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.
The maintainer compiler flags we use trigger warnings and errors
in the autogenerated code that gtk-doc creates to scan the header
and source files. Since we cannot control that, and we must run
a distcheck with both --enable-gtk-doc and --enable-maintainer-flags
turned on, we need to use less-strict compiler flags when inside
the doc/reference subdirectories.
The way to do this is to split the maintainer compiler flags into
their own Makefile variable, called MAINTAINER_CFLAGS. The we
can use $(MAINTAINER_CFLAGS) in the INCLUDES or _CFLAGS sections
of each part of the source directories we wish to check with the
anal retentiveness suited for maintainers.
Bug #919 - Replacement pango renderer (Neil Roberts)
* clutter/clutter-backend.h:
* clutter/clutter-backend.c:
(clutter_backend_set_font_options),
(clutter_backend_get_font_options): Add the ability to set
the cairo_font_options_t* for the backend at construction
time, so that backend implementations can have their own
options.
* clutter/clutter-color.c: Include pango/pango-attributes.h
for the pango_color_parse() function.
* clutter/clutter-label.c:
(clutter_label_ensure_layout),
(clutter_label_init), (clutter_label_set_text),
(clutter_label_set_font_name), (clutter_label_set_ellipsize),
(clutter_label_set_use_markup): Ensure that the cache is
always primed when the Label changes; this makes sure that
the cache is rebuilt outside the paint run, which should
make the painting perform better especially on embedded
devices.
* clutter/clutter-entry.c:
(clutter_entry_ensure_layout),
(clutter_entry_init), (clutter_entry_set_text),
(clutter_entry_set_font_name): Ditto as above.
* clutter/clutter-private.h:
* clutter/clutter-main.[ch]: Create the font-map inside the
main context; add two new functions:
clutter_clear_glyph_cache()
clutter_set_use_mipmapped_text()
that control the glyphs cache.
* clutter/pango/Makefile.am:
* clutter/pango/pangoclutter-fontmap.c:
* clutter/pango/pangoclutter-private.h:
* clutter/pango/pangoclutter-render.c:
* clutter/pango/pangoclutter.h: Rewrite the Pango renderer
using a PangoCairo context and saving the glyphs inside a
more efficient cache.
* configure.ac: Depend on pangocairo instead of pangoft2.
* clutter/Makefile.am: Update the regular expression to match
all the namespaces we actually use. Thanks to Neil Roberts for
spotting this. A make distclean is needed.
* clutter/cogl/gl/Makefile.am:
* clutter/cogl/gles/Makefile.am:
* clutter/json/Makefile.am:
* clutter/pango/Makefile.am: Revert previous commit.
* clutter/cogl/Makefile.am:
* clutter/cogl/gl/Makefile.am:
* clutter/cogl/gles/Makefile.am:
* clutter/json/Makefile.am:
* clutter/pango/Makefile.am: Fix the visibility of all the
symbols, for the main library and the statically linked ones.
* clutter/Makefile.am:
* clutter/clutter-actor.c:
* clutter/clutter-clone-texture.c:
* clutter/clutter-rectangle.c:
* clutter/clutter-stage.c:
* clutter/clutter-texture.c:
* clutter/cogl/cogl.h:
* clutter/cogl/gl/Makefile.am:
* clutter/cogl/gl/cogl-defines.h:
* clutter/cogl/gl/cogl.c:
* clutter/cogl/gles/Makefile.am:
* clutter/cogl/gles/cogl-defines.h:
* clutter/cogl/gles/cogl.c:
* clutter/glx/Makefile.am:
* clutter/glx/clutter-stage-glx.c:
* clutter/pango/Makefile.am:
* clutter/pango/pangoclutter-render.c:
* configure.ac:
Add initial 'cogl' implementation. 'cogl' is a simple abstration
layer over GL and GL/ES used by clutter internally. It should
eventually allow clutter applications to be run on both GL and GL/ES
with just a recompile as well as provide more debugging and potentially
profiling information for GL and GL/ES usage.
This commit contains the initial GL implementation.
