From d08e9b29e2f512a94da22399b9d68b7d2ad6c4a3 Mon Sep 17 00:00:00 2001 From: Lectem Date: Thu, 14 May 2015 15:49:40 +0200 Subject: VideoCore: Implement the DOT3_RGB combiner --- src/video_core/pica.h | 1 + src/video_core/rasterizer.cpp | 13 ++++++++++++- 2 files changed, 13 insertions(+), 1 deletion(-) (limited to 'src') diff --git a/src/video_core/pica.h b/src/video_core/pica.h index 46a7b21d..026b10a6 100644 --- a/src/video_core/pica.h +++ b/src/video_core/pica.h @@ -290,6 +290,7 @@ struct Regs { AddSigned = 3, Lerp = 4, Subtract = 5, + Dot3_RGB = 6, MultiplyThenAdd = 8, AddThenMultiply = 9, diff --git a/src/video_core/rasterizer.cpp b/src/video_core/rasterizer.cpp index c381c2bd..a6b7997c 100644 --- a/src/video_core/rasterizer.cpp +++ b/src/video_core/rasterizer.cpp @@ -641,7 +641,18 @@ static void ProcessTriangleInternal(const VertexShader::OutputVertex& v0, result = (result * input[2].Cast()) / 255; return result.Cast(); } - + case Operation::Dot3_RGB: + { + // Not fully accurate. + // Worst case scenario seems to yield a +/-3 error + // Some HW results indicate that the per-component computation can't have a higher precision than 1/256, + // while dot3_rgb( (0x80,g0,b0),(0x7F,g1,b1) ) and dot3_rgb( (0x80,g0,b0),(0x80,g1,b1) ) give different results + int result = ((input[0].r() * 2 - 255) * (input[1].r() * 2 - 255) + 128) / 256 + + ((input[0].g() * 2 - 255) * (input[1].g() * 2 - 255) + 128) / 256 + + ((input[0].b() * 2 - 255) * (input[1].b() * 2 - 255) + 128) / 256; + result = std::max(0, std::min(255, result)); + return { (u8)result, (u8)result, (u8)result }; + } default: LOG_ERROR(HW_GPU, "Unknown color combiner operation %d\n", (int)op); UNIMPLEMENTED(); -- cgit v1.2.3