Implement primitive topology in OpenGL, Metal, and D3D12 backends

src/backend/d3d12/CommandBufferD3D12.cpp

@@ -399,7 +399,6 @@ namespace d3d12 {
                     {
                         DrawArraysCmd* draw = commands.NextCommand<DrawArraysCmd>();
 
-                        commandList->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
                         commandList->DrawInstanced(
                             draw->vertexCount,
                             draw->instanceCount,
@@ -413,7 +412,6 @@ namespace d3d12 {
                     {
                         DrawElementsCmd* draw = commands.NextCommand<DrawElementsCmd>();
 
-                        commandList->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
                         commandList->DrawIndexedInstanced(
                             draw->indexCount,
                             draw->instanceCount,
@@ -464,6 +462,7 @@ namespace d3d12 {
 
                         commandList->SetGraphicsRootSignature(layout->GetRootSignature().Get());
                         commandList->SetPipelineState(pipeline->GetPipelineState().Get());
+                        commandList->IASetPrimitiveTopology(pipeline->GetD3D12PrimitiveTopology());
 
                         bindingTracker.SetInheritedBindGroups(commandList, lastLayout, layout);
 

src/backend/d3d12/RenderPipelineD3D12.cpp

@@ -25,8 +25,27 @@
 namespace backend {
 namespace d3d12 {
 
+    namespace {
+        D3D12_PRIMITIVE_TOPOLOGY D3D12PrimitiveTopology(nxt::PrimitiveTopology primitiveTopology) {
+            switch (primitiveTopology) {
+                case nxt::PrimitiveTopology::Point:
+                    return D3D_PRIMITIVE_TOPOLOGY_POINTLIST;
+                case nxt::PrimitiveTopology::Line:
+                    return D3D_PRIMITIVE_TOPOLOGY_LINELIST;
+                case nxt::PrimitiveTopology::LineStrip:
+                    return D3D_PRIMITIVE_TOPOLOGY_LINESTRIP;
+                case nxt::PrimitiveTopology::Triangle:
+                    return D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;
+                case nxt::PrimitiveTopology::TriangleStrip:
+                    return D3D_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP;
+                default:
+                    UNREACHABLE();
+            }
+        }
+    }
+
     RenderPipeline::RenderPipeline(RenderPipelineBuilder* builder)
-        : RenderPipelineBase(builder) {
+        : RenderPipelineBase(builder), d3d12PrimitiveTopology(D3D12PrimitiveTopology(GetPrimitiveTopology())) {
         uint32_t compileFlags = 0;
 #if defined(_DEBUG)
         // Enable better shader debugging with the graphics debugging tools.
@@ -132,6 +151,10 @@ namespace d3d12 {
         ASSERT_SUCCESS(device->GetD3D12Device()->CreateGraphicsPipelineState(&descriptor, IID_PPV_ARGS(&pipelineState)));
     }
 
+    D3D12_PRIMITIVE_TOPOLOGY RenderPipeline::GetD3D12PrimitiveTopology() const {
+        return d3d12PrimitiveTopology;
+    }
+
     ComPtr<ID3D12PipelineState> RenderPipeline::GetPipelineState() {
         return pipelineState;
     }

src/backend/d3d12/RenderPipelineD3D12.h

@@ -26,9 +26,11 @@ namespace d3d12 {
         public:
             RenderPipeline(RenderPipelineBuilder* builder);
 
+            D3D12_PRIMITIVE_TOPOLOGY GetD3D12PrimitiveTopology() const;
             ComPtr<ID3D12PipelineState> GetPipelineState();
 
         private:
+            D3D12_PRIMITIVE_TOPOLOGY d3d12PrimitiveTopology;
             ComPtr<ID3D12PipelineState> pipelineState;
     };
 

src/backend/metal/CommandBufferMTL.mm

@@ -279,7 +279,7 @@ namespace metal {
 
                         ASSERT(encoders.render);
                         [encoders.render
-                            drawPrimitives:MTLPrimitiveTypeTriangle
+                            drawPrimitives:lastRenderPipeline->GetMTLPrimitiveTopology()
                             vertexStart:draw->firstVertex
                             vertexCount:draw->vertexCount
                             instanceCount:draw->instanceCount
@@ -293,7 +293,7 @@ namespace metal {
 
                         ASSERT(encoders.render);
                         [encoders.render
-                            drawIndexedPrimitives:MTLPrimitiveTypeTriangle
+                            drawIndexedPrimitives:lastRenderPipeline->GetMTLPrimitiveTopology()
                             indexCount:draw->indexCount
                             indexType:indexType
                             indexBuffer:indexBuffer

src/backend/metal/RenderPipelineMTL.h

@@ -27,9 +27,12 @@ namespace metal {
             RenderPipeline(RenderPipelineBuilder* builder);
             ~RenderPipeline();
 
+            MTLPrimitiveType GetMTLPrimitiveTopology() const;
+
             void Encode(id<MTLRenderCommandEncoder> encoder);
 
         private:
+            MTLPrimitiveType mtlPrimitiveTopology;
             id<MTLRenderPipelineState> mtlRenderPipelineState = nil;
     };
 

src/backend/metal/RenderPipelineMTL.mm

@@ -23,8 +23,25 @@
 namespace backend {
 namespace metal {
 
+    namespace {
+        MTLPrimitiveType MTLPrimitiveTopology(nxt::PrimitiveTopology primitiveTopology) {
+            switch (primitiveTopology) {
+                case nxt::PrimitiveTopology::Point:
+                    return MTLPrimitiveTypePoint;
+                case nxt::PrimitiveTopology::Line:
+                    return MTLPrimitiveTypeLine;
+                case nxt::PrimitiveTopology::LineStrip:
+                    return MTLPrimitiveTypeLineStrip;
+                case nxt::PrimitiveTopology::Triangle:
+                    return MTLPrimitiveTypeTriangle;
+                case nxt::PrimitiveTopology::TriangleStrip:
+                    return MTLPrimitiveTypeTriangleStrip;
+            }
+        }
+    }
+
     RenderPipeline::RenderPipeline(RenderPipelineBuilder* builder)
-        : RenderPipelineBase(builder) {
+        : RenderPipelineBase(builder), mtlPrimitiveTopology(MTLPrimitiveTopology(GetPrimitiveTopology())) {
 
         auto mtlDevice = ToBackend(builder->GetDevice())->GetMTLDevice();
 
@@ -73,6 +90,10 @@ namespace metal {
         [mtlRenderPipelineState release];
     }
 
+    MTLPrimitiveType RenderPipeline::GetMTLPrimitiveTopology() const {
+        return mtlPrimitiveTopology;
+    }
+
     void RenderPipeline::Encode(id<MTLRenderCommandEncoder> encoder) {
         [encoder setRenderPipelineState:mtlRenderPipelineState];
     }

src/backend/opengl/CommandBufferGL.cpp

@@ -236,11 +236,11 @@ namespace opengl {
                     {
                         DrawArraysCmd* draw = commands.NextCommand<DrawArraysCmd>();
                         if (draw->firstInstance > 0) {
-                            glDrawArraysInstancedBaseInstance(GL_TRIANGLES,
+                            glDrawArraysInstancedBaseInstance(lastRenderPipeline->GetGLPrimitiveTopology(),
                                 draw->firstVertex, draw->vertexCount, draw->instanceCount, draw->firstInstance);
                         } else {
                             // This branch is only needed on OpenGL < 4.2
-                            glDrawArraysInstanced(GL_TRIANGLES,
+                            glDrawArraysInstanced(lastRenderPipeline->GetGLPrimitiveTopology(),
                                 draw->firstVertex, draw->vertexCount, draw->instanceCount);
                         }
                     }
@@ -253,13 +253,13 @@ namespace opengl {
                         GLenum formatType = IndexFormatType(indexBufferFormat);
 
                         if (draw->firstInstance > 0) {
-                            glDrawElementsInstancedBaseInstance(GL_TRIANGLES,
+                            glDrawElementsInstancedBaseInstance(lastRenderPipeline->GetGLPrimitiveTopology(),
                                 draw->indexCount, formatType,
                                 reinterpret_cast<void*>(draw->firstIndex * formatSize + indexBufferOffset),
                                 draw->instanceCount, draw->firstInstance);
                         } else {
                             // This branch is only needed on OpenGL < 4.2
-                            glDrawElementsInstanced(GL_TRIANGLES,
+                            glDrawElementsInstanced(lastRenderPipeline->GetGLPrimitiveTopology(),
                                 draw->indexCount, formatType,
                                 reinterpret_cast<void*>(draw->firstIndex * formatSize + indexBufferOffset),
                                 draw->instanceCount);

src/backend/opengl/RenderPipelineGL.cpp

@@ -21,8 +21,32 @@
 namespace backend {
 namespace opengl {
 
+    namespace {
+        GLenum GLPrimitiveTopology(nxt::PrimitiveTopology primitiveTopology) {
+            switch (primitiveTopology) {
+                case nxt::PrimitiveTopology::Point:
+                    return GL_POINTS;
+                case nxt::PrimitiveTopology::Line:
+                    return GL_LINES;
+                case nxt::PrimitiveTopology::LineStrip:
+                    return GL_LINE_STRIP;
+                case nxt::PrimitiveTopology::Triangle:
+                    return GL_TRIANGLES;
+                case nxt::PrimitiveTopology::TriangleStrip:
+                    return GL_TRIANGLE_STRIP;
+                default:
+                    UNREACHABLE();
+            }
+        }
+    }
+
     RenderPipeline::RenderPipeline(RenderPipelineBuilder* builder)
-        : RenderPipelineBase(builder), PipelineGL(this, builder) {
+        : RenderPipelineBase(builder), PipelineGL(this, builder),
+          glPrimitiveTopology(GLPrimitiveTopology(GetPrimitiveTopology())) {
+    }
+
+    GLenum RenderPipeline::GetGLPrimitiveTopology() const {
+        return glPrimitiveTopology;
     }
 
     void RenderPipeline::ApplyNow(PersistentPipelineState &persistentPipelineState) {

src/backend/opengl/RenderPipelineGL.h

@@ -32,7 +32,12 @@ namespace opengl {
         public:
             RenderPipeline(RenderPipelineBuilder* builder);
 
+            GLenum GetGLPrimitiveTopology() const;
+
             void ApplyNow(PersistentPipelineState &persistentPipelineState);
+
+        private:
+            GLenum glPrimitiveTopology;
     };
 
 }