[Impeller] Enable SSBOs in the Vulkan backend. (#40908)

[Impeller] Enable SSBOs in the Vulkan backend.

Author: chinmaygarde

impeller/compiler/code_gen_template.h

@@ -162,14 +162,14 @@ std::move({{ arg.argument_name }}){% if not loop.is_last %}, {% endif %}
 {% for buffer in buffers %}
     DescriptorSetLayout{
       {{buffer.binding}}, // binding = {{buffer.binding}}
-      DescriptorType::kUniformBuffer, // descriptor_type = Uniform Buffer
+      {{buffer.descriptor_type}}, // descriptor_type = {{buffer.descriptor_type}}
       {{to_shader_stage(shader_stage)}}, // shader_stage = {{to_shader_stage(shader_stage)}}
     },
 {% endfor %}
 {% for sampled_image in sampled_images %}
     DescriptorSetLayout{
       {{sampled_image.binding}}, // binding = {{sampled_image.binding}}
-      DescriptorType::kSampledImage, // descriptor_type = Sampled Image
+      {{sampled_image.descriptor_type}}, // descriptor_type = {{sampled_image.descriptor_type}}
       {{to_shader_stage(shader_stage)}}, // shader_stage = {{to_shader_stage(shader_stage)}}
     },
 {% endfor %}

impeller/compiler/reflector.cc

@@ -205,7 +205,8 @@ std::optional<nlohmann::json> Reflector::GenerateTemplateArguments() const {
     if (auto uniform_buffers_json =
             ReflectResources(shader_resources.uniform_buffers);
         uniform_buffers_json.has_value()) {
-      for (const auto& uniform_buffer : uniform_buffers_json.value()) {
+      for (auto uniform_buffer : uniform_buffers_json.value()) {
+        uniform_buffer["descriptor_type"] = "DescriptorType::kUniformBuffer";
         buffers.emplace_back(std::move(uniform_buffer));
       }
     } else {
@@ -214,7 +215,8 @@ std::optional<nlohmann::json> Reflector::GenerateTemplateArguments() const {
     if (auto storage_buffers_json =
             ReflectResources(shader_resources.storage_buffers);
         storage_buffers_json.has_value()) {
-      for (const auto& uniform_buffer : storage_buffers_json.value()) {
+      for (auto uniform_buffer : storage_buffers_json.value()) {
+        uniform_buffer["descriptor_type"] = "DescriptorType::kStorageBuffer";
         buffers.emplace_back(std::move(uniform_buffer));
       }
     } else {
@@ -244,12 +246,15 @@ std::optional<nlohmann::json> Reflector::GenerateTemplateArguments() const {
     }
     auto& sampled_images = root["sampled_images"] = nlohmann::json::array_t{};
     for (auto value : combined_sampled_images.value()) {
+      value["descriptor_type"] = "DescriptorType::kSampledImage";
       sampled_images.emplace_back(std::move(value));
     }
     for (auto value : images.value()) {
+      value["descriptor_type"] = "DescriptorType::kImage";
       sampled_images.emplace_back(std::move(value));
     }
     for (auto value : samplers.value()) {
+      value["descriptor_type"] = "DescriptorType::kSampledSampler";
       sampled_images.emplace_back(std::move(value));
     }
   }

impeller/compiler/spirv_compiler.cc

@@ -208,14 +208,22 @@ static void SetDefaultLimitations(shaderc::CompileOptions& compiler_opts) {
 }
 
 static void SetBindingBaseOffset(shaderc::CompileOptions& options) {
-  constexpr uint32_t kFragBindingBase = 128;
-  constexpr size_t kNumUniformKinds =
-      static_cast<int>(shaderc_uniform_kind::shaderc_uniform_kind_buffer) + 1;
-  for (size_t uniform_kind = 0; uniform_kind < kNumUniformKinds;
-       uniform_kind++) {
+  constexpr uint32_t kBindingBaseOffset = 64;
+  static const shaderc_uniform_kind kUniformKinds[] = {
+      shaderc_uniform_kind::shaderc_uniform_kind_sampler,
+      shaderc_uniform_kind::shaderc_uniform_kind_texture,
+      shaderc_uniform_kind::shaderc_uniform_kind_image,
+      shaderc_uniform_kind::shaderc_uniform_kind_buffer,          // UBOs
+      shaderc_uniform_kind::shaderc_uniform_kind_storage_buffer,  // SSBOs
+  };
+
+  for (size_t i = 0u; i < sizeof(kUniformKinds) / sizeof(shaderc_uniform_kind);
+       i++) {
     options.SetBindingBaseForStage(
-        ToShaderCShaderKind(SourceType::kFragmentShader),
-        static_cast<shaderc_uniform_kind>(uniform_kind), kFragBindingBase);
+        shaderc_shader_kind::shaderc_fragment_shader,  //
+        kUniformKinds[i],                              //
+        kBindingBaseOffset                             //
+    );
   }
 }
 

impeller/core/shader_types.h

@@ -125,8 +125,11 @@ struct SampledImageSlot {
 };
 
 enum class DescriptorType {
-  kSampledImage,
   kUniformBuffer,
+  kStorageBuffer,
+  kSampledImage,
+  kImage,
+  kSampler,
 };
 
 struct DescriptorSetLayout {

impeller/renderer/backend/vulkan/capabilities_vk.cc

@@ -310,7 +310,7 @@ bool CapabilitiesVK::SupportsOffscreenMSAA() const {
 
 // |Capabilities|
 bool CapabilitiesVK::SupportsSSBO() const {
-  return false;
+  return true;
 }
 
 // |Capabilities|

impeller/renderer/backend/vulkan/debug_report_vk.cc

@@ -183,7 +183,7 @@ DebugReportVK::Result DebugReportVK::OnDebugCallback(
     VALIDATION_LOG << stream.str();
   }
 
-  return Result::kAbort;
+  return Result::kContinue;
 }
 
 }  // namespace impeller

impeller/renderer/backend/vulkan/descriptor_pool_vk.cc

@@ -19,6 +19,9 @@ static vk::UniqueDescriptorPool CreatePool(const vk::Device& device,
   std::vector<vk::DescriptorPoolSize> pools = {
       {vk::DescriptorType::eCombinedImageSampler, pool_count},
       {vk::DescriptorType::eUniformBuffer, pool_count},
+      {vk::DescriptorType::eStorageBuffer, pool_count},
+      {vk::DescriptorType::eSampledImage, pool_count},
+      {vk::DescriptorType::eSampler, pool_count},
   };
 
   vk::DescriptorPoolCreateInfo pool_info;

impeller/renderer/backend/vulkan/formats_vk.h

@@ -279,6 +279,15 @@ constexpr vk::DescriptorSetLayoutBinding ToVKDescriptorSetLayoutBinding(
     case DescriptorType::kUniformBuffer:
       desc_type = vk::DescriptorType::eUniformBuffer;
       break;
+    case DescriptorType::kStorageBuffer:
+      desc_type = vk::DescriptorType::eStorageBuffer;
+      break;
+    case DescriptorType::kImage:
+      desc_type = vk::DescriptorType::eSampledImage;
+      break;
+    case DescriptorType::kSampler:
+      desc_type = vk::DescriptorType::eSampler;
+      break;
   }
   binding.descriptorType = desc_type;
   binding.stageFlags = ToVkShaderStage(layout.shader_stage);