Switch uniforms to be descriptor set 0 in Vulkan

src/gpu/vk/GrVkPipelineStateBuilder.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 "vk/GrVkPipelineStateBuilder.h"
 
 #include "vk/GrVkGpu.h"
@@ skipping 152 matching lines @@
     VkShaderModule fragShaderModule;
 
     uint32_t numSamplers = fSamplerUniforms.count();
 
     SkAutoTDeleteArray<VkDescriptorSetLayoutBinding> dsSamplerBindings(
                                                      new VkDescriptorSetLayoutBinding[numSamplers]);
     for (uint32_t i = 0; i < numSamplers; ++i) {
         UniformHandle uniHandle = fSamplerUniforms[i];
         GrVkUniformHandler::UniformInfo uniformInfo = fUniformHandler.getUniformInfo(uniHandle);
         SkASSERT(kSampler2D_GrSLType == uniformInfo.fVariable.getType());
-        SkASSERT(0 == uniformInfo.fSetNumber);
+        SkASSERT(GrVkUniformHandler::kSamplerDescSet == uniformInfo.fSetNumber);
         SkASSERT(uniformInfo.fBinding == i);
         dsSamplerBindings[i].binding = uniformInfo.fBinding;
         dsSamplerBindings[i].descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER;
         dsSamplerBindings[i].descriptorCount = 1;
         dsSamplerBindings[i].stageFlags = visibility_to_vk_stage_flags(uniformInfo.fVisibility);
         dsSamplerBindings[i].pImmutableSamplers = nullptr;
     }
 
     VkDescriptorSetLayoutCreateInfo dsSamplerLayoutCreateInfo;
     memset(&dsSamplerLayoutCreateInfo, 0, sizeof(VkDescriptorSetLayoutCreateInfo));
@@ skipping 12 matching lines @@
                                                   nullptr,
                                                   &dsLayout[GrVkUniformHandler::kSamplerDescSet]));
 
     // Create Uniform Buffer Descriptor
     // We always attach uniform buffers to descriptor set 1. The vertex uniform buffer will have
     // binding 0 and the fragment binding 1.
     VkDescriptorSetLayoutBinding dsUniBindings[2];
     memset(&dsUniBindings, 0, 2 * sizeof(VkDescriptorSetLayoutBinding));
     dsUniBindings[0].binding = GrVkUniformHandler::kVertexBinding;
     dsUniBindings[0].descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER;
-    dsUniBindings[0].descriptorCount = fUniformHandler.hasVertexUniforms() ? 1 : 0;
+    dsUniBindings[0].descriptorCount = 1;

[egdaniel, 2016/04/06 20:22:48]

This is needed so that the layout for all our uniforms stays the same (and we
don't spend time invaliding unnecessary descriptor sets. We don't actually end
up making the extra uniform buffers, just saying the layout allows them. 

     dsUniBindings[0].stageFlags = VK_SHADER_STAGE_VERTEX_BIT;
     dsUniBindings[0].pImmutableSamplers = nullptr;
     dsUniBindings[1].binding = GrVkUniformHandler::kFragBinding;
     dsUniBindings[1].descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER;
-    dsUniBindings[1].descriptorCount = fUniformHandler.hasFragmentUniforms() ? 1 : 0;
+    dsUniBindings[1].descriptorCount = 1;
     dsUniBindings[1].stageFlags = VK_SHADER_STAGE_FRAGMENT_BIT;
     dsUniBindings[1].pImmutableSamplers = nullptr;
 
     VkDescriptorSetLayoutCreateInfo dsUniformLayoutCreateInfo;
     memset(&dsUniformLayoutCreateInfo, 0, sizeof(VkDescriptorSetLayoutCreateInfo));
     dsUniformLayoutCreateInfo.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO;
     dsUniformLayoutCreateInfo.pNext = nullptr;
     dsUniformLayoutCreateInfo.flags = 0;
     dsUniformLayoutCreateInfo.bindingCount = 2;
     dsUniformLayoutCreateInfo.pBindings = dsUniBindings;
@@ skipping 72 matching lines @@
                                  dsLayout,
                                  fUniformHandles,
                                  fUniformHandler.fUniforms,
                                  fUniformHandler.fCurrentVertexUBOOffset,
                                  fUniformHandler.fCurrentFragmentUBOOffset,
                                  numSamplers,
                                  fGeometryProcessor,
                                  fXferProcessor,
                                  fFragmentProcessors);
 }