[Impeller] Device default attachment pixel formats

impeller/entity/contents/content_context.cc

@@ -28,7 +28,13 @@ void ContentContextOptions::ApplyToPipelineDescriptor(
   desc.SetSampleCount(sample_count);
 
   ColorAttachmentDescriptor color0 = *desc.GetColorAttachmentDescriptor(0u);
-  color0.format = color_attachment_pixel_format;
+  if (!color_attachment_pixel_format.has_value()) {
+    VALIDATION_LOG << "Color attachment pixel format must be set.";
+    color0.format = PixelFormat::kB8G8R8A8UNormInt;
+  } else {
+    color0.format = *color_attachment_pixel_format;
+  }
+  color0.format = *color_attachment_pixel_format;
   color0.alpha_blend_op = BlendOperation::kAdd;
   color0.color_blend_op = BlendOperation::kAdd;
 
@@ -145,7 +151,9 @@ static std::unique_ptr<PipelineT> CreateDefaultPipeline(
     return nullptr;
   }
   // Apply default ContentContextOptions to the descriptor.
-  ContentContextOptions{}.ApplyToPipelineDescriptor(*desc);
+  const auto default_color_fmt = context.GetColorAttachmentPixelFormat();
+  ContentContextOptions{.color_attachment_pixel_format = default_color_fmt}
+      .ApplyToPipelineDescriptor(*desc);
   return std::make_unique<PipelineT>(context, desc);
 }
 

impeller/entity/contents/content_context.h

@@ -5,6 +5,7 @@
 #pragma once
 
 #include <memory>
+#include <optional>
 #include <unordered_map>
 
 #include "flutter/fml/hash_combine.h"
@@ -265,7 +266,7 @@ struct ContentContextOptions {
   CompareFunction stencil_compare = CompareFunction::kEqual;
   StencilOperation stencil_operation = StencilOperation::kKeep;
   PrimitiveType primitive_type = PrimitiveType::kTriangle;
-  PixelFormat color_attachment_pixel_format = PixelFormat::kDefaultColor;
+  std::optional<PixelFormat> color_attachment_pixel_format;
   bool has_stencil_attachment = true;
 
   struct Hash {

impeller/entity/contents/runtime_effect_contents.cc

@@ -102,6 +102,11 @@ bool RuntimeEffectContents::Render(const ContentContext& renderer,
   /// Get or create runtime stage pipeline.
   ///
 
+  const auto& device_capabilities = context->GetDeviceCapabilities();
+  const auto color_attachment_format = context->GetColorAttachmentPixelFormat();
+  const auto stencil_attachment_format =
+      device_capabilities.GetDefaultStencilFormat();
+
   using VS = RuntimeEffectVertexShader;
   PipelineDescriptor desc;
   desc.SetLabel("Runtime Stage");
@@ -115,9 +120,9 @@ bool RuntimeEffectContents::Render(const ContentContext& renderer,
   }
   desc.SetVertexDescriptor(std::move(vertex_descriptor));
   desc.SetColorAttachmentDescriptor(
-      0u, {.format = PixelFormat::kDefaultColor, .blending_enabled = true});
+      0u, {.format = color_attachment_format, .blending_enabled = true});
   desc.SetStencilAttachmentDescriptors({});
-  desc.SetStencilPixelFormat(PixelFormat::kDefaultStencil);
+  desc.SetStencilPixelFormat(stencil_attachment_format);
 
   auto options = OptionsFromPassAndEntity(pass, entity);
   if (geometry_result.prevent_overdraw) {

impeller/playground/backend/metal/playground_impl_mtl.mm

@@ -75,7 +75,8 @@
   data_->metal_layer = [CAMetalLayer layer];
   data_->metal_layer.device = ContextMTL::Cast(*context).GetMTLDevice();
   // This pixel format is one of the documented supported formats.
-  data_->metal_layer.pixelFormat = ToMTLPixelFormat(PixelFormat::kDefaultColor);
+  const auto color_fmt = context->GetColorAttachmentPixelFormat();
+  data_->metal_layer.pixelFormat = ToMTLPixelFormat(color_fmt);
   data_->metal_layer.framebufferOnly = NO;
   cocoa_window.contentView.layer = data_->metal_layer;
   cocoa_window.contentView.wantsLayer = YES;

impeller/renderer/backend/gles/context_gles.cc

@@ -71,11 +71,14 @@ ContextGLES::ContextGLES(std::unique_ptr<ProcTableGLES> gl,
 
   // Create the device capabilities.
   {
-    device_capabilities_ = DeviceCapabilitiesBuilder()
-                               .SetHasThreadingRestrictions(true)
-                               .SetSupportsOffscreenMSAA(false)
-                               .SetSupportsSSBO(false)
-                               .Build();
+    device_capabilities_ =
+        DeviceCapabilitiesBuilder()
+            .SetHasThreadingRestrictions(true)
+            .SetSupportsOffscreenMSAA(false)
+            .SetSupportsSSBO(false)
+            .SetDefaultColorFormat(PixelFormat::kB8G8R8A8UNormInt)
+            .SetDefaultStencilFormat(PixelFormat::kS8UInt)
+            .Build();
   }
 
   is_valid_ = true;

impeller/renderer/backend/metal/context_mtl.mm

@@ -90,11 +90,14 @@
 #endif
 
   {
-    device_capabilities_ = DeviceCapabilitiesBuilder()
-                               .SetHasThreadingRestrictions(false)
-                               .SetSupportsOffscreenMSAA(true)
-                               .SetSupportsSSBO(true)
-                               .Build();
+    device_capabilities_ =
+        DeviceCapabilitiesBuilder()
+            .SetHasThreadingRestrictions(false)
+            .SetSupportsOffscreenMSAA(true)
+            .SetSupportsSSBO(true)
+            .SetDefaultColorFormat(PixelFormat::kB8G8R8A8UNormInt)
+            .SetDefaultStencilFormat(PixelFormat::kS8UInt)
+            .Build();
   }
 
   is_valid_ = true;

impeller/renderer/backend/metal/surface_mtl.mm

@@ -81,7 +81,8 @@
   stencil0_tex.storage_mode = StorageMode::kDeviceTransient;
   stencil0_tex.type = TextureType::kTexture2DMultisample;
   stencil0_tex.sample_count = SampleCount::kCount4;
-  stencil0_tex.format = PixelFormat::kDefaultStencil;
+  stencil0_tex.format =
+      context->GetDeviceCapabilities().GetDefaultStencilFormat();
   stencil0_tex.size = color0_tex_desc.size;
   stencil0_tex.usage =
       static_cast<TextureUsageMask>(TextureUsage::kRenderTarget);

impeller/renderer/backend/vulkan/context_vk.cc

@@ -499,11 +499,14 @@ ContextVK::ContextVK(
   transfer_queue_ =
       device_->getQueue(transfer_queue->family, transfer_queue->index);
 
-  device_capabilities_ = DeviceCapabilitiesBuilder()
-                             .SetHasThreadingRestrictions(false)
-                             .SetSupportsOffscreenMSAA(true)
-                             .SetSupportsSSBO(false)
-                             .Build();
+  device_capabilities_ =
+      DeviceCapabilitiesBuilder()
+          .SetHasThreadingRestrictions(false)
+          .SetSupportsOffscreenMSAA(true)
+          .SetSupportsSSBO(false)
+          .SetDefaultColorFormat(PixelFormat::kB8G8R8A8UNormInt)
+          .SetDefaultStencilFormat(PixelFormat::kS8UInt)
+          .Build();
 
   is_valid_ = true;
 }

impeller/renderer/context.cc

@@ -15,7 +15,7 @@ std::shared_ptr<GPUTracer> Context::GetGPUTracer() const {
 }
 
 PixelFormat Context::GetColorAttachmentPixelFormat() const {
-  return PixelFormat::kDefaultColor;
+  return GetDeviceCapabilities().GetDefaultColorFormat();
 }
 
 }  // namespace impeller

impeller/renderer/device_capabilities.cc

@@ -8,10 +8,14 @@ namespace impeller {
 
 IDeviceCapabilities::IDeviceCapabilities(bool threading_restrictions,
                                          bool offscreen_msaa,
-                                         bool supports_ssbo)
+                                         bool supports_ssbo,
+                                         PixelFormat default_color_format,
+                                         PixelFormat default_stencil_format)
     : threading_restrictions_(threading_restrictions),
       offscreen_msaa_(offscreen_msaa),
-      supports_ssbo_(supports_ssbo) {}
+      supports_ssbo_(supports_ssbo),
+      default_color_format_(default_color_format),
+      default_stencil_format_(default_stencil_format) {}
 
 IDeviceCapabilities::~IDeviceCapabilities() = default;
 
@@ -27,6 +31,14 @@ bool IDeviceCapabilities::SupportsSSBO() const {
   return supports_ssbo_;
 }
 
+PixelFormat IDeviceCapabilities::GetDefaultColorFormat() const {
+  return default_color_format_;
+}
+
+PixelFormat IDeviceCapabilities::GetDefaultStencilFormat() const {
+  return default_stencil_format_;
+}
+
 DeviceCapabilitiesBuilder::DeviceCapabilitiesBuilder() = default;
 
 DeviceCapabilitiesBuilder::~DeviceCapabilitiesBuilder() = default;
@@ -49,9 +61,27 @@ DeviceCapabilitiesBuilder& DeviceCapabilitiesBuilder::SetSupportsSSBO(
   return *this;
 }
 
+DeviceCapabilitiesBuilder& DeviceCapabilitiesBuilder::SetDefaultColorFormat(
+    PixelFormat value) {
+  default_color_format_ = value;
+  return *this;
+}
+
+DeviceCapabilitiesBuilder& DeviceCapabilitiesBuilder::SetDefaultStencilFormat(
+    PixelFormat value) {
+  default_stencil_format_ = value;
+  return *this;
+}
+
 std::unique_ptr<IDeviceCapabilities> DeviceCapabilitiesBuilder::Build() {
+  FML_CHECK(default_color_format_.has_value())
+      << "Default color format not set";
+  FML_CHECK(default_stencil_format_.has_value())
+      << "Default stencil format not set";
+
   IDeviceCapabilities* capabilities = new IDeviceCapabilities(
-      threading_restrictions_, offscreen_msaa_, supports_ssbo_);
+      threading_restrictions_, offscreen_msaa_, supports_ssbo_,
+      *default_color_format_, *default_stencil_format_);
   return std::unique_ptr<IDeviceCapabilities>(capabilities);
 }
 

impeller/renderer/device_capabilities.h

@@ -7,6 +7,7 @@
 #include <memory>
 
 #include "flutter/fml/macros.h"
+#include "impeller/renderer/formats.h"
 
 namespace impeller {
 
@@ -20,16 +21,24 @@ class IDeviceCapabilities {
 
   bool SupportsSSBO() const;
 
+  PixelFormat GetDefaultColorFormat() const;
+
+  PixelFormat GetDefaultStencilFormat() const;
+
  private:
   IDeviceCapabilities(bool threading_restrictions,
                       bool offscreen_msaa,
-                      bool supports_ssbo);
+                      bool supports_ssbo,
+                      PixelFormat default_color_format,
+                      PixelFormat default_stencil_format);
 
   friend class DeviceCapabilitiesBuilder;
 
   bool threading_restrictions_ = false;
   bool offscreen_msaa_ = false;
   bool supports_ssbo_ = false;
+  PixelFormat default_color_format_;
+  PixelFormat default_stencil_format_;
 
   FML_DISALLOW_COPY_AND_ASSIGN(IDeviceCapabilities);
 };
@@ -46,12 +55,18 @@ class DeviceCapabilitiesBuilder {
 
   DeviceCapabilitiesBuilder& SetSupportsSSBO(bool value);
 
+  DeviceCapabilitiesBuilder& SetDefaultColorFormat(PixelFormat value);
+
+  DeviceCapabilitiesBuilder& SetDefaultStencilFormat(PixelFormat value);
+
   std::unique_ptr<IDeviceCapabilities> Build();
 
  private:
   bool threading_restrictions_ = false;
   bool offscreen_msaa_ = false;
   bool supports_ssbo_ = false;
+  std::optional<PixelFormat> default_color_format_ = std::nullopt;
+  std::optional<PixelFormat> default_stencil_format_ = std::nullopt;
 
   FML_DISALLOW_COPY_AND_ASSIGN(DeviceCapabilitiesBuilder);
 };

impeller/renderer/formats.h

@@ -95,14 +95,6 @@ enum class PixelFormat {
   // Depth and stencil formats.
   kS8UInt,
   kD32FloatS8UInt,
-
-  // Defaults. If you don't know which ones to use, these are usually a safe
-  // bet.
-  //
-  // On Metal, this is a support format for layer drawable and can be used to
-  // specify the format of the resolve texture if needed.
-  kDefaultColor = kB8G8R8A8UNormInt,
-  kDefaultStencil = kS8UInt,
 };
 
 enum class BlendFactor {

impeller/renderer/pipeline_builder.h

@@ -127,7 +127,8 @@ struct PipelineBuilder {
       StencilAttachmentDescriptor stencil0;
       stencil0.stencil_compare = CompareFunction::kEqual;
       desc.SetStencilAttachmentDescriptors(stencil0);
-      desc.SetStencilPixelFormat(PixelFormat::kDefaultStencil);
+      desc.SetStencilPixelFormat(
+          context.GetDeviceCapabilities().GetDefaultStencilFormat());
     }
 
     return true;

impeller/renderer/render_target.cc

@@ -225,7 +225,8 @@ RenderTarget RenderTarget::CreateOffscreen(
   if (stencil_attachment_config.has_value()) {
     TextureDescriptor stencil_tex0;
     stencil_tex0.storage_mode = stencil_attachment_config->storage_mode;
-    stencil_tex0.format = PixelFormat::kDefaultStencil;
+    stencil_tex0.format =
+        context.GetDeviceCapabilities().GetDefaultStencilFormat();
     stencil_tex0.size = size;
     stencil_tex0.usage =
         static_cast<TextureUsageMask>(TextureUsage::kRenderTarget);
@@ -318,7 +319,8 @@ RenderTarget RenderTarget::CreateOffscreenMSAA(
     stencil_tex0.storage_mode = stencil_attachment_config->storage_mode;
     stencil_tex0.type = TextureType::kTexture2DMultisample;
     stencil_tex0.sample_count = SampleCount::kCount4;
-    stencil_tex0.format = PixelFormat::kDefaultStencil;
+    stencil_tex0.format =
+        context.GetDeviceCapabilities().GetDefaultStencilFormat();
     stencil_tex0.size = size;
     stencil_tex0.usage =
         static_cast<TextureUsageMask>(TextureUsage::kRenderTarget);

impeller/runtime_stage/runtime_stage_unittests.cc

@@ -242,12 +242,14 @@ TEST_P(RuntimeStageTest, CanCreatePipelineFromRuntimeStage) {
   ASSERT_TRUE(vertex_descriptor->SetStageInputs(VS::kAllShaderStageInputs));
   desc.SetVertexDescriptor(std::move(vertex_descriptor));
   ColorAttachmentDescriptor color0;
-  color0.format = PixelFormat::kDefaultColor;
+  color0.format = GetContext()->GetColorAttachmentPixelFormat();
   StencilAttachmentDescriptor stencil0;
   stencil0.stencil_compare = CompareFunction::kEqual;
   desc.SetColorAttachmentDescriptor(0u, color0);
   desc.SetStencilAttachmentDescriptors(stencil0);
-  desc.SetStencilPixelFormat(PixelFormat::kDefaultStencil);
+  const auto stencil_fmt =
+      GetContext()->GetDeviceCapabilities().GetDefaultStencilFormat();
+  desc.SetStencilPixelFormat(stencil_fmt);
   auto pipeline = GetContext()->GetPipelineLibrary()->GetPipeline(desc).Get();
   ASSERT_NE(pipeline, nullptr);
 }