vulkan: Emulate depth clip control when extension is not available. (#762)

src/shader_recompiler/backend/spirv/emit_spirv_special.cpp

@@ -10,7 +10,21 @@ void EmitPrologue(EmitContext& ctx) {
     ctx.DefineBufferOffsets();
 }
 
-void EmitEpilogue(EmitContext& ctx) {}
+void ConvertDepthMode(EmitContext& ctx) {
+    const Id type{ctx.F32[1]};
+    const Id position{ctx.OpLoad(ctx.F32[4], ctx.output_position)};
+    const Id z{ctx.OpCompositeExtract(type, position, 2u)};
+    const Id w{ctx.OpCompositeExtract(type, position, 3u)};
+    const Id screen_depth{ctx.OpFMul(type, ctx.OpFAdd(type, z, w), ctx.Constant(type, 0.5f))};
+    const Id vector{ctx.OpCompositeInsert(ctx.F32[4], screen_depth, position, 2u)};
+    ctx.OpStore(ctx.output_position, vector);
+}
+
+void EmitEpilogue(EmitContext& ctx) {
+    if (ctx.stage == Stage::Vertex && ctx.runtime_info.vs_info.emulate_depth_negative_one_to_one) {
+        ConvertDepthMode(ctx);
+    }
+}
 
 void EmitDiscard(EmitContext& ctx) {
     ctx.OpDemoteToHelperInvocationEXT();

src/shader_recompiler/runtime_info.h

@@ -63,9 +63,10 @@ using VsOutputMap = std::array<VsOutput, 4>;
 
 struct VertexRuntimeInfo {
     boost::container::static_vector<VsOutputMap, 3> outputs;
+    bool emulate_depth_negative_one_to_one{};
 
     bool operator==(const VertexRuntimeInfo& other) const noexcept {
-        return true;
+        return emulate_depth_negative_one_to_one == other.emulate_depth_negative_one_to_one;
     }
 };
 

src/video_core/renderer_vulkan/vk_graphics_pipeline.cpp

@@ -125,7 +125,7 @@ GraphicsPipeline::GraphicsPipeline(const Instance& instance_, Scheduler& schedul
     };
 
     const vk::PipelineViewportStateCreateInfo viewport_info = {
-        .pNext = &clip_control,
+        .pNext = instance.IsDepthClipControlSupported() ? &clip_control : nullptr,
         .viewportCount = 1,
         .pViewports = &viewport,
         .scissorCount = 1,

src/video_core/renderer_vulkan/vk_instance.cpp

@@ -207,7 +207,7 @@ bool Instance::CreateDevice() {
     external_memory_host = add_extension(VK_EXT_EXTERNAL_MEMORY_HOST_EXTENSION_NAME);
     custom_border_color = add_extension(VK_EXT_CUSTOM_BORDER_COLOR_EXTENSION_NAME);
     add_extension(VK_KHR_PUSH_DESCRIPTOR_EXTENSION_NAME);
-    const bool depth_clip_control = add_extension(VK_EXT_DEPTH_CLIP_CONTROL_EXTENSION_NAME);
+    depth_clip_control = add_extension(VK_EXT_DEPTH_CLIP_CONTROL_EXTENSION_NAME);
     add_extension(VK_EXT_DEPTH_RANGE_UNRESTRICTED_EXTENSION_NAME);
     workgroup_memory_explicit_layout =
         add_extension(VK_KHR_WORKGROUP_MEMORY_EXPLICIT_LAYOUT_EXTENSION_NAME);

src/video_core/renderer_vulkan/vk_instance.h

@@ -117,6 +117,11 @@ public:
         return external_memory_host;
     }
 
+    /// Returns true when VK_EXT_depth_clip_control is supported
+    bool IsDepthClipControlSupported() const {
+        return depth_clip_control;
+    }
+
     /// Returns true when VK_EXT_color_write_enable is supported
     bool IsColorWriteEnableSupported() const {
         return color_write_en;
@@ -257,6 +262,7 @@ private:
     bool fragment_shader_barycentric{};
     bool shader_stencil_export{};
     bool external_memory_host{};
+    bool depth_clip_control{};
     bool workgroup_memory_explicit_layout{};
     bool color_write_en{};
     bool vertex_input_dynamic_state{};

src/video_core/renderer_vulkan/vk_pipeline_cache.cpp

@@ -69,28 +69,32 @@ void GatherVertexOutputs(Shader::VertexRuntimeInfo& info,
                    : (ctl.IsCullDistEnabled(7) ? VsOutput::CullDist7 : VsOutput::None));
 }
 
-Shader::RuntimeInfo BuildRuntimeInfo(Shader::Stage stage, const GraphicsPipelineKey& key,
-                                     const AmdGpu::Liverpool::Regs& regs) {
+Shader::RuntimeInfo PipelineCache::BuildRuntimeInfo(Shader::Stage stage) {
     auto info = Shader::RuntimeInfo{stage};
+    const auto& regs = liverpool->regs;
     switch (stage) {
     case Shader::Stage::Vertex: {
         info.num_user_data = regs.vs_program.settings.num_user_regs;
         info.num_input_vgprs = regs.vs_program.settings.vgpr_comp_cnt;
         GatherVertexOutputs(info.vs_info, regs.vs_output_control);
+        info.vs_info.emulate_depth_negative_one_to_one =
+            !instance.IsDepthClipControlSupported() &&
+            regs.clipper_control.clip_space == Liverpool::ClipSpace::MinusWToW;
         break;
     }
     case Shader::Stage::Fragment: {
         info.num_user_data = regs.ps_program.settings.num_user_regs;
-        std::ranges::transform(key.mrt_swizzles, info.fs_info.mrt_swizzles.begin(),
+        std::ranges::transform(graphics_key.mrt_swizzles, info.fs_info.mrt_swizzles.begin(),
                                [](Liverpool::ColorBuffer::SwapMode mode) {
                                    return static_cast<Shader::MrtSwizzle>(mode);
                                });
+        const auto& ps_inputs = regs.ps_inputs;
         for (u32 i = 0; i < regs.num_interp; i++) {
             info.fs_info.inputs.push_back({
-                .param_index = u8(regs.ps_inputs[i].input_offset.Value()),
-                .is_default = bool(regs.ps_inputs[i].use_default),
-                .is_flat = bool(regs.ps_inputs[i].flat_shade),
-                .default_value = u8(regs.ps_inputs[i].default_value),
+                .param_index = u8(ps_inputs[i].input_offset.Value()),
+                .is_default = bool(ps_inputs[i].use_default),
+                .is_flat = bool(ps_inputs[i].flat_shade),
+                .default_value = u8(ps_inputs[i].default_value),
             });
         }
         break;
@@ -327,7 +331,7 @@ vk::ShaderModule PipelineCache::CompileModule(Shader::Info& info,
 
 std::tuple<const Shader::Info*, vk::ShaderModule, u64> PipelineCache::GetProgram(
     Shader::Stage stage, Shader::ShaderParams params, u32& binding) {
-    const auto runtime_info = BuildRuntimeInfo(stage, graphics_key, liverpool->regs);
+    const auto runtime_info = BuildRuntimeInfo(stage);
     auto [it_pgm, new_program] = program_cache.try_emplace(params.hash);
     if (new_program) {
         Program* program = program_pool.Create(stage, params);

src/video_core/renderer_vulkan/vk_pipeline_cache.h

@@ -60,6 +60,7 @@ private:
                     std::string_view ext);
     vk::ShaderModule CompileModule(Shader::Info& info, const Shader::RuntimeInfo& runtime_info,
                                    std::span<const u32> code, size_t perm_idx, u32& binding);
+    Shader::RuntimeInfo BuildRuntimeInfo(Shader::Stage stage);
 
 private:
     const Instance& instance;