[Re-introduced] Color output handling in SPIR-V emission

src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp

@@ -491,9 +491,24 @@ void EmitSetPatch(EmitContext& ctx, IR::Patch patch, Id value) {
 }
 
 void EmitSetFragColor(EmitContext& ctx, u32 index, u32 component, Id value) {
+    const AttributeType output_type{ctx.runtime_info.color_output_types[index]};
+    Id pointer_type{ctx.output_f32};
+    Id store_value{value};
+    switch (output_type) {
+    case AttributeType::SignedInt:
+        pointer_type = ctx.output_s32;
+        store_value = ctx.OpBitcast(ctx.S32[1], value);
+        break;
+    case AttributeType::UnsignedInt:
+        pointer_type = ctx.output_u32;
+        store_value = ctx.OpBitcast(ctx.U32[1], value);
+        break;
+    default:
+        break;
+    }
     const Id component_id{ctx.Const(component)};
-    const Id pointer{ctx.OpAccessChain(ctx.output_f32, ctx.frag_color.at(index), component_id)};
-    ctx.OpStore(pointer, value);
+    const Id pointer{ctx.OpAccessChain(pointer_type, ctx.frag_color.at(index), component_id)};
+    ctx.OpStore(pointer, store_value);
 }
 
 void EmitSetSampleMask(EmitContext& ctx, Id value) {

src/shader_recompiler/backend/spirv/spirv_emit_context.cpp

@@ -563,6 +563,7 @@ void EmitContext::DefineCommonTypes(const Info& info) {
 
     output_f32 = Name(TypePointer(spv::StorageClass::Output, F32[1]), "output_f32");
     output_u32 = Name(TypePointer(spv::StorageClass::Output, U32[1]), "output_u32");
+    output_s32 = Name(TypePointer(spv::StorageClass::Output, S32[1]), "output_s32");
 
     if (info.uses_int8 && profile.support_int8) {
         AddCapability(spv::Capability::Int8);
@@ -1699,7 +1700,18 @@ void EmitContext::DefineOutputs(const IR::Program& program) {
             if (!info.stores_frag_color[index] && !profile.need_declared_frag_colors) {
                 continue;
             }
-            frag_color[index] = DefineOutput(*this, F32[4], std::nullopt);
+            const AttributeType output_type{runtime_info.color_output_types[index]};
+            const Id vec_type = [&, output_type]() -> Id {
+                switch (output_type) {
+                case AttributeType::SignedInt:
+                    return S32[4];
+                case AttributeType::UnsignedInt:
+                    return U32[4];
+                default:
+                    return F32[4];
+                }
+            }();
+            frag_color[index] = DefineOutput(*this, vec_type, std::nullopt);
             Decorate(frag_color[index], spv::Decoration::Location, index);
             Name(frag_color[index], fmt::format("frag_color{}", index));
         }

src/shader_recompiler/backend/spirv/spirv_emit_context.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -246,6 +249,7 @@ public:
 
     Id output_f32{};
     Id output_u32{};
+    Id output_s32{};
 
     Id image_buffer_type{};
     Id image_u32{};

src/shader_recompiler/runtime_info.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -80,6 +83,7 @@ struct TransformFeedbackVarying {
 
 struct RuntimeInfo {
     std::array<AttributeType, 32> generic_input_types{};
+    std::array<AttributeType, 8> color_output_types{};
     VaryingState previous_stage_stores;
     std::map<IR::Attribute, IR::Attribute> previous_stage_legacy_stores_mapping;
 

src/video_core/renderer_vulkan/vk_pipeline_cache.cpp

@@ -36,6 +36,7 @@
 #include "video_core/renderer_vulkan/vk_scheduler.h"
 #include "video_core/renderer_vulkan/vk_shader_util.h"
 #include "video_core/renderer_vulkan/vk_update_descriptor.h"
+#include "video_core/surface.h"
 #include "video_core/shader_cache.h"
 #include "video_core/shader_environment.h"
 #include "video_core/shader_notify.h"
@@ -105,6 +106,21 @@ Shader::CompareFunction MaxwellToCompareFunction(Maxwell::ComparisonOp compariso
     return {};
 }
 
+Shader::AttributeType RenderTargetAttributeType(Tegra::RenderTargetFormat format) {
+    if (format == Tegra::RenderTargetFormat::NONE) {
+        return Shader::AttributeType::Float;
+    }
+    const auto pixel_format{
+        VideoCore::Surface::PixelFormatFromRenderTargetFormat(format)};
+    if (!VideoCore::Surface::IsPixelFormatInteger(pixel_format)) {
+        return Shader::AttributeType::Float;
+    }
+    if (VideoCore::Surface::IsPixelFormatSignedInteger(pixel_format)) {
+        return Shader::AttributeType::SignedInt;
+    }
+    return Shader::AttributeType::UnsignedInt;
+}
+
 VkShaderStageFlagBits StageToVkStage(Shader::Stage stage) {
     switch (stage) {
     case Shader::Stage::VertexA:
@@ -249,6 +265,10 @@ Shader::RuntimeInfo MakeRuntimeInfo(std::span<const Shader::IR::Program> program
         info.alpha_test_func = MaxwellToCompareFunction(
             key.state.UnpackComparisonOp(key.state.alpha_test_func.Value()));
         info.alpha_test_reference = std::bit_cast<float>(key.state.alpha_test_ref);
+        for (size_t index = 0; index < Maxwell::NumRenderTargets; ++index) {
+            const auto format = static_cast<Tegra::RenderTargetFormat>(key.state.color_formats[index]);
+            info.color_output_types[index] = RenderTargetAttributeType(format);
+        }
         break;
     default:
         break;