Start on the entity model.

engine/src/flutter/impeller/compositor/BUILD.gn

@@ -10,6 +10,8 @@ impeller_component("compositor") {
     "allocator.mm",
     "buffer.h",
     "buffer.mm",
+    "command.h",
+    "command.mm",
     "comparable.cc",
     "comparable.h",
     "context.h",
@@ -30,6 +32,8 @@ impeller_component("compositor") {
     "render_pass.mm",
     "renderer.h",
     "renderer.mm",
+    "sampler.h",
+    "sampler.mm",
     "shader_function.h",
     "shader_function.mm",
     "shader_library.h",

engine/src/flutter/impeller/compositor/command.h

@@ -0,0 +1,32 @@
+// 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.
+
+#pragma once
+
+#include <map>
+#include <memory>
+
+#include "flutter/fml/macros.h"
+#include "impeller/compositor/buffer.h"
+#include "impeller/compositor/pipeline.h"
+
+namespace impeller {
+
+class Texture;
+class Sampler;
+
+struct Bindings {
+  std::map<size_t, BufferView> buffers;
+  std::map<size_t, std::shared_ptr<Texture>> textures;
+  std::map<size_t, std::shared_ptr<Texture>> samplers;
+};
+
+struct Command {
+  std::shared_ptr<Pipeline> pipeline;
+  Bindings vertex_bindings;
+  Bindings fragment_bindings;
+  BufferView index_buffer;
+};
+
+}  // namespace impeller

engine/src/flutter/impeller/compositor/command.mm

@@ -0,0 +1,7 @@
+// 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 "impeller/compositor/command.h"
+
+namespace impeller {}  // namespace impeller

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

@@ -15,9 +15,7 @@ namespace impeller {
 
 class Renderer {
  public:
-  Renderer(std::string shaders_directory);
-
-  ~Renderer();
+  virtual ~Renderer();
 
   bool IsValid() const;
 
@@ -27,6 +25,13 @@ class Renderer {
 
   std::shared_ptr<Context> GetContext() const;
 
+ protected:
+  Renderer(std::string shaders_directory);
+
+  virtual bool OnRender() = 0;
+
+  virtual bool OnSurfaceSizeDidChange(Size size) = 0;
+
  private:
   std::shared_ptr<Context> context_;
   std::unique_ptr<Surface> surface_;

engine/src/flutter/impeller/compositor/renderer.mm

@@ -38,7 +38,8 @@ bool Renderer::SurfaceSizeDidChange(Size size) {
   }
 
   size_ = size;
-  return true;
+
+  return OnSurfaceSizeDidChange(size_);
 }
 
 bool Renderer::Render() {

engine/src/flutter/impeller/compositor/sampler.h

@@ -0,0 +1,21 @@
+// 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.
+
+#pragma once
+
+#include "flutter/fml/macros.h"
+
+namespace impeller {
+
+class Sampler {
+ public:
+  Sampler();
+
+  ~Sampler();
+
+ private:
+  FML_DISALLOW_COPY_AND_ASSIGN(Sampler);
+};
+
+}  // namespace impeller

engine/src/flutter/impeller/compositor/sampler.mm

@@ -2,10 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "impeller/compositor/context.h"
+#include "impeller/compositor/sampler.h"
 
 namespace impeller {
 
-bool RenderBox(std::shared_ptr<Context> context);
+Sampler::Sampler() = default;
+
+Sampler::~Sampler() = default;
 
 }  // namespace impeller

engine/src/flutter/impeller/entity/BUILD.gn

@@ -8,7 +8,12 @@ impeller_component("entity") {
   sources = [
     "entity.cc",
     "entity.h",
+    "entity_renderer.h",
+    "entity_renderer.mm",
   ]
 
-  public_deps = [ "../image" ]
+  public_deps = [
+    "../compositor",
+    "../image",
+  ]
 }

engine/src/flutter/impeller/entity/entity.h

@@ -4,7 +4,7 @@
 
 #pragma once
 
-#include "impeller/entity/color.h"
+#include "impeller/geometry/color.h"
 #include "impeller/geometry/matrix.h"
 #include "impeller/geometry/path.h"
 #include "impeller/geometry/rect.h"

engine/src/flutter/impeller/entity/entity_renderer.h

@@ -0,0 +1,29 @@
+// 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.
+
+#pragma once
+
+#include "flutter/fml/macros.h"
+#include "impeller/compositor/renderer.h"
+#include "impeller/entity/entity.h"
+
+namespace impeller {
+
+class EntityRenderer final : public Renderer {
+ public:
+  EntityRenderer(std::string shaders_directory);
+
+  ~EntityRenderer() override;
+
+ private:
+  std::shared_ptr<Entity> root_;
+
+  bool OnRender() override;
+
+  bool OnSurfaceSizeDidChange(Size size) override;
+
+  FML_DISALLOW_COPY_AND_ASSIGN(EntityRenderer);
+};
+
+}  // namespace impeller

engine/src/flutter/impeller/entity/entity_renderer.mm

@@ -0,0 +1,23 @@
+// 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 "impeller/entity/entity_renderer.h"
+
+namespace impeller {
+
+EntityRenderer::EntityRenderer(std::string shaders_directory)
+    : Renderer(std::move(shaders_directory)),
+      root_(std::make_shared<Entity>()) {}
+
+EntityRenderer::~EntityRenderer() = default;
+
+bool EntityRenderer::OnRender() {
+  return false;
+}
+
+bool EntityRenderer::OnSurfaceSizeDidChange(Size size) {
+  return false;
+}
+
+}  // namespace impeller

engine/src/flutter/impeller/host/BUILD.gn

@@ -46,6 +46,7 @@ executable("host") {
   deps = [
     ":impeller_host_fixtures",
     ":impeller_host_shaders",
+    "../entity",
     "../primitives",
     "//flutter/fml",
   ]

engine/src/flutter/impeller/host/impeller_renderer.mm

@@ -4,17 +4,15 @@
 
 #import <ModelIO/ModelIO.h>
 #import <simd/simd.h>
-
-#import "assets_location.h"
-#include "flutter/fml/logging.h"
-#import "impeller/compositor/renderer.h"
-#import "impeller/primitives/box.h"
-#import "impeller_renderer.h"
-#import "shaders_location.h"
-// Include header shared between C code here, which executes Metal API commands,
-// and .metal files
 #import "ShaderTypes.h"
 
+#include "assets_location.h"
+#include "flutter/fml/logging.h"
+#include "impeller/entity/entity_renderer.h"
+#include "impeller/primitives/box_primitive.h"
+#include "impeller_renderer.h"
+#include "shaders_location.h"
+
 static const NSUInteger kMaxBuffersInFlight = 3;
 
 static const size_t kAlignedUniformsSize = (sizeof(Uniforms) & ~0xFF) + 0x100;
@@ -53,17 +51,13 @@ static const size_t kAlignedUniformsSize = (sizeof(Uniforms) & ~0xFF) + 0x100;
     [self _loadAssets];
   }
 
-  renderer_ = std::make_unique<impeller::Renderer>(
+  renderer_ = std::make_unique<impeller::EntityRenderer>(
       impeller::ImpellerShadersDirectory());
 
   if (!renderer_->IsValid()) {
     FML_LOG(ERROR) << "Impeller Renderer is not valid.";
   }
 
-  if (!impeller::RenderBox(renderer_->GetContext())) {
-    FML_LOG(ERROR) << "Could not render box.";
-  }
-
   return self;
 }
 
@@ -233,7 +227,9 @@ static const size_t kAlignedUniformsSize = (sizeof(Uniforms) & ~0xFF) + 0x100;
 }
 
 - (void)drawInMTKView:(nonnull MTKView*)view {
-  renderer_->Render();
+  if (!renderer_->Render()) {
+    FML_LOG(ERROR) << "Could not render.";
+  }
   /// Per frame updates here
   dispatch_semaphore_wait(_inFlightSemaphore, DISPATCH_TIME_FOREVER);
 

engine/src/flutter/impeller/image/BUILD.gn

@@ -12,5 +12,7 @@ impeller_component("image") {
     "image_result.h",
   ]
 
+  deps = [ "../third_party/stb" ]
+
   public_deps = [ "../geometry" ]
 }

engine/src/flutter/impeller/primitives/BUILD.gn

@@ -14,8 +14,10 @@ impeller_shaders("impeller_shaders") {
 
 impeller_component("primitives") {
   sources = [
-    "box.h",
-    "box.mm",
+    "box_primitive.h",
+    "box_primitive.mm",
+    "primitive.h",
+    "primitive.mm",
   ]
 
   public_deps = [ "../compositor" ]

engine/src/flutter/impeller/primitives/box_primitive.h

@@ -0,0 +1,26 @@
+// 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 "impeller/compositor/context.h"
+#include "impeller/primitives/primitive.h"
+
+namespace impeller {
+
+class BoxPrimitive final : public Primitive {
+ public:
+  BoxPrimitive(std::shared_ptr<Context> context);
+
+  ~BoxPrimitive() override;
+
+  virtual bool Encode(RenderPass& pass) const override;
+
+ private:
+  bool is_valid_ = false;
+
+  FML_DISALLOW_COPY_AND_ASSIGN(BoxPrimitive);
+};
+
+bool RenderBox(std::shared_ptr<Context> context);
+
+}  // namespace impeller

engine/src/flutter/impeller/primitives/box_primitive.mm

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "impeller/primitives/box.h"
+#include "impeller/primitives/box_primitive.h"
 
 #include <memory>
 
@@ -15,7 +15,8 @@
 
 namespace impeller {
 
-bool RenderBox(std::shared_ptr<Context> context) {
+BoxPrimitive::BoxPrimitive(std::shared_ptr<Context> context)
+    : Primitive(context) {
   PipelineDescriptor desc;
   desc.SetLabel(shader::BoxVertexInfo::kLabel);
 
@@ -34,7 +35,7 @@ bool RenderBox(std::shared_ptr<Context> context) {
     if (!vertex_descriptor->SetStageInputs(
             shader::BoxVertexInfo::kAllShaderStageInputs)) {
       FML_LOG(ERROR) << "Could not configure vertex descriptor.";
-      return false;
+      return;
     }
     desc.SetVertexDescriptor(std::move(vertex_descriptor));
   }
@@ -43,10 +44,16 @@ bool RenderBox(std::shared_ptr<Context> context) {
       context->GetPipelineLibrary()->GetRenderPipeline(std::move(desc)).get();
   if (!pipeline) {
     FML_LOG(ERROR) << "Could not create the render pipeline.";
-    return false;
+    return;
   }
 
-  return true;
+  is_valid_ = true;
+}
+
+BoxPrimitive::~BoxPrimitive() = default;
+
+bool BoxPrimitive::Encode(RenderPass& pass) const {
+  return false;
 }
 
 }  // namespace impeller

engine/src/flutter/impeller/primitives/primitive.h

@@ -0,0 +1,31 @@
+// 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.
+
+#pragma once
+
+#include <memory>
+
+#include "flutter/fml/macros.h"
+#include "impeller/compositor/context.h"
+#include "impeller/compositor/render_pass.h"
+
+namespace impeller {
+
+class Primitive {
+ public:
+  Primitive(std::shared_ptr<Context>);
+
+  virtual ~Primitive();
+
+  std::shared_ptr<Context> GetContext() const;
+
+  virtual bool Encode(RenderPass& pass) const = 0;
+
+ private:
+  std::shared_ptr<Context> context_;
+
+  FML_DISALLOW_COPY_AND_ASSIGN(Primitive);
+};
+
+}  // namespace impeller

engine/src/flutter/impeller/primitives/primitive.mm

@@ -0,0 +1,18 @@
+// 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 "impeller/primitives/primitive.h"
+
+namespace impeller {
+
+Primitive::Primitive(std::shared_ptr<Context> context)
+    : context_(std::move(context)) {}
+
+Primitive::~Primitive() = default;
+
+std::shared_ptr<Context> Primitive::GetContext() const {
+  return context_;
+}
+
+}  // namespace impeller