1999-11-04 07:30:04 +00:00
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<!-- ##### SECTION Title ##### -->
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1999-11-04 21:52:08 +00:00
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Rendering
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1999-11-04 07:30:04 +00:00
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<!-- ##### SECTION Short_Description ##### -->
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1999-12-08 21:17:53 +00:00
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Rendering a pixbuf to a GDK drawable.
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1999-11-04 07:30:04 +00:00
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<!-- ##### SECTION Long_Description ##### -->
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1999-11-04 21:52:08 +00:00
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<para>
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2000-04-13 01:18:41 +00:00
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The <application>gdk-pixbuf</application> library provides several
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convenience functions to render pixbufs to GDK drawables. It uses
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the GdkRGB to render the image data.
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1999-11-04 21:52:08 +00:00
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</para>
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<para>
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At this point there is not a standard alpha channel extension for
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the X Window System, so it is not possible to use full opacity
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information when painting images to arbitrary drawables. The
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2000-04-13 01:18:41 +00:00
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<application>gdk-pixbuf</application> convenience functions will
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threshold the opacity information to create a bi-level clipping
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mask (black and white), and use that to draw the image onto a
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drawable.
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1999-11-04 21:52:08 +00:00
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</para>
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1999-11-04 07:30:04 +00:00
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1999-12-17 01:21:28 +00:00
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<important>
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<para>
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Since these functions use GdkRGB for rendering, you must
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2000-02-01 00:42:39 +00:00
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initialize GdkRGB before using any of them. You can do this by
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calling gdk_rgb_init() near the beginning of your program.
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1999-12-17 01:21:28 +00:00
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</para>
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</important>
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1999-11-04 07:30:04 +00:00
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<!-- ##### SECTION See_Also ##### -->
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1999-11-04 21:52:08 +00:00
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<para>
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GdkRGB
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</para>
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1999-11-04 07:30:04 +00:00
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<!-- ##### ENUM GdkPixbufAlphaMode ##### -->
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1999-11-04 21:52:08 +00:00
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<para>
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These values can be passed to
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gdk_pixbuf_render_to_drawable_alpha() to control how the alpha
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chanel of an image should be handled. This function can create a
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bilevel clipping mask (black and white) and use it while painting
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the image. In the future, when the X Window System gets an alpha
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channel extension, it will be possible to do full alpha
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compositing onto arbitrary drawables. For now both cases fall
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back to a bilevel clipping mask.
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</para>
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@GDK_PIXBUF_ALPHA_BILEVEL: A bilevel clipping mask (black and white)
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will be created and used to draw the image. Pixels below 0.5 opacity
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will be considered fully transparent, and all others will be
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considered fully opaque.
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@GDK_PIXBUF_ALPHA_FULL: For now falls back to #GDK_PIXBUF_ALPHA_BILEVEL.
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In the future it will do full alpha compositing.
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1999-11-04 07:30:04 +00:00
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<!-- ##### FUNCTION gdk_pixbuf_render_to_drawable_alpha ##### -->
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<para>
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</para>
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@pixbuf:
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@drawable:
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@src_x:
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@src_y:
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@dest_x:
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@dest_y:
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@width:
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@height:
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@alpha_mode:
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@alpha_threshold:
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@dither:
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@x_dither:
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@y_dither:
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<!-- ##### FUNCTION gdk_pixbuf_render_to_drawable ##### -->
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<para>
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</para>
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@pixbuf:
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@drawable:
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@gc:
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@src_x:
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@src_y:
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@dest_x:
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@dest_y:
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@width:
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@height:
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@dither:
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@x_dither:
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@y_dither:
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<!-- ##### FUNCTION gdk_pixbuf_render_threshold_alpha ##### -->
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<para>
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</para>
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@pixbuf:
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@bitmap:
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@src_x:
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@src_y:
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@dest_x:
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@dest_y:
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@width:
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@height:
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2000-04-13 01:18:41 +00:00
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@alpha_threshold:
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1999-11-04 07:30:04 +00:00
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2000-01-17 01:48:21 +00:00
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<!-- ##### FUNCTION gdk_pixbuf_render_pixmap_and_mask ##### -->
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<para>
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</para>
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@pixbuf:
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@pixmap_return:
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@mask_return:
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@alpha_threshold:
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2000-04-13 01:18:41 +00:00
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<!--
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Local variables:
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mode: sgml
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sgml-parent-document: ("../gdk-pixbuf.sgml" "book" "refsect2" "")
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End:
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-->
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