- Avoids double expansion when both the exp_tex flag is set AND the texture also is sampled as signed
- Should fix missing eyeballs in Mass Effect 1 with the previous sign expansion fix
- SRC0, SRC1 and SRC2 have different bits for precision modifiers all stored inside SRC1
- This explains the strange observed behavior of the MAD instruction which has 3 inputs
- Sometimes, usually with shaders that do pack/unpack operations, there is a write-to-self operation.
For example r0.xy = r0.xy
Obviously no new data was introduced into "r0" by this, so we should not mark the register as having new data.
- TODO: Investigate on realhw if self-reference is needed to "cast" the overlapping half registers to their full register counterparts.
- When the point sprite flag is set, overrides the input similar to the
2D mask. The returned X and Y values are always the gl_PointCoord values
for the fragment.
- Stacks with the 2D mask to override the z and w coordinates.
- Noticed a glitch on AMD hw and windows drivers where discard seems to affect entire 4x4 cells.
- Dead fragments (outside the primitive boundary) could have their discards trigger as they do not have proper access to variables.
- This introduces dead fragments along triangle edges, causing a diagonal line pattern across the screen that is very annoying.
- Fix 2D coordinate sampling of W coordinate.
W is actually HPOS.w and not 1. Z is however always 0.
- Optimize register usage a bit
Disassembling compiled SPV shows that global declaration results in less ops than using inout modifiers. Modifiers generate extra mov instructions.
- Fix reading of varying registers in FP
Different registers have different behavior
- Always write to varying registers. If a register is not written to, it is initialized to (0, 0, 0, 1)
- Reimplements two-sided lighting correctly without hacks
- Also bumps shader cache version
- TODO: Option to completely skip clamping in some architectures as it is not needed in most games
- Mostly affects older GPUs that do not have access to native fp16
TODO: Investigate the _s input modifier behaviour further, in case it can avoid generating zeroes from a MAD instruction.
x = MAD(+ve, -ve, -ve) with _s input modifier in BFBC expects result to be Non-zero
- Properly test for NaN and Inf when clamping down to fp16
- Optimize divsq a bit; mix(vec, vec, bvec) emits OpSelect which is what
we want here, instead of component-wise selection which is much slower.
- While mul(0, nan) = nan and 0 / 0 = nan, 0 / sqrt(0) = 0 because of hw
gremlins. normalize(0) is also nan so this behaviour does not work
around that particular case either which makes it even more baffling.
- The hw generates inaccurate values when doing perspective-correct
interpolation of vertex output attributes and makes the comparison (a ==
b) fail even when they are a fixed constant value.
- Increase equality tolerance when doing comparisons in fragment
shaders for NV cards only to work around this issue.
- Teepo fix
- The fixed-point D24S8 format does special Z clamping during compare which matches PS3 behaviour
- D32S8 is a floating point format and comparison with Dref > 1 always fails causing black edges/borders
- Improve support for float16_t by minimizing mixed inputs to functions
(ambiguous overloads)
- Minimize amount of downcasts in code by using opcode flags
- Re-enable float16_t support for vulkan
- Emulating f16 with f32 is not ideal and requires a lot of value clamping
- Using native data type can significantly improve performance and accuracy
- With openGL, check for the compatible extensions NV_gpu_shader5 and
AMD_gpu_shader_half_float
- With Vulkan, enable this functionality in the deviceFeatures if
applicable. (VK_KHR_shader_float16_int8 extension)
- Temporarily disable hw fp16 for vulkan
- Implements a mirror view of D24S8 data that accesses the stencil components.
Finishes the implementation of TEX2D_DEPTH_RGBA as the stencil component was previously missing from the reconstructed data
- Add a few missing destructors
Image classes are inherited a lot and I forgot to make the dtors virtual
- Per-channel conditional execution introduces RAW hazards all over the place
- Its cheaper to process both branches and select between the two
- Also improves ShaderVariable functionality to allow functionality such as match_size and taking complex variables as inputs
- Separate TXB from TXL: They are completely different!
- Properly perform TMU emulation in the fragment shader. Implemens SRGB conversion and alphakill at the moment
- Properly perform ROP emulation in the fragment shader. Implements FRAMEBUFFER_SRGB. While support on the chip looks to be incomplete (and wierd), it does work
- Document some more bits in SHADER_CONTROL register
- Export some debug information in the free texture register space components zw
Very useful when analysing renderdoc captures
- Enable shadow comparison on depth as long as compare function is active and texture is uploaded for depth read
Some engines (UE3) read all the components in the shader and use mul/mad with the result
