From ad989750fc042ae1b9813f1d6be11b4ff4e2dd8e Mon Sep 17 00:00:00 2001
From: PixelyIon <pixelyion@protonmail.com>
Date: Sat, 7 May 2022 03:22:21 +0530
Subject: [PATCH] Implement Maxwell3D Point Sprite Size

Implements register state that corresponds to the size of a single point sprite in Maxwell 3D, this is emitted by the shader compiler in the preamble but needs to be only applied if the input topology is a point primitive and it is invalid to set the point size in any other case.
---
 .../gpu/interconnect/graphics_context.h       | 19 +++++++++++++++++++
 .../skyline/soc/gm20b/engines/maxwell_3d.cpp  |  4 ++++
 2 files changed, 23 insertions(+)

diff --git a/app/src/main/cpp/skyline/gpu/interconnect/graphics_context.h b/app/src/main/cpp/skyline/gpu/interconnect/graphics_context.h
index e180e6c5..c33b8aaa 100644
--- a/app/src/main/cpp/skyline/gpu/interconnect/graphics_context.h
+++ b/app/src/main/cpp/skyline/gpu/interconnect/graphics_context.h
@@ -1064,6 +1064,10 @@ namespace skyline::gpu::interconnect {
                 if (!pipelineStage.enabled)
                     continue;
 
+                auto fixedPointSize{runtimeInfo.fixed_state_point_size};
+                if (fixedPointSize && pipelineStage.vkStage != vk::ShaderStageFlagBits::eVertex && pipelineStage.vkStage != vk::ShaderStageFlagBits::eGeometry)
+                    runtimeInfo.fixed_state_point_size.reset(); // Only vertex/geometry stages are allowed to have a point size
+
                 if (pipelineStage.needsRecompile || bindings.unified != pipelineStage.bindingBase || pipelineStage.previousStageStores.mask != runtimeInfo.previous_stage_stores.mask) {
                     pipelineStage.previousStageStores = runtimeInfo.previous_stage_stores;
                     pipelineStage.bindingBase = bindings.unified;
@@ -1071,6 +1075,8 @@ namespace skyline::gpu::interconnect {
                     pipelineStage.bindingLast = bindings.unified;
                 }
 
+                runtimeInfo.fixed_state_point_size = fixedPointSize;
+
                 auto &program{pipelineStage.program->program};
                 runtimeInfo.previous_stage_stores = program.info.stores;
                 if (program.is_geometry_passthrough)
@@ -1844,6 +1850,7 @@ namespace skyline::gpu::interconnect {
         /* Input Assembly */
       private:
         vk::PipelineInputAssemblyStateCreateInfo inputAssemblyState{};
+        float pointSpriteSize{}; //!< The size of a point sprite to be defined in the shader
 
         void ValidatePrimitiveRestartState() {
             if (inputAssemblyState.primitiveRestartEnable) {
@@ -1907,6 +1914,12 @@ namespace skyline::gpu::interconnect {
 
             inputAssemblyState.topology = vkTopology;
             needsQuadConversion = isQuad;
+
+            if (shaderTopology == ShaderCompiler::InputTopology::Points)
+                UpdateRuntimeInformation(runtimeInfo.fixed_state_point_size, std::make_optional(pointSpriteSize), maxwell3d::PipelineStage::Vertex, maxwell3d::PipelineStage::Geometry);
+            else if (runtimeInfo.input_topology == ShaderCompiler::InputTopology::Points)
+                UpdateRuntimeInformation(runtimeInfo.fixed_state_point_size, std::optional<float>{}, maxwell3d::PipelineStage::Vertex, maxwell3d::PipelineStage::Geometry);
+
             UpdateRuntimeInformation(runtimeInfo.input_topology, shaderTopology, maxwell3d::PipelineStage::Geometry);
         }
 
@@ -1914,6 +1927,12 @@ namespace skyline::gpu::interconnect {
             inputAssemblyState.primitiveRestartEnable = enable;
         }
 
+        void SetPointSpriteSize(float size) {
+            pointSpriteSize = size;
+            if (runtimeInfo.input_topology == ShaderCompiler::InputTopology::Points)
+                UpdateRuntimeInformation(runtimeInfo.fixed_state_point_size, std::make_optional(size), maxwell3d::PipelineStage::Vertex, maxwell3d::PipelineStage::Geometry);
+        }
+
         /* Tessellation */
       private:
         vk::PipelineTessellationStateCreateInfo tessellationState{};
diff --git a/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.cpp b/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.cpp
index 5bde3d22..88dd5733 100644
--- a/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.cpp
+++ b/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.cpp
@@ -101,6 +101,10 @@ namespace skyline::soc::gm20b::engine::maxwell3d {
                 static_assert(type::RenderTargetCount == 8 && type::RenderTargetCount < BOOST_PP_LIMIT_REPEAT);
                 #undef RENDER_TARGET_ARRAY
 
+                ENGINE_CASE(pointSpriteSize, {
+                    context.SetPointSpriteSize(pointSpriteSize);
+                })
+
                 ENGINE_CASE(depthTargetEnable, {
                     context.SetDepthRenderTargetEnabled(depthTargetEnable);
                 })