Software: Invert backface test when viewport is positive

Fixes Jimmie Johnson's Anything with an Engine.
This commit is contained in:
Pokechu22 2020-12-21 18:20:32 -08:00
parent 089250fde6
commit 5b1c632862
1 changed files with 5 additions and 0 deletions

View File

@ -488,6 +488,11 @@ bool CullTest(const OutputVertexData* v0, const OutputVertexData* v1, const Outp
float normalZDir = (x0 * w2 - x2 * w0) * y1 + (x2 * y0 - x0 * y2) * w1 + (y2 * w0 - y0 * w2) * x1;
backface = normalZDir <= 0.0f;
// Jimmie Johnson's Anything with an Engine has a positive viewport, while other games have a
// negative viewport. The positive viewport does not require vertices to be vertically mirrored,
// but the backface test does need to be inverted for things to be drawn.
if (xfmem.viewport.ht > 0)
backface = !backface;
// TODO: Are these tests / the definition of backface above backwards?
if ((bpmem.genMode.cullmode == CullMode::Back || bpmem.genMode.cullmode == CullMode::All) &&