Avoids compiling shader variants in the host driver if they will never
be used for rendering.
Wait to register shaders with the host GL driver until after shader
dependencies have been resolved and the selected set of variants is
known to be used for rendering.
The cost of this workaround is taht TGSI to GLSL conversion is still
performed for every variant (observed to happen twice for every
vertex/fragment shader in some cases), but this is expected to be much
cheaper than calling out to the host driver to compile unused variants.
Workaround for #180.
Signed-off-by: Ryan Neph <ryanneph@google.com>
Reviewed-by: Gert Wollny <gert.wollny@collabora.com>
Ryan Neph