap_return, FALSE);
|
||
|
||
/* If the pixbuf has an alpha channel, using gdk_pixbuf_draw would give
|
||
* random pixel values in the area that are within the mask, but semi-
|
||
* transparent. So we treat the pixbuf like a pixbuf without alpha channel;
|
||
* see bug #487865.
|
||
*/
|
||
if (gdk_pixbuf_get_has_alpha (pixbuf))
|
||
gdk_draw_rgb_32_image (*pixmap_return, gc,
|
||
0, 0,
|
||
gdk_pixbuf_get_width (pixbuf), gdk_pixbuf_get_height (pixbuf),
|
||
GDK_RGB_DITHER_NORMAL,
|
||
gdk_pixbuf_get_pixels (pixbuf), gdk_pixbuf_get_rowstride (pixbuf));
|
||
else
|
||
gdk_draw_pixbuf (*pixmap_return, gc, pixbuf,
|
||
0, 0, 0, 0,
|
||
gdk_pixbuf_get_width (pixbuf), gdk_pixbuf_get_height (pixbuf),
|
||
GDK_RGB_DITHER_NORMAL,
|
||
0, 0);
|
||
}
|
||
|
||
if (mask_return)
|
||
{
|
||
if (gdk_pixbuf_get_has_alpha (pixbuf))
|
||
{
|
||
*mask_return = gdk_pixmap_new (gdk_screen_get_root_window (screen),
|
||
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;
|
||
}
|
||
}
|
||
|
||
#define __GDK_PIXBUF_RENDER_C__
|
||
#include "gdkaliasdef.c"
|
||
|