diff options
| author | Yuri Kunde Schlesner <yuriks@yuriks.net> | 2014-12-23 13:05:51 -0200 |
|---|---|---|
| committer | Yuri Kunde Schlesner <yuriks@yuriks.net> | 2014-12-29 02:08:11 -0200 |
| commit | 8369ee58035ca98f776428f6cccbcf987fee3bc9 (patch) | |
| tree | 3c1800823ffe55529ba6dbcba0c4407d2da625f2 /src/video_core/clipper.cpp | |
| parent | fe186d3a598837ba7337f06399dfb8ae7930a070 (diff) | |
Rasterizer: Pre-divide vertex attributes by W
Execute the division-by-W for perspective-correct interpolation of
values in the clipper, moving them out of the rasterization inner loop.
Diffstat (limited to 'src/video_core/clipper.cpp')
| -rw-r--r-- | src/video_core/clipper.cpp | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/src/video_core/clipper.cpp b/src/video_core/clipper.cpp index 0521ef866..1744066ba 100644 --- a/src/video_core/clipper.cpp +++ b/src/video_core/clipper.cpp @@ -91,10 +91,17 @@ static void InitScreenCoordinates(OutputVertex& vtx) viewport.zscale = float24::FromRawFloat24(registers.viewport_depth_range); viewport.offset_z = float24::FromRawFloat24(registers.viewport_depth_far_plane); + float24 inv_w = float24::FromFloat32(1.f) / vtx.pos.w; + vtx.color *= inv_w; + vtx.tc0 *= inv_w; + vtx.tc1 *= inv_w; + vtx.tc2 *= inv_w; + vtx.pos.w = inv_w; + // TODO: Not sure why the viewport width needs to be divided by 2 but the viewport height does not - vtx.screenpos[0] = (vtx.pos.x / vtx.pos.w + float24::FromFloat32(1.0)) * viewport.halfsize_x + viewport.offset_x; - vtx.screenpos[1] = (vtx.pos.y / vtx.pos.w + float24::FromFloat32(1.0)) * viewport.halfsize_y + viewport.offset_y; - vtx.screenpos[2] = viewport.offset_z - vtx.pos.z / vtx.pos.w * viewport.zscale; + vtx.screenpos[0] = (vtx.pos.x * inv_w + float24::FromFloat32(1.0)) * viewport.halfsize_x + viewport.offset_x; + vtx.screenpos[1] = (vtx.pos.y * inv_w + float24::FromFloat32(1.0)) * viewport.halfsize_y + viewport.offset_y; + vtx.screenpos[2] = viewport.offset_z - vtx.pos.z * inv_w * viewport.zscale; } void ProcessTriangle(OutputVertex &v0, OutputVertex &v1, OutputVertex &v2) { |