GLES doesn't support the GL_BGRA + GL_UNSIGNED_INT_24_8 hack that
we use on desktop OpenGL to upload textures directly in the cairo
pixel format. This adds the required conversions to all the places
that currently need it.
We also add a data_format to the internal gdk_gl_context_upload_texture()
function to make it clearer what the format are. Currently it is always
the cairo image surface format, but eventually we want to support other
formats so that we can avoid some of the unnecessary conversions we do.
Also, the current gdk_gl_context_upload_texture() code always converts
to a cairo format and uploads that like we did before. Later commits
will allow this to use other upload formats that gl supports to avoid
conversions.
Return a pointer to the IconData struct. This is
closer to the glyph cache api, and will allow us
to add similar shortcuts. For now, just store
texture coords in the form we need, avoiding
converting them over and over.
Remember which atlases were removed, and only
check those when looking for icons or glyphs
to remove. For most frames, we don't have to
check at all since no atlases were removed.
We can't just assume that the pointer we'se using as a cache key will
stay unique forever. The texture might be freed, and a later allocated
texture might have the same addres now, causing the cache to return
incorrect results.
Use the same texture atlases to back both
the glyph and icon caches, and unify their
sizes and management. Store big glyphs
in separate textures, so all atlases have
the same size. Tweak some of the eviction
parameters.
We share the caches across all GL contexts
on a display, unless the GSK_NO_SHARED_CACHES
env var is set.
