I think this is a relic of D3D9. D3D11 and D3D12 seem to work fine without it. Plus, ViewportCorrectionMatrix just didn't work correctly (at least with the viewports being generated by the new scissor code).
These aren't particularly useful, and make the code a bit more confusing. If for some reason someone wants to test what happens when these functions are disabled, it's easier to just edit the code that implements them. They aren't exposed in the UI, so one would need to restart Dolphin to do it anyways.
Specifically, when using Manual Texture Sampling, if textures sizes don't match the size the game specifies, things previously broke. That can happen with custom textures, and also with scaled EFB copies at non-native IRs. It breaks most obviously by not scaling the texture coordinates (so only part of the texture shows up), but the hardware wrapping functionality also assumes texture sizes are a power of 2 (or else it will behave weirdly in a way that matches how hardware behaves weirdly). The fix is to provide alternative texture wrapping logic when custom texture sizes are possible.
SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Currently, we do not display every second frame in 25fps/30fps games
which run to vsync. This improves performance as there's less rendering
for the GPU to perform, but when combined with vsync, could cause frame
pacing issues.
This commit adds an option to force every frame generated by the console
to be displayed to the host, which may improve pacing for these games.
This header doesn't actually make use of MathUtil.h within itself, so
this can be removed. Many other source files used VideoCommon.h as an
indirect include to include MathUtil.h, so these includes can also be
adjusted.
While we're at it, we can also migrate valid inclusions of VideoCommon.h
into cpp files where it can feasibly be done to minimize propagating it
via other headers.
Also makes y_scale a dynamic parameter for EFB copies, as it doesn't
make sense to keep it as part of the uid, otherwise we're generating
redundant shaders.
Skip ubershader mode works the same as hybrid ubershaders in that the
shaders are compiled asynchronously. However, instead of using the
ubershader to draw the object, it skips it entirely until the
specialized shader is made available.
This mode will likely result in broken effects where a game creates an
EFB copy, and does not redraw it every frame. Therefore, it is not a
recommended option, however, it may result in better performance on
low-end systems.
This enables shaders to be compiled while the game is starting, instead
of blocking startup. If a shader is needed before it is compiled,
emulation will block.
The option is named DisableCopyToVRAM under the Hacks section in
GFX.ini. It is intentionally not exposed to the GUI, as users should not
need to use it under normal circumstances. The main use is debugging
issues in the EFB-to-RAM shaders.
Otherwise we might get UB if the value we cast is larger than the
max value of the underlying type that the compiled picked for the enum.
I haven't done any extensive check through Dolphin to find cases
of this, I'm just fixing the cases I already know of.