added support for glMinSampleShading

src/gpu/vk/GrVkPipeline.cpp

 /*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
 #include "GrVkPipeline.h"
 
 #include "GrGeometryProcessor.h"
@@ skipping 185 matching lines @@
 
     viewportInfo->viewportCount = 1;
     viewportInfo->pViewports = nullptr; // This is set dynamically
 
     viewportInfo->scissorCount = 1;
     viewportInfo->pScissors = nullptr; // This is set dynamically
 
     SkASSERT(viewportInfo->viewportCount == viewportInfo->scissorCount);
 }
 
-void setup_multisample_state(const GrPipeline& pipeline,
+void setup_multisample_state(const GrPipeline& pipeline, 
+                             const GrPrimitiveProcessor& primProc,
+                             const GrCaps* caps,
                              VkPipelineMultisampleStateCreateInfo* multisampleInfo) {
     memset(multisampleInfo, 0, sizeof(VkPipelineMultisampleStateCreateInfo));
     multisampleInfo->sType = VK_STRUCTURE_TYPE_PIPELINE_MULTISAMPLE_STATE_CREATE_INFO;
     multisampleInfo->pNext = nullptr;
     multisampleInfo->flags = 0;
     int numSamples = pipeline.getRenderTarget()->numColorSamples();
     SkAssertResult(GrSampleCountToVkSampleCount(numSamples,
                    &multisampleInfo->rasterizationSamples));
-    multisampleInfo->sampleShadingEnable = VK_FALSE;
-    multisampleInfo->minSampleShading = 0;
+    float sampleShading = primProc.getSampleShading();
+    SkASSERT(sampleShading == 0.0f || caps->sampleShadingSupport());
+    multisampleInfo->sampleShadingEnable = sampleShading > 0.0f;
+    multisampleInfo->minSampleShading = sampleShading;
     multisampleInfo->pSampleMask = nullptr;
     multisampleInfo->alphaToCoverageEnable = VK_FALSE;
     multisampleInfo->alphaToOneEnable = VK_FALSE;
 }
 
 static VkBlendFactor blend_coeff_to_vk_blend(GrBlendCoeff coeff) {
     static const VkBlendFactor gTable[] = {
         VK_BLEND_FACTOR_ZERO,                      // kZero_GrBlendCoeff
         VK_BLEND_FACTOR_ONE,                       // kOne_GrBlendCoeff
         VK_BLEND_FACTOR_SRC_COLOR,                 // kSC_GrBlendCoeff
@@ skipping 193 matching lines @@
 
     VkPipelineDepthStencilStateCreateInfo depthStencilInfo;
     setup_depth_stencil_state(gpu, pipeline.getStencil(), &depthStencilInfo);
 
     GrRenderTarget* rt = pipeline.getRenderTarget();
     GrVkRenderTarget* vkRT = static_cast<GrVkRenderTarget*>(rt);
     VkPipelineViewportStateCreateInfo viewportInfo;
     setup_viewport_scissor_state(gpu, pipeline, vkRT, &viewportInfo);
 
     VkPipelineMultisampleStateCreateInfo multisampleInfo;
-    setup_multisample_state(pipeline, &multisampleInfo);
+    setup_multisample_state(pipeline, primProc, gpu->caps(), &multisampleInfo);
 
     // We will only have one color attachment per pipeline.
     VkPipelineColorBlendAttachmentState attachmentStates[1];
     VkPipelineColorBlendStateCreateInfo colorBlendInfo;
     setup_color_blend_state(gpu, pipeline, &colorBlendInfo, attachmentStates);
 
     VkPipelineRasterizationStateCreateInfo rasterInfo;
     setup_raster_state(gpu, pipeline, &rasterInfo);
 
     VkDynamicState dynamicStates[3];
@@ skipping 103 matching lines @@
 }
 
 void GrVkPipeline::SetDynamicState(GrVkGpu* gpu,
                                    GrVkCommandBuffer* cmdBuffer,
                                    const GrPipeline& pipeline) {
     const GrRenderTarget& target = *pipeline.getRenderTarget();
     set_dynamic_scissor_state(gpu, cmdBuffer, pipeline, target);
     set_dynamic_viewport_state(gpu, cmdBuffer, target);
     set_dynamic_blend_constant_state(gpu, cmdBuffer, pipeline);
 }