Linux texture support

ci/licenses_golden/licenses_flutter

@@ -1270,6 +1270,9 @@ FILE: ../../../flutter/shell/platform/linux/fl_dart_project.cc
 FILE: ../../../flutter/shell/platform/linux/fl_dart_project_test.cc
 FILE: ../../../flutter/shell/platform/linux/fl_engine.cc
 FILE: ../../../flutter/shell/platform/linux/fl_engine_private.h
+FILE: ../../../flutter/shell/platform/linux/fl_external_texture_gl.cc
+FILE: ../../../flutter/shell/platform/linux/fl_external_texture_gl.h
+FILE: ../../../flutter/shell/platform/linux/fl_external_texture_gl_test.cc
 FILE: ../../../flutter/shell/platform/linux/fl_json_message_codec.cc
 FILE: ../../../flutter/shell/platform/linux/fl_json_message_codec_test.cc
 FILE: ../../../flutter/shell/platform/linux/fl_json_method_codec.cc
@@ -1310,6 +1313,9 @@ FILE: ../../../flutter/shell/platform/linux/fl_string_codec.cc
 FILE: ../../../flutter/shell/platform/linux/fl_string_codec_test.cc
 FILE: ../../../flutter/shell/platform/linux/fl_text_input_plugin.cc
 FILE: ../../../flutter/shell/platform/linux/fl_text_input_plugin.h
+FILE: ../../../flutter/shell/platform/linux/fl_texture_registrar.cc
+FILE: ../../../flutter/shell/platform/linux/fl_texture_registrar_private.h
+FILE: ../../../flutter/shell/platform/linux/fl_texture_registrar_test.cc
 FILE: ../../../flutter/shell/platform/linux/fl_value.cc
 FILE: ../../../flutter/shell/platform/linux/fl_value_test.cc
 FILE: ../../../flutter/shell/platform/linux/fl_view.cc
@@ -1330,6 +1336,7 @@ FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_plugin_regis
 FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_standard_message_codec.h
 FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_standard_method_codec.h
 FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_string_codec.h
+FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_texture_registrar.h
 FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_value.h
 FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_view.h
 FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/flutter_linux.h

shell/platform/linux/BUILD.gn

@@ -59,6 +59,7 @@ _public_headers = [
   "public/flutter_linux/fl_standard_message_codec.h",
   "public/flutter_linux/fl_standard_method_codec.h",
   "public/flutter_linux/fl_string_codec.h",
+  "public/flutter_linux/fl_texture_registrar.h",
   "public/flutter_linux/fl_value.h",
   "public/flutter_linux/fl_view.h",
   "public/flutter_linux/flutter_linux.h",
@@ -80,6 +81,7 @@ source_set("flutter_linux_sources") {
     "fl_binary_messenger.cc",
     "fl_dart_project.cc",
     "fl_engine.cc",
+    "fl_external_texture_gl.cc",
     "fl_json_message_codec.cc",
     "fl_json_method_codec.cc",
     "fl_key_event_plugin.cc",
@@ -99,6 +101,7 @@ source_set("flutter_linux_sources") {
     "fl_standard_method_codec.cc",
     "fl_string_codec.cc",
     "fl_text_input_plugin.cc",
+    "fl_texture_registrar.cc",
     "fl_value.cc",
     "fl_view.cc",
   ]
@@ -138,6 +141,7 @@ executable("flutter_linux_unittests") {
     "fl_binary_codec_test.cc",
     "fl_binary_messenger_test.cc",
     "fl_dart_project_test.cc",
+    "fl_external_texture_gl_test.cc",
     "fl_json_message_codec_test.cc",
     "fl_json_method_codec_test.cc",
     "fl_message_codec_test.cc",
@@ -147,6 +151,7 @@ executable("flutter_linux_unittests") {
     "fl_standard_message_codec_test.cc",
     "fl_standard_method_codec_test.cc",
     "fl_string_codec_test.cc",
+    "fl_texture_registrar_test.cc",
     "fl_value_test.cc",
     "testing/fl_test.cc",
     "testing/mock_egl.cc",

shell/platform/linux/fl_binary_messenger_test.cc

@@ -6,21 +6,8 @@
 #include "gtest/gtest.h"
 
 #include "flutter/shell/platform/linux/fl_binary_messenger_private.h"
-#include "flutter/shell/platform/linux/fl_engine_private.h"
 #include "flutter/shell/platform/linux/public/flutter_linux/fl_binary_messenger.h"
-#include "flutter/shell/platform/linux/testing/mock_renderer.h"
-
-// Creates a mock engine that responds to platform messages.
-static FlEngine* make_mock_engine() {
-  g_autoptr(FlDartProject) project = fl_dart_project_new();
-  g_autoptr(FlMockRenderer) renderer = fl_mock_renderer_new();
-  g_autoptr(FlEngine) engine = fl_engine_new(project, FL_RENDERER(renderer));
-  g_autoptr(GError) engine_error = nullptr;
-  EXPECT_TRUE(fl_engine_start(engine, &engine_error));
-  EXPECT_EQ(engine_error, nullptr);
-
-  return static_cast<FlEngine*>(g_object_ref(engine));
-}
+#include "flutter/shell/platform/linux/testing/fl_test.h"
 
 // Checks sending nullptr for a message works.
 TEST(FlBinaryMessengerTest, SendNullptrMessage) {

shell/platform/linux/fl_engine.cc

@@ -5,10 +5,12 @@
 #include "flutter/shell/platform/linux/public/flutter_linux/fl_engine.h"
 #include "flutter/shell/platform/linux/fl_engine_private.h"
 
+#include "flutter/shell/platform/embedder/embedder.h"
 #include "flutter/shell/platform/linux/fl_binary_messenger_private.h"
 #include "flutter/shell/platform/linux/fl_plugin_registrar_private.h"
 #include "flutter/shell/platform/linux/fl_renderer.h"
 #include "flutter/shell/platform/linux/fl_renderer_headless.h"
+#include "flutter/shell/platform/linux/fl_texture_registrar_private.h"
 #include "flutter/shell/platform/linux/public/flutter_linux/fl_plugin_registry.h"
 
 #include <gmodule.h>
@@ -27,6 +29,7 @@ struct _FlEngine {
   FlDartProject* project;
   FlRenderer* renderer;
   FlBinaryMessenger* binary_messenger;
+  FlTextureRegistrar* texture_registrar;
   FlutterEngineAOTData aot_data;
   FLUTTER_API_SYMBOL(FlutterEngine) engine;
 
@@ -210,6 +213,21 @@ static bool fl_engine_gl_make_resource_current(void* user_data) {
   return result;
 }
 
+// Called by the engine to retrieve an external texture.
+static bool fl_engine_gl_external_texture_frame_callback(
+    void* user_data,
+    int64_t texture_id,
+    size_t width,
+    size_t height,
+    FlutterOpenGLTexture* texture) {
+  FlEngine* self = static_cast<FlEngine*>(user_data);
+  if (!self->texture_registrar) {
+    return false;
+  }
+  return fl_texture_registrar_populate_texture(
+      self->texture_registrar, texture_id, width, height, texture);
+}
+
 // Called by the engine to determine if it is on the GTK thread.
 static bool fl_engine_runs_task_on_current_thread(void* user_data) {
   FlEngine* self = static_cast<FlEngine*>(user_data);
@@ -268,7 +286,8 @@ static FlPluginRegistrar* fl_engine_get_registrar_for_plugin(
     const gchar* name) {
   FlEngine* self = FL_ENGINE(registry);
 
-  return fl_plugin_registrar_new(nullptr, self->binary_messenger);
+  return fl_plugin_registrar_new(nullptr, self->binary_messenger,
+                                 self->texture_registrar);
 }
 
 static void fl_engine_plugin_registry_iface_init(
@@ -291,6 +310,7 @@ static void fl_engine_dispose(GObject* object) {
 
   g_clear_object(&self->project);
   g_clear_object(&self->renderer);
+  g_clear_object(&self->texture_registrar);
   g_clear_object(&self->binary_messenger);
 
   if (self->platform_message_handler_destroy_notify) {
@@ -310,6 +330,7 @@ static void fl_engine_class_init(FlEngineClass* klass) {
 static void fl_engine_init(FlEngine* self) {
   self->thread = g_thread_self();
 
+  self->texture_registrar = fl_texture_registrar_new(self);
   self->binary_messenger = fl_binary_messenger_new(self);
 }
 
@@ -340,6 +361,8 @@ gboolean fl_engine_start(FlEngine* self, GError** error) {
   config.open_gl.fbo_callback = fl_engine_gl_get_fbo;
   config.open_gl.present = fl_engine_gl_present;
   config.open_gl.make_resource_current = fl_engine_gl_make_resource_current;
+  config.open_gl.gl_external_texture_frame_callback =
+      fl_engine_gl_external_texture_frame_callback;
 
   FlutterTaskRunnerDescription platform_task_runner = {};
   platform_task_runner.struct_size = sizeof(FlutterTaskRunnerDescription);
@@ -571,8 +594,33 @@ void fl_engine_send_mouse_pointer_event(FlEngine* self,
   FlutterEngineSendPointerEvent(self->engine, &fl_event, 1);
 }
 
+gboolean fl_engine_mark_texture_frame_available(FlEngine* self,
+                                                int64_t texture_id) {
+  g_return_val_if_fail(FL_IS_ENGINE(self), FALSE);
+  return FlutterEngineMarkExternalTextureFrameAvailable(self->engine,
+                                                        texture_id) == kSuccess;
+}
+
+gboolean fl_engine_register_external_texture(FlEngine* self,
+                                             int64_t texture_id) {
+  g_return_val_if_fail(FL_IS_ENGINE(self), FALSE);
+  return FlutterEngineRegisterExternalTexture(self->engine, texture_id) ==
+         kSuccess;
+}
+
+void fl_engine_unregister_external_texture(FlEngine* self, int64_t texture_id) {
+  g_return_if_fail(FL_IS_ENGINE(self));
+  FlutterEngineUnregisterExternalTexture(self->engine, texture_id);
+}
+
 G_MODULE_EXPORT FlBinaryMessenger* fl_engine_get_binary_messenger(
     FlEngine* self) {
   g_return_val_if_fail(FL_IS_ENGINE(self), nullptr);
   return self->binary_messenger;
 }
+
+G_MODULE_EXPORT FlTextureRegistrar* fl_engine_get_texture_registrar(
+    FlEngine* self) {
+  g_return_val_if_fail(FL_IS_ENGINE(self), nullptr);
+  return self->texture_registrar;
+}

shell/platform/linux/fl_engine_private.h

@@ -175,6 +175,42 @@ GBytes* fl_engine_send_platform_message_finish(FlEngine* engine,
                                                GAsyncResult* result,
                                                GError** error);
 
+/**
+ * fl_engine_mark_texture_frame_available:
+ * @engine: an #FlEngine.
+ * @texture_id: the identifier of the texture whose frame has been updated.
+ *
+ * Tells the Flutter engine that a new texture frame is available for the given
+ * texture.
+ *
+ * Returns: %TRUE on success.
+ */
+gboolean fl_engine_mark_texture_frame_available(FlEngine* engine,
+                                                int64_t texture_id);
+
+/**
+ * fl_engine_register_external_texture:
+ * @engine: an #FlEngine.
+ * @texture_id: the identifier of the texture that is available.
+ *
+ * Tells the Flutter engine that a new external texture is available.
+ *
+ * Returns: %TRUE on success.
+ */
+gboolean fl_engine_register_external_texture(FlEngine* engine,
+                                             int64_t texture_id);
+
+/**
+ * fl_engine_unregister_external_texture:
+ * @engine: an #FlEngine.
+ * @texture_id: the identifier of the texture that is not available anymore.
+ *
+ * Tells the Flutter engine that an existing external texture is not available
+ * anymore.
+ */
+void fl_engine_unregister_external_texture(FlEngine* engine,
+                                           int64_t texture_id);
+
 G_END_DECLS
 
 #endif  // FLUTTER_SHELL_PLATFORM_LINUX_FL_ENGINE_PRIVATE_H_

shell/platform/linux/fl_external_texture_gl.cc

@@ -0,0 +1,136 @@
+// 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/linux/fl_external_texture_gl.h"
+
+#include <EGL/egl.h>
+#include <GL/gl.h>
+#include <gmodule.h>
+
+typedef struct {
+  bool valid;
+  void (*genTextures)(GLsizei n, GLuint* textures);
+  void (*bindTexture)(GLenum target, GLuint texture);
+  void (*texParameteri)(GLenum target, GLenum pname, GLenum param);
+  void (*texImage2D)(GLenum target,
+                     GLint level,
+                     GLint internalformat,
+                     GLsizei width,
+                     GLsizei height,
+                     GLint border,
+                     GLenum format,
+                     GLenum type,
+                     const void* data);
+  void (*deleteTextures)(GLsizei n, const GLuint* textures);
+} glFuncs;
+
+static glFuncs* load_gl_funcs() {
+  static glFuncs funcs;
+  if (!funcs.valid) {
+    funcs.genTextures = reinterpret_cast<void (*)(GLsizei, GLuint*)>(
+        eglGetProcAddress("glGenTextures"));
+    funcs.bindTexture = reinterpret_cast<void (*)(GLenum, GLuint)>(
+        eglGetProcAddress("glBindTexture"));
+    funcs.texParameteri = reinterpret_cast<void (*)(GLenum, GLenum, GLenum)>(
+        eglGetProcAddress("glTexParameteri"));
+    funcs.texImage2D =
+        reinterpret_cast<void (*)(GLenum, GLint, GLint, GLsizei, GLsizei, GLint,
+                                  GLenum, GLenum, const void*)>(
+            eglGetProcAddress("glTexImage2D"));
+    funcs.deleteTextures = reinterpret_cast<void (*)(GLsizei, const GLuint*)>(
+        eglGetProcAddress("glDeleteTextures"));
+    funcs.valid = true;
+  }
+  return &funcs;
+}
+
+struct _FlExternalTextureGl {
+  GObject parent_instance;
+  GLuint gl_texture_id;
+  FlTextureCallback callback;
+  void* user_data;
+};
+
+G_DEFINE_TYPE(FlExternalTextureGl, fl_external_texture_gl, G_TYPE_OBJECT)
+
+static void fl_external_texture_gl_dispose(GObject* object) {
+  FlExternalTextureGl* self = FL_EXTERNAL_TEXTURE_GL(object);
+  glFuncs* gl = load_gl_funcs();
+  gl->deleteTextures(1, &self->gl_texture_id);
+
+  G_OBJECT_CLASS(fl_external_texture_gl_parent_class)->dispose(object);
+}
+
+static void fl_external_texture_gl_class_init(FlExternalTextureGlClass* klass) {
+  G_OBJECT_CLASS(klass)->dispose = fl_external_texture_gl_dispose;
+}
+
+static void fl_external_texture_gl_init(FlExternalTextureGl* self) {}
+
+int64_t fl_external_texture_gl_texture_id(FlExternalTextureGl* self) {
+  g_return_val_if_fail(FL_IS_EXTERNAL_TEXTURE_GL(self), -1);
+  return reinterpret_cast<int64_t>(self);
+}
+
+gboolean fl_external_texture_gl_populate_texture(
+    FlExternalTextureGl* self,
+    size_t width,
+    size_t height,
+    FlutterOpenGLTexture* opengl_texture) {
+  g_return_val_if_fail(FL_IS_EXTERNAL_TEXTURE_GL(self), FALSE);
+
+  size_t real_width = width, real_height = height;
+  if (!fl_external_texture_gl_copy_pixel_buffer(self, &real_width,
+                                                &real_height)) {
+    return false;
+  }
+
+  opengl_texture->target = GL_TEXTURE_2D;
+  opengl_texture->name = self->gl_texture_id;
+  opengl_texture->format = GL_RGBA8;
+  opengl_texture->destruction_callback = nullptr;
+  opengl_texture->user_data = nullptr;
+  opengl_texture->width = real_width;
+  opengl_texture->height = real_height;
+
+  return TRUE;
+}
+
+gboolean fl_external_texture_gl_copy_pixel_buffer(FlExternalTextureGl* self,
+                                                  size_t* width,
+                                                  size_t* height) {
+  g_return_val_if_fail(FL_IS_EXTERNAL_TEXTURE_GL(self), FALSE);
+
+  const uint8_t* buffer;
+  if (self->callback(width, height, &buffer, self->user_data) != TRUE) {
+    return FALSE;
+  }
+
+  glFuncs* gl = load_gl_funcs();
+  if (self->gl_texture_id == 0) {
+    gl->genTextures(1, &self->gl_texture_id);
+    gl->bindTexture(GL_TEXTURE_2D, self->gl_texture_id);
+    gl->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+    gl->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+    gl->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    gl->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+  } else {
+    gl->bindTexture(GL_TEXTURE_2D, self->gl_texture_id);
+  }
+  gl->texImage2D(GL_TEXTURE_2D, 0, GL_RGBA, *width, *height, 0, GL_RGBA,
+                 GL_UNSIGNED_BYTE, buffer);
+  return TRUE;
+}
+
+FlExternalTextureGl* fl_external_texture_gl_new(
+    FlTextureCallback texture_callback,
+    void* user_data) {
+  FlExternalTextureGl* self = FL_EXTERNAL_TEXTURE_GL(
+      g_object_new(fl_external_texture_gl_get_type(), nullptr));
+
+  self->callback = texture_callback;
+  self->user_data = user_data;
+
+  return self;
+}