N-archive/citra
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

PICA: Properly emulate 1-stage delay in the combiner buffer

Browse source 
This was discovered and verified by @fincs. The tev combiner buffer
actually lags behind by one stage, meaning stage 1 reads the initial
color, stage 2 reads stage 0's output, and so on.

Fixes character portraits in Fire Emblem: Awakening and world textures
in Zelda: ALBW. Closes #1140.
This commit is contained in:
Yuri Kunde Schlesner 2015-11-30 22:33:38 -08:00
parent bec9049597
commit e9c209ccc8
2 changed files with 19 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

13
src/video_core/rasterizer.cpp
View file

@ -498,7 +498,8 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0,
// with some basic arithmetic. Alpha combiners can be configured separately but work
// analogously.
Math::Vec4<u8> combiner_output;
Math::Vec4<u8> combiner_buffer = {
Math::Vec4<u8> combiner_buffer = {0, 0, 0, 0};
Math::Vec4<u8> next_combiner_buffer = {
regs.tev_combiner_buffer_color.r, regs.tev_combiner_buffer_color.g,
regs.tev_combiner_buffer_color.b, regs.tev_combiner_buffer_color.a
};
@ -747,14 +748,16 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0,
combiner_output[2] = std::min((unsigned)255, color_output.b() * tev_stage.GetColorMultiplier());
combiner_output[3] = std::min((unsigned)255, alpha_output * tev_stage.GetAlphaMultiplier());
combiner_buffer = next_combiner_buffer;
if (regs.tev_combiner_buffer_input.TevStageUpdatesCombinerBufferColor(tev_stage_index)) {
combiner_buffer.r() = combiner_output.r();
combiner_buffer.g() = combiner_output.g();
combiner_buffer.b() = combiner_output.b();
next_combiner_buffer.r() = combiner_output.r();
next_combiner_buffer.g() = combiner_output.g();
next_combiner_buffer.b() = combiner_output.b();
}
if (regs.tev_combiner_buffer_input.TevStageUpdatesCombinerBufferAlpha(tev_stage_index)) {
combiner_buffer.a() = combiner_output.a();
next_combiner_buffer.a() = combiner_output.a();
}
}

18
src/video_core/renderer_opengl/gl_shader_gen.cpp
View file

@ -311,11 +311,13 @@ static void WriteTevStage(std::string& out, const PicaShaderConfig& config, unsi
"clamp(alpha_output_" + index_name + " * " + std::to_string(stage.GetAlphaMultiplier()) + ".0, 0.0, 1.0));\n";
}
out += "combiner_buffer = next_combiner_buffer;\n";
if (config.TevStageUpdatesCombinerBufferColor(index))
out += "combiner_buffer.rgb = last_tex_env_out.rgb;\n";
out += "next_combiner_buffer.rgb = last_tex_env_out.rgb;\n";
if (config.TevStageUpdatesCombinerBufferAlpha(index))
out += "combiner_buffer.a = last_tex_env_out.a;\n";
out += "next_combiner_buffer.a = last_tex_env_out.a;\n";
}
std::string GenerateFragmentShader(const PicaShaderConfig& config) {
@ -334,12 +336,10 @@ layout (std140) uniform shader_data {
int alphatest_ref;
};
)";
uniform sampler2D tex[3];
out += "uniform sampler2D tex[3];\n";
out += "void main() {\n";
out += "vec4 combiner_buffer = tev_combiner_buffer_color;\n";
out += "vec4 last_tex_env_out = vec4(0.0);\n";
void main() {
)";
// Do not do any sort of processing if it's obvious we're not going to pass the alpha test
if (config.alpha_test_func == Regs::CompareFunc::Never) {
@ -347,6 +347,10 @@ layout (std140) uniform shader_data {
return out;
}
out += "vec4 combiner_buffer = vec4(0.0);\n";
out += "vec4 next_combiner_buffer = tev_combiner_buffer_color;\n";
out += "vec4 last_tex_env_out = vec4(0.0);\n";
for (size_t index = 0; index < config.tev_stages.size(); ++index)
WriteTevStage(out, config, (unsigned)index);