On all platforms, this would result in out of bounds accesses when getting the component sizes (which uses stuff from VertexLoader_Position.h/VertexLoader_TextCoord.h/VertexLoader_Normal.h). On platforms other than x64 and ARM64, this would also be out of bounds accesses when getting function pointers for the non-JIT vertex loader (in VertexLoader_Position.cpp etc.). Usually both of these would get data from other entries in the same multi-dimensional array, but the last few entries would be truly out of bounds. This does mean that an out of bounds function pointer can be called on platforms that don't have a JIT vertex loader, but it is limited to invalid component formats with values 5/6/7 due to the size of the bitfield the formats come from, so it seems unlikely that this could be exploited in practice.
This issue affects a few games; Def Jam: Fight for New York (https://bugs.dolphin-emu.org/issues/12719) and Fifa Street are known to be affected.
I have not done any hardware testing for this PR specifically, though I *think* I previously determined that at least a value of 5 behaves the same as float (4). That's what I implemented in any case. I did previously determine that both Def Jam: Fight for New York and Fifa Street use an invalid normal format, but don't actually have lighting enabled when that normal vector is used, so it doesn't change rendering in practice.
The color component format also has two invalid values, but VertexLoader_Color.h/.cpp do check for those invalid ones and return a default value instead of doing an out of bounds access.
Dolphin no longer supports Windows 7, so the fact that there are (were?)
more people who use Windows 7 than who use a GPU that doesn't support
the required feature is no longer relevant.
To further increase the accuracy of the post process phase, I've added (scRGB) HDR support, which is necessary
to fully display the PAL and NTSC-J color spaces, and also to improve the quality of post process texture samplings and
do them in linear space instead of gamma space (which is very important when playing at low resolutions).
For SDR, the quality is also slightly increased, at least if any post process runs, as the buffer is now
R10G10B10A2 (on Vulkan, DX11 and DX12) if supported; previously it was R8G8B8A8 but the alpha bits were wasted.
Gamma correction is arguably the most important thing as Dolphin on Windows outputted in "sRGB" (implicitly)
as that's what Windows expects by default, though sRGB gamma is very different from the gamma commonly used
by video standards dating to the pre HDR era (roughly gamma 2.35).
Additionally, the addition of HDR support (which is pretty straight forward and minimal), added support for
our own custom AutoHDR shaders, which would allow us to achieve decent looking HDR in Dolphin games without
having to use SpecialK or Windows 11 AutoHDR. Both of which don't necessarily play nice with older games
with strongly different and simpler lighting. HDR should also be supported in Linux.
Development of my own AutoHDR shader is almost complete and will come next.
This has been carefully tested and there should be no regression in any of the different features that Dolphin
offers, like multisampling, stereo rendering, other post processes, etc etc.
Fixes: https://bugs.dolphin-emu.org/issues/8941
Co-authored-by: EndlesslyFlowering <EndlesslyFlowering@protonmail.com>
Co-authored-by: Dogway <lin_ares@hotmail.com>
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.
