bb156970de
When rendering a pango layout CoglPangoRenderer now records the operations into a list called a CoglPangoDisplayList. The entries in the list are either glyph renderings from a texture, rectangles or trapezoids. Multiple consecutive glyph renderings from the same glyph cache texture are combined into a single entry. Note the CoglPangoDisplayList has nothing to do with a GL display list. After the display list is built it is attached to the PangoLayout with g_object_set_qdata so that next time the layout is rendered it can bypass rebuilding it. The glyph rendering entries are drawn via a VBO. The VBO is attached to the display list so it can be used multiple times. This makes the common case of rendering a PangoLayout contained in a single texture subsequent times usually boil down to a single call to glDrawArrays with an already uploaded VBO. The VBOs are accessed via the cogl_vertex_buffer API so if VBOs are not available in GL it will resort to a fallback. Note this will fall apart if the pango layout is altered after the first render. I can't find a way to detect when the layout is altered. However this won't affect ClutterText because it creates a new PangoLayout whenever any properties are changed. |
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| .. | ||
| cogl-pango-display-list.c | ||
| cogl-pango-display-list.h | ||
| cogl-pango-fontmap.c | ||
| cogl-pango-glyph-cache.c | ||
| cogl-pango-glyph-cache.h | ||
| cogl-pango-private.h | ||
| cogl-pango-render.c | ||
| cogl-pango.h | ||
| Makefile.am | ||