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<!-- ##### SECTION Title ##### -->
Rendering
<!-- ##### SECTION Short_Description ##### -->
Rendering a pixbuf to a GDK drawable.
<!-- ##### SECTION Long_Description ##### -->
<para>
The GdkPixbuf library provides several convenience functions to
render pixbufs to GDK drawables. It uses the GdkRGB to render the
image data.
</para>
<para>
At this point there is not a standard alpha channel extension for
the X Window System, so it is not possible to use full opacity
information when painting images to arbitrary drawables. The
GdkPixbuf convenience functions will threshold the opacity
information to create a bi-level clipping mask (black and white),
and use that to draw the image onto a drawable.
</para>
<important>
<para>
Since these functions use GdkRGB for rendering, you must
initialize GdkRGB before using any of them. You can do this by
calling gdk_rgb_init() near the beginning of your program.
</para>
</important>
<!-- ##### SECTION See_Also ##### -->
<para>
GdkRGB
</para>
<!-- ##### ENUM GdkPixbufAlphaMode ##### -->
<para>
These values can be passed to
gdk_pixbuf_render_to_drawable_alpha() to control how the alpha
chanel of an image should be handled. This function can create a
bilevel clipping mask (black and white) and use it while painting
the image. In the future, when the X Window System gets an alpha
channel extension, it will be possible to do full alpha
compositing onto arbitrary drawables. For now both cases fall
back to a bilevel clipping mask.
</para>
@GDK_PIXBUF_ALPHA_BILEVEL: A bilevel clipping mask (black and white)
will be created and used to draw the image. Pixels below 0.5 opacity
will be considered fully transparent, and all others will be
considered fully opaque.
@GDK_PIXBUF_ALPHA_FULL: For now falls back to #GDK_PIXBUF_ALPHA_BILEVEL.
In the future it will do full alpha compositing.
<!-- ##### FUNCTION gdk_pixbuf_render_to_drawable_alpha ##### -->
<para>
</para>
@pixbuf:
@drawable:
@src_x:
@src_y:
@dest_x:
@dest_y:
@width:
@height:
@alpha_mode:
@alpha_threshold:
@dither:
@x_dither:
@y_dither:
<!-- ##### FUNCTION gdk_pixbuf_render_to_drawable ##### -->
<para>
</para>
@pixbuf:
@drawable:
@gc:
@src_x:
@src_y:
@dest_x:
@dest_y:
@width:
@height:
@dither:
@x_dither:
@y_dither:
<!-- ##### FUNCTION gdk_pixbuf_render_threshold_alpha ##### -->
<para>
</para>
@pixbuf:
@bitmap:
@src_x:
@src_y:
@dest_x:
@dest_y:
@width:
@height:
@alpha_threshold: <!--
Local variables:
mode: sgml
sgml-parent-document: ("../gdk-pixbuf.sgml" "book" "refsect2" "")
End:
-->
<!-- ##### FUNCTION gdk_pixbuf_render_pixmap_and_mask ##### -->
<para>
</para>
@pixbuf:
@pixmap_return:
@mask_return:
@alpha_threshold:
|
