We are used to use the texture parameter for all util draw calls,
but AMD seems to have a bug where they use the sampler parameter
of stage 0 if no sampler is bound to the used stage.
So as workaround (and a bit as nicer code), we now use sampler
objects everywhere.
Instead of abusing whatever VAO is previously bound, which might have
enabled arrays.
Only used in one instance currently, which fixes a crash with older
NVIDIA drivers.
This is pretty much a step backwards in our code. We used to use attributes in our PP shader system a long time ago but we changed it to attributeless
for code simplicity and cleanliness. This reimplements the attribute code path as an optional path to take in the case your system doesn't work with
attributeless rendering. In this case the only shipping drivers that we can know for sure supports attributeless rendering is the Nexus 5's v95 driver
that is included in the Android 5.0 image.
I hadn't planned on implementing a work around to get post processing working in these cases, but due to us force enabling the PP shader system at all
times it sort of went up on the priority list. We can't be having a supported platform black screening at all times can we?
We were generating a texture without ever setting the data to a known value.
This happened on the old code as well, just that PP shaders are receiving some love and people are using it and noticing some of its issues.
Seems mesa has a quirk where
define THING(x) (#x)
is the same as
define THING(x) (##x)
Didn't realize I messed it up since it just worked since I only tested on Mesa.
This class loads all the common PP shader configuration options and passes those options through to a inherited class that OpenGL or D3D will have.
Makes it so all the common code for PP shaders is in VideoCommon instead of duplicating the code across each backend.
