This allows rendering to 3D textures with more than one slice.
Applications are allowed to render to more than one slice of a texture
using gl_Layer from a VTG shader.
This also requires reworking how 3D texture collisions are handled, for
now, this commit allows rendering to slices but not to miplevels. When a
render target attempts to write to a mipmap, we fallback to the previous
implementation (copying or flushing as needed).
- Fixes color correction 3D textures on UE4 games (rainbow effects).
- Allows Xenoblade games to render to 3D textures directly.
Games using D3D idioms can join images and samplers when a shader
executes, instead of baking them into a combined sampler image. This is
also possible on Vulkan.
One approach to this solution would be to use separate samplers on
Vulkan and leave this unimplemented on OpenGL, but we can't do this
because there's no consistent way of determining which constant buffer
holds a sampler and which one an image. We could in theory find the
first bit and if it's in the TIC area, it's an image; but this falls
apart when an image or sampler handle use an index of zero.
The used approach is to track for a LOP.OR operation (this is done at an
IR level, not at an ISA level), track again the constant buffers used as
source and store this pair. Then, outside of shader execution, join
the sample and image pair with a bitwise or operation.
This approach won't work on games that truly use separate samplers in a
meaningful way. For example, pooling textures in a 2D array and
determining at runtime what sampler to use.
This invalidates OpenGL's disk shader cache :)
- Used mostly by D3D ports to Switch
Drop MemoryBarrier from the buffer cache and use Maxwell3D's register
WaitForIdle.
To implement this on OpenGL we just call glMemoryBarrier with the
necessary bits.
Vulkan lacks this synchronization primitive, so we set an event and
immediately wait for it. This is not a pretty solution, but it's what
Vulkan can do without submitting the current command buffer to the queue
(which ends up being more expensive on the CPU).
Using deko3d as reference:
4e47ba0013/source/maxwell/gpu_3d_state.cpp (L42)
We were using bits 3 and 4 to determine depth clamping, but these are
the same both enabled and disabled:
state->depthClampEnable ? 0x101A : 0x181D
The same happens on Nvidia's OpenGL driver, where they do something like
this (default capabilities, GL 4.5 compatibility):
(state & DEPTH_CLAMP) != 0 ? 0x201a : 0x281c
There's always a difference between the first bits in this register, but
bit 11 is consistently disabled on both deko3d/NVN and OpenGL. This
commit changes yuzu's behaviour to use bit 11 to determine depth
clamping.
- Fixes depth issues on Super Mario Odyssey's intro.
On NVN buffers can be enabled but have no size. According to deko3d and
the behavior we see in Animal Crossing: New Horizons these buffers get
the special address of 0x1000 and limit themselves to 0xfff.
Implement buffers without a size by binding a null buffer to OpenGL
without a side.
1d1930beea/source/maxwell/gpu_3d_vbo.cpp (L62-L63)
Layered framebuffer attachments is a feature that allows applications to
write attach layered textures to a single attachment. What layer the
fragments are written to is decided from the shader using gl_Layer.
Instead of waiting immediately for executed commands, defer the query
until the guest CPU reads it. This way we get closer to what the guest
program is doing.
To archive this we have to build a dependency queue, because host APIs
(like OpenGL and Vulkan) use ranged queries instead of counters like
NVN.
Waiting for queries implicitly uses fences and this requires a command
being queued, otherwise the driver will lock waiting until a timeout. To
fix this when there are no commands queued, we explicitly call glFlush.
