- NV GPUs have a tendancy to be off by a very small margin, breaking rendering when greaterThan/lessThan checks are used.
- NOTE: Currently this setting is using the sRGB flag which indicates 8-bit output.
Only one game is currently known to care about this behaviour so this is good enough for now.
- Mainly affects nvidia where x/w * w can sometimes return a value smaller than x.
In such conditions, floor(x) will return x-1 if x is an integer which is horribly wrong and exaggerates minor precision drift to great proportions.
- Some things can be present in program env but not ucode state
e.g A texture can be active and bound in a redirected manner but not actually be used in ucode
In such a case, only the ucode analysis or decompilation can decide whether to inject decoding routines
- 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
- 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
- Remove string comparisons from the hot-path!
- Use attribute streaming and push constants to avoid forcing a descriptor block copy every other draw call/pass.
While this isn't so bad on nvidia cards, it makes AMD cards a slideshow.
- 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
