Refactor AndroidContextGL, AndroidSurface and AndroidSurfaceGL (flutter/engine#18670)

engine/src/flutter/ci/licenses_golden/licenses_flutter

@@ -645,6 +645,8 @@ FILE: ../../../flutter/shell/gpu/gpu_surface_vulkan.h
 FILE: ../../../flutter/shell/gpu/gpu_surface_vulkan_delegate.cc
 FILE: ../../../flutter/shell/gpu/gpu_surface_vulkan_delegate.h
 FILE: ../../../flutter/shell/platform/android/AndroidManifest.xml
+FILE: ../../../flutter/shell/platform/android/android_context.cc
+FILE: ../../../flutter/shell/platform/android/android_context.h
 FILE: ../../../flutter/shell/platform/android/android_context_gl.cc
 FILE: ../../../flutter/shell/platform/android/android_context_gl.h
 FILE: ../../../flutter/shell/platform/android/android_environment_gl.cc

engine/src/flutter/shell/platform/android/BUILD.gn

@@ -23,6 +23,8 @@ shared_library("flutter_shell_native") {
 
   sources = [
     "$root_build_dir/flutter_icu/icudtl.o",
+    "android_context.cc",
+    "android_context.h",
     "android_context_gl.cc",
     "android_context_gl.h",
     "android_environment_gl.cc",

engine/src/flutter/shell/platform/android/android_context.cc

@@ -0,0 +1,37 @@
+// 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 "flutter/shell/platform/android/android_context.h"
+
+#include "flutter/shell/platform/android/android_context_gl.h"
+#include "flutter/shell/platform/android/android_environment_gl.h"
+
+namespace flutter {
+
+std::shared_ptr<AndroidContext> CreateContextGL() {
+  auto context_gl = std::make_shared<AndroidContextGL>(
+      AndroidRenderingAPI::kOpenGLES,
+      fml::MakeRefCounted<AndroidEnvironmentGL>());
+  FML_CHECK(context_gl->IsValid()) << "Could not create an Android context GL.";
+  return context_gl;
+}
+
+AndroidContext::AndroidContext(AndroidRenderingAPI rendering_api)
+    : rendering_api_(rendering_api) {}
+
+AndroidContext::~AndroidContext() = default;
+
+AndroidRenderingAPI AndroidContext::RenderingApi() const {
+  return rendering_api_;
+}
+
+std::shared_ptr<AndroidContext> AndroidContext::Create(
+    AndroidRenderingAPI rendering_api) {
+  if (rendering_api == AndroidRenderingAPI::kOpenGLES) {
+    return CreateContextGL();
+  }
+  return std::make_shared<AndroidContext>(rendering_api);
+}
+
+}  // namespace flutter

engine/src/flutter/shell/platform/android/android_context.h

@@ -0,0 +1,43 @@
+// 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.
+
+#ifndef FLUTTER_SHELL_PLATFORM_ANDROID_ANDROID_CONTEXT_H_
+#define FLUTTER_SHELL_PLATFORM_ANDROID_ANDROID_CONTEXT_H_
+
+#include "flutter/fml/macros.h"
+#include "flutter/fml/memory/ref_counted.h"
+#include "flutter/fml/memory/ref_ptr.h"
+#include "flutter/shell/common/platform_view.h"
+
+namespace flutter {
+
+enum class AndroidRenderingAPI {
+  kSoftware,
+  kOpenGLES,
+  kVulkan,
+};
+
+//------------------------------------------------------------------------------
+/// @brief      Holds state that is shared across Android surfaces.
+///
+class AndroidContext {
+ public:
+  AndroidContext(AndroidRenderingAPI rendering_api);
+
+  ~AndroidContext();
+
+  static std::shared_ptr<AndroidContext> Create(
+      AndroidRenderingAPI rendering_api);
+
+  AndroidRenderingAPI RenderingApi() const;
+
+ private:
+  const AndroidRenderingAPI rendering_api_;
+
+  FML_DISALLOW_COPY_AND_ASSIGN(AndroidContext);
+};
+
+}  // namespace flutter
+
+#endif  // FLUTTER_SHELL_PLATFORM_ANDROID_ANDROID_CONTEXT_H_

engine/src/flutter/shell/platform/android/android_context_gl.cc

@@ -105,62 +105,21 @@ static bool TeardownContext(EGLDisplay display, EGLContext context) {
   return true;
 }
 
-static bool TeardownSurface(EGLDisplay display, EGLSurface surface) {
-  if (surface != EGL_NO_SURFACE) {
-    return eglDestroySurface(display, surface) == EGL_TRUE;
-  }
-
-  return true;
-}
-
-// For onscreen rendering.
-bool AndroidContextGL::CreateWindowSurface(
-    fml::RefPtr<AndroidNativeWindow> window) {
-  // The configurations are only required when dealing with extensions or VG.
-  // We do neither.
-
-  window_ = std::move(window);
-  EGLDisplay display = environment_->Display();
-
-  const EGLint attribs[] = {EGL_NONE};
-
-  surface_ = eglCreateWindowSurface(
-      display, config_,
-      reinterpret_cast<EGLNativeWindowType>(window_->handle()), attribs);
-  return surface_ != EGL_NO_SURFACE;
-}
-
-// For offscreen rendering.
-bool AndroidContextGL::CreatePBufferSurface() {
-  // We only ever create pbuffer surfaces for background resource loading
-  // contexts. We never bind the pbuffer to anything.
-
-  EGLDisplay display = environment_->Display();
-
-  const EGLint attribs[] = {EGL_WIDTH, 1, EGL_HEIGHT, 1, EGL_NONE};
-
-  surface_ = eglCreatePbufferSurface(display, config_, attribs);
-  return surface_ != EGL_NO_SURFACE;
-}
-
-AndroidContextGL::AndroidContextGL(fml::RefPtr<AndroidEnvironmentGL> env,
-                                   const AndroidContextGL* share_context)
-    : environment_(env),
-      window_(nullptr),
-      config_(nullptr),
-      surface_(EGL_NO_SURFACE),
-      context_(EGL_NO_CONTEXT),
-      valid_(false) {
+AndroidContextGL::AndroidContextGL(
+    AndroidRenderingAPI rendering_api,
+    fml::RefPtr<AndroidEnvironmentGL> environment)
+    : AndroidContext(AndroidRenderingAPI::kOpenGLES),
+      environment_(environment),
+      config_(nullptr) {
   if (!environment_->IsValid()) {
+    FML_LOG(ERROR) << "Could not create an Android GL environment.";
     return;
   }
 
   bool success = false;
 
   // Choose a valid configuration.
-
   std::tie(success, config_) = ChooseEGLConfiguration(environment_->Display());
-
   if (!success) {
     FML_LOG(ERROR) << "Could not choose an EGL configuration.";
     LogLastEGLError();
@@ -168,19 +127,18 @@ AndroidContextGL::AndroidContextGL(fml::RefPtr<AndroidEnvironmentGL> env,
   }
 
   // Create a context for the configuration.
-
-  std::tie(success, context_) = CreateContext(
-      environment_->Display(), config_,
-      share_context != nullptr ? share_context->context_ : EGL_NO_CONTEXT);
-
+  std::tie(success, context_) =
+      CreateContext(environment_->Display(), config_, EGL_NO_CONTEXT);
   if (!success) {
     FML_LOG(ERROR) << "Could not create an EGL context";
     LogLastEGLError();
     return;
   }
 
-  if (!this->CreatePBufferSurface()) {
-    FML_LOG(ERROR) << "Could not create the EGL surface.";
+  std::tie(success, resource_context_) =
+      CreateContext(environment_->Display(), config_, context_);
+  if (!success) {
+    FML_LOG(ERROR) << "Could not create an EGL resource context";
     LogLastEGLError();
     return;
   }
@@ -196,13 +154,34 @@ AndroidContextGL::~AndroidContextGL() {
     LogLastEGLError();
   }
 
-  if (!TeardownSurface(environment_->Display(), surface_)) {
-    FML_LOG(ERROR)
-        << "Could not tear down the EGL surface. Possible resource leak.";
+  if (!TeardownContext(environment_->Display(), resource_context_)) {
+    FML_LOG(ERROR) << "Could not tear down the EGL resource context. Possible "
+                      "resource leak.";
     LogLastEGLError();
   }
 }
 
+EGLSurface AndroidContextGL::CreateOnscreenSurface(
+    fml::RefPtr<AndroidNativeWindow> window) const {
+  EGLDisplay display = environment_->Display();
+
+  const EGLint attribs[] = {EGL_NONE};
+
+  return eglCreateWindowSurface(
+      display, config_, reinterpret_cast<EGLNativeWindowType>(window->handle()),
+      attribs);
+}
+
+EGLSurface AndroidContextGL::CreateOffscreenSurface() const {
+  // We only ever create pbuffer surfaces for background resource loading
+  // contexts. We never bind the pbuffer to anything.
+  EGLDisplay display = environment_->Display();
+
+  const EGLint attribs[] = {EGL_WIDTH, 1, EGL_HEIGHT, 1, EGL_NONE};
+
+  return eglCreatePbufferSurface(display, config_, attribs);
+}
+
 fml::RefPtr<AndroidEnvironmentGL> AndroidContextGL::Environment() const {
   return environment_;
 }
@@ -211,8 +190,8 @@ bool AndroidContextGL::IsValid() const {
   return valid_;
 }
 
-bool AndroidContextGL::MakeCurrent() {
-  if (eglMakeCurrent(environment_->Display(), surface_, surface_, context_) !=
+bool AndroidContextGL::MakeCurrent(EGLSurface& surface) {
+  if (eglMakeCurrent(environment_->Display(), surface, surface, context_) !=
       EGL_TRUE) {
     FML_LOG(ERROR) << "Could not make the context current";
     LogLastEGLError();
@@ -221,6 +200,16 @@ bool AndroidContextGL::MakeCurrent() {
   return true;
 }
 
+bool AndroidContextGL::ResourceMakeCurrent(EGLSurface& surface) {
+  if (eglMakeCurrent(environment_->Display(), surface, surface,
+                     resource_context_) != EGL_TRUE) {
+    FML_LOG(ERROR) << "Could not make the context current";
+    LogLastEGLError();
+    return false;
+  }
+  return true;
+}
+
 bool AndroidContextGL::ClearCurrent() {
   if (eglGetCurrentContext() != context_) {
     return true;
@@ -234,18 +223,17 @@ bool AndroidContextGL::ClearCurrent() {
   return true;
 }
 
-bool AndroidContextGL::SwapBuffers() {
+bool AndroidContextGL::SwapBuffers(EGLSurface& surface) {
   TRACE_EVENT0("flutter", "AndroidContextGL::SwapBuffers");
-  return eglSwapBuffers(environment_->Display(), surface_);
+  return eglSwapBuffers(environment_->Display(), surface);
 }
 
-SkISize AndroidContextGL::GetSize() {
+SkISize AndroidContextGL::GetSize(EGLSurface& surface) {
   EGLint width = 0;
   EGLint height = 0;
 
-  if (!eglQuerySurface(environment_->Display(), surface_, EGL_WIDTH, &width) ||
-      !eglQuerySurface(environment_->Display(), surface_, EGL_HEIGHT,
-                       &height)) {
+  if (!eglQuerySurface(environment_->Display(), surface, EGL_WIDTH, &width) ||
+      !eglQuerySurface(environment_->Display(), surface, EGL_HEIGHT, &height)) {
     FML_LOG(ERROR) << "Unable to query EGL surface size";
     LogLastEGLError();
     return SkISize::Make(0, 0);
@@ -253,22 +241,11 @@ SkISize AndroidContextGL::GetSize() {
   return SkISize::Make(width, height);
 }
 
-bool AndroidContextGL::Resize(const SkISize& size) {
-  if (size == GetSize()) {
-    return true;
+bool AndroidContextGL::TeardownSurface(EGLSurface& surface) {
+  if (surface != EGL_NO_SURFACE) {
+    return eglDestroySurface(environment_->Display(), surface) == EGL_TRUE;
   }
 
-  ClearCurrent();
-
-  TeardownSurface(environment_->Display(), surface_);
-
-  if (!this->CreateWindowSurface(window_)) {
-    FML_LOG(ERROR) << "Unable to create EGL window surface on resize.";
-    return false;
-  }
-
-  MakeCurrent();
-
   return true;
 }
 

engine/src/flutter/shell/platform/android/android_context_gl.h

@@ -9,47 +9,111 @@
 #include "flutter/fml/memory/ref_counted.h"
 #include "flutter/fml/memory/ref_ptr.h"
 #include "flutter/shell/common/platform_view.h"
+#include "flutter/shell/platform/android/android_context.h"
 #include "flutter/shell/platform/android/android_environment_gl.h"
 #include "flutter/shell/platform/android/android_native_window.h"
 #include "third_party/skia/include/core/SkSize.h"
 
 namespace flutter {
 
-class AndroidContextGL : public fml::RefCountedThreadSafe<AndroidContextGL> {
+//------------------------------------------------------------------------------
+/// The Android context is used by `AndroidSurfaceGL` to create and manage
+/// EGL surfaces.
+///
+/// This context binds `EGLContext` to the current rendering thread and to the
+/// draw and read `EGLSurface`s.
+///
+class AndroidContextGL : public AndroidContext {
  public:
-  bool CreateWindowSurface(fml::RefPtr<AndroidNativeWindow> window);
-
-  bool CreatePBufferSurface();
-
-  fml::RefPtr<AndroidEnvironmentGL> Environment() const;
-
-  bool IsValid() const;
-
-  bool MakeCurrent();
-
-  bool ClearCurrent();
-
-  bool SwapBuffers();
-
-  SkISize GetSize();
-
-  bool Resize(const SkISize& size);
-
- private:
-  fml::RefPtr<AndroidEnvironmentGL> environment_;
-  fml::RefPtr<AndroidNativeWindow> window_;
-  EGLConfig config_;
-  EGLSurface surface_;
-  EGLContext context_;
-  bool valid_;
-
-  AndroidContextGL(fml::RefPtr<AndroidEnvironmentGL> env,
-                   const AndroidContextGL* share_context = nullptr);
+  AndroidContextGL(AndroidRenderingAPI rendering_api,
+                   fml::RefPtr<AndroidEnvironmentGL> environment);
 
   ~AndroidContextGL();
 
-  FML_FRIEND_MAKE_REF_COUNTED(AndroidContextGL);
-  FML_FRIEND_REF_COUNTED_THREAD_SAFE(AndroidContextGL);
+  //----------------------------------------------------------------------------
+  /// @brief      Allocates an new EGL window surface that is used for on-screen
+  ///             pixels.
+  ///
+  /// @attention  Consumers must tear down the surface by calling
+  ///             `AndroidContextGL::TeardownSurface`.
+  ///
+  /// @return     The window surface.
+  ///
+  EGLSurface CreateOnscreenSurface(
+      fml::RefPtr<AndroidNativeWindow> window) const;
+
+  //----------------------------------------------------------------------------
+  /// @brief      Allocates an 1x1 pbuffer surface that is used for making the
+  ///             offscreen current for texture uploads.
+  ///
+  /// @attention  Consumers must tear down the surface by calling
+  ///             `AndroidContextGL::TeardownSurface`.
+  ///
+  /// @return     The pbuffer surface.
+  ///
+  EGLSurface CreateOffscreenSurface() const;
+
+  //----------------------------------------------------------------------------
+  /// @return     The Android environment that contains a reference to the
+  /// display.
+  ///
+  fml::RefPtr<AndroidEnvironmentGL> Environment() const;
+
+  //----------------------------------------------------------------------------
+  /// @return     Whether the current context is valid. That is, if the EGL
+  /// contexts
+  ///             were successfully created.
+  ///
+  bool IsValid() const;
+
+  //----------------------------------------------------------------------------
+  /// @return     Whether the current context was successfully clear.
+  ///
+  bool ClearCurrent();
+
+  //----------------------------------------------------------------------------
+  /// @brief      Binds the EGLContext context to the current rendering thread
+  ///             and to the draw and read surface.
+  ///
+  /// @return     Whether the surface was made current.
+  ///
+  bool MakeCurrent(EGLSurface& surface);
+
+  //----------------------------------------------------------------------------
+  /// @brief      Binds the resource EGLContext context to the current rendering
+  ///             thread and to the draw and read surface.
+  ///
+  /// @return     Whether the surface was made current.
+  ///
+  bool ResourceMakeCurrent(EGLSurface& surface);
+
+  //----------------------------------------------------------------------------
+  /// @brief      This only applies to on-screen surfaces such as those created
+  ///             by `AndroidContextGL::CreateOnscreenSurface`.
+  ///
+  /// @return     Whether the EGL surface color buffer was swapped.
+  ///
+  bool SwapBuffers(EGLSurface& surface);
+
+  //----------------------------------------------------------------------------
+  /// @return     The size of an `EGLSurface`.
+  ///
+  SkISize GetSize(EGLSurface& surface);
+
+  //----------------------------------------------------------------------------
+  /// @brief      Destroys an `EGLSurface`.
+  ///
+  /// @return     Whether the surface was destroyed.
+  ///
+  bool TeardownSurface(EGLSurface& surface);
+
+ private:
+  fml::RefPtr<AndroidEnvironmentGL> environment_;
+  EGLConfig config_;
+  EGLContext context_;
+  EGLContext resource_context_;
+  bool valid_ = false;
+
   FML_DISALLOW_COPY_AND_ASSIGN(AndroidContextGL);
 };
 

engine/src/flutter/shell/platform/android/android_surface.cc

@@ -15,19 +15,24 @@
 namespace flutter {
 
 std::unique_ptr<AndroidSurface> AndroidSurface::Create(
-    bool use_software_rendering) {
-  if (use_software_rendering) {
-    auto software_surface = std::make_unique<AndroidSurfaceSoftware>();
-    return software_surface->IsValid() ? std::move(software_surface) : nullptr;
-  }
+    std::shared_ptr<AndroidContext> android_context) {
+  std::unique_ptr<AndroidSurface> surface;
+  switch (android_context->RenderingApi()) {
+    case AndroidRenderingAPI::kSoftware:
+      surface = std::make_unique<AndroidSurfaceSoftware>();
+      break;
+    case AndroidRenderingAPI::kOpenGLES:
+      surface = std::make_unique<AndroidSurfaceGL>(android_context);
+      break;
+    case AndroidRenderingAPI::kVulkan:
 #if SHELL_ENABLE_VULKAN
-  auto vulkan_surface = std::make_unique<AndroidSurfaceVulkan>();
-  return vulkan_surface->IsValid() ? std::move(vulkan_surface) : nullptr;
-#else   // SHELL_ENABLE_VULKAN
-  auto gl_surface = std::make_unique<AndroidSurfaceGL>();
-  return gl_surface->IsOffscreenContextValid() ? std::move(gl_surface)
-                                               : nullptr;
+      surface = std::make_unique<AndroidSurfaceVulkan>();
 #endif  // SHELL_ENABLE_VULKAN
+      break;
+  }
+  FML_CHECK(surface);
+  return surface->IsValid() ? std::move(surface) : nullptr;
+  ;
 }
 
 AndroidSurface::~AndroidSurface() = default;

engine/src/flutter/shell/platform/android/android_surface.h

@@ -12,6 +12,7 @@
 #include "flutter/fml/platform/android/jni_weak_ref.h"
 #include "flutter/shell/common/platform_view.h"
 #include "flutter/shell/common/surface.h"
+#include "flutter/shell/platform/android/android_context.h"
 #include "flutter/shell/platform/android/android_native_window.h"
 #include "third_party/skia/include/core/SkSize.h"
 
@@ -19,7 +20,8 @@ namespace flutter {
 
 class AndroidSurface {
  public:
-  static std::unique_ptr<AndroidSurface> Create(bool use_software_rendering);
+  static std::unique_ptr<AndroidSurface> Create(
+      std::shared_ptr<AndroidContext> android_context);
 
   virtual ~AndroidSurface();
 
@@ -27,9 +29,10 @@ class AndroidSurface {
 
   virtual void TeardownOnScreenContext() = 0;
 
-  virtual std::unique_ptr<Surface> CreateGPUSurface() = 0;
+  virtual std::unique_ptr<Surface> CreateGPUSurface(
+      GrContext* gr_context = nullptr) = 0;
 
-  virtual bool OnScreenSurfaceResize(const SkISize& size) const = 0;
+  virtual bool OnScreenSurfaceResize(const SkISize& size) = 0;
 
   virtual bool ResourceContextMakeCurrent() = 0;
 

engine/src/flutter/shell/platform/android/android_surface_gl.cc

@@ -11,120 +11,113 @@
 
 namespace flutter {
 
-static fml::RefPtr<AndroidContextGL> CreateResourceLoadingContext() {
-  auto environment = fml::MakeRefCounted<AndroidEnvironmentGL>();
-  if (!environment->IsValid()) {
-    return nullptr;
+AndroidSurfaceGL::AndroidSurfaceGL(
+    std::shared_ptr<AndroidContext> android_context)
+    : native_window_(nullptr),
+      onscreen_surface_(nullptr),
+      offscreen_surface_(nullptr) {
+  android_context_ =
+      std::static_pointer_cast<AndroidContextGL>(android_context);
+  // Acquire the offscreen surface.
+  offscreen_surface_ = android_context_->CreateOffscreenSurface();
+  if (offscreen_surface_ == EGL_NO_SURFACE) {
+    offscreen_surface_ = nullptr;
   }
-
-  auto context = fml::MakeRefCounted<AndroidContextGL>(environment);
-  if (!context->IsValid()) {
-    return nullptr;
-  }
-
-  return context;
-}
-
-AndroidSurfaceGL::AndroidSurfaceGL() {
-  // Acquire the offscreen context.
-  offscreen_context_ = CreateResourceLoadingContext();
-
-  if (!offscreen_context_ || !offscreen_context_->IsValid()) {
-    offscreen_context_ = nullptr;
-  }
-
   external_view_embedder_ = std::make_unique<AndroidExternalViewEmbedder>();
 }
 
-AndroidSurfaceGL::~AndroidSurfaceGL() = default;
-
-bool AndroidSurfaceGL::IsOffscreenContextValid() const {
-  return offscreen_context_ && offscreen_context_->IsValid();
+AndroidSurfaceGL::~AndroidSurfaceGL() {
+  if (offscreen_surface_) {
+    android_context_->TeardownSurface(offscreen_surface_);
+    offscreen_surface_ = nullptr;
+  }
+  if (onscreen_surface_) {
+    android_context_->TeardownSurface(onscreen_surface_);
+    onscreen_surface_ = nullptr;
+  }
 }
 
 void AndroidSurfaceGL::TeardownOnScreenContext() {
-  if (onscreen_context_) {
-    onscreen_context_->ClearCurrent();
-  }
-  onscreen_context_ = nullptr;
+  android_context_->ClearCurrent();
 }
 
 bool AndroidSurfaceGL::IsValid() const {
-  if (!onscreen_context_ || !offscreen_context_) {
-    return false;
+  return offscreen_surface_ && android_context_->IsValid();
+}
+
+std::unique_ptr<Surface> AndroidSurfaceGL::CreateGPUSurface(
+    GrContext* gr_context) {
+  if (gr_context) {
+    return std::make_unique<GPUSurfaceGL>(sk_ref_sp(gr_context), this, true);
+  }
+  return std::make_unique<GPUSurfaceGL>(this, true);
+}
+
+bool AndroidSurfaceGL::OnScreenSurfaceResize(const SkISize& size) {
+  FML_DCHECK(IsValid());
+  FML_DCHECK(onscreen_surface_);
+  FML_DCHECK(native_window_);
+
+  if (size == android_context_->GetSize(onscreen_surface_)) {
+    return true;
   }
 
-  return onscreen_context_->IsValid() && offscreen_context_->IsValid();
-}
+  android_context_->ClearCurrent();
+  android_context_->TeardownSurface(onscreen_surface_);
 
-std::unique_ptr<Surface> AndroidSurfaceGL::CreateGPUSurface() {
-  auto surface = std::make_unique<GPUSurfaceGL>(this, true);
-  return surface->IsValid() ? std::move(surface) : nullptr;
-}
-
-bool AndroidSurfaceGL::OnScreenSurfaceResize(const SkISize& size) const {
-  FML_DCHECK(onscreen_context_ && onscreen_context_->IsValid());
-  return onscreen_context_->Resize(size);
+  onscreen_surface_ = android_context_->CreateOnscreenSurface(native_window_);
+  if (!onscreen_surface_ || onscreen_surface_ == EGL_NO_SURFACE) {
+    FML_LOG(ERROR) << "Unable to create EGL window surface on resize.";
+    return false;
+  }
+  android_context_->MakeCurrent(onscreen_surface_);
+  return true;
 }
 
 bool AndroidSurfaceGL::ResourceContextMakeCurrent() {
-  FML_DCHECK(offscreen_context_ && offscreen_context_->IsValid());
-  return offscreen_context_->MakeCurrent();
+  FML_DCHECK(IsValid());
+  return android_context_->ResourceMakeCurrent(offscreen_surface_);
 }
 
 bool AndroidSurfaceGL::ResourceContextClearCurrent() {
-  FML_DCHECK(offscreen_context_ && offscreen_context_->IsValid());
-  return offscreen_context_->ClearCurrent();
+  FML_DCHECK(IsValid());
+  return android_context_->ClearCurrent();
 }
 
 bool AndroidSurfaceGL::SetNativeWindow(
     fml::RefPtr<AndroidNativeWindow> window) {
-  // In any case, we want to get rid of our current onscreen context.
-  onscreen_context_ = nullptr;
-
-  // If the offscreen context has not been setup, we dont have the sharegroup.
-  // So bail.
-  if (!offscreen_context_ || !offscreen_context_->IsValid()) {
+  FML_DCHECK(IsValid());
+  FML_DCHECK(window);
+  native_window_ = window;
+  // Create the onscreen surface.
+  onscreen_surface_ = android_context_->CreateOnscreenSurface(window);
+  if (onscreen_surface_ == EGL_NO_SURFACE) {
     return false;
   }
-
-  // Create the onscreen context.
-  onscreen_context_ = fml::MakeRefCounted<AndroidContextGL>(
-      offscreen_context_->Environment(),
-      offscreen_context_.get() /* sharegroup */);
-
-  if (!onscreen_context_->IsValid()) {
-    onscreen_context_ = nullptr;
-    return false;
-  }
-
-  if (!onscreen_context_->CreateWindowSurface(std::move(window))) {
-    onscreen_context_ = nullptr;
-    return false;
-  }
-
   return true;
 }
 
 std::unique_ptr<GLContextResult> AndroidSurfaceGL::GLContextMakeCurrent() {
-  FML_DCHECK(onscreen_context_ && onscreen_context_->IsValid());
+  FML_DCHECK(IsValid());
+  FML_DCHECK(onscreen_surface_);
   auto default_context_result = std::make_unique<GLContextDefaultResult>(
-      onscreen_context_->MakeCurrent());
+      android_context_->MakeCurrent(onscreen_surface_));
   return std::move(default_context_result);
 }
 
 bool AndroidSurfaceGL::GLContextClearCurrent() {
-  FML_DCHECK(onscreen_context_ && onscreen_context_->IsValid());
-  return onscreen_context_->ClearCurrent();
+  FML_DCHECK(IsValid());
+  return android_context_->ClearCurrent();
 }
 
 bool AndroidSurfaceGL::GLContextPresent() {
-  FML_DCHECK(onscreen_context_ && onscreen_context_->IsValid());
-  return onscreen_context_->SwapBuffers();
+  FML_DCHECK(IsValid());
+  FML_DCHECK(onscreen_surface_);
+  return android_context_->SwapBuffers(onscreen_surface_);
 }
 
 intptr_t AndroidSurfaceGL::GLContextFBO() const {
-  FML_DCHECK(onscreen_context_ && onscreen_context_->IsValid());
+  FML_DCHECK(IsValid());
   // The default window bound framebuffer on Android.
   return 0;
 }

engine/src/flutter/shell/platform/android/android_surface_gl.h

@@ -20,23 +20,21 @@ namespace flutter {
 class AndroidSurfaceGL final : public GPUSurfaceGLDelegate,
                                public AndroidSurface {
  public:
-  AndroidSurfaceGL();
+  AndroidSurfaceGL(std::shared_ptr<AndroidContext> android_context);
 
   ~AndroidSurfaceGL() override;
 
-  bool IsOffscreenContextValid() const;
-
   // |AndroidSurface|
   bool IsValid() const override;
 
   // |AndroidSurface|
-  std::unique_ptr<Surface> CreateGPUSurface() override;
+  std::unique_ptr<Surface> CreateGPUSurface(GrContext* gr_context) override;
 
   // |AndroidSurface|
   void TeardownOnScreenContext() override;
 
   // |AndroidSurface|
-  bool OnScreenSurfaceResize(const SkISize& size) const override;
+  bool OnScreenSurfaceResize(const SkISize& size) override;
 
   // |AndroidSurface|
   bool ResourceContextMakeCurrent() override;
@@ -63,9 +61,11 @@ class AndroidSurfaceGL final : public GPUSurfaceGLDelegate,
   ExternalViewEmbedder* GetExternalViewEmbedder() override;
 
  private:
-  fml::RefPtr<AndroidContextGL> onscreen_context_;
-  fml::RefPtr<AndroidContextGL> offscreen_context_;
+  fml::RefPtr<AndroidNativeWindow> native_window_;
   std::unique_ptr<AndroidExternalViewEmbedder> external_view_embedder_;
+  std::shared_ptr<AndroidContextGL> android_context_;
+  EGLSurface onscreen_surface_;
+  EGLSurface offscreen_surface_;
 
   FML_DISALLOW_COPY_AND_ASSIGN(AndroidSurfaceGL);
 };

engine/src/flutter/shell/platform/android/android_surface_software.cc

@@ -57,7 +57,8 @@ bool AndroidSurfaceSoftware::ResourceContextClearCurrent() {
   return false;
 }
 
-std::unique_ptr<Surface> AndroidSurfaceSoftware::CreateGPUSurface() {
+std::unique_ptr<Surface> AndroidSurfaceSoftware::CreateGPUSurface(
+    GrContext* gr_context) {
   if (!IsValid()) {
     return nullptr;
   }
@@ -143,7 +144,7 @@ ExternalViewEmbedder* AndroidSurfaceSoftware::GetExternalViewEmbedder() {
 
 void AndroidSurfaceSoftware::TeardownOnScreenContext() {}
 
-bool AndroidSurfaceSoftware::OnScreenSurfaceResize(const SkISize& size) const {
+bool AndroidSurfaceSoftware::OnScreenSurfaceResize(const SkISize& size) {
   return true;
 }
 

engine/src/flutter/shell/platform/android/android_surface_software.h

@@ -31,13 +31,13 @@ class AndroidSurfaceSoftware final : public AndroidSurface,
   bool ResourceContextClearCurrent() override;
 
   // |AndroidSurface|
-  std::unique_ptr<Surface> CreateGPUSurface() override;
+  std::unique_ptr<Surface> CreateGPUSurface(GrContext* gr_context) override;
 
   // |AndroidSurface|
   void TeardownOnScreenContext() override;
 
   // |AndroidSurface|
-  bool OnScreenSurfaceResize(const SkISize& size) const override;
+  bool OnScreenSurfaceResize(const SkISize& size) override;
 
   // |AndroidSurface|
   bool SetNativeWindow(fml::RefPtr<AndroidNativeWindow> window) override;

engine/src/flutter/shell/platform/android/android_surface_vulkan.cc

@@ -27,7 +27,8 @@ void AndroidSurfaceVulkan::TeardownOnScreenContext() {
   // Nothing to do.
 }
 
-std::unique_ptr<Surface> AndroidSurfaceVulkan::CreateGPUSurface() {
+std::unique_ptr<Surface> AndroidSurfaceVulkan::CreateGPUSurface(
+    GrContext* gr_context) {
   if (!IsValid()) {
     return nullptr;
   }
@@ -54,7 +55,7 @@ std::unique_ptr<Surface> AndroidSurfaceVulkan::CreateGPUSurface() {
   return gpu_surface;
 }
 
-bool AndroidSurfaceVulkan::OnScreenSurfaceResize(const SkISize& size) const {
+bool AndroidSurfaceVulkan::OnScreenSurfaceResize(const SkISize& size) {
   return true;
 }
 

engine/src/flutter/shell/platform/android/android_surface_vulkan.h

@@ -27,13 +27,13 @@ class AndroidSurfaceVulkan : public AndroidSurface,
   bool IsValid() const override;
 
   // |AndroidSurface|
-  std::unique_ptr<Surface> CreateGPUSurface() override;
+  std::unique_ptr<Surface> CreateGPUSurface(GrContext* gr_context) override;
 
   // |AndroidSurface|
   void TeardownOnScreenContext() override;
 
   // |AndroidSurface|
-  bool OnScreenSurfaceResize(const SkISize& size) const override;
+  bool OnScreenSurfaceResize(const SkISize& size) override;
 
   // |AndroidSurface|
   bool ResourceContextMakeCurrent() override;

engine/src/flutter/shell/platform/android/platform_view_android.cc

@@ -10,6 +10,7 @@
 #include "flutter/fml/synchronization/waitable_event.h"
 #include "flutter/shell/common/shell_io_manager.h"
 #include "flutter/shell/gpu/gpu_surface_gl_delegate.h"
+#include "flutter/shell/platform/android/android_context.h"
 #include "flutter/shell/platform/android/android_external_texture_gl.h"
 #include "flutter/shell/platform/android/android_surface_gl.h"
 #include "flutter/shell/platform/android/platform_message_response_android.h"
@@ -24,8 +25,18 @@ PlatformViewAndroid::PlatformViewAndroid(
     fml::jni::JavaObjectWeakGlobalRef java_object,
     bool use_software_rendering)
     : PlatformView(delegate, std::move(task_runners)),
-      java_object_(java_object),
-      android_surface_(AndroidSurface::Create(use_software_rendering)) {
+      java_object_(java_object) {
+  std::shared_ptr<AndroidContext> android_context;
+  if (use_software_rendering) {
+    android_context = AndroidContext::Create(AndroidRenderingAPI::kSoftware);
+  } else {
+#if SHELL_ENABLE_VULKAN
+    android_context = AndroidContext::Create(AndroidRenderingAPI::kVulkan);
+#else   // SHELL_ENABLE_VULKAN
+    android_context = AndroidContext::Create(AndroidRenderingAPI::kOpenGLES);
+#endif  // SHELL_ENABLE_VULKAN
+  }
+  android_surface_ = AndroidSurface::Create(android_context);
   FML_CHECK(android_surface_)
       << "Could not create an OpenGL, Vulkan or Software surface to setup "
          "rendering.";

engine/src/flutter/shell/platform/android/platform_view_android.h

@@ -75,7 +75,8 @@ class PlatformViewAndroid final : public PlatformView {
 
  private:
   const fml::jni::JavaObjectWeakGlobalRef java_object_;
-  const std::unique_ptr<AndroidSurface> android_surface_;
+
+  std::unique_ptr<AndroidSurface> android_surface_;
   // We use id 0 to mean that no response is expected.
   int next_response_id_ = 1;
   std::unordered_map<int, fml::RefPtr<flutter::PlatformMessageResponse>>