[macOS] Merge FlutterRenderer and implementation

Previously FlutterRenderer was a protocol with two implementing classes:
FlutterOpenGLRenderer and FlutterMetalRenderer. Now that we've
eliminated the macOS OpenGL backend, this abstraction no longer makes
sense. This replaces the existing FlutterRenderer protocol with a
concrete implementation class, consisting of the Metal implementation.

Issue: flutter/flutter#108304
Issue: flutter/flutter#114445

Author: cbracken

ci/licenses_golden/licenses_flutter

@@ -2643,9 +2643,6 @@ FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMenuP
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMenuPlugin.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMenuPluginTest.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMenuPlugin_Internal.h
-FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.h
-FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.mm
-FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalRendererTest.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalSurfaceManagerTest.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMouseCursorPlugin.h
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMouseCursorPlugin.mm
@@ -2656,6 +2653,8 @@ FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterPlatf
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterPlatformViewController.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterPlatformViewControllerTest.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h
+FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderer.mm
+FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterRendererTest.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterResizableBackingStoreProvider.h
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterResizableBackingStoreProvider.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterResizeSynchronizer.h

shell/platform/darwin/macos/BUILD.gn

@@ -82,15 +82,14 @@ source_set("flutter_framework_source") {
     "framework/Source/FlutterMenuPlugin.h",
     "framework/Source/FlutterMenuPlugin.mm",
     "framework/Source/FlutterMenuPlugin_Internal.h",
-    "framework/Source/FlutterMetalRenderer.h",
-    "framework/Source/FlutterMetalRenderer.mm",
     "framework/Source/FlutterMouseCursorPlugin.h",
     "framework/Source/FlutterMouseCursorPlugin.mm",
     "framework/Source/FlutterPlatformNodeDelegateMac.h",
     "framework/Source/FlutterPlatformNodeDelegateMac.mm",
     "framework/Source/FlutterPlatformViewController.h",
     "framework/Source/FlutterPlatformViewController.mm",
     "framework/Source/FlutterRenderer.h",
+    "framework/Source/FlutterRenderer.mm",
     "framework/Source/FlutterResizableBackingStoreProvider.h",
     "framework/Source/FlutterResizableBackingStoreProvider.mm",
     "framework/Source/FlutterResizeSynchronizer.h",
@@ -177,10 +176,10 @@ executable("flutter_desktop_darwin_unittests") {
     "framework/Source/FlutterEngineTestUtils.mm",
     "framework/Source/FlutterKeyboardManagerUnittests.mm",
     "framework/Source/FlutterMenuPluginTest.mm",
-    "framework/Source/FlutterMetalRendererTest.mm",
     "framework/Source/FlutterMetalSurfaceManagerTest.mm",
     "framework/Source/FlutterPlatformNodeDelegateMacTest.mm",
     "framework/Source/FlutterPlatformViewControllerTest.mm",
+    "framework/Source/FlutterRendererTest.mm",
     "framework/Source/FlutterTextInputPluginTest.mm",
     "framework/Source/FlutterTextInputSemanticsObjectTest.mm",
     "framework/Source/FlutterViewControllerTest.mm",

shell/platform/darwin/macos/framework/Source/FlutterEngine.mm

@@ -12,9 +12,9 @@
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterCompositor.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterDartProject_Internal.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterMenuPlugin.h"
-#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterMouseCursorPlugin.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterPlatformViewController.h"
+#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterViewController_Internal.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProvider.h"
 #include "flutter/shell/platform/embedder/embedder.h"
@@ -246,7 +246,7 @@ - (instancetype)initWithName:(NSString*)labelPrefix
   _embedderAPI.struct_size = sizeof(FlutterEngineProcTable);
   FlutterEngineGetProcAddresses(&_embedderAPI);
 
-  _renderer = [[FlutterMetalRenderer alloc] initWithFlutterEngine:self];
+  _renderer = [[FlutterRenderer alloc] initWithFlutterEngine:self];
 
   NSNotificationCenter* notificationCenter = [NSNotificationCenter defaultCenter];
   [notificationCenter addObserver:self
@@ -422,9 +422,8 @@ - (FlutterCompositor*)createFlutterCompositor {
 
   __weak FlutterEngine* weakSelf = self;
 
-  FlutterMetalRenderer* metalRenderer = reinterpret_cast<FlutterMetalRenderer*>(_renderer);
   _macOSCompositor = std::make_unique<flutter::FlutterCompositor>(
-      _viewProvider, _platformViewController, metalRenderer.device);
+      _viewProvider, _platformViewController, _renderer.device);
   _macOSCompositor->SetPresentCallback([weakSelf](bool has_flutter_content) {
     if (has_flutter_content) {
       return [weakSelf.renderer present] == YES;

shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h

@@ -24,7 +24,7 @@
  * Provides the renderer config needed to initialize the engine and also handles external
  * texture management.
  */
-@property(nonatomic, readonly, nullable) id<FlutterRenderer> renderer;
+@property(nonatomic, readonly, nullable) FlutterRenderer* renderer;
 
 /**
  * Function pointers for interacting with the embedder.h API.

shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.h

@@ -12,7 +12,18 @@
 /**
  * Rendering backend agnostic FlutterRendererConfig provider to be used by the embedder API.
  */
-@protocol FlutterRenderer <FlutterTextureRegistry, FlutterTextureRegistrarDelegate>
+@interface FlutterRenderer
+    : FlutterTextureRegistrar <FlutterTextureRegistry, FlutterTextureRegistrarDelegate>
+
+/**
+ * Interface to the system GPU. Used to issue all the rendering commands.
+ */
+@property(nonatomic, readonly, nonnull) id<MTLDevice> device;
+
+/**
+ * Used to get the command buffers for the MTLDevice to render to.
+ */
+@property(nonatomic, readonly, nonnull) id<MTLCommandQueue> commandQueue;
 
 /**
  * Intializes the renderer with the given FlutterEngine.
@@ -39,4 +50,15 @@
  */
 - (void)presentWithoutContent;
 
+/**
+ * Creates a Metal texture for the given size.
+ */
+- (FlutterMetalTexture)createTextureForSize:(CGSize)size;
+
+/**
+ * Populates the texture registry with the provided metalTexture.
+ */
+- (BOOL)populateTextureWithIdentifier:(int64_t)textureID
+                         metalTexture:(nonnull FlutterMetalExternalTexture*)metalTexture;
+
 @end

shell/platform/darwin/macos/framework/Source/FlutterRenderer.h

@@ -1,9 +1,8 @@
-
 // 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.
 
-#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.h"
+#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h"
 
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterExternalTextureMetal.h"
@@ -15,8 +14,7 @@
 static FlutterMetalTexture OnGetNextDrawable(FlutterEngine* engine,
                                              const FlutterFrameInfo* frameInfo) {
   CGSize size = CGSizeMake(frameInfo->size.width, frameInfo->size.height);
-  FlutterMetalRenderer* metalRenderer = reinterpret_cast<FlutterMetalRenderer*>(engine.renderer);
-  return [metalRenderer createTextureForSize:size];
+  return [engine.renderer createTextureForSize:size];
 }
 
 static bool OnPresentDrawable(FlutterEngine* engine, const FlutterMetalTexture* texture) {
@@ -28,13 +26,13 @@ static bool OnAcquireExternalTexture(FlutterEngine* engine,
                                      size_t width,
                                      size_t height,
                                      FlutterMetalExternalTexture* metalTexture) {
-  FlutterMetalRenderer* metalRenderer = reinterpret_cast<FlutterMetalRenderer*>(engine.renderer);
-  return [metalRenderer populateTextureWithIdentifier:textureIdentifier metalTexture:metalTexture];
+  return [engine.renderer populateTextureWithIdentifier:textureIdentifier
+                                           metalTexture:metalTexture];
 }
 
-#pragma mark - FlutterMetalRenderer implementation
+#pragma mark - FlutterRenderer implementation
 
-@implementation FlutterMetalRenderer {
+@implementation FlutterRenderer {
   FlutterView* _flutterView;
 
   FlutterDarwinContextMetalSkia* _darwinMetalContext;

shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.mm renamed to shell/platform/darwin/macos/framework/Source/FlutterRenderer.mm

@@ -7,7 +7,7 @@
 #import "flutter/shell/platform/darwin/macos/framework/Headers/FlutterEngine.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterDartProject_Internal.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h"
-#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.h"
+#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterView.h"
 #include "flutter/shell/platform/embedder/embedder.h"
 #include "flutter/shell/platform/embedder/test_utils/proc_table_replacement.h"
@@ -26,18 +26,18 @@
 }
 }  // namespace
 
-TEST(FlutterMetalRenderer, PresentDelegatesToFlutterView) {
+TEST(FlutterRenderer, PresentDelegatesToFlutterView) {
   FlutterEngine* engine = CreateTestEngine();
-  FlutterMetalRenderer* renderer = [[FlutterMetalRenderer alloc] initWithFlutterEngine:engine];
+  FlutterRenderer* renderer = [[FlutterRenderer alloc] initWithFlutterEngine:engine];
   id mockFlutterView = OCMClassMock([FlutterView class]);
   [(FlutterView*)[mockFlutterView expect] present];
   [renderer setFlutterView:mockFlutterView];
   [renderer present];
 }
 
-TEST(FlutterMetalRenderer, TextureReturnedByFlutterView) {
+TEST(FlutterRenderer, TextureReturnedByFlutterView) {
   FlutterEngine* engine = CreateTestEngine();
-  FlutterMetalRenderer* renderer = [[FlutterMetalRenderer alloc] initWithFlutterEngine:engine];
+  FlutterRenderer* renderer = [[FlutterRenderer alloc] initWithFlutterEngine:engine];
   id mockFlutterView = OCMClassMock([FlutterView class]);
   FlutterFrameInfo frameInfo;
   frameInfo.struct_size = sizeof(FlutterFrameInfo);

shell/platform/darwin/macos/framework/Source/FlutterMetalRendererTest.mm renamed to shell/platform/darwin/macos/framework/Source/FlutterRendererTest.mm

@@ -14,7 +14,7 @@
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterKeyPrimaryResponder.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterKeyboardManager.h"
-#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.h"
+#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterTextInputSemanticsObject.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterView.h"
 #import "flutter/shell/platform/embedder/embedder.h"
@@ -364,9 +364,8 @@ - (BOOL)isDispatchingKeyEvent:(NSEvent*)event {
 
 - (void)loadView {
   FlutterView* flutterView;
-  FlutterMetalRenderer* metalRenderer = reinterpret_cast<FlutterMetalRenderer*>(_engine.renderer);
-  id<MTLDevice> device = metalRenderer.device;
-  id<MTLCommandQueue> commandQueue = metalRenderer.commandQueue;
+  id<MTLDevice> device = _engine.renderer.device;
+  id<MTLCommandQueue> commandQueue = _engine.renderer.commandQueue;
   if (!device || !commandQueue) {
     NSLog(@"Unable to create FlutterView; no MTLDevice or MTLCommandQueue available.");
     return;

shell/platform/darwin/macos/framework/Source/FlutterViewController.mm

@@ -11,7 +11,7 @@
 #import "flutter/shell/platform/darwin/macos/framework/Headers/FlutterEngine.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterDartProject_Internal.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h"
-#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterMetalRenderer.h"
+#import "flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterViewControllerTestUtils.h"
 #import "flutter/testing/testing.h"
 
@@ -269,7 +269,7 @@ - (bool)testKeyEventsArePropagatedIfNotHandled {
 - (bool)testFlutterViewIsConfigured {
   id engineMock = OCMClassMock([FlutterEngine class]);
 
-  id renderer_ = [[FlutterMetalRenderer alloc] initWithFlutterEngine:engineMock];
+  FlutterRenderer* renderer_ = [[FlutterRenderer alloc] initWithFlutterEngine:engineMock];
   OCMStub([engineMock renderer]).andReturn(renderer_);
 
   FlutterViewController* viewController = [[FlutterViewController alloc] initWithEngine:engineMock
@@ -460,7 +460,7 @@ + (void)respondFalseForSendEvent:(const FlutterKeyEvent&)event
 - (bool)testTrackpadGesturesAreSentToFramework {
   id engineMock = OCMClassMock([FlutterEngine class]);
   // Need to return a real renderer to allow view controller to load.
-  id renderer_ = [[FlutterMetalRenderer alloc] initWithFlutterEngine:engineMock];
+  FlutterRenderer* renderer_ = [[FlutterRenderer alloc] initWithFlutterEngine:engineMock];
   OCMStub([engineMock renderer]).andReturn(renderer_);
   __block bool called = false;
   __block FlutterPointerEvent last_event;