From 5b1c6328626557bbb25fe290738e7c6e7069af68 Mon Sep 17 00:00:00 2001 From: Pokechu22 Date: Mon, 21 Dec 2020 18:20:32 -0800 Subject: [PATCH] Software: Invert backface test when viewport is positive Fixes Jimmie Johnson's Anything with an Engine. --- Source/Core/VideoBackends/Software/Clipper.cpp | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/Source/Core/VideoBackends/Software/Clipper.cpp b/Source/Core/VideoBackends/Software/Clipper.cpp index 417bc63fa3..41a5e07d07 100644 --- a/Source/Core/VideoBackends/Software/Clipper.cpp +++ b/Source/Core/VideoBackends/Software/Clipper.cpp @@ -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) &&