Almost all the virtual functions in Renderer are part of dolphin's
"graphics api abstraction layer", which has slowly formed over the
last decade or two.
Most of the work was done previously with the introduction of the
various "AbstractX" classes, associated with texture cache cleanups
and implementation of newer graphics APIs (Direct3D 12, Vulkan, Metal).
We are simply taking the last step and yeeting these functions out
of Renderer.
This "AbstractGfx" class is now completely agnostic of any details
from the flipper/hollywood GPU we are emulating, though somewhat
specialized.
(Will not build, this commit only contains changes outside VideoBackends)
Texture cache occasionally mutates textures for efficiency.
Which is awkward if we want to borrow those textures from texture cache
to do something else, such as a graphics debugger, or async presentation
on another thread.
Content locking provides a way to signal that the contents of a texture
cache entry should not change. Texture cache will be forced to use
alternative strategies.
The whole ownership model was getting a bit of a mess, with a some
of special cases to deal with. And I'm planning to make it even more
complex in the future.
So here is some upfront work to convert it over to reference counted
pointers.
This is the behavior in the x64 and ARM64 vertex loaders. I don't know if it makes sense (the whole skipped vertex system seems jank, but several games behave incorrectly without it).
Fixes incorrect logspam when the buffer needed to be reset on flushes (which we already were doing, but 52feed04dbf9d487138944ed834bd877620eef74 moved it to after the check was made). This is https://bugs.dolphin-emu.org/issues/10312.
I also converted it to an assert, as if this does happen, things are going to render incorrectly, so we want to make it obvious.
Otherwise, texelFetch() will use an out-of-bounds layer for game textures (that have 1 layer; EFB copies have 2 layers in stereoscopic 3D mode), which is undefined behavior (often resulting in a black image). The fast texture sampling path uses texture(), which always clamps (see https://www.khronos.org/opengl/wiki/Array_Texture#Access_in_shaders), so it was unaffected by this difference.
