From ad4202f1e0a93ecbb57d5c77a982d48232f61e64 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 9 Jul 2024 12:55:08 -0700
Subject: [PATCH 01/37] [Impeller] enable experimental canvas.

---
 common/config.gni                    |  2 +-
 impeller/aiks/experimental_canvas.cc | 24 ++++++++----------------
 2 files changed, 9 insertions(+), 17 deletions(-)

diff --git a/common/config.gni b/common/config.gni
index c587735b5063e..577c83940f84f 100644
--- a/common/config.gni
+++ b/common/config.gni
@@ -37,7 +37,7 @@ declare_args() {
   slimpeller = false
 
   # Opt into new DL dispatcher that skips AIKS layer
-  experimental_canvas = false
+  experimental_canvas = true
 }
 
 # feature_defines_list ---------------------------------------------------------
diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 1c0bfb0cac4e1..a414372e89052 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -56,7 +56,6 @@ static const constexpr RenderTarget::AttachmentConfig kDefaultStencilConfig =
 static std::unique_ptr<EntityPassTarget> CreateRenderTarget(
     ContentContext& renderer,
     ISize size,
-    int mip_count,
     const Color& clear_color) {
   const std::shared_ptr<Context>& context = renderer.GetContext();
 
@@ -65,18 +64,12 @@ static std::unique_ptr<EntityPassTarget> CreateRenderTarget(
   /// What's important is the `StorageMode` of the textures, which cannot be
   /// changed for the lifetime of the textures.
 
-  if (context->GetBackendType() == Context::BackendType::kOpenGLES) {
-    // TODO(https://github.com/flutter/flutter/issues/141732): Implement mip map
-    // generation on opengles.
-    mip_count = 1;
-  }
-
   RenderTarget target;
   if (context->GetCapabilities()->SupportsOffscreenMSAA()) {
     target = renderer.GetRenderTargetCache()->CreateOffscreenMSAA(
         /*context=*/*context,
         /*size=*/size,
-        /*mip_count=*/mip_count,
+        /*mip_count=*/1,
         /*label=*/"EntityPass",
         /*color_attachment_config=*/
         RenderTarget::AttachmentConfigMSAA{
@@ -90,7 +83,7 @@ static std::unique_ptr<EntityPassTarget> CreateRenderTarget(
     target = renderer.GetRenderTargetCache()->CreateOffscreen(
         *context,  // context
         size,      // size
-        /*mip_count=*/mip_count,
+        /*mip_count=*/1,
         "EntityPass",  // label
         RenderTarget::AttachmentConfig{
             .storage_mode = StorageMode::kDevicePrivate,
@@ -172,12 +165,10 @@ void ExperimentalCanvas::SetupRenderPass() {
   // a second save layer with the same dimensions as the onscreen. When
   // rendering is completed, we must blit this saveLayer to the onscreen.
   if (requires_readback_) {
-    auto entity_pass_target = CreateRenderTarget(
-        renderer_,                  //
-        color0.texture->GetSize(),  //
-        // Note: this is incorrect, we also need to know what kind of filter.
-        /*mip_count=*/4,  //
-        /*clear_color=*/Color::BlackTransparent());
+    auto entity_pass_target =
+        CreateRenderTarget(renderer_,                  //
+                           color0.texture->GetSize(),  //
+                           /*clear_color=*/Color::BlackTransparent());
     render_passes_.push_back(
         LazyRenderingConfig(renderer_, std::move(entity_pass_target)));
   } else {
@@ -379,7 +370,8 @@ void ExperimentalCanvas::SaveLayer(
       renderer_,                                             //
       CreateRenderTarget(renderer_,                          //
                          ISize(subpass_coverage.GetSize()),  //
-                         1u, Color::BlackTransparent())));
+                         Color::BlackTransparent()           //
+                         )));
   save_layer_state_.push_back(SaveLayerState{paint_copy, subpass_coverage});
 
   CanvasStackEntry entry;

From c148f01bdc82dfd56319a754505e8eec2c98702d Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 9 Jul 2024 13:16:49 -0700
Subject: [PATCH 02/37] remove redefinition

---
 impeller/golden_tests/golden_playground_test_mac.cc | 2 --
 1 file changed, 2 deletions(-)

diff --git a/impeller/golden_tests/golden_playground_test_mac.cc b/impeller/golden_tests/golden_playground_test_mac.cc
index d5cb282c4bf98..7a2b674dbc049 100644
--- a/impeller/golden_tests/golden_playground_test_mac.cc
+++ b/impeller/golden_tests/golden_playground_test_mac.cc
@@ -24,8 +24,6 @@
 #define GLFW_INCLUDE_NONE
 #include "third_party/glfw/include/GLFW/glfw3.h"
 
-#define EXPERIMENTAL_CANVAS false
-
 namespace impeller {
 
 namespace {

From 5e3ebb187b98f26de1480ee631f3071c7e41eda7 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 9 Jul 2024 13:53:40 -0700
Subject: [PATCH 03/37] temp test adaption.

---
 shell/gpu/gpu_surface_metal_impeller_unittests.mm | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/shell/gpu/gpu_surface_metal_impeller_unittests.mm b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
index 13ccbba3f6906..4164a242bef1d 100644
--- a/shell/gpu/gpu_surface_metal_impeller_unittests.mm
+++ b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
@@ -109,19 +109,31 @@ GPUCAMetalLayerHandle GetCAMetalLayer(const SkISize& frame_info) const override
 
   auto& host_buffer = surface->GetAiksContext()->GetContentContext().GetTransientsBuffer();
 
+#if EXPERIMENTAL_CANVAS
+  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
+#else
   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
+#endif  // EXPERIMENTAL_CANVAS
 
   auto frame = surface->AcquireFrame(SkISize::Make(100, 100));
   frame->set_submit_info({.frame_boundary = false});
 
   ASSERT_TRUE(frame->Submit());
+#if EXPERIMENTAL_CANVAS
+  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
+#else
   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
+#endif  // EXPERIMENTAL_CANVAS
 
   frame = surface->AcquireFrame(SkISize::Make(100, 100));
   frame->set_submit_info({.frame_boundary = true});
 
   ASSERT_TRUE(frame->Submit());
+#if EXPERIMENTAL_CANVAS
+  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 2u);
+#else
   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
+#endif  // EXPERIMENTAL_CANVAS
 }
 
 }  // namespace testing

From 492f4613d246b7c3181f8ac0bebc2559c08b1e7c Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 9 Jul 2024 14:15:27 -0700
Subject: [PATCH 04/37] fix host buffer reset for exp canvas.

---
 shell/gpu/gpu_surface_metal_impeller.mm           |  5 ++++-
 shell/gpu/gpu_surface_metal_impeller_unittests.mm | 11 -----------
 shell/gpu/gpu_surface_vulkan_impeller.cc          |  7 +++++--
 3 files changed, 9 insertions(+), 14 deletions(-)

diff --git a/shell/gpu/gpu_surface_metal_impeller.mm b/shell/gpu/gpu_surface_metal_impeller.mm
index bc9bfd78d2ffb..8647d2897fc62 100644
--- a/shell/gpu/gpu_surface_metal_impeller.mm
+++ b/shell/gpu/gpu_surface_metal_impeller.mm
@@ -162,6 +162,7 @@
 
         impeller::IRect cull_rect = surface->coverage();
         SkIRect sk_cull_rect = SkIRect::MakeWH(cull_rect.GetWidth(), cull_rect.GetHeight());
+        const bool reset_host_buffer = surface_frame.submit_info().frame_boundary;
 
 #if EXPERIMENTAL_CANVAS
         impeller::TextFrameDispatcher collector(aiks_context->GetContentContext(),
@@ -179,13 +180,15 @@
               impeller_dispatcher.FinishRecording();
               aiks_context->GetContentContext().GetTransientsBuffer().Reset();
               aiks_context->GetContentContext().GetLazyGlyphAtlas()->ResetTextFrames();
+              if (reset_host_buffer) {
+                aiks_context->GetContentContext().GetTransientsBuffer().Reset();
+              }
               return true;
             }));
 #else
         impeller::DlDispatcher impeller_dispatcher(cull_rect);
         display_list->Dispatch(impeller_dispatcher, sk_cull_rect);
         auto picture = impeller_dispatcher.EndRecordingAsPicture();
-        const bool reset_host_buffer = surface_frame.submit_info().frame_boundary;
 
         return renderer->Render(
             std::move(surface),
diff --git a/shell/gpu/gpu_surface_metal_impeller_unittests.mm b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
index 4164a242bef1d..ff33d438450e3 100644
--- a/shell/gpu/gpu_surface_metal_impeller_unittests.mm
+++ b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
@@ -109,31 +109,20 @@ GPUCAMetalLayerHandle GetCAMetalLayer(const SkISize& frame_info) const override
 
   auto& host_buffer = surface->GetAiksContext()->GetContentContext().GetTransientsBuffer();
 
-#if EXPERIMENTAL_CANVAS
   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
-#else
   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
-#endif  // EXPERIMENTAL_CANVAS
 
   auto frame = surface->AcquireFrame(SkISize::Make(100, 100));
   frame->set_submit_info({.frame_boundary = false});
 
   ASSERT_TRUE(frame->Submit());
-#if EXPERIMENTAL_CANVAS
-  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
-#else
   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
-#endif  // EXPERIMENTAL_CANVAS
 
   frame = surface->AcquireFrame(SkISize::Make(100, 100));
   frame->set_submit_info({.frame_boundary = true});
 
   ASSERT_TRUE(frame->Submit());
-#if EXPERIMENTAL_CANVAS
-  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 2u);
-#else
   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
-#endif  // EXPERIMENTAL_CANVAS
 }
 
 }  // namespace testing
diff --git a/shell/gpu/gpu_surface_vulkan_impeller.cc b/shell/gpu/gpu_surface_vulkan_impeller.cc
index d32cef7e6ea4c..ebd2751a1f11c 100644
--- a/shell/gpu/gpu_surface_vulkan_impeller.cc
+++ b/shell/gpu/gpu_surface_vulkan_impeller.cc
@@ -87,6 +87,8 @@ std::unique_ptr<SurfaceFrame> GPUSurfaceVulkanImpeller::AcquireFrame(
             std::move(surface),
             fml::MakeCopyable([&](impeller::RenderTarget& render_target)
                                   -> bool {
+              const bool reset_host_buffer =
+                  surface_frame.submit_info().frame_boundary;
 #if EXPERIMENTAL_CANVAS
               impeller::TextFrameDispatcher collector(
                   aiks_context->GetContentContext(), impeller::Matrix());
@@ -107,6 +109,9 @@ std::unique_ptr<SurfaceFrame> GPUSurfaceVulkanImpeller::AcquireFrame(
               aiks_context->GetContentContext()
                   .GetLazyGlyphAtlas()
                   ->ResetTextFrames();
+              if (reset_host_buffer) {
+                aiks_context->GetContentContext().GetTransientsBuffer().Reset();
+              }
               return true;
 #else
               impeller::Rect dl_cull_rect = impeller::Rect::MakeSize(cull_rect);
@@ -115,8 +120,6 @@ std::unique_ptr<SurfaceFrame> GPUSurfaceVulkanImpeller::AcquireFrame(
                   impeller_dispatcher,
                   SkIRect::MakeWH(cull_rect.width, cull_rect.height));
               auto picture = impeller_dispatcher.EndRecordingAsPicture();
-              const bool reset_host_buffer =
-                  surface_frame.submit_info().frame_boundary;
               return aiks_context->Render(picture, render_target,
                                           reset_host_buffer);
 #endif

From ff2fa94400d7f2c18649c933984a247749ca2bca Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 9 Jul 2024 14:26:36 -0700
Subject: [PATCH 05/37] add capture for reset_host_buffer

---
 shell/gpu/gpu_surface_metal_impeller.mm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/shell/gpu/gpu_surface_metal_impeller.mm b/shell/gpu/gpu_surface_metal_impeller.mm
index 8647d2897fc62..c5b854f339766 100644
--- a/shell/gpu/gpu_surface_metal_impeller.mm
+++ b/shell/gpu/gpu_surface_metal_impeller.mm
@@ -171,7 +171,7 @@
         return renderer->Render(
             std::move(surface),
             fml::MakeCopyable([aiks_context, &display_list, &cull_rect,
-                               &sk_cull_rect](impeller::RenderTarget& render_target) -> bool {
+                               &sk_cull_rect, reset_host_buffer](impeller::RenderTarget& render_target) -> bool {
               impeller::ExperimentalDlDispatcher impeller_dispatcher(
                   aiks_context->GetContentContext(), render_target,
                   display_list->root_has_backdrop_filter(), display_list->max_root_blend_mode(),

From a2ef961aeba90c431822d9f35790a260984cef7a Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 9 Jul 2024 15:50:12 -0700
Subject: [PATCH 06/37] capture.

---
 shell/gpu/gpu_surface_metal_impeller.mm | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/shell/gpu/gpu_surface_metal_impeller.mm b/shell/gpu/gpu_surface_metal_impeller.mm
index c5b854f339766..45d60b55d15ba 100644
--- a/shell/gpu/gpu_surface_metal_impeller.mm
+++ b/shell/gpu/gpu_surface_metal_impeller.mm
@@ -170,8 +170,8 @@
         display_list->Dispatch(collector, sk_cull_rect);
         return renderer->Render(
             std::move(surface),
-            fml::MakeCopyable([aiks_context, &display_list, &cull_rect,
-                               &sk_cull_rect, reset_host_buffer](impeller::RenderTarget& render_target) -> bool {
+            fml::MakeCopyable([aiks_context, &display_list, &cull_rect, &sk_cull_rect,
+                               &reset_host_buffer](impeller::RenderTarget& render_target) -> bool {
               impeller::ExperimentalDlDispatcher impeller_dispatcher(
                   aiks_context->GetContentContext(), render_target,
                   display_list->root_has_backdrop_filter(), display_list->max_root_blend_mode(),
@@ -193,7 +193,7 @@
         return renderer->Render(
             std::move(surface),
             fml::MakeCopyable([aiks_context, picture = std::move(picture),
-                               reset_host_buffer](impeller::RenderTarget& render_target) -> bool {
+                               &reset_host_buffer](impeller::RenderTarget& render_target) -> bool {
               return aiks_context->Render(picture, render_target, reset_host_buffer);
             }));
 #endif

From 2432a3ff47db3e7f2d9ac2e8eb71ad9e7a5d7a50 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 9 Jul 2024 16:51:00 -0700
Subject: [PATCH 07/37] remove extra assert.

---
 shell/gpu/gpu_surface_metal_impeller_unittests.mm | 1 -
 1 file changed, 1 deletion(-)

diff --git a/shell/gpu/gpu_surface_metal_impeller_unittests.mm b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
index ff33d438450e3..13ccbba3f6906 100644
--- a/shell/gpu/gpu_surface_metal_impeller_unittests.mm
+++ b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
@@ -109,7 +109,6 @@ GPUCAMetalLayerHandle GetCAMetalLayer(const SkISize& frame_info) const override
 
   auto& host_buffer = surface->GetAiksContext()->GetContentContext().GetTransientsBuffer();
 
-  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
 
   auto frame = surface->AcquireFrame(SkISize::Make(100, 100));

From f0a0114d4771c6cf2dc72bac690e66fbd4002e9c Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 9 Jul 2024 18:38:46 -0700
Subject: [PATCH 08/37] temp disable for testing.

---
 .../gpu_surface_metal_impeller_unittests.mm   | 37 ++++++++++---------
 1 file changed, 19 insertions(+), 18 deletions(-)

diff --git a/shell/gpu/gpu_surface_metal_impeller_unittests.mm b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
index 13ccbba3f6906..f7599fea2b6e9 100644
--- a/shell/gpu/gpu_surface_metal_impeller_unittests.mm
+++ b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
@@ -97,32 +97,33 @@ GPUCAMetalLayerHandle GetCAMetalLayer(const SkISize& frame_info) const override
   ASSERT_TRUE(frame->Submit());
 }
 
-TEST(GPUSurfaceMetalImpeller, ResetHostBufferBasedOnFrameBoundary) {
-  auto delegate = std::make_shared<TestGPUSurfaceMetalDelegate>();
-  delegate->SetDevice();
+// TESTING!
+// TEST(GPUSurfaceMetalImpeller, ResetHostBufferBasedOnFrameBoundary) {
+//   auto delegate = std::make_shared<TestGPUSurfaceMetalDelegate>();
+//   delegate->SetDevice();
 
-  auto context = CreateImpellerContext();
-  std::unique_ptr<Surface> surface =
-      std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), CreateImpellerContext());
+//   auto context = CreateImpellerContext();
+//   std::unique_ptr<Surface> surface =
+//       std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), CreateImpellerContext());
 
-  ASSERT_TRUE(surface->IsValid());
+//   ASSERT_TRUE(surface->IsValid());
 
-  auto& host_buffer = surface->GetAiksContext()->GetContentContext().GetTransientsBuffer();
+//   auto& host_buffer = surface->GetAiksContext()->GetContentContext().GetTransientsBuffer();
 
-  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
+//   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
 
-  auto frame = surface->AcquireFrame(SkISize::Make(100, 100));
-  frame->set_submit_info({.frame_boundary = false});
+//   auto frame = surface->AcquireFrame(SkISize::Make(100, 100));
+//   frame->set_submit_info({.frame_boundary = false});
 
-  ASSERT_TRUE(frame->Submit());
-  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
+//   ASSERT_TRUE(frame->Submit());
+//   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
 
-  frame = surface->AcquireFrame(SkISize::Make(100, 100));
-  frame->set_submit_info({.frame_boundary = true});
+//   frame = surface->AcquireFrame(SkISize::Make(100, 100));
+//   frame->set_submit_info({.frame_boundary = true});
 
-  ASSERT_TRUE(frame->Submit());
-  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
-}
+//   ASSERT_TRUE(frame->Submit());
+//   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
+// }
 
 }  // namespace testing
 }  // namespace flutter

From 188ecd16e2256bcda453e567f8756cfd982cd335 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 10 Jul 2024 14:56:57 -0700
Subject: [PATCH 09/37] cull rect correctly

---
 impeller/aiks/experimental_canvas.cc | 50 +++++++++++++++++-----------
 1 file changed, 30 insertions(+), 20 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index a414372e89052..67317ea3bf948 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -203,6 +203,19 @@ void ExperimentalCanvas::SaveLayer(
     ContentBoundsPromise bounds_promise,
     uint32_t total_content_depth,
     bool can_distribute_opacity) {
+  if (!clip_coverage_stack_.HasCoverage()) {
+    // The current clip is empty. This means the pass texture won't be
+    // visible, so skip it.
+    Save(total_content_depth);
+    return;
+  }
+
+  auto clip_coverage_back = clip_coverage_stack_.CurrentClipCoverage();
+  if (!clip_coverage_back.has_value()) {
+    Save(total_content_depth);
+    return;
+  }
+
   // Can we always guarantee that we get a bounds? Does a lack of bounds
   // indicate something?
   if (!bounds.has_value()) {
@@ -218,28 +231,25 @@ void ExperimentalCanvas::SaveLayer(
 
   // The maximum coverage of the subpass. Subpasses textures should never
   // extend outside the parent pass texture or the current clip coverage.
-  Rect coverage_limit = Rect::MakeOriginSize(
-      GetGlobalPassPosition(),
-      Size(render_passes_.back().inline_pass_context->GetTexture()->GetSize()));
+  std::optional<Rect> maybe_coverage_limit =
+      Rect::MakeOriginSize(GetGlobalPassPosition(),
+                           Size(render_passes_.back()
+                                    .inline_pass_context->GetTexture()
+                                    ->GetSize()))
+          .Intersection(clip_coverage_back.value());
+
+  if (!maybe_coverage_limit.has_value()) {
+    Save(total_content_depth);
+    return;
+  }
+  maybe_coverage_limit = maybe_coverage_limit->Intersection(
+      Rect::MakeSize(render_target_.GetRenderTargetSize()));
 
-  // BDF No-op. need to do some precomputation to ensure this is fully skipped.
-  if (backdrop_filter) {
-    if (!clip_coverage_stack_.HasCoverage()) {
-      Save(total_content_depth);
-      return;
-    }
-    auto maybe_clip_coverage = clip_coverage_stack_.CurrentClipCoverage();
-    if (!maybe_clip_coverage.has_value()) {
-      Save(total_content_depth);
-      return;
-    }
-    auto clip_coverage = maybe_clip_coverage.value();
-    if (clip_coverage.IsEmpty() ||
-        !coverage_limit.IntersectsWithRect(clip_coverage)) {
-      Save(total_content_depth);
-      return;
-    }
+  if (!maybe_coverage_limit.has_value() || maybe_coverage_limit->IsEmpty()) {
+    Save(total_content_depth);
+    return;
   }
+  auto coverage_limit = maybe_coverage_limit.value();
 
   if (can_distribute_opacity && !backdrop_filter &&
       Paint::CanApplyOpacityPeephole(paint)) {

From 0c2926e13f0d86dd5aca5614fa1e123518289e9c Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 23 Jul 2024 11:18:44 -0700
Subject: [PATCH 10/37] ++

---
 shell/common/snapshot_controller_impeller.cc | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/shell/common/snapshot_controller_impeller.cc b/shell/common/snapshot_controller_impeller.cc
index 3f926b5025bcd..9233fce8e93c1 100644
--- a/shell/common/snapshot_controller_impeller.cc
+++ b/shell/common/snapshot_controller_impeller.cc
@@ -48,7 +48,6 @@ sk_sp<DlImage> DoMakeRasterSnapshot(
 #if EXPERIMENTAL_CANVAS
   // Do not use the render target cache as the lifecycle of this texture
   // will outlive a particular frame.
-  impeller::ISize impeller_size = impeller::ISize(size.width(), size.height());
   impeller::RenderTargetAllocator render_target_allocator =
       impeller::RenderTargetAllocator(
           context->GetContext()->GetResourceAllocator());
@@ -56,7 +55,7 @@ sk_sp<DlImage> DoMakeRasterSnapshot(
   if (context->GetContext()->GetCapabilities()->SupportsOffscreenMSAA()) {
     target = render_target_allocator.CreateOffscreenMSAA(
         *context->GetContext(),  // context
-        impeller_size,           // size
+        render_target_size,      // size
         /*mip_count=*/1,
         "Picture Snapshot MSAA",  // label
         impeller::RenderTarget::
@@ -65,7 +64,7 @@ sk_sp<DlImage> DoMakeRasterSnapshot(
   } else {
     target = render_target_allocator.CreateOffscreen(
         *context->GetContext(),  // context
-        impeller_size,           // size
+        render_target_size,      // size
         /*mip_count=*/1,
         "Picture Snapshot",  // label
         impeller::RenderTarget::

From f42ec97097ec63bbd37047da7580ab19dac90639 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 23 Jul 2024 12:32:27 -0700
Subject: [PATCH 11/37] ++

---
 shell/common/snapshot_controller_impeller.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/shell/common/snapshot_controller_impeller.cc b/shell/common/snapshot_controller_impeller.cc
index 9233fce8e93c1..68bc9ac46a3c8 100644
--- a/shell/common/snapshot_controller_impeller.cc
+++ b/shell/common/snapshot_controller_impeller.cc
@@ -79,7 +79,7 @@ sk_sp<DlImage> DoMakeRasterSnapshot(
       context->GetContentContext(), target,
       display_list->root_has_backdrop_filter(),
       display_list->max_root_blend_mode(),
-      impeller::IRect::MakeSize(impeller_size));
+      impeller::IRect::MakeSize(render_target_size));
   display_list->Dispatch(impeller_dispatcher, SkIRect::MakeSize(size));
   impeller_dispatcher.FinishRecording();
 

From 239402c6f1f1a045409a9a06059359370018d93e Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 23 Jul 2024 13:47:24 -0700
Subject: [PATCH 12/37] add back trace event.

---
 impeller/aiks/experimental_canvas.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 67317ea3bf948..84309b57c18ec 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -4,6 +4,7 @@
 
 #include "impeller/aiks/experimental_canvas.h"
 #include "fml/logging.h"
+#include "fml/trace_event.h"
 #include "impeller/aiks/canvas.h"
 #include "impeller/aiks/paint_pass_delegate.h"
 #include "impeller/base/validation.h"
@@ -203,6 +204,8 @@ void ExperimentalCanvas::SaveLayer(
     ContentBoundsPromise bounds_promise,
     uint32_t total_content_depth,
     bool can_distribute_opacity) {
+  TRACE_EVENT0("flutter", "Canvas::saveLayer");
+
   if (!clip_coverage_stack_.HasCoverage()) {
     // The current clip is empty. This means the pass texture won't be
     // visible, so skip it.

From 3a355557d23fc600f41c0189aec807360e5d4f8b Mon Sep 17 00:00:00 2001
From: Jonah Williams <jonahwilliams@google.com>
Date: Thu, 25 Jul 2024 09:43:43 -0700
Subject: [PATCH 13/37] Update gpu_surface_metal_impeller_unittests.mm

---
 .../gpu_surface_metal_impeller_unittests.mm   | 44 +++++++++----------
 1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/shell/gpu/gpu_surface_metal_impeller_unittests.mm b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
index 885d7b13ce329..94bde0eb25fc5 100644
--- a/shell/gpu/gpu_surface_metal_impeller_unittests.mm
+++ b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
@@ -125,35 +125,35 @@ GPUCAMetalLayerHandle GetCAMetalLayer(const SkISize& frame_info) const override
 //   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
 // }
 
-#ifdef IMPELLER_DEBUG
-TEST(GPUSurfaceMetalImpeller, CreatesImpellerCaptureScope) {
-  auto delegate = std::make_shared<TestGPUSurfaceMetalDelegate>();
-  delegate->SetDevice();
+// #ifdef IMPELLER_DEBUG
+// TEST(GPUSurfaceMetalImpeller, CreatesImpellerCaptureScope) {
+//   auto delegate = std::make_shared<TestGPUSurfaceMetalDelegate>();
+//   delegate->SetDevice();
 
-  auto context = CreateImpellerContext();
+//   auto context = CreateImpellerContext();
 
-  EXPECT_FALSE(context->GetCaptureManager()->CaptureScopeActive());
+//   EXPECT_FALSE(context->GetCaptureManager()->CaptureScopeActive());
 
-  std::unique_ptr<Surface> surface =
-      std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
-  auto frame_1 = surface->AcquireFrame(SkISize::Make(100, 100));
-  frame_1->set_submit_info({.frame_boundary = false});
+//   std::unique_ptr<Surface> surface =
+//       std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
+//   auto frame_1 = surface->AcquireFrame(SkISize::Make(100, 100));
+//   frame_1->set_submit_info({.frame_boundary = false});
 
-  EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
+//   EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
 
-  std::unique_ptr<Surface> surface_2 =
-      std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
-  auto frame_2 = surface->AcquireFrame(SkISize::Make(100, 100));
-  frame_2->set_submit_info({.frame_boundary = true});
+//   std::unique_ptr<Surface> surface_2 =
+//       std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
+//   auto frame_2 = surface->AcquireFrame(SkISize::Make(100, 100));
+//   frame_2->set_submit_info({.frame_boundary = true});
 
-  EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
+//   EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
 
-  ASSERT_TRUE(frame_1->Submit());
-  EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
-  ASSERT_TRUE(frame_2->Submit());
-  EXPECT_FALSE(context->GetCaptureManager()->CaptureScopeActive());
-}
-#endif  // IMPELLER_DEBUG
+//   ASSERT_TRUE(frame_1->Submit());
+//   EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
+//   ASSERT_TRUE(frame_2->Submit());
+//   EXPECT_FALSE(context->GetCaptureManager()->CaptureScopeActive());
+// }
+// #endif  // IMPELLER_DEBUG
 
 }  // namespace testing
 }  // namespace flutter

From 45c00cfc65311b6dcf7c0d2f914570da25d82f1f Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 25 Jul 2024 15:41:33 -0700
Subject: [PATCH 14/37] ++

---
 impeller/aiks/experimental_canvas.cc | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index e1c1dc18a695b..3697e07b60355 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -705,8 +705,29 @@ void ExperimentalCanvas::AddRenderEntityToCurrentPass(Entity entity,
     if (renderer_.GetDeviceCapabilities().SupportsFramebufferFetch()) {
       ApplyFramebufferBlend(entity);
     } else {
-      VALIDATION_LOG << "Emulated advanced blends are currently unsupported.";
-      return;
+      // End the active pass and flush the buffer before rendering "advanced"
+      // blends. Advanced blends work by binding the current render target
+      // texture as an input ("destination"), blending with a second texture
+      // input ("source"), writing the result to an intermediate texture, and
+      // finally copying the data from the intermediate texture back to the
+      // render target texture. And so all of the commands that have written
+      // to the render target texture so far need to execute before it's bound
+      // for blending (otherwise the blend pass will end up executing before
+      // all the previous commands in the active pass).
+      auto input_texture = FlipBackdrop(render_passes_, GetGlobalPassPosition(),
+                                        clip_coverage_stack_, renderer_);
+      if (!input_texture) {
+        return;
+      }
+
+      FilterInput::Vector inputs = {
+          FilterInput::Make(input_texture, entity.GetTransform().Invert()),
+          FilterInput::Make(entity.GetContents())};
+      auto contents =
+          ColorFilterContents::MakeBlend(entity.GetBlendMode(), inputs);
+      contents->SetCoverageHint(entity.GetCoverage());
+      entity.SetContents(std::move(contents));
+      entity.SetBlendMode(BlendMode::kSource);
     }
   }
 

From 94b4340ff540416218a308562b90bb6e2121eb87 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 25 Jul 2024 17:08:27 -0700
Subject: [PATCH 15/37] fix entity pass flip

---
 impeller/aiks/experimental_canvas.cc | 23 ++++++++++++-----------
 impeller/aiks/experimental_canvas.h  |  6 ++++++
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 3697e07b60355..ecf99a3e02136 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -83,13 +83,13 @@ static std::shared_ptr<Texture> FlipBackdrop(
     // unbalanced save layers. Ideally, this method would return false and the
     // renderer could handle that by terminating dispatch.
     render_passes.push_back(LazyRenderingConfig(
-        renderer, std::move(rendering_config.entity_pass_target)));
+        renderer, std::move(rendering_config.entity_pass_target),
+        std::move(rendering_config.inline_pass_context)));
     return nullptr;
   }
 
   std::shared_ptr<Texture> input_texture =
-      rendering_config.entity_pass_target->Flip(
-          *renderer.GetContext()->GetResourceAllocator());
+      rendering_config.inline_pass_context->GetTexture();
 
   if (!input_texture) {
     VALIDATION_LOG << "Failed to fetch the color texture in order to "
@@ -97,12 +97,14 @@ static std::shared_ptr<Texture> FlipBackdrop(
 
     // Note: see above.
     render_passes.push_back(LazyRenderingConfig(
-        renderer, std::move(rendering_config.entity_pass_target)));
+        renderer, std::move(rendering_config.entity_pass_target),
+        std::move(rendering_config.inline_pass_context)));
     return nullptr;
   }
 
   render_passes.push_back(LazyRenderingConfig(
-      renderer, std::move(rendering_config.entity_pass_target)));
+      renderer, std::move(rendering_config.entity_pass_target),
+      std::move(rendering_config.inline_pass_context)));
   // Eagerly restore the BDF contents.
 
   // If the pass context returns a backdrop texture, we need to draw it to the
@@ -674,14 +676,13 @@ void ExperimentalCanvas::AddRenderEntityToCurrentPass(Entity entity,
   // conditionally update the backdrop color to its solid color value blended
   // with the current backdrop.
   if (render_passes_.back().IsApplyingClearColor()) {
-    std::optional<Color> maybe_color =
-        entity.AsBackgroundColor(render_passes_.back()
-                                     .entity_pass_target->GetRenderTarget()
-                                     .GetRenderTargetSize());
+    std::optional<Color> maybe_color = entity.AsBackgroundColor(
+        render_passes_.back().inline_pass_context->GetTexture()->GetSize());
     if (maybe_color.has_value()) {
       Color color = maybe_color.value();
-      RenderTarget& render_target =
-          render_passes_.back().entity_pass_target->GetRenderTarget();
+      RenderTarget& render_target = render_passes_.back()
+                                        .inline_pass_context->GetPassTarget()
+                                        .GetRenderTarget();
       ColorAttachment attachment =
           render_target.GetColorAttachments().find(0u)->second;
       attachment.clear_color = attachment.clear_color.Unpremultiply()
diff --git a/impeller/aiks/experimental_canvas.h b/impeller/aiks/experimental_canvas.h
index d1868441b7545..debb4baf088fc 100644
--- a/impeller/aiks/experimental_canvas.h
+++ b/impeller/aiks/experimental_canvas.h
@@ -31,6 +31,12 @@ struct LazyRenderingConfig {
     inline_pass_context =
         std::make_unique<InlinePassContext>(renderer, *entity_pass_target, 0);
   }
+
+  LazyRenderingConfig(ContentContext& renderer,
+                      std::unique_ptr<EntityPassTarget> entity_pass_target,
+                      std::unique_ptr<InlinePassContext> inline_pass_context)
+      : entity_pass_target(std::move(entity_pass_target)),
+        inline_pass_context(std::move(inline_pass_context)) {}
 };
 
 /// This Canvas attempts to translate from display lists to draw calls directly.

From ed8ad3f3561bd0e3e7a747241648f395e377b9ad Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 30 Jul 2024 17:12:20 -0700
Subject: [PATCH 16/37] ++

---
 impeller/aiks/experimental_canvas.cc | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index ecf99a3e02136..de65dfe68043e 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -322,15 +322,15 @@ void ExperimentalCanvas::SaveLayer(
     return;
   }
 
-  // Can we always guarantee that we get a bounds? Does a lack of bounds
-  // indicate something?
-  if (!bounds.has_value()) {
-    bounds = Rect::MakeSize(render_target_.GetRenderTargetSize());
-  }
+  // // Can we always guarantee that we get a bounds? Does a lack of bounds
+  // // indicate something?
+  // if (!bounds.has_value()) {
+  //   bounds = Rect::MakeSize(render_target_.GetRenderTargetSize());
+  // }
 
   // SaveLayer is a no-op, depending on the bounds promise. Should/Can DL elide
   // this?
-  if (bounds->IsEmpty()) {
+  if (bounds.has_value() && bounds->IsEmpty()) {
     Save(total_content_depth);
     return;
   }
@@ -408,7 +408,8 @@ void ExperimentalCanvas::SaveLayer(
   // Backdrop Filter must expand bounds to at least the clip stack, otherwise
   // the coverage of the parent render pass.
   Rect subpass_coverage = bounds->TransformBounds(GetCurrentTransform());
-  if (backdrop_filter_contents) {
+  if (backdrop_filter_contents ||
+      Entity::IsBlendModeDestructive(paint.blend_mode)) {
     FML_CHECK(clip_coverage_stack_.HasCoverage());
     // We should never hit this case as we check the intersection above.
     // NOLINTBEGIN(bugprone-unchecked-optional-access)

From 5b9c14b65bbfa4893911c43374670306b1309709 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 30 Jul 2024 19:14:42 -0700
Subject: [PATCH 17/37] ++

---
 shell/gpu/gpu_surface_metal_impeller.mm  | 4 ++--
 shell/gpu/gpu_surface_vulkan_impeller.cc | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/shell/gpu/gpu_surface_metal_impeller.mm b/shell/gpu/gpu_surface_metal_impeller.mm
index 9d7f1015e371b..30569cdcd11fd 100644
--- a/shell/gpu/gpu_surface_metal_impeller.mm
+++ b/shell/gpu/gpu_surface_metal_impeller.mm
@@ -161,7 +161,7 @@
         SkIRect sk_cull_rect = SkIRect::MakeWH(cull_rect.GetWidth(), cull_rect.GetHeight());
         const bool reset_host_buffer = surface_frame.submit_info().frame_boundary;
 
-        const impeller::RenderTarget& render_target = surface->GetTargetRenderPassDescriptor();
+        impeller::RenderTarget render_target = surface->GetTargetRenderPassDescriptor();
         surface->SetFrameBoundary(surface_frame.submit_info().frame_boundary);
 
         surface_frame.set_user_data(std::move(surface));
@@ -284,7 +284,7 @@
         impeller::TextFrameDispatcher collector(aiks_context->GetContentContext(),
                                                 impeller::Matrix());
         display_list->Dispatch(collector, sk_cull_rect);
-        const impeller::RenderTarget& render_target = surface->GetTargetRenderPassDescriptor();
+        impeller::RenderTarget render_target = surface->GetTargetRenderPassDescriptor();
         impeller::ExperimentalDlDispatcher impeller_dispatcher(
             aiks_context->GetContentContext(), render_target,
             display_list->root_has_backdrop_filter(), display_list->max_root_blend_mode(),
diff --git a/shell/gpu/gpu_surface_vulkan_impeller.cc b/shell/gpu/gpu_surface_vulkan_impeller.cc
index 12f5810e0363a..02a9a4dfd5908 100644
--- a/shell/gpu/gpu_surface_vulkan_impeller.cc
+++ b/shell/gpu/gpu_surface_vulkan_impeller.cc
@@ -62,7 +62,7 @@ std::unique_ptr<SurfaceFrame> GPUSurfaceVulkanImpeller::AcquireFrame(
   auto cull_rect =
       surface->GetTargetRenderPassDescriptor().GetRenderTargetSize();
 
-  const impeller::RenderTarget& render_target =
+  impeller::RenderTarget render_target =
       surface->GetTargetRenderPassDescriptor();
 
   SurfaceFrame::EncodeCallback encode_callback = [aiks_context =

From c5ad6785edd8497640b9b695d2c5ce80ee55c5b2 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 30 Jul 2024 20:24:51 -0700
Subject: [PATCH 18/37] check bounds.

---
 impeller/aiks/experimental_canvas.cc | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index de65dfe68043e..26eb1d6474e43 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -407,9 +407,9 @@ void ExperimentalCanvas::SaveLayer(
 
   // Backdrop Filter must expand bounds to at least the clip stack, otherwise
   // the coverage of the parent render pass.
-  Rect subpass_coverage = bounds->TransformBounds(GetCurrentTransform());
+  Rect subpass_coverage;
   if (backdrop_filter_contents ||
-      Entity::IsBlendModeDestructive(paint.blend_mode)) {
+      Entity::IsBlendModeDestructive(paint.blend_mode) || !bounds.has_value()) {
     FML_CHECK(clip_coverage_stack_.HasCoverage());
     // We should never hit this case as we check the intersection above.
     // NOLINTBEGIN(bugprone-unchecked-optional-access)
@@ -418,6 +418,8 @@ void ExperimentalCanvas::SaveLayer(
             .Intersection(clip_coverage_stack_.CurrentClipCoverage().value())
             .value();
     // NOLINTEND(bugprone-unchecked-optional-access)
+  } else {
+    subpass_coverage = bounds->TransformBounds(GetCurrentTransform());
   }
 
   render_passes_.push_back(LazyRenderingConfig(

From bbdec467d8d2aa218cc7122a9508a0251fbf8f79 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 30 Jul 2024 22:18:32 -0700
Subject: [PATCH 19/37] ++

---
 impeller/aiks/experimental_canvas.cc | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 26eb1d6474e43..4d55e94b9efe3 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -688,9 +688,8 @@ void ExperimentalCanvas::AddRenderEntityToCurrentPass(Entity entity,
                                         .GetRenderTarget();
       ColorAttachment attachment =
           render_target.GetColorAttachments().find(0u)->second;
-      attachment.clear_color = attachment.clear_color.Unpremultiply()
-                                   .Blend(color, entity.GetBlendMode())
-                                   .Premultiply();
+      attachment.clear_color =
+          attachment.clear_color.Blend(color, entity.GetBlendMode());
       render_target.SetColorAttachment(attachment, 0u);
     }
   }

From 35204a343ebd38c78ee500df612dcbbf40975b03 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 31 Jul 2024 11:00:04 -0700
Subject: [PATCH 20/37] more adjustments.

---
 impeller/aiks/aiks_playground.cc     | 21 +++++++++++++++++----
 impeller/aiks/experimental_canvas.cc |  7 +++++--
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/impeller/aiks/aiks_playground.cc b/impeller/aiks/aiks_playground.cc
index 82f76bf3372a4..882e0d66a99c2 100644
--- a/impeller/aiks/aiks_playground.cc
+++ b/impeller/aiks/aiks_playground.cc
@@ -75,10 +75,7 @@ bool AiksPlayground::ImGuiBegin(const char* name,
 
 bool AiksPlayground::OpenPlaygroundHere(
     const sk_sp<flutter::DisplayList>& list) {
-  DlDispatcher dispatcher;
-  list->Dispatch(dispatcher);
-  Picture picture = dispatcher.EndRecordingAsPicture();
-  return OpenPlaygroundHere(std::move(picture));
+  return OpenPlaygroundHere([list]() { return list; });
 }
 
 bool AiksPlayground::OpenPlaygroundHere(
@@ -91,12 +88,28 @@ bool AiksPlayground::OpenPlaygroundHere(
 
   return Playground::OpenPlaygroundHere(
       [&renderer, &callback](RenderTarget& render_target) -> bool {
+#if EXPERIMENTAL_CANVAS
+        auto display_list = callback();
+        TextFrameDispatcher collector(renderer.GetContentContext(), Matrix());
+        display_list->Dispatch(collector);
+
+        ExperimentalDlDispatcher impeller_dispatcher(
+            renderer.GetContentContext(), render_target,
+            display_list->root_has_backdrop_filter(),
+            display_list->max_root_blend_mode(), IRect::MakeMaximum());
+        display_list->Dispatch(impeller_dispatcher);
+        impeller_dispatcher.FinishRecording();
+        renderer.GetContentContext().GetTransientsBuffer().Reset();
+        renderer.GetContentContext().GetLazyGlyphAtlas()->ResetTextFrames();
+        return true;
+#else
         auto display_list = callback();
         DlDispatcher dispatcher;
         display_list->Dispatch(dispatcher);
         Picture picture = dispatcher.EndRecordingAsPicture();
 
         return renderer.Render(picture, render_target, true);
+#endif  // EXPERIMENTAL_CANVAS
       });
 }
 
diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 4d55e94b9efe3..084a983d78615 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -688,8 +688,11 @@ void ExperimentalCanvas::AddRenderEntityToCurrentPass(Entity entity,
                                         .GetRenderTarget();
       ColorAttachment attachment =
           render_target.GetColorAttachments().find(0u)->second;
-      attachment.clear_color =
-          attachment.clear_color.Blend(color, entity.GetBlendMode());
+      // Attachment.clear color needs to be premultiplied at all times, but the
+      // Color::Blend function requires unpremultiplied colors.
+      attachment.clear_color = attachment.clear_color.Unpremultiply()
+                                   .Blend(color, entity.GetBlendMode())
+                                   .Premultiply();
       render_target.SetColorAttachment(attachment, 0u);
     }
   }

From 50497ced8a07f1517185104af232d2ec79aa6d5f Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Fri, 9 Aug 2024 20:30:25 -0700
Subject: [PATCH 21/37] ++

---
 impeller/display_list/dl_dispatcher.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/impeller/display_list/dl_dispatcher.cc b/impeller/display_list/dl_dispatcher.cc
index 72c96acf8d6f0..06e91b69b3576 100644
--- a/impeller/display_list/dl_dispatcher.cc
+++ b/impeller/display_list/dl_dispatcher.cc
@@ -600,7 +600,7 @@ void DlDispatcherBase::saveLayer(const SkRect& bounds,
                      ? ContentBoundsPromise::kMayClipContents
                      : ContentBoundsPromise::kContainsContents;
   std::optional<Rect> impeller_bounds;
-  if (!options.content_is_unbounded()) {
+  if (!options.content_is_unbounded() || options.bounds_from_caller()) {
     impeller_bounds = skia_conversions::ToRect(bounds);
   }
 

From 464b21e221d7a3682623c9ca4c5bc3f14ef37e1a Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Fri, 9 Aug 2024 23:48:06 -0700
Subject: [PATCH 22/37] ++

---
 impeller/display_list/dl_dispatcher.cc              | 4 +++-
 impeller/golden_tests/golden_playground_test_mac.cc | 8 ++++----
 impeller/renderer/backend/metal/surface_mtl.h       | 4 ++--
 impeller/renderer/backend/metal/surface_mtl.mm      | 6 ++++--
 shell/gpu/gpu_surface_metal_impeller.mm             | 1 -
 5 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/impeller/display_list/dl_dispatcher.cc b/impeller/display_list/dl_dispatcher.cc
index 06e91b69b3576..787beab7020f2 100644
--- a/impeller/display_list/dl_dispatcher.cc
+++ b/impeller/display_list/dl_dispatcher.cc
@@ -1301,7 +1301,9 @@ void TextFrameDispatcher::drawTextFrame(
     properties.stroke_width = paint_.stroke_width;
   }
   if (text_frame->HasColor()) {
-    properties.color = paint_.color;
+    // Alpha is always applied when rendering, remove it here so
+    // we do not double-apply the alpha.
+    properties.color = paint_.color.WithAlpha(1.0);
   }
   auto scale =
       (matrix_ * Matrix::MakeTranslation(Point(x, y))).GetMaxBasisLengthXY();
diff --git a/impeller/golden_tests/golden_playground_test_mac.cc b/impeller/golden_tests/golden_playground_test_mac.cc
index 9ed2de77db427..8893b4e7842b4 100644
--- a/impeller/golden_tests/golden_playground_test_mac.cc
+++ b/impeller/golden_tests/golden_playground_test_mac.cc
@@ -89,18 +89,18 @@ std::shared_ptr<Texture> DisplayListToTexture(
     );
   }
 
+  SkIRect sk_cull_rect = SkIRect::MakeWH(size.width, size.height);
   impeller::TextFrameDispatcher collector(context.GetContentContext(),
                                           impeller::Matrix());
-  display_list->Dispatch(
-      collector, SkIRect::MakeSize(SkISize::Make(size.width, size.height)));
+  display_list->Dispatch(collector, sk_cull_rect);
   impeller::ExperimentalDlDispatcher impeller_dispatcher(
       context.GetContentContext(), target,
       display_list->root_has_backdrop_filter(),
       display_list->max_root_blend_mode(), impeller::IRect::MakeSize(size));
-  display_list->Dispatch(impeller_dispatcher, SkIRect::MakeSize(SkISize::Make(
-                                                  size.width, size.height)));
+  display_list->Dispatch(impeller_dispatcher, sk_cull_rect);
   impeller_dispatcher.FinishRecording();
 
+  context.GetContentContext().GetTransientsBuffer().Reset();
   context.GetContentContext().GetLazyGlyphAtlas()->ResetTextFrames();
 
   return target.GetRenderTargetTexture();
diff --git a/impeller/renderer/backend/metal/surface_mtl.h b/impeller/renderer/backend/metal/surface_mtl.h
index bff5072f8fb8b..a9c9c8ec6c0d5 100644
--- a/impeller/renderer/backend/metal/surface_mtl.h
+++ b/impeller/renderer/backend/metal/surface_mtl.h
@@ -66,7 +66,7 @@ class SurfaceMTL final : public Surface {
   }
 
   /// @brief Perform the final blit and trigger end of frame workloads.
-  bool PreparePresent();
+  bool PreparePresent() const;
 
   // |Surface|
   bool Present() const override;
@@ -85,7 +85,7 @@ class SurfaceMTL final : public Surface {
   std::optional<IRect> clip_rect_;
   bool frame_boundary_ = false;
   bool present_with_transaction_ = false;
-  bool prepared_ = false;
+  mutable bool prepared_ = false;
 
   static bool ShouldPerformPartialRepaint(std::optional<IRect> damage_rect);
 
diff --git a/impeller/renderer/backend/metal/surface_mtl.mm b/impeller/renderer/backend/metal/surface_mtl.mm
index caa6804c8a42a..6299f4524f4f8 100644
--- a/impeller/renderer/backend/metal/surface_mtl.mm
+++ b/impeller/renderer/backend/metal/surface_mtl.mm
@@ -222,7 +222,7 @@ - (void)flutterPrepareForPresent:(nonnull id<MTLCommandBuffer>)commandBuffer;
   return IRect::MakeSize(resolve_texture_->GetSize());
 }
 
-bool SurfaceMTL::PreparePresent() {
+bool SurfaceMTL::PreparePresent() const {
   auto context = context_.lock();
   if (!context) {
     return false;
@@ -265,7 +265,9 @@ - (void)flutterPrepareForPresent:(nonnull id<MTLCommandBuffer>)commandBuffer;
 
 // |Surface|
 bool SurfaceMTL::Present() const {
-  FML_CHECK(prepared_);
+  if (!prepared_) {
+    PreparePresent();
+  }
   auto context = context_.lock();
   if (!context) {
     return false;
diff --git a/shell/gpu/gpu_surface_metal_impeller.mm b/shell/gpu/gpu_surface_metal_impeller.mm
index 1b0f28ec748f0..6c6e4f9e9c17e 100644
--- a/shell/gpu/gpu_surface_metal_impeller.mm
+++ b/shell/gpu/gpu_surface_metal_impeller.mm
@@ -182,7 +182,6 @@
             cull_rect);
         display_list->Dispatch(impeller_dispatcher, sk_cull_rect);
         impeller_dispatcher.FinishRecording();
-        aiks_context->GetContentContext().GetTransientsBuffer().Reset();
         aiks_context->GetContentContext().GetLazyGlyphAtlas()->ResetTextFrames();
         if (reset_host_buffer) {
           aiks_context->GetContentContext().GetTransientsBuffer().Reset();

From 8324a61fddbf8e8aa98b583cc9473262e5a79a32 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Sat, 10 Aug 2024 09:49:26 -0700
Subject: [PATCH 23/37] ++

---
 impeller/aiks/experimental_canvas.cc | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 084a983d78615..dabba34cd1e8d 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -322,14 +322,6 @@ void ExperimentalCanvas::SaveLayer(
     return;
   }
 
-  // // Can we always guarantee that we get a bounds? Does a lack of bounds
-  // // indicate something?
-  // if (!bounds.has_value()) {
-  //   bounds = Rect::MakeSize(render_target_.GetRenderTargetSize());
-  // }
-
-  // SaveLayer is a no-op, depending on the bounds promise. Should/Can DL elide
-  // this?
   if (bounds.has_value() && bounds->IsEmpty()) {
     Save(total_content_depth);
     return;
@@ -358,7 +350,8 @@ void ExperimentalCanvas::SaveLayer(
   auto coverage_limit = maybe_coverage_limit.value();
 
   if (can_distribute_opacity && !backdrop_filter &&
-      Paint::CanApplyOpacityPeephole(paint)) {
+      Paint::CanApplyOpacityPeephole(paint) &&
+      bounds_promise != ContentBoundsPromise::kMayClipContents) {
     Save(total_content_depth);
     transform_stack_.back().distributed_opacity *= paint.color.alpha;
     return;

From cbb19a4458add46aae544746037a7e16a4c79550 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Sat, 10 Aug 2024 10:14:28 -0700
Subject: [PATCH 24/37] bounds adjustment.

---
 impeller/aiks/experimental_canvas.cc | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index dabba34cd1e8d..4efe09aabcf20 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -309,6 +309,11 @@ void ExperimentalCanvas::SaveLayer(
     bool can_distribute_opacity) {
   TRACE_EVENT0("flutter", "Canvas::saveLayer");
 
+  // TODO(jonahwilliams): understand why we sometimes get empty bounds instead of nullopt bounds.
+  if (bounds.has_value() && bounds->IsEmpty()) {
+    bounds = std::nullopt;
+  }
+
   if (!clip_coverage_stack_.HasCoverage()) {
     // The current clip is empty. This means the pass texture won't be
     // visible, so skip it.
@@ -322,11 +327,6 @@ void ExperimentalCanvas::SaveLayer(
     return;
   }
 
-  if (bounds.has_value() && bounds->IsEmpty()) {
-    Save(total_content_depth);
-    return;
-  }
-
   // The maximum coverage of the subpass. Subpasses textures should never
   // extend outside the parent pass texture or the current clip coverage.
   std::optional<Rect> maybe_coverage_limit =

From dc131c0ffad6921b45cd3649f8ac774a46716e30 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Sat, 10 Aug 2024 10:16:39 -0700
Subject: [PATCH 25/37] ++

---
 impeller/aiks/experimental_canvas.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 4efe09aabcf20..b571d247b96fd 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -309,7 +309,8 @@ void ExperimentalCanvas::SaveLayer(
     bool can_distribute_opacity) {
   TRACE_EVENT0("flutter", "Canvas::saveLayer");
 
-  // TODO(jonahwilliams): understand why we sometimes get empty bounds instead of nullopt bounds.
+  // TODO(jonahwilliams): understand why we sometimes get empty bounds instead
+  // of nullopt bounds.
   if (bounds.has_value() && bounds->IsEmpty()) {
     bounds = std::nullopt;
   }

From 5414db387d3297f617e16bccfaa44ff096b22efa Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Sat, 10 Aug 2024 11:50:33 -0700
Subject: [PATCH 26/37] fix advanced blend coverage hint.

---
 impeller/aiks/experimental_canvas.cc | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index b571d247b96fd..ab33859d4a4f7 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -720,12 +720,19 @@ void ExperimentalCanvas::AddRenderEntityToCurrentPass(Entity entity,
         return;
       }
 
+      // The coverage hint tells the rendered Contents which portion of the
+      // rendered output will actually be used, and so we set this to the
+      // current clip coverage (which is the max clip bounds). The contents may
+      // optionally use this hint to avoid unnecessary rendering work.
+      auto element_coverage_hint = entity.GetContents()->GetCoverageHint();
+      entity.GetContents()->SetCoverageHint(Rect::Intersection(
+          element_coverage_hint, clip_coverage_stack_.CurrentClipCoverage()));
+
       FilterInput::Vector inputs = {
           FilterInput::Make(input_texture, entity.GetTransform().Invert()),
           FilterInput::Make(entity.GetContents())};
       auto contents =
           ColorFilterContents::MakeBlend(entity.GetBlendMode(), inputs);
-      contents->SetCoverageHint(entity.GetCoverage());
       entity.SetContents(std::move(contents));
       entity.SetBlendMode(BlendMode::kSource);
     }

From ca34138fb41b3b61823234c35f09ab507051bd26 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Sat, 10 Aug 2024 13:58:44 -0700
Subject: [PATCH 27/37] Add missing return.

---
 impeller/aiks/experimental_canvas.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index ab33859d4a4f7..81f4ec06bcf3c 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -688,6 +688,7 @@ void ExperimentalCanvas::AddRenderEntityToCurrentPass(Entity entity,
                                    .Blend(color, entity.GetBlendMode())
                                    .Premultiply();
       render_target.SetColorAttachment(attachment, 0u);
+      return;
     }
   }
 

From 2c6f55e34ed1c5e7ec69cefda287ea8431aebc21 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Sat, 10 Aug 2024 14:24:34 -0700
Subject: [PATCH 28/37] force final rp construction.

---
 impeller/aiks/experimental_canvas.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 81f4ec06bcf3c..fef77a4890b31 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -865,6 +865,7 @@ bool ExperimentalCanvas::BlitToOnscreen() {
 
 void ExperimentalCanvas::EndReplay() {
   FML_DCHECK(render_passes_.size() == 1u);
+  render_passes_.back().inline_pass_context->GetRenderPass(0);
   render_passes_.back().inline_pass_context->EndPass();
 
   // If requires_readback_ was true, then we rendered to an offscreen texture

From 1236b733c4042225183e7207e5ff7b6952f3bfe5 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Sat, 10 Aug 2024 16:14:16 -0700
Subject: [PATCH 29/37] ++

---
 impeller/aiks/experimental_canvas.cc       | 3 ++-
 impeller/display_list/aiks_dl_unittests.cc | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index fef77a4890b31..f0ab00974f439 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -495,7 +495,8 @@ bool ExperimentalCanvas::Restore() {
         PaintPassDelegate(save_layer_state.paint)
             .CreateContentsForSubpassTarget(
                 lazy_render_pass.inline_pass_context->GetTexture(),
-                transform_stack_.back().transform);
+                Matrix::MakeTranslation(Vector3{-GetGlobalPassPosition()}) *
+                    transform_stack_.back().transform);
 
     lazy_render_pass.inline_pass_context->EndPass();
 
diff --git a/impeller/display_list/aiks_dl_unittests.cc b/impeller/display_list/aiks_dl_unittests.cc
index e8cf7326bcd90..f565b8b6a7214 100644
--- a/impeller/display_list/aiks_dl_unittests.cc
+++ b/impeller/display_list/aiks_dl_unittests.cc
@@ -771,7 +771,7 @@ TEST_P(AiksTest, MatrixSaveLayerFilter) {
   DlPaint paint;
   paint.setColor(DlColor::kBlack());
   builder.DrawPaint(paint);
-  builder.SaveLayer({}, nullptr);
+  builder.SaveLayer(nullptr, nullptr);
   {
     paint.setColor(DlColor::kGreen().withAlpha(255 * 0.5));
     paint.setBlendMode(DlBlendMode::kPlus);

From 630bb36d590649c1e535b8208b374887d20392fb Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 13 Aug 2024 09:57:28 -0700
Subject: [PATCH 30/37] ++

---
 impeller/aiks/experimental_canvas.cc | 25 +++++++++++--------------
 1 file changed, 11 insertions(+), 14 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index f0ab00974f439..add8062768010 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -322,11 +322,12 @@ void ExperimentalCanvas::SaveLayer(
     return;
   }
 
-  auto clip_coverage_back = clip_coverage_stack_.CurrentClipCoverage();
-  if (!clip_coverage_back.has_value()) {
+  auto maybe_current_clip_coverage = clip_coverage_stack_.CurrentClipCoverage();
+  if (!maybe_current_clip_coverage.has_value()) {
     Save(total_content_depth);
     return;
   }
+  auto current_clip_coverage = maybe_current_clip_coverage.value();
 
   // The maximum coverage of the subpass. Subpasses textures should never
   // extend outside the parent pass texture or the current clip coverage.
@@ -335,7 +336,7 @@ void ExperimentalCanvas::SaveLayer(
                            Size(render_passes_.back()
                                     .inline_pass_context->GetTexture()
                                     ->GetSize()))
-          .Intersection(clip_coverage_back.value());
+          .Intersection(current_clip_coverage);
 
   if (!maybe_coverage_limit.has_value()) {
     Save(total_content_depth);
@@ -362,11 +363,8 @@ void ExperimentalCanvas::SaveLayer(
   std::shared_ptr<FilterContents> backdrop_filter_contents;
   Point local_position = {0, 0};
   if (backdrop_filter) {
-    auto current_clip_coverage = clip_coverage_stack_.CurrentClipCoverage();
-    if (current_clip_coverage.has_value()) {
-      local_position =
-          current_clip_coverage->GetOrigin() - GetGlobalPassPosition();
-    }
+    local_position =
+        current_clip_coverage.GetOrigin() - GetGlobalPassPosition();
     EntityPass::BackdropFilterProc backdrop_filter_proc =
         [backdrop_filter = backdrop_filter->Clone()](
             const FilterInput::Ref& input, const Matrix& effect_transform,
@@ -405,13 +403,12 @@ void ExperimentalCanvas::SaveLayer(
   if (backdrop_filter_contents ||
       Entity::IsBlendModeDestructive(paint.blend_mode) || !bounds.has_value()) {
     FML_CHECK(clip_coverage_stack_.HasCoverage());
-    // We should never hit this case as we check the intersection above.
-    // NOLINTBEGIN(bugprone-unchecked-optional-access)
     subpass_coverage =
-        coverage_limit
-            .Intersection(clip_coverage_stack_.CurrentClipCoverage().value())
-            .value();
-    // NOLINTEND(bugprone-unchecked-optional-access)
+        coverage_limit.Intersection(current_clip_coverage).value();
+    // Clip tight bounds, even if clip is flooded.
+    if (bounds.has_value()) {
+      subpass_coverage = coverage_limit.Intersection(bounds.value()).value();
+    }
   } else {
     subpass_coverage = bounds->TransformBounds(GetCurrentTransform());
   }

From 86600bffe064341b2810048e23210af75ebfcff7 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 13 Aug 2024 17:39:47 -0700
Subject: [PATCH 31/37] ++

---
 impeller/display_list/aiks_dl_unittests.cc | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/impeller/display_list/aiks_dl_unittests.cc b/impeller/display_list/aiks_dl_unittests.cc
index f565b8b6a7214..4aa538b26ffdb 100644
--- a/impeller/display_list/aiks_dl_unittests.cc
+++ b/impeller/display_list/aiks_dl_unittests.cc
@@ -748,6 +748,12 @@ TEST_P(AiksTest, MatrixBackdropFilter) {
     DlPaint paint;
     paint.setColor(DlColor::kGreen().withAlpha(0.5 * 255));
     paint.setBlendMode(DlBlendMode::kPlus);
+
+    DlPaint rect_paint;
+    rect_paint.setColor(DlColor::kRed());
+    rect_paint.setStrokeWidth(4);
+    rect_paint.setDrawStyle(DlDrawStyle::kStroke);
+    builder.DrawRect(SkRect::MakeLTRB(0, 0, 300, 300), rect_paint);
     builder.DrawCircle(SkPoint::Make(200, 200), 100, paint);
     // Should render a second circle, centered on the bottom-right-most edge of
     // the circle.

From d11a4acc47f85b3fd4daf738e42902befba888b4 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 14 Aug 2024 13:12:54 -0700
Subject: [PATCH 32/37] fix stroked text.

---
 impeller/aiks/experimental_canvas.cc   | 16 ++++++++++------
 impeller/display_list/dl_dispatcher.cc |  4 ++++
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index add8062768010..5a30c154d6d11 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -309,10 +309,14 @@ void ExperimentalCanvas::SaveLayer(
     bool can_distribute_opacity) {
   TRACE_EVENT0("flutter", "Canvas::saveLayer");
 
-  // TODO(jonahwilliams): understand why we sometimes get empty bounds instead
-  // of nullopt bounds.
+  // Empty bounds on a save layer that contains a BDF should be treated as
+  // unbounded.
   if (bounds.has_value() && bounds->IsEmpty()) {
-    bounds = std::nullopt;
+    if (backdrop_filter != nullptr) {
+      bounds = std::nullopt;
+    } else {
+      Save(total_content_depth);
+    }
   }
 
   if (!clip_coverage_stack_.HasCoverage()) {
@@ -403,11 +407,11 @@ void ExperimentalCanvas::SaveLayer(
   if (backdrop_filter_contents ||
       Entity::IsBlendModeDestructive(paint.blend_mode) || !bounds.has_value()) {
     FML_CHECK(clip_coverage_stack_.HasCoverage());
-    subpass_coverage =
-        coverage_limit.Intersection(current_clip_coverage).value();
+    subpass_coverage = coverage_limit;
     // Clip tight bounds, even if clip is flooded.
     if (bounds.has_value()) {
-      subpass_coverage = coverage_limit.Intersection(bounds.value()).value();
+      subpass_coverage =
+          coverage_limit.Intersection(bounds.value()).value_or(bounds.value());
     }
   } else {
     subpass_coverage = bounds->TransformBounds(GetCurrentTransform());
diff --git a/impeller/display_list/dl_dispatcher.cc b/impeller/display_list/dl_dispatcher.cc
index 787beab7020f2..1ab37505a4640 100644
--- a/impeller/display_list/dl_dispatcher.cc
+++ b/impeller/display_list/dl_dispatcher.cc
@@ -1102,6 +1102,7 @@ void DlDispatcherBase::drawTextBlob(const sk_sp<SkTextBlob> blob,
   UNIMPLEMENTED;
 }
 
+// |flutter::DlOpReceiver|
 void DlDispatcherBase::drawTextFrame(
     const std::shared_ptr<TextFrame>& text_frame,
     SkScalar x,
@@ -1319,8 +1320,11 @@ void TextFrameDispatcher::drawDisplayList(
     SkScalar opacity) {
   [[maybe_unused]] size_t stack_depth = stack_.size();
   save();
+  Paint old_paint = paint_;
+  paint_ = Paint{};
   display_list->Dispatch(*this);
   restore();
+  paint_ = old_paint;
   FML_DCHECK(stack_depth == stack_.size());
 }
 

From c3a64cf80a2c645fd1a8ddb4bb91c2725939a0fc Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 14 Aug 2024 18:32:33 -0700
Subject: [PATCH 33/37] adjust more things.

---
 impeller/aiks/experimental_canvas.cc   | 9 ++-------
 impeller/display_list/dl_dispatcher.cc | 8 ++++++++
 impeller/entity/entity.cc              | 1 +
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 5a30c154d6d11..c7973c4260c02 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -309,14 +309,9 @@ void ExperimentalCanvas::SaveLayer(
     bool can_distribute_opacity) {
   TRACE_EVENT0("flutter", "Canvas::saveLayer");
 
-  // Empty bounds on a save layer that contains a BDF should be treated as
-  // unbounded.
   if (bounds.has_value() && bounds->IsEmpty()) {
-    if (backdrop_filter != nullptr) {
-      bounds = std::nullopt;
-    } else {
-      Save(total_content_depth);
-    }
+    Save(total_content_depth);
+    return;
   }
 
   if (!clip_coverage_stack_.HasCoverage()) {
diff --git a/impeller/display_list/dl_dispatcher.cc b/impeller/display_list/dl_dispatcher.cc
index 1ab37505a4640..60df1aad52ee3 100644
--- a/impeller/display_list/dl_dispatcher.cc
+++ b/impeller/display_list/dl_dispatcher.cc
@@ -604,6 +604,14 @@ void DlDispatcherBase::saveLayer(const SkRect& bounds,
     impeller_bounds = skia_conversions::ToRect(bounds);
   }
 
+  // Empty bounds on a save layer that contains a BDF or destructive blend
+  // should be treated as unbounded. All other empty bounds can be skipped.
+  if (impeller_bounds.has_value() && impeller_bounds->IsEmpty() &&
+      (backdrop != nullptr ||
+       Entity::IsBlendModeDestructive(paint.blend_mode))) {
+    impeller_bounds = std::nullopt;
+  }
+
   GetCanvas().SaveLayer(paint, impeller_bounds, ToImageFilter(backdrop),
                         promise, total_content_depth,
                         options.can_distribute_opacity());
diff --git a/impeller/entity/entity.cc b/impeller/entity/entity.cc
index cb336892d3a61..29d4c7445894e 100644
--- a/impeller/entity/entity.cc
+++ b/impeller/entity/entity.cc
@@ -164,6 +164,7 @@ bool Entity::IsBlendModeDestructive(BlendMode blend_mode) {
     case BlendMode::kDestinationATop:
     case BlendMode::kXor:
     case BlendMode::kModulate:
+    case BlendMode::kDestinationOver:
       return true;
     default:
       return false;

From 02b7834cf81bcf36230656244857c606be96963d Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 14 Aug 2024 18:34:01 -0700
Subject: [PATCH 34/37] ++

---
 impeller/entity/entity.cc | 1 -
 1 file changed, 1 deletion(-)

diff --git a/impeller/entity/entity.cc b/impeller/entity/entity.cc
index 29d4c7445894e..cb336892d3a61 100644
--- a/impeller/entity/entity.cc
+++ b/impeller/entity/entity.cc
@@ -164,7 +164,6 @@ bool Entity::IsBlendModeDestructive(BlendMode blend_mode) {
     case BlendMode::kDestinationATop:
     case BlendMode::kXor:
     case BlendMode::kModulate:
-    case BlendMode::kDestinationOver:
       return true;
     default:
       return false;

From 3899c5824bdc4841ae19b293728b8b98fbfbf215 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 14 Aug 2024 20:07:16 -0700
Subject: [PATCH 35/37] ++

---
 impeller/aiks/canvas.cc                | 3 ++-
 impeller/aiks/canvas.h                 | 3 ++-
 impeller/aiks/experimental_canvas.cc   | 5 +++--
 impeller/aiks/experimental_canvas.h    | 3 ++-
 impeller/display_list/dl_dispatcher.cc | 3 ++-
 5 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/impeller/aiks/canvas.cc b/impeller/aiks/canvas.cc
index 2b709fdc83159..37be4bfd7aa23 100644
--- a/impeller/aiks/canvas.cc
+++ b/impeller/aiks/canvas.cc
@@ -807,7 +807,8 @@ void Canvas::SaveLayer(const Paint& paint,
                        const std::shared_ptr<ImageFilter>& backdrop_filter,
                        ContentBoundsPromise bounds_promise,
                        uint32_t total_content_depth,
-                       bool can_distribute_opacity) {
+                       bool can_distribute_opacity,
+                       bool bounds_from_caller) {
   if (can_distribute_opacity && !backdrop_filter &&
       Paint::CanApplyOpacityPeephole(paint) &&
       bounds_promise != ContentBoundsPromise::kMayClipContents) {
diff --git a/impeller/aiks/canvas.h b/impeller/aiks/canvas.h
index e5bdc379b0622..834b3d118e1e2 100644
--- a/impeller/aiks/canvas.h
+++ b/impeller/aiks/canvas.h
@@ -77,7 +77,8 @@ class Canvas {
       const std::shared_ptr<ImageFilter>& backdrop_filter = nullptr,
       ContentBoundsPromise bounds_promise = ContentBoundsPromise::kUnknown,
       uint32_t total_content_depth = kMaxDepth,
-      bool can_distribute_opacity = false);
+      bool can_distribute_opacity = false,
+      bool bounds_from_caller = false);
 
   virtual bool Restore();
 
diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index c7973c4260c02..839b2d5e35877 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -306,7 +306,8 @@ void ExperimentalCanvas::SaveLayer(
     const std::shared_ptr<ImageFilter>& backdrop_filter,
     ContentBoundsPromise bounds_promise,
     uint32_t total_content_depth,
-    bool can_distribute_opacity) {
+    bool can_distribute_opacity,
+    bool bounds_from_caller) {
   TRACE_EVENT0("flutter", "Canvas::saveLayer");
 
   if (bounds.has_value() && bounds->IsEmpty()) {
@@ -404,7 +405,7 @@ void ExperimentalCanvas::SaveLayer(
     FML_CHECK(clip_coverage_stack_.HasCoverage());
     subpass_coverage = coverage_limit;
     // Clip tight bounds, even if clip is flooded.
-    if (bounds.has_value()) {
+    if (bounds.has_value() && bounds_from_caller) {
       subpass_coverage =
           coverage_limit.Intersection(bounds.value()).value_or(bounds.value());
     }
diff --git a/impeller/aiks/experimental_canvas.h b/impeller/aiks/experimental_canvas.h
index debb4baf088fc..8ec5e18b7c1e2 100644
--- a/impeller/aiks/experimental_canvas.h
+++ b/impeller/aiks/experimental_canvas.h
@@ -71,7 +71,8 @@ class ExperimentalCanvas : public Canvas {
                  const std::shared_ptr<ImageFilter>& backdrop_filter,
                  ContentBoundsPromise bounds_promise,
                  uint32_t total_content_depth,
-                 bool can_distribute_opacity) override;
+                 bool can_distribute_opacity,
+                 bool bounds_from_caller) override;
 
   bool Restore() override;
 
diff --git a/impeller/display_list/dl_dispatcher.cc b/impeller/display_list/dl_dispatcher.cc
index 60df1aad52ee3..eda382ba07de8 100644
--- a/impeller/display_list/dl_dispatcher.cc
+++ b/impeller/display_list/dl_dispatcher.cc
@@ -614,7 +614,8 @@ void DlDispatcherBase::saveLayer(const SkRect& bounds,
 
   GetCanvas().SaveLayer(paint, impeller_bounds, ToImageFilter(backdrop),
                         promise, total_content_depth,
-                        options.can_distribute_opacity());
+                        options.can_distribute_opacity(),
+                        options.bounds_from_caller());
 }
 
 // |flutter::DlOpReceiver|

From 3e21b07169ceb80a420e9275d37a5834934f31cd Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 15 Aug 2024 08:32:34 -0700
Subject: [PATCH 36/37] remove incorrect clip

---
 impeller/aiks/experimental_canvas.cc | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/impeller/aiks/experimental_canvas.cc b/impeller/aiks/experimental_canvas.cc
index 839b2d5e35877..b9cd19a12afcd 100644
--- a/impeller/aiks/experimental_canvas.cc
+++ b/impeller/aiks/experimental_canvas.cc
@@ -402,13 +402,12 @@ void ExperimentalCanvas::SaveLayer(
   Rect subpass_coverage;
   if (backdrop_filter_contents ||
       Entity::IsBlendModeDestructive(paint.blend_mode) || !bounds.has_value()) {
-    FML_CHECK(clip_coverage_stack_.HasCoverage());
     subpass_coverage = coverage_limit;
-    // Clip tight bounds, even if clip is flooded.
-    if (bounds.has_value() && bounds_from_caller) {
-      subpass_coverage =
-          coverage_limit.Intersection(bounds.value()).value_or(bounds.value());
-    }
+    // TODO(jonahwilliams): if we have tight bounds we should be able to reduce
+    // this size here. if (bounds.has_value() && bounds_from_caller) {
+    //   subpass_coverage =
+    //       coverage_limit.Intersection(bounds.value()).value_or(bounds.value());
+    // }
   } else {
     subpass_coverage = bounds->TransformBounds(GetCurrentTransform());
   }

From c2b89385d867b36595aa40a4a5f0ec0739cebf00 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Thu, 15 Aug 2024 08:39:51 -0700
Subject: [PATCH 37/37] remove test opt outs.

---
 impeller/aiks/aiks_unittests.cc               | 119 +++++++++---------
 .../gpu_surface_metal_impeller_unittests.mm   |  81 ++++++------
 2 files changed, 99 insertions(+), 101 deletions(-)

diff --git a/impeller/aiks/aiks_unittests.cc b/impeller/aiks/aiks_unittests.cc
index 828904bee71eb..2919c78604e4a 100644
--- a/impeller/aiks/aiks_unittests.cc
+++ b/impeller/aiks/aiks_unittests.cc
@@ -242,66 +242,65 @@ TEST_P(AiksTest, DrawRectAbsorbsClears) {
   ASSERT_EQ(render_pass->GetCommands().size(), 0llu);
 }
 
-// TEST_P(AiksTest, DrawRectAbsorbsClearsNegativeRRect) {
-//   Canvas canvas;
-//   canvas.DrawRRect(Rect::MakeXYWH(0, 0, 300, 300), {5.0, 5.0},
-//                    {.color = Color::Red(), .blend_mode =
-//                    BlendMode::kSource});
-//   canvas.DrawRRect(Rect::MakeXYWH(0, 0, 300, 300), {5.0, 5.0},
-//                    {.color = Color::CornflowerBlue().WithAlpha(0.75),
-//                     .blend_mode = BlendMode::kSourceOver});
-
-//   std::shared_ptr<ContextSpy> spy = ContextSpy::Make();
-//   Picture picture = canvas.EndRecordingAsPicture();
-//   std::shared_ptr<Context> real_context = GetContext();
-//   std::shared_ptr<ContextMock> mock_context = spy->MakeContext(real_context);
-//   AiksContext renderer(mock_context, nullptr);
-//   std::shared_ptr<Image> image = picture.ToImage(renderer, {300, 300});
-
-//   ASSERT_EQ(spy->render_passes_.size(), 1llu);
-//   std::shared_ptr<RenderPass> render_pass = spy->render_passes_[0];
-//   ASSERT_EQ(render_pass->GetCommands().size(), 2llu);
-// }
-
-// TEST_P(AiksTest, DrawRectAbsorbsClearsNegativeRotation) {
-//   Canvas canvas;
-//   canvas.Translate(Vector3(150.0, 150.0, 0.0));
-//   canvas.Rotate(Degrees(45.0));
-//   canvas.Translate(Vector3(-150.0, -150.0, 0.0));
-//   canvas.DrawRect(Rect::MakeXYWH(0, 0, 300, 300),
-//                   {.color = Color::Red(), .blend_mode = BlendMode::kSource});
-
-//   std::shared_ptr<ContextSpy> spy = ContextSpy::Make();
-//   Picture picture = canvas.EndRecordingAsPicture();
-//   std::shared_ptr<Context> real_context = GetContext();
-//   std::shared_ptr<ContextMock> mock_context = spy->MakeContext(real_context);
-//   AiksContext renderer(mock_context, nullptr);
-//   std::shared_ptr<Image> image = picture.ToImage(renderer, {300, 300});
-
-//   ASSERT_EQ(spy->render_passes_.size(), 1llu);
-//   std::shared_ptr<RenderPass> render_pass = spy->render_passes_[0];
-//   ASSERT_EQ(render_pass->GetCommands().size(), 1llu);
-// }
-
-// TEST_P(AiksTest, DrawRectAbsorbsClearsNegative) {
-//   Canvas canvas;
-//   canvas.DrawRect(Rect::MakeXYWH(0, 0, 300, 300),
-//                   {.color = Color::Red(), .blend_mode = BlendMode::kSource});
-//   canvas.DrawRect(Rect::MakeXYWH(0, 0, 300, 300),
-//                   {.color = Color::CornflowerBlue().WithAlpha(0.75),
-//                    .blend_mode = BlendMode::kSourceOver});
-
-//   std::shared_ptr<ContextSpy> spy = ContextSpy::Make();
-//   Picture picture = canvas.EndRecordingAsPicture();
-//   std::shared_ptr<Context> real_context = GetContext();
-//   std::shared_ptr<ContextMock> mock_context = spy->MakeContext(real_context);
-//   AiksContext renderer(mock_context, nullptr);
-//   std::shared_ptr<Image> image = picture.ToImage(renderer, {301, 301});
-
-//   ASSERT_EQ(spy->render_passes_.size(), 1llu);
-//   std::shared_ptr<RenderPass> render_pass = spy->render_passes_[0];
-//   ASSERT_EQ(render_pass->GetCommands().size(), 2llu);
-// }
+TEST_P(AiksTest, DrawRectAbsorbsClearsNegativeRRect) {
+  Canvas canvas;
+  canvas.DrawRRect(Rect::MakeXYWH(0, 0, 300, 300), {5.0, 5.0},
+                   {.color = Color::Red(), .blend_mode = BlendMode::kSource});
+  canvas.DrawRRect(Rect::MakeXYWH(0, 0, 300, 300), {5.0, 5.0},
+                   {.color = Color::CornflowerBlue().WithAlpha(0.75),
+                    .blend_mode = BlendMode::kSourceOver});
+
+  std::shared_ptr<ContextSpy> spy = ContextSpy::Make();
+  Picture picture = canvas.EndRecordingAsPicture();
+  std::shared_ptr<Context> real_context = GetContext();
+  std::shared_ptr<ContextMock> mock_context = spy->MakeContext(real_context);
+  AiksContext renderer(mock_context, nullptr);
+  std::shared_ptr<Image> image = picture.ToImage(renderer, {300, 300});
+
+  ASSERT_EQ(spy->render_passes_.size(), 1llu);
+  std::shared_ptr<RenderPass> render_pass = spy->render_passes_[0];
+  ASSERT_EQ(render_pass->GetCommands().size(), 2llu);
+}
+
+TEST_P(AiksTest, DrawRectAbsorbsClearsNegativeRotation) {
+  Canvas canvas;
+  canvas.Translate(Vector3(150.0, 150.0, 0.0));
+  canvas.Rotate(Degrees(45.0));
+  canvas.Translate(Vector3(-150.0, -150.0, 0.0));
+  canvas.DrawRect(Rect::MakeXYWH(0, 0, 300, 300),
+                  {.color = Color::Red(), .blend_mode = BlendMode::kSource});
+
+  std::shared_ptr<ContextSpy> spy = ContextSpy::Make();
+  Picture picture = canvas.EndRecordingAsPicture();
+  std::shared_ptr<Context> real_context = GetContext();
+  std::shared_ptr<ContextMock> mock_context = spy->MakeContext(real_context);
+  AiksContext renderer(mock_context, nullptr);
+  std::shared_ptr<Image> image = picture.ToImage(renderer, {300, 300});
+
+  ASSERT_EQ(spy->render_passes_.size(), 1llu);
+  std::shared_ptr<RenderPass> render_pass = spy->render_passes_[0];
+  ASSERT_EQ(render_pass->GetCommands().size(), 1llu);
+}
+
+TEST_P(AiksTest, DrawRectAbsorbsClearsNegative) {
+  Canvas canvas;
+  canvas.DrawRect(Rect::MakeXYWH(0, 0, 300, 300),
+                  {.color = Color::Red(), .blend_mode = BlendMode::kSource});
+  canvas.DrawRect(Rect::MakeXYWH(0, 0, 300, 300),
+                  {.color = Color::CornflowerBlue().WithAlpha(0.75),
+                   .blend_mode = BlendMode::kSourceOver});
+
+  std::shared_ptr<ContextSpy> spy = ContextSpy::Make();
+  Picture picture = canvas.EndRecordingAsPicture();
+  std::shared_ptr<Context> real_context = GetContext();
+  std::shared_ptr<ContextMock> mock_context = spy->MakeContext(real_context);
+  AiksContext renderer(mock_context, nullptr);
+  std::shared_ptr<Image> image = picture.ToImage(renderer, {301, 301});
+
+  ASSERT_EQ(spy->render_passes_.size(), 1llu);
+  std::shared_ptr<RenderPass> render_pass = spy->render_passes_[0];
+  ASSERT_EQ(render_pass->GetCommands().size(), 2llu);
+}
 
 TEST_P(AiksTest, ClipRectElidesNoOpClips) {
   Canvas canvas(Rect::MakeXYWH(0, 0, 100, 100));
diff --git a/shell/gpu/gpu_surface_metal_impeller_unittests.mm b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
index 94bde0eb25fc5..a5927ff035783 100644
--- a/shell/gpu/gpu_surface_metal_impeller_unittests.mm
+++ b/shell/gpu/gpu_surface_metal_impeller_unittests.mm
@@ -97,63 +97,62 @@ GPUCAMetalLayerHandle GetCAMetalLayer(const SkISize& frame_info) const override
   ASSERT_TRUE(frame->Submit());
 }
 
-// TESTING!
-// TEST(GPUSurfaceMetalImpeller, ResetHostBufferBasedOnFrameBoundary) {
-//   auto delegate = std::make_shared<TestGPUSurfaceMetalDelegate>();
-//   delegate->SetDevice();
+TEST(GPUSurfaceMetalImpeller, ResetHostBufferBasedOnFrameBoundary) {
+  auto delegate = std::make_shared<TestGPUSurfaceMetalDelegate>();
+  delegate->SetDevice();
 
-//   auto context = CreateImpellerContext();
-//   std::unique_ptr<Surface> surface =
-//       std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
+  auto context = CreateImpellerContext();
+  std::unique_ptr<Surface> surface =
+      std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
 
-//   ASSERT_TRUE(surface->IsValid());
+  ASSERT_TRUE(surface->IsValid());
 
-//   auto& host_buffer = surface->GetAiksContext()->GetContentContext().GetTransientsBuffer();
+  auto& host_buffer = surface->GetAiksContext()->GetContentContext().GetTransientsBuffer();
 
-//   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
+  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
 
-//   auto frame = surface->AcquireFrame(SkISize::Make(100, 100));
-//   frame->set_submit_info({.frame_boundary = false});
+  auto frame = surface->AcquireFrame(SkISize::Make(100, 100));
+  frame->set_submit_info({.frame_boundary = false});
 
-//   ASSERT_TRUE(frame->Submit());
-//   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
+  ASSERT_TRUE(frame->Submit());
+  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 0u);
 
-//   frame = surface->AcquireFrame(SkISize::Make(100, 100));
-//   frame->set_submit_info({.frame_boundary = true});
+  frame = surface->AcquireFrame(SkISize::Make(100, 100));
+  frame->set_submit_info({.frame_boundary = true});
 
-//   ASSERT_TRUE(frame->Submit());
-//   EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
-// }
+  ASSERT_TRUE(frame->Submit());
+  EXPECT_EQ(host_buffer.GetStateForTest().current_frame, 1u);
+}
 
-// #ifdef IMPELLER_DEBUG
-// TEST(GPUSurfaceMetalImpeller, CreatesImpellerCaptureScope) {
-//   auto delegate = std::make_shared<TestGPUSurfaceMetalDelegate>();
-//   delegate->SetDevice();
+#ifdef IMPELLER_DEBUG
+TEST(GPUSurfaceMetalImpeller, CreatesImpellerCaptureScope) {
+  auto delegate = std::make_shared<TestGPUSurfaceMetalDelegate>();
+  delegate->SetDevice();
 
-//   auto context = CreateImpellerContext();
+  auto context = CreateImpellerContext();
 
-//   EXPECT_FALSE(context->GetCaptureManager()->CaptureScopeActive());
+  EXPECT_FALSE(context->GetCaptureManager()->CaptureScopeActive());
 
-//   std::unique_ptr<Surface> surface =
-//       std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
-//   auto frame_1 = surface->AcquireFrame(SkISize::Make(100, 100));
-//   frame_1->set_submit_info({.frame_boundary = false});
+  std::unique_ptr<Surface> surface =
+      std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
+  auto frame_1 = surface->AcquireFrame(SkISize::Make(100, 100));
+  frame_1->set_submit_info({.frame_boundary = false});
 
-//   EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
+  EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
 
-//   std::unique_ptr<Surface> surface_2 =
-//       std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
-//   auto frame_2 = surface->AcquireFrame(SkISize::Make(100, 100));
-//   frame_2->set_submit_info({.frame_boundary = true});
+  std::unique_ptr<Surface> surface_2 =
+      std::make_unique<GPUSurfaceMetalImpeller>(delegate.get(), context);
+  auto frame_2 = surface->AcquireFrame(SkISize::Make(100, 100));
+  frame_2->set_submit_info({.frame_boundary = true});
 
-//   EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
+  EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
 
-//   ASSERT_TRUE(frame_1->Submit());
-//   EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
-//   ASSERT_TRUE(frame_2->Submit());
-//   EXPECT_FALSE(context->GetCaptureManager()->CaptureScopeActive());
-// }
-// #endif  // IMPELLER_DEBUG
+  ASSERT_TRUE(frame_1->Submit());
+  EXPECT_TRUE(context->GetCaptureManager()->CaptureScopeActive());
+  ASSERT_TRUE(frame_2->Submit());
+  EXPECT_FALSE(context->GetCaptureManager()->CaptureScopeActive());
+}
+#endif  // IMPELLER_DEBUG
 
 }  // namespace testing
 }  // namespace flutter