Tweaks to Metal pipeline state.

Bug: skia:8243
Change-Id: If2a0d38eedb197175b69d3c3b8422e4dfbfa8e02
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/201610
Reviewed-by: Greg Daniel <[email protected]>
Commit-Queue: Jim Van Verth <[email protected]>

Author: jvanverth

src/gpu/mtl/GrMtlGpuCommandBuffer.mm

@@ -148,12 +148,16 @@
     SkASSERT(fActiveRenderCmdEncoder);
     // TODO: can we set this once somewhere at the beginning of the draw?
     [fActiveRenderCmdEncoder setFrontFacingWinding:MTLWindingCounterClockwise];
+    // Strictly speaking we shouldn't have to set this, as the default viewport is the size of
+    // the drawable used to generate the renderCommandEncoder -- but just in case.
+    MTLViewport viewport = { 0.0, 0.0,
+                             (double) fRenderTarget->width(), (double) fRenderTarget->height(),
+                             0.0, 1.0 };
+    [fActiveRenderCmdEncoder setViewport:viewport];
 
     [fActiveRenderCmdEncoder setRenderPipelineState:pipelineState->mtlPipelineState()];
-    pipelineState->bind(fActiveRenderCmdEncoder);
-    pipelineState->setBlendConstants(fActiveRenderCmdEncoder, fRenderTarget->config(),
-                                     pipeline.getXferProcessor());
-    pipelineState->setDepthStencilState(fActiveRenderCmdEncoder);
+    pipelineState->setDrawState(fActiveRenderCmdEncoder, fRenderTarget->config(),
+                                pipeline.getXferProcessor());
 
     bool dynamicScissor =
             pipeline.isScissorEnabled() && dynamicStateArrays && dynamicStateArrays->fScissorRects;
@@ -182,10 +186,8 @@
             }
 
             [fActiveRenderCmdEncoder setRenderPipelineState:pipelineState->mtlPipelineState()];
-            pipelineState->bind(fActiveRenderCmdEncoder);
-            pipelineState->setBlendConstants(fActiveRenderCmdEncoder, fRenderTarget->config(),
-                                             pipeline.getXferProcessor());
-            pipelineState->setDepthStencilState(fActiveRenderCmdEncoder);
+            pipelineState->setDrawState(fActiveRenderCmdEncoder, fRenderTarget->config(),
+                                        pipeline.getXferProcessor());
         }
 
         if (dynamicScissor) {

src/gpu/mtl/GrMtlPipelineState.h

@@ -51,11 +51,7 @@ class GrMtlPipelineState {
                  const GrPrimitiveProcessor& primPRoc, const GrPipeline& pipeline,
                  const GrTextureProxy* const primProcTextures[]);
 
-    void bind(id<MTLRenderCommandEncoder>);
-
-    void setBlendConstants(id<MTLRenderCommandEncoder>, GrPixelConfig, const GrXferProcessor&);
-
-    void setDepthStencilState(id<MTLRenderCommandEncoder> renderCmdEncoder);
+    void setDrawState(id<MTLRenderCommandEncoder>, GrPixelConfig, const GrXferProcessor&);
 
     static void SetDynamicScissorRectState(id<MTLRenderCommandEncoder> renderCmdEncoder,
                                            const GrRenderTarget* renderTarget,
@@ -101,6 +97,12 @@ class GrMtlPipelineState {
 
     void setRenderTargetState(const GrRenderTarget*, GrSurfaceOrigin);
 
+    void bind(id<MTLRenderCommandEncoder>);
+
+    void setBlendConstants(id<MTLRenderCommandEncoder>, GrPixelConfig, const GrXferProcessor&);
+
+    void setDepthStencilState(id<MTLRenderCommandEncoder> renderCmdEncoder);
+
     struct SamplerBindings {
         id<MTLSamplerState> fSampler;
         id<MTLTexture> fTexture;

src/gpu/mtl/GrMtlPipelineState.mm

@@ -118,6 +118,13 @@
     }
 }
 
+void GrMtlPipelineState::setDrawState(id<MTLRenderCommandEncoder> renderCmdEncoder,
+                                      GrPixelConfig config, const GrXferProcessor& xferProcessor) {
+    this->bind(renderCmdEncoder);
+    this->setBlendConstants(renderCmdEncoder, config, xferProcessor);
+    this->setDepthStencilState(renderCmdEncoder);
+}
+
 void GrMtlPipelineState::bind(id<MTLRenderCommandEncoder> renderCmdEncoder) {
     if (fGeometryUniformBuffer) {
         [renderCmdEncoder setVertexBuffer: fGeometryUniformBuffer->mtlBuffer()