[Impeller] Cache render target texture allocations across frames.

ci/licenses_golden/excluded_files

@@ -128,12 +128,14 @@
 ../../../flutter/impeller/compiler/README.md
 ../../../flutter/impeller/compiler/compiler_unittests.cc
 ../../../flutter/impeller/compiler/switches_unittests.cc
+../../../flutter/impeller/core/allocator_unittests.cc
 ../../../flutter/impeller/display_list/dl_unittests.cc
 ../../../flutter/impeller/display_list/skia_conversions_unittests.cc
 ../../../flutter/impeller/docs
 ../../../flutter/impeller/entity/contents/filters/inputs/filter_input_unittests.cc
 ../../../flutter/impeller/entity/entity_unittests.cc
 ../../../flutter/impeller/entity/geometry/geometry_unittests.cc
+../../../flutter/impeller/entity/render_target_cache_unittests.cc
 ../../../flutter/impeller/fixtures
 ../../../flutter/impeller/geometry/README.md
 ../../../flutter/impeller/geometry/geometry_unittests.cc

ci/licenses_golden/licenses_flutter

@@ -1271,6 +1271,8 @@ ORIGIN: ../../../flutter/impeller/entity/geometry/vertices_geometry.cc + ../../.
 ORIGIN: ../../../flutter/impeller/entity/geometry/vertices_geometry.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/inline_pass_context.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/inline_pass_context.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/impeller/entity/render_target_cache.cc + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/impeller/entity/render_target_cache.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/shaders/blending/advanced_blend.glsl + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/shaders/blending/advanced_blend.vert + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/shaders/blending/advanced_blend_color.frag + ../../../flutter/LICENSE
@@ -3995,6 +3997,8 @@ FILE: ../../../flutter/impeller/entity/geometry/vertices_geometry.cc
 FILE: ../../../flutter/impeller/entity/geometry/vertices_geometry.h
 FILE: ../../../flutter/impeller/entity/inline_pass_context.cc
 FILE: ../../../flutter/impeller/entity/inline_pass_context.h
+FILE: ../../../flutter/impeller/entity/render_target_cache.cc
+FILE: ../../../flutter/impeller/entity/render_target_cache.h
 FILE: ../../../flutter/impeller/entity/shaders/blending/advanced_blend.glsl
 FILE: ../../../flutter/impeller/entity/shaders/blending/advanced_blend.vert
 FILE: ../../../flutter/impeller/entity/shaders/blending/advanced_blend_color.frag

impeller/BUILD.gn

@@ -77,6 +77,7 @@ impeller_component("impeller_unittests") {
     "base:base_unittests",
     "blobcat:blobcat_unittests",
     "compiler:compiler_unittests",
+    "core:allocator_unittests",
     "display_list:skia_conversions_unittests",
     "geometry:geometry_unittests",
     "runtime_stage:runtime_stage_unittests",
@@ -89,6 +90,7 @@ impeller_component("impeller_unittests") {
       "aiks:aiks_unittests",
       "display_list:display_list_unittests",
       "entity:entity_unittests",
+      "entity:render_target_cache_unittests",
       "fixtures",
       "geometry:geometry_unittests",
       "image:image_unittests",

impeller/aiks/picture.cc

@@ -54,10 +54,15 @@ std::shared_ptr<Texture> Picture::RenderToTexture(
   // This texture isn't host visible, but we might want to add host visible
   // features to Image someday.
   auto impeller_context = context.GetContext();
+  // Do not use the render target cache as the lifecycle of this texture
+  // will outlive a particular frame.
+  RenderTargetAllocator render_target_allocator =
+      RenderTargetAllocator(impeller_context->GetResourceAllocator());
   RenderTarget target;
   if (impeller_context->GetCapabilities()->SupportsOffscreenMSAA()) {
     target = RenderTarget::CreateOffscreenMSAA(
         *impeller_context,        // context
+        render_target_allocator,  // allocator
         size,                     // size
         "Picture Snapshot MSAA",  // label
         RenderTarget::
@@ -70,6 +75,7 @@ std::shared_ptr<Texture> Picture::RenderToTexture(
   } else {
     target = RenderTarget::CreateOffscreen(
         *impeller_context,                           // context
+        render_target_allocator,                     // allocator
         size,                                        // size
         "Picture Snapshot",                          // label
         RenderTarget::kDefaultColorAttachmentConfig  // color_attachment_config

impeller/core/BUILD.gn

@@ -49,3 +49,15 @@ impeller_component("core") {
     "//flutter/fml",
   ]
 }
+
+impeller_component("allocator_unittests") {
+  testonly = true
+
+  sources = [ "allocator_unittests.cc" ]
+
+  deps = [
+    ":core",
+    "../geometry",
+    "//flutter/testing:testing_lib",
+  ]
+}

impeller/core/allocator.cc

@@ -6,6 +6,7 @@
 
 #include "impeller/base/validation.h"
 #include "impeller/core/device_buffer.h"
+#include "impeller/core/formats.h"
 #include "impeller/core/range.h"
 
 namespace impeller {
@@ -57,10 +58,10 @@ std::shared_ptr<Texture> Allocator::CreateTexture(
   return OnCreateTexture(desc);
 }
 
+void Allocator::DidAcquireSurfaceFrame() {}
+
 uint16_t Allocator::MinimumBytesPerRow(PixelFormat format) const {
   return BytesPerPixelForPixelFormat(format);
 }
 
-void Allocator::DidAcquireSurfaceFrame() {}
-
 }  // namespace impeller

impeller/core/allocator.h

@@ -9,7 +9,9 @@
 #include "flutter/fml/macros.h"
 #include "flutter/fml/mapping.h"
 #include "impeller/core/device_buffer_descriptor.h"
+#include "impeller/core/texture.h"
 #include "impeller/core/texture_descriptor.h"
+#include "impeller/geometry/size.h"
 
 namespace impeller {
 

impeller/core/allocator_unittests.cc

@@ -0,0 +1,83 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <memory>
+#include "flutter/testing/testing.h"
+#include "impeller/core/allocator.h"
+#include "impeller/core/formats.h"
+#include "impeller/core/texture_descriptor.h"
+#include "impeller/geometry/size.h"
+#include "impeller/renderer/testing/mocks.h"
+
+namespace impeller {
+namespace testing {
+
+TEST(AllocatorTest, TextureDescriptorCompatibility) {
+  // Size.
+  {
+    TextureDescriptor desc_a = {.size = ISize(100, 100)};
+    TextureDescriptor desc_b = {.size = ISize(100, 100)};
+    TextureDescriptor desc_c = {.size = ISize(101, 100)};
+
+    ASSERT_EQ(desc_a, desc_b);
+    ASSERT_NE(desc_a, desc_c);
+  }
+  // Storage Mode.
+  {
+    TextureDescriptor desc_a = {.storage_mode = StorageMode::kDevicePrivate};
+    TextureDescriptor desc_b = {.storage_mode = StorageMode::kDevicePrivate};
+    TextureDescriptor desc_c = {.storage_mode = StorageMode::kHostVisible};
+
+    ASSERT_EQ(desc_a, desc_b);
+    ASSERT_NE(desc_a, desc_c);
+  }
+  // Format.
+  {
+    TextureDescriptor desc_a = {.format = PixelFormat::kR8G8B8A8UNormInt};
+    TextureDescriptor desc_b = {.format = PixelFormat::kR8G8B8A8UNormInt};
+    TextureDescriptor desc_c = {.format = PixelFormat::kB10G10R10A10XR};
+
+    ASSERT_EQ(desc_a, desc_b);
+    ASSERT_NE(desc_a, desc_c);
+  }
+  // Sample Count.
+  {
+    TextureDescriptor desc_a = {.sample_count = SampleCount::kCount4};
+    TextureDescriptor desc_b = {.sample_count = SampleCount::kCount4};
+    TextureDescriptor desc_c = {.sample_count = SampleCount::kCount1};
+
+    ASSERT_EQ(desc_a, desc_b);
+    ASSERT_NE(desc_a, desc_c);
+  }
+  // Sample Count.
+  {
+    TextureDescriptor desc_a = {.type = TextureType::kTexture2DMultisample};
+    TextureDescriptor desc_b = {.type = TextureType::kTexture2DMultisample};
+    TextureDescriptor desc_c = {.type = TextureType::kTexture2D};
+
+    ASSERT_EQ(desc_a, desc_b);
+    ASSERT_NE(desc_a, desc_c);
+  }
+  // Compression.
+  {
+    TextureDescriptor desc_a = {.compression_type = CompressionType::kLossless};
+    TextureDescriptor desc_b = {.compression_type = CompressionType::kLossless};
+    TextureDescriptor desc_c = {.compression_type = CompressionType::kLossy};
+
+    ASSERT_EQ(desc_a, desc_b);
+    ASSERT_NE(desc_a, desc_c);
+  }
+  // Mip Count.
+  {
+    TextureDescriptor desc_a = {.mip_count = 1};
+    TextureDescriptor desc_b = {.mip_count = 1};
+    TextureDescriptor desc_c = {.mip_count = 4};
+
+    ASSERT_EQ(desc_a, desc_b);
+    ASSERT_NE(desc_a, desc_c);
+  }
+}
+
+}  // namespace testing
+}  // namespace impeller

impeller/core/texture_descriptor.h

@@ -66,6 +66,21 @@ struct TextureDescriptor {
     return IsMultisampleCapable(type) ? count > 1 : count == 1;
   }
 
+  constexpr bool operator==(const TextureDescriptor& other) const {
+    return size == other.size &&                          //
+           storage_mode == other.storage_mode &&          //
+           format == other.format &&                      //
+           usage == other.usage &&                        //
+           sample_count == other.sample_count &&          //
+           type == other.type &&                          //
+           compression_type == other.compression_type &&  //
+           mip_count == other.mip_count;
+  }
+
+  constexpr bool operator!=(const TextureDescriptor& other) const {
+    return !(*this == other);
+  }
+
   constexpr bool IsValid() const {
     return format != PixelFormat::kUnknown &&  //
            size.IsPositive() &&                //

impeller/entity/BUILD.gn

@@ -242,6 +242,8 @@ impeller_component("entity") {
     "geometry/vertices_geometry.h",
     "inline_pass_context.cc",
     "inline_pass_context.h",
+    "render_target_cache.cc",
+    "render_target_cache.h",
   ]
 
   if (impeller_debug) {
@@ -282,3 +284,14 @@ impeller_component("entity_unittests") {
     "../playground:playground_test",
   ]
 }
+
+impeller_component("render_target_cache_unittests") {
+  testonly = true
+
+  sources = [ "render_target_cache_unittests.cc" ]
+
+  deps = [
+    ":entity",
+    "//flutter/testing:testing_lib",
+  ]
+}

impeller/entity/contents/content_context.cc

@@ -10,6 +10,7 @@
 #include "impeller/base/strings.h"
 #include "impeller/core/formats.h"
 #include "impeller/entity/entity.h"
+#include "impeller/entity/render_target_cache.h"
 #include "impeller/renderer/command_buffer.h"
 #include "impeller/renderer/pipeline_library.h"
 #include "impeller/renderer/render_pass.h"
@@ -162,7 +163,9 @@ ContentContext::ContentContext(std::shared_ptr<Context> context)
     : context_(std::move(context)),
       lazy_glyph_atlas_(std::make_shared<LazyGlyphAtlas>()),
       tessellator_(std::make_shared<Tessellator>()),
-      scene_context_(std::make_shared<scene::SceneContext>(context_)) {
+      scene_context_(std::make_shared<scene::SceneContext>(context_)),
+      render_target_cache_(std::make_shared<RenderTargetCache>(
+          context_->GetResourceAllocator())) {
   if (!context_ || !context_->IsValid()) {
     return;
   }
@@ -359,7 +362,8 @@ std::shared_ptr<Texture> ContentContext::MakeSubpass(
   RenderTarget subpass_target;
   if (context->GetCapabilities()->SupportsOffscreenMSAA() && msaa_enabled) {
     subpass_target = RenderTarget::CreateOffscreenMSAA(
-        *context, texture_size, SPrintF("%s Offscreen", label.c_str()),
+        *context, *GetRenderTargetCache().get(), texture_size,
+        SPrintF("%s Offscreen", label.c_str()),
         RenderTarget::kDefaultColorAttachmentConfigMSAA  //
 #ifndef FML_OS_ANDROID  // Reduce PSO variants for Vulkan.
         ,
@@ -368,7 +372,8 @@ std::shared_ptr<Texture> ContentContext::MakeSubpass(
     );
   } else {
     subpass_target = RenderTarget::CreateOffscreen(
-        *context, texture_size, SPrintF("%s Offscreen", label.c_str()),
+        *context, *GetRenderTargetCache().get(), texture_size,
+        SPrintF("%s Offscreen", label.c_str()),
         RenderTarget::kDefaultColorAttachmentConfig  //
 #ifndef FML_OS_ANDROID  // Reduce PSO variants for Vulkan.
         ,

impeller/entity/contents/content_context.h

@@ -17,6 +17,7 @@
 #include "impeller/entity/entity.h"
 #include "impeller/renderer/capabilities.h"
 #include "impeller/renderer/pipeline.h"
+#include "impeller/renderer/render_target.h"
 #include "impeller/scene/scene_context.h"
 
 #ifdef IMPELLER_DEBUG
@@ -333,6 +334,7 @@ struct ContentContextOptions {
 };
 
 class Tessellator;
+class RenderTargetCache;
 
 class ContentContext {
  public:
@@ -707,6 +709,10 @@ class ContentContext {
     return lazy_glyph_atlas_;
   }
 
+  std::shared_ptr<RenderTargetAllocator> GetRenderTargetCache() const {
+    return render_target_cache_;
+  }
+
  private:
   std::shared_ptr<Context> context_;
   std::shared_ptr<LazyGlyphAtlas> lazy_glyph_atlas_;
@@ -864,6 +870,7 @@ class ContentContext {
   bool is_valid_ = false;
   std::shared_ptr<Tessellator> tessellator_;
   std::shared_ptr<scene::SceneContext> scene_context_;
+  std::shared_ptr<RenderTargetAllocator> render_target_cache_;
   bool wireframe_ = false;
 
   FML_DISALLOW_COPY_AND_ASSIGN(ContentContext);

impeller/entity/contents/scene_contents.cc

@@ -45,9 +45,10 @@ bool SceneContents::Render(const ContentContext& renderer,
   }
 
   RenderTarget subpass_target = RenderTarget::CreateOffscreenMSAA(
-      *renderer.GetContext(),        // context
-      ISize(coverage.value().size),  // size
-      "SceneContents",               // label
+      *renderer.GetContext(),                  // context
+      *renderer.GetRenderTargetCache().get(),  // allocator
+      ISize(coverage.value().size),            // size
+      "SceneContents",                         // label
       RenderTarget::AttachmentConfigMSAA{
           .storage_mode = StorageMode::kDeviceTransient,
           .resolve_storage_mode = StorageMode::kDevicePrivate,

impeller/entity/entity_pass.cc

@@ -209,9 +209,10 @@ static EntityPassTarget CreateRenderTarget(ContentContext& renderer,
   RenderTarget target;
   if (context->GetCapabilities()->SupportsOffscreenMSAA()) {
     target = RenderTarget::CreateOffscreenMSAA(
-        *context,      // context
-        size,          // size
-        "EntityPass",  // label
+        *context,                                // context
+        *renderer.GetRenderTargetCache().get(),  // allocator
+        size,                                    // size
+        "EntityPass",                            // label
         RenderTarget::AttachmentConfigMSAA{
             .storage_mode = StorageMode::kDeviceTransient,
             .resolve_storage_mode = StorageMode::kDevicePrivate,
@@ -222,9 +223,10 @@ static EntityPassTarget CreateRenderTarget(ContentContext& renderer,
     );
   } else {
     target = RenderTarget::CreateOffscreen(
-        *context,      // context
-        size,          // size
-        "EntityPass",  // label
+        *context,                                // context
+        *renderer.GetRenderTargetCache().get(),  // allocator
+        size,                                    // size
+        "EntityPass",                            // label
         RenderTarget::AttachmentConfig{
             .storage_mode = StorageMode::kDevicePrivate,
             .load_action = LoadAction::kDontCare,
@@ -248,6 +250,7 @@ uint32_t EntityPass::GetTotalPassReads(ContentContext& renderer) const {
 
 bool EntityPass::Render(ContentContext& renderer,
                         const RenderTarget& render_target) const {
+  renderer.GetRenderTargetCache()->Start();
   auto root_render_target = render_target;
 
   if (root_render_target.GetColorAttachments().find(0u) ==
@@ -256,8 +259,10 @@ bool EntityPass::Render(ContentContext& renderer,
     return false;
   }
 
-  fml::ScopedCleanupClosure reset_lazy_glyph_atlas(
-      [&renderer]() { renderer.GetLazyGlyphAtlas()->ResetTextFrames(); });
+  fml::ScopedCleanupClosure reset_state([&renderer]() {
+    renderer.GetLazyGlyphAtlas()->ResetTextFrames();
+    renderer.GetRenderTargetCache()->End();
+  });
 
   IterateAllEntities([lazy_glyph_atlas =
                           renderer.GetLazyGlyphAtlas()](const Entity& entity) {
@@ -381,7 +386,8 @@ bool EntityPass::Render(ContentContext& renderer,
   // provided by the caller.
   else {
     root_render_target.SetupStencilAttachment(
-        *renderer.GetContext(), color0.texture->GetSize(),
+        *renderer.GetContext(), *renderer.GetRenderTargetCache().get(),
+        color0.texture->GetSize(),
         renderer.GetContext()->GetCapabilities()->SupportsOffscreenMSAA(),
         "ImpellerOnscreen",
         GetDefaultStencilConfig(reads_from_onscreen_backdrop));