Added wide gamut colors to offscreen buffers (flutter/engine#39482)

* Added wide gamut support for offscreen buffers.

* bdero

engine/src/flutter/impeller/renderer/backend/gles/texture_gles.cc

@@ -124,6 +124,7 @@ struct TexImage2DData {
       case PixelFormat::kR8G8UNormInt:
       case PixelFormat::kB10G10R10XRSRGB:
       case PixelFormat::kB10G10R10XR:
+      case PixelFormat::kB10G10R10A10XR:
         return;
     }
     is_valid_ = true;
@@ -171,6 +172,7 @@ struct TexImage2DData {
       case PixelFormat::kR8G8UNormInt:
       case PixelFormat::kB10G10R10XRSRGB:
       case PixelFormat::kB10G10R10XR:
+      case PixelFormat::kB10G10R10A10XR:
         return;
     }
     is_valid_ = true;
@@ -318,6 +320,7 @@ static std::optional<GLenum> ToRenderBufferFormat(PixelFormat format) {
     case PixelFormat::kB8G8R8A8UNormIntSRGB:
     case PixelFormat::kB10G10R10XRSRGB:
     case PixelFormat::kB10G10R10XR:
+    case PixelFormat::kB10G10R10A10XR:
       return std::nullopt;
   }
   FML_UNREACHABLE();

engine/src/flutter/impeller/renderer/backend/metal/formats_mtl.h

@@ -41,6 +41,8 @@ constexpr PixelFormat FromMTLPixelFormat(MTLPixelFormat format) {
       return PixelFormat::kB10G10R10XRSRGB;
     case MTLPixelFormatBGR10_XR:
       return PixelFormat::kB10G10R10XR;
+    case MTLPixelFormatBGRA10_XR:
+      return PixelFormat::kB10G10R10A10XR;
     default:
       return PixelFormat::kUnknown;
   }
@@ -56,6 +58,10 @@ MTLPixelFormat SafeMTLPixelFormatBGR10_XR_sRGB();
 /// Returns PixelFormat::kUnknown if MTLPixelFormatBGR10_XR isn't supported.
 MTLPixelFormat SafeMTLPixelFormatBGR10_XR();
 
+/// Safe accessor for MTLPixelFormatBGRA10_XR.
+/// Returns PixelFormat::kUnknown if MTLPixelFormatBGR10_XR isn't supported.
+MTLPixelFormat SafeMTLPixelFormatBGRA10_XR();
+
 constexpr MTLPixelFormat ToMTLPixelFormat(PixelFormat format) {
   switch (format) {
     case PixelFormat::kUnknown:
@@ -86,6 +92,8 @@ constexpr MTLPixelFormat ToMTLPixelFormat(PixelFormat format) {
       return SafeMTLPixelFormatBGR10_XR_sRGB();
     case PixelFormat::kB10G10R10XR:
       return SafeMTLPixelFormatBGR10_XR();
+    case PixelFormat::kB10G10R10A10XR:
+      return SafeMTLPixelFormatBGRA10_XR();
   }
   return MTLPixelFormatInvalid;
 };

engine/src/flutter/impeller/renderer/backend/metal/formats_mtl.mm

@@ -120,4 +120,12 @@ MTLPixelFormat SafeMTLPixelFormatBGR10_XR() {
   }
 }
 
+MTLPixelFormat SafeMTLPixelFormatBGRA10_XR() {
+  if (@available(iOS 10, macOS 11.0, *)) {
+    return MTLPixelFormatBGRA10_XR;
+  } else {
+    return MTLPixelFormatInvalid;
+  }
+}
+
 }  // namespace impeller

engine/src/flutter/impeller/renderer/backend/vulkan/formats_vk.h

@@ -138,6 +138,7 @@ constexpr vk::Format ToVKImageFormat(PixelFormat format) {
   switch (format) {
     case PixelFormat::kUnknown:
     case PixelFormat::kB10G10R10XR:
+    case PixelFormat::kB10G10R10A10XR:
     case PixelFormat::kB10G10R10XRSRGB:
       return vk::Format::eUndefined;
     case PixelFormat::kA8UNormInt:

engine/src/flutter/impeller/renderer/formats.h

@@ -91,6 +91,7 @@ enum class PixelFormat {
   kR16G16B16A16Float,
   kB10G10R10XR,
   kB10G10R10XRSRGB,
+  kB10G10R10A10XR,
   // Depth and stencil formats.
   kS8UInt,
   kD32FloatS8UInt,
@@ -296,6 +297,7 @@ constexpr size_t BytesPerPixelForPixelFormat(PixelFormat format) {
     case PixelFormat::kD32FloatS8UInt:
       return 5u;
     case PixelFormat::kR16G16B16A16Float:
+    case PixelFormat::kB10G10R10A10XR:
       return 8u;
     case PixelFormat::kR32G32B32A32Float:
       return 16u;

engine/src/flutter/impeller/renderer/render_target.cc

@@ -202,10 +202,10 @@ RenderTarget RenderTarget::CreateOffscreen(
   }
 
   RenderTarget target;
-
+  PixelFormat pixel_format = context.GetColorAttachmentPixelFormat();
   TextureDescriptor color_tex0;
   color_tex0.storage_mode = color_attachment_config.storage_mode;
-  color_tex0.format = context.GetColorAttachmentPixelFormat();
+  color_tex0.format = pixel_format;
   color_tex0.size = size;
   color_tex0.usage = static_cast<uint64_t>(TextureUsage::kRenderTarget) |
                      static_cast<uint64_t>(TextureUsage::kShaderRead);
@@ -260,6 +260,7 @@ RenderTarget RenderTarget::CreateOffscreenMSAA(
   }
 
   RenderTarget target;
+  PixelFormat pixel_format = context.GetColorAttachmentPixelFormat();
 
   // Create MSAA color texture.
 
@@ -267,7 +268,7 @@ RenderTarget RenderTarget::CreateOffscreenMSAA(
   color0_tex_desc.storage_mode = color_attachment_config.storage_mode;
   color0_tex_desc.type = TextureType::kTexture2DMultisample;
   color0_tex_desc.sample_count = SampleCount::kCount4;
-  color0_tex_desc.format = context.GetColorAttachmentPixelFormat();
+  color0_tex_desc.format = pixel_format;
   color0_tex_desc.size = size;
   color0_tex_desc.usage = static_cast<uint64_t>(TextureUsage::kRenderTarget);
 
@@ -285,7 +286,7 @@ RenderTarget RenderTarget::CreateOffscreenMSAA(
   TextureDescriptor color0_resolve_tex_desc;
   color0_resolve_tex_desc.storage_mode =
       color_attachment_config.resolve_storage_mode;
-  color0_resolve_tex_desc.format = context.GetColorAttachmentPixelFormat();
+  color0_resolve_tex_desc.format = pixel_format;
   color0_resolve_tex_desc.size = size;
   color0_resolve_tex_desc.usage =
       static_cast<uint64_t>(TextureUsage::kRenderTarget) |

engine/src/flutter/shell/platform/darwin/ios/framework/Source/FlutterView.mm

@@ -87,7 +87,9 @@ static BOOL IsWideGamutSupported() {
       layer.colorspace = srgb;
       CFRelease(srgb);
       if (self.opaque) {
-        layer.pixelFormat = MTLPixelFormatBGR10_XR;
+        // TODO(https://github.com/flutter/flutter/issues/120641): Switch to
+        // MTLPixelFormatBGR10_XR to save memory.
+        layer.pixelFormat = MTLPixelFormatBGRA10_XR;
       } else {
         layer.pixelFormat = MTLPixelFormatBGRA10_XR;
       }