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More docs work - Federico

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Arturo Espinosa
1999-11-04 21:52:08 +00:00
parent 76f716cec7
commit 9d8da16ee9
17 changed files with 241 additions and 89 deletions
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23
gdk/gdkpixbuf-render.c
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@ -176,10 +176,12 @@ remove_alpha (ArtPixBuf *apb, int x, int y, int width, int height, int *rowstrid
* 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 scrolling (so you can redraw half an image but keep the
* dithering "lined up" between the part you drew first and the part you drew previously).
* For unscrolled images, the offset can always be 0.
* 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,
@ -254,12 +256,13 @@ gdk_pixbuf_render_to_drawable (GdkPixbuf *pixbuf,
* 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.
*
* This function has a performance penalty; it makes two synchronous
* round trips to the X server (creating a bitmask and a GC), and it
* draws the contents of the bitmask. If performance is crucial,
* consider handling alpha yourself and using
* gdk_pixbuf_render_to_drawable(). On the other hand it's more convenient
* than gdk_pixbuf_render_to_drawable() because it handles the alpha channel.
* 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.
**/
void
gdk_pixbuf_render_to_drawable_alpha (GdkPixbuf *pixbuf, GdkDrawable *drawable,