Add API to control per-framebuffer depth writing

Add framebuffer methods cogl_framebuffer_[gs]et_depth_write_enabled()
and backend bits to pass the state on to glDepthMask().

This allows us to enable or disable depth writing per-framebuffer, which
if disabled saves us some work in glClear(). When rendering, the flag
is combined with the pipeline's depth writing flag using a logical AND.

Depth writing is enabled by default.

https://bugzilla.gnome.org/show_bug.cgi?id=709827

Reviewed-by: Robert Bragg <robert@linux.intel.com>

0 files changed, 0 insertions, 0 deletions