shell/platform/linux/fl_engine.cc - external/github.com/flutter/engine - Git at Google

 // 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/public/flutter_linux/fl_engine.h"
 #include "flutter/shell/platform/linux/fl_engine_private.h"

 #include "flutter/shell/platform/linux/fl_binary_messenger_private.h"
 #include "flutter/shell/platform/linux/fl_renderer.h"

 #include <gmodule.h>

 static constexpr int kMicrosecondsPerNanosecond = 1000;

 // Unique number associated with platform tasks
 static constexpr size_t kPlatformTaskRunnerIdentifier = 1;

 struct _FlEngine {
   GObject parent_instance;

   // Thread the GLib main loop is running on
   GThread* thread;

   FlDartProject* project;
   FlRenderer* renderer;
   FlBinaryMessenger* binary_messenger;
   FLUTTER_API_SYMBOL(FlutterEngine) engine;

   // Function to call when a platform message is received
   FlEnginePlatformMessageHandler platform_message_handler;
   gpointer platform_message_handler_data;
 };

 G_DEFINE_QUARK(fl_engine_error_quark, fl_engine_error)

 G_DEFINE_TYPE(FlEngine, fl_engine, G_TYPE_OBJECT)

 // Subclass of GSource that integrates Flutter tasks into the GLib main loop
 typedef struct {
   GSource parent;
   FlEngine* self;
   FlutterTask task;
 } FlutterSource;

 // Callback to run a Flutter task in the GLib main loop
 static gboolean flutter_source_dispatch(GSource* source,
                                         GSourceFunc callback,
                                         gpointer user_data) {
   FlutterSource* fl_source = reinterpret_cast<FlutterSource*>(source);
   FlEngine* self = fl_source->self;

   FlutterEngineResult result =
       FlutterEngineRunTask(self->engine, &fl_source->task);
   if (result != kSuccess)
     g_warning("Failed to run Flutter task\n");

   return G_SOURCE_REMOVE;
 }

 // Table of functions for Flutter GLib main loop integration
 static GSourceFuncs flutter_source_funcs = {
     nullptr,                  // prepare
     nullptr,                  // check
     flutter_source_dispatch,  // dispatch
     nullptr,                  // finalize
     nullptr,
     nullptr  // Internal usage
 };

 // Flutter engine callbacks

 static void* fl_engine_gl_proc_resolver(void* user_data, const char* name) {
   FlEngine* self = static_cast<FlEngine*>(user_data);
   return fl_renderer_get_proc_address(self->renderer, name);
 }

 static bool fl_engine_gl_make_current(void* user_data) {
   FlEngine* self = static_cast<FlEngine*>(user_data);
   g_autoptr(GError) error = nullptr;
   gboolean result = fl_renderer_make_current(self->renderer, &error);
   if (!result)
     g_warning("%s", error->message);
   return result;
 }

 static bool fl_engine_gl_clear_current(void* user_data) {
   FlEngine* self = static_cast<FlEngine*>(user_data);
   g_autoptr(GError) error = nullptr;
   gboolean result = fl_renderer_clear_current(self->renderer, &error);
   if (!result)
     g_warning("%s", error->message);
   return result;
 }

 static uint32_t fl_engine_gl_get_fbo(void* user_data) {
   FlEngine* self = static_cast<FlEngine*>(user_data);
   return fl_renderer_get_fbo(self->renderer);
 }

 static bool fl_engine_gl_present(void* user_data) {
   FlEngine* self = static_cast<FlEngine*>(user_data);
   g_autoptr(GError) error = nullptr;
   gboolean result = fl_renderer_present(self->renderer, &error);
   if (!result)
     g_warning("%s", error->message);
   return result;
 }

 static bool fl_engine_runs_task_on_current_thread(void* user_data) {
   FlEngine* self = static_cast<FlEngine*>(user_data);
   return self->thread == g_thread_self();
 }

 static void fl_engine_post_task(FlutterTask task,
                                 uint64_t target_time_nanos,
                                 void* user_data) {
   FlEngine* self = static_cast<FlEngine*>(user_data);

   g_autoptr(GSource) source =
       g_source_new(&flutter_source_funcs, sizeof(FlutterSource));
   FlutterSource* fl_source = reinterpret_cast<FlutterSource*>(source);
   fl_source->self = self;
   fl_source->task = task;
   g_source_set_ready_time(source,
                           target_time_nanos / kMicrosecondsPerNanosecond);
   g_source_attach(source, nullptr);
 }

 static void fl_engine_platform_message_cb(const FlutterPlatformMessage* message,
                                           void* user_data) {
   FlEngine* self = FL_ENGINE(user_data);

   gboolean handled = FALSE;
   if (self->platform_message_handler != nullptr) {
     g_autoptr(GBytes) data =
         g_bytes_new(message->message, message->message_size);
     handled = self->platform_message_handler(
         self, message->channel, data, message->response_handle,
         self->platform_message_handler_data);
   }

   if (!handled)
     fl_engine_send_platform_message_response(self, message->response_handle,
                                              nullptr, nullptr);
 }

 static void fl_engine_platform_message_response_cb(const uint8_t* data,
                                                    size_t data_length,
                                                    void* user_data) {
   g_autoptr(GTask) task = G_TASK(user_data);
   g_task_return_pointer(task, g_bytes_new(data, data_length),
                         (GDestroyNotify)g_bytes_unref);
 }

 static void fl_engine_dispose(GObject* object) {
   FlEngine* self = FL_ENGINE(object);

   FlutterEngineShutdown(self->engine);

   g_clear_object(&self->project);
   g_clear_object(&self->renderer);
   g_clear_object(&self->binary_messenger);

   G_OBJECT_CLASS(fl_engine_parent_class)->dispose(object);
 }

 static void fl_engine_class_init(FlEngineClass* klass) {
   G_OBJECT_CLASS(klass)->dispose = fl_engine_dispose;
 }

 static void fl_engine_init(FlEngine* self) {
   self->thread = g_thread_self();

   self->binary_messenger = fl_binary_messenger_new(self);
 }

 FlEngine* fl_engine_new(FlDartProject* project, FlRenderer* renderer) {
   g_return_val_if_fail(FL_IS_DART_PROJECT(project), nullptr);
   g_return_val_if_fail(FL_IS_RENDERER(renderer), nullptr);

   FlEngine* self =
       static_cast<FlEngine*>(g_object_new(fl_engine_get_type(), nullptr));
   self->project = static_cast<FlDartProject*>(g_object_ref(project));
   self->renderer = static_cast<FlRenderer*>(g_object_ref(renderer));
   return self;
 }

 gboolean fl_engine_start(FlEngine* self, GError** error) {
   g_return_val_if_fail(FL_IS_ENGINE(self), FALSE);

   if (!fl_renderer_start(self->renderer, error))
     return FALSE;

   FlutterRendererConfig config = {};
   config.type = kOpenGL;
   config.open_gl.struct_size = sizeof(FlutterOpenGLRendererConfig);
   config.open_gl.gl_proc_resolver = fl_engine_gl_proc_resolver;
   config.open_gl.make_current = fl_engine_gl_make_current;
   config.open_gl.clear_current = fl_engine_gl_clear_current;
   config.open_gl.fbo_callback = fl_engine_gl_get_fbo;
   config.open_gl.present = fl_engine_gl_present;

   FlutterTaskRunnerDescription platform_task_runner = {};
   platform_task_runner.struct_size = sizeof(FlutterTaskRunnerDescription);
   platform_task_runner.user_data = self;
   platform_task_runner.runs_task_on_current_thread_callback =
       fl_engine_runs_task_on_current_thread;
   platform_task_runner.post_task_callback = fl_engine_post_task;
   platform_task_runner.identifier = kPlatformTaskRunnerIdentifier;

   FlutterCustomTaskRunners custom_task_runners = {};
   custom_task_runners.struct_size = sizeof(FlutterCustomTaskRunners);
   custom_task_runners.platform_task_runner = &platform_task_runner;

   FlutterProjectArgs args = {};
   args.struct_size = sizeof(FlutterProjectArgs);
   args.assets_path = fl_dart_project_get_assets_path(self->project);
   args.icu_data_path = fl_dart_project_get_icu_data_path(self->project);
   args.platform_message_callback = fl_engine_platform_message_cb;
   args.custom_task_runners = &custom_task_runners;

   FlutterEngineResult result = FlutterEngineInitialize(
       FLUTTER_ENGINE_VERSION, &config, &args, self, &self->engine);
   if (result != kSuccess) {
     g_set_error(error, fl_engine_error_quark(), FL_ENGINE_ERROR_FAILED,
                 "Failed to initialize Flutter engine");
     return FALSE;
   }

   result = FlutterEngineRunInitialized(self->engine);
   if (result != kSuccess) {
     g_set_error(error, fl_engine_error_quark(), FL_ENGINE_ERROR_FAILED,
                 "Failed to run Flutter engine");
     return FALSE;
   }

   return TRUE;
 }

 void fl_engine_set_platform_message_handler(
     FlEngine* self,
     FlEnginePlatformMessageHandler handler,
     gpointer user_data) {
   g_return_if_fail(FL_IS_ENGINE(self));
   g_return_if_fail(handler != nullptr);

   self->platform_message_handler = handler;
   self->platform_message_handler_data = user_data;
 }

 gboolean fl_engine_send_platform_message_response(
     FlEngine* self,
     const FlutterPlatformMessageResponseHandle* handle,
     GBytes* response,
     GError** error) {
   g_return_val_if_fail(FL_IS_ENGINE(self), FALSE);
   g_return_val_if_fail(handle != nullptr, FALSE);

   gsize data_length = 0;
   const uint8_t* data = nullptr;
   if (response != nullptr)
     data =
         static_cast<const uint8_t*>(g_bytes_get_data(response, &data_length));
   FlutterEngineResult result = FlutterEngineSendPlatformMessageResponse(
       self->engine, handle, data, data_length);

   if (result != kSuccess) {
     g_set_error(error, fl_renderer_error_quark(), FL_RENDERER_ERROR_FAILED,
                 "Failed to send platorm message response");
     return FALSE;
   }

   return TRUE;
 }

 void fl_engine_send_platform_message(FlEngine* self,
                                      const gchar* channel,
                                      GBytes* message,
                                      GCancellable* cancellable,
                                      GAsyncReadyCallback callback,
                                      gpointer user_data) {
   g_return_if_fail(FL_IS_ENGINE(self));

   GTask* task = nullptr;
   FlutterPlatformMessageResponseHandle* response_handle = nullptr;
   if (callback != nullptr) {
     task = g_task_new(self, cancellable, callback, user_data);

     FlutterEngineResult result = FlutterPlatformMessageCreateResponseHandle(
         self->engine, fl_engine_platform_message_response_cb, task,
         &response_handle);
     if (result != kSuccess) {
       g_task_return_new_error(task, fl_engine_error_quark(),
                               FL_ENGINE_ERROR_FAILED,
                               "Failed to create response handle");
       g_object_unref(task);
       return;
     }
   }

   FlutterPlatformMessage fl_message = {};
   fl_message.struct_size = sizeof(fl_message);
   fl_message.channel = channel;
   fl_message.message =
       message != nullptr
           ? static_cast<const uint8_t*>(g_bytes_get_data(message, nullptr))
           : nullptr;
   fl_message.message_size = message != nullptr ? g_bytes_get_size(message) : 0;
   fl_message.response_handle = response_handle;
   FlutterEngineResult result =
       FlutterEngineSendPlatformMessage(self->engine, &fl_message);

   if (result != kSuccess && task != nullptr) {
     g_task_return_new_error(task, fl_engine_error_quark(),
                             FL_ENGINE_ERROR_FAILED,
                             "Failed to send platform messages");
     g_object_unref(task);
   }

   if (response_handle != nullptr)
     FlutterPlatformMessageReleaseResponseHandle(self->engine, response_handle);
 }

 GBytes* fl_engine_send_platform_message_finish(FlEngine* self,
                                                GAsyncResult* result,
                                                GError** error) {
   g_return_val_if_fail(FL_IS_ENGINE(self), FALSE);
   g_return_val_if_fail(g_task_is_valid(result, self), FALSE);

   return static_cast<GBytes*>(g_task_propagate_pointer(G_TASK(result), error));
 }

 void fl_engine_send_window_metrics_event(FlEngine* self,
                                          size_t width,
                                          size_t height,
                                          double pixel_ratio) {
   g_return_if_fail(FL_IS_ENGINE(self));

   FlutterWindowMetricsEvent event = {};
   event.struct_size = sizeof(FlutterWindowMetricsEvent);
   event.width = width;
   event.height = height;
   event.pixel_ratio = pixel_ratio;
   FlutterEngineSendWindowMetricsEvent(self->engine, &event);
 }

 void fl_engine_send_mouse_pointer_event(FlEngine* self,
                                         FlutterPointerPhase phase,
                                         size_t timestamp,
                                         double x,
                                         double y,
                                         int64_t buttons) {
   g_return_if_fail(FL_IS_ENGINE(self));

   FlutterPointerEvent fl_event = {};
   fl_event.struct_size = sizeof(fl_event);
   fl_event.phase = phase;
   fl_event.timestamp = timestamp;
   fl_event.x = x;
   fl_event.y = y;
   fl_event.device_kind = kFlutterPointerDeviceKindMouse;
   fl_event.buttons = buttons;
   FlutterEngineSendPointerEvent(self->engine, &fl_event, 1);
 }

 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;
 }
	// 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/public/flutter_linux/fl_engine.h"
	#include "flutter/shell/platform/linux/fl_engine_private.h"

	#include "flutter/shell/platform/linux/fl_binary_messenger_private.h"
	#include "flutter/shell/platform/linux/fl_renderer.h"

	#include <gmodule.h>

	static constexpr int kMicrosecondsPerNanosecond = 1000;

	// Unique number associated with platform tasks
	static constexpr size_t kPlatformTaskRunnerIdentifier = 1;

	struct _FlEngine {
	GObject parent_instance;

	// Thread the GLib main loop is running on
	GThread* thread;

	FlDartProject* project;
	FlRenderer* renderer;
	FlBinaryMessenger* binary_messenger;
	FLUTTER_API_SYMBOL(FlutterEngine) engine;

	// Function to call when a platform message is received
	FlEnginePlatformMessageHandler platform_message_handler;
	gpointer platform_message_handler_data;
	};

	G_DEFINE_QUARK(fl_engine_error_quark, fl_engine_error)

	G_DEFINE_TYPE(FlEngine, fl_engine, G_TYPE_OBJECT)

	// Subclass of GSource that integrates Flutter tasks into the GLib main loop
	typedef struct {
	GSource parent;
	FlEngine* self;
	FlutterTask task;
	} FlutterSource;

	// Callback to run a Flutter task in the GLib main loop
	static gboolean flutter_source_dispatch(GSource* source,
	GSourceFunc callback,
	gpointer user_data) {
	FlutterSource* fl_source = reinterpret_cast<FlutterSource*>(source);
	FlEngine* self = fl_source->self;

	FlutterEngineResult result =
	FlutterEngineRunTask(self->engine, &fl_source->task);
	if (result != kSuccess)
	g_warning("Failed to run Flutter task\n");

	return G_SOURCE_REMOVE;
	}

	// Table of functions for Flutter GLib main loop integration
	static GSourceFuncs flutter_source_funcs = {
	nullptr, // prepare
	nullptr, // check
	flutter_source_dispatch, // dispatch
	nullptr, // finalize
	nullptr,
	nullptr // Internal usage
	};

	// Flutter engine callbacks

	static void* fl_engine_gl_proc_resolver(void* user_data, const char* name) {
	FlEngine* self = static_cast<FlEngine*>(user_data);
	return fl_renderer_get_proc_address(self->renderer, name);
	}

	static bool fl_engine_gl_make_current(void* user_data) {
	FlEngine* self = static_cast<FlEngine*>(user_data);
	g_autoptr(GError) error = nullptr;
	gboolean result = fl_renderer_make_current(self->renderer, &error);
	if (!result)
	g_warning("%s", error->message);
	return result;
	}

	static bool fl_engine_gl_clear_current(void* user_data) {
	FlEngine* self = static_cast<FlEngine*>(user_data);
	g_autoptr(GError) error = nullptr;
	gboolean result = fl_renderer_clear_current(self->renderer, &error);
	if (!result)
	g_warning("%s", error->message);
	return result;
	}

	static uint32_t fl_engine_gl_get_fbo(void* user_data) {
	FlEngine* self = static_cast<FlEngine*>(user_data);
	return fl_renderer_get_fbo(self->renderer);
	}

	static bool fl_engine_gl_present(void* user_data) {
	FlEngine* self = static_cast<FlEngine*>(user_data);
	g_autoptr(GError) error = nullptr;
	gboolean result = fl_renderer_present(self->renderer, &error);
	if (!result)
	g_warning("%s", error->message);
	return result;
	}

	static bool fl_engine_runs_task_on_current_thread(void* user_data) {
	FlEngine* self = static_cast<FlEngine*>(user_data);
	return self->thread == g_thread_self();
	}

	static void fl_engine_post_task(FlutterTask task,
	uint64_t target_time_nanos,
	void* user_data) {
	FlEngine* self = static_cast<FlEngine*>(user_data);

	g_autoptr(GSource) source =
	g_source_new(&flutter_source_funcs, sizeof(FlutterSource));
	FlutterSource* fl_source = reinterpret_cast<FlutterSource*>(source);
	fl_source->self = self;
	fl_source->task = task;
	g_source_set_ready_time(source,
	target_time_nanos / kMicrosecondsPerNanosecond);
	g_source_attach(source, nullptr);
	}

	static void fl_engine_platform_message_cb(const FlutterPlatformMessage* message,
	void* user_data) {
	FlEngine* self = FL_ENGINE(user_data);

	gboolean handled = FALSE;
	if (self->platform_message_handler != nullptr) {
	g_autoptr(GBytes) data =
	g_bytes_new(message->message, message->message_size);
	handled = self->platform_message_handler(
	self, message->channel, data, message->response_handle,
	self->platform_message_handler_data);
	}

	if (!handled)
	fl_engine_send_platform_message_response(self, message->response_handle,
	nullptr, nullptr);
	}

	static void fl_engine_platform_message_response_cb(const uint8_t* data,
	size_t data_length,
	void* user_data) {
	g_autoptr(GTask) task = G_TASK(user_data);
	g_task_return_pointer(task, g_bytes_new(data, data_length),
	(GDestroyNotify)g_bytes_unref);
	}

	static void fl_engine_dispose(GObject* object) {
	FlEngine* self = FL_ENGINE(object);

	FlutterEngineShutdown(self->engine);

	g_clear_object(&self->project);
	g_clear_object(&self->renderer);
	g_clear_object(&self->binary_messenger);

	G_OBJECT_CLASS(fl_engine_parent_class)->dispose(object);
	}

	static void fl_engine_class_init(FlEngineClass* klass) {
	G_OBJECT_CLASS(klass)->dispose = fl_engine_dispose;
	}

	static void fl_engine_init(FlEngine* self) {
	self->thread = g_thread_self();

	self->binary_messenger = fl_binary_messenger_new(self);
	}

	FlEngine* fl_engine_new(FlDartProject* project, FlRenderer* renderer) {
	g_return_val_if_fail(FL_IS_DART_PROJECT(project), nullptr);
	g_return_val_if_fail(FL_IS_RENDERER(renderer), nullptr);

	FlEngine* self =
	static_cast<FlEngine*>(g_object_new(fl_engine_get_type(), nullptr));
	self->project = static_cast<FlDartProject*>(g_object_ref(project));
	self->renderer = static_cast<FlRenderer*>(g_object_ref(renderer));
	return self;
	}

	gboolean fl_engine_start(FlEngine* self, GError** error) {
	g_return_val_if_fail(FL_IS_ENGINE(self), FALSE);

	if (!fl_renderer_start(self->renderer, error))
	return FALSE;

	FlutterRendererConfig config = {};
	config.type = kOpenGL;
	config.open_gl.struct_size = sizeof(FlutterOpenGLRendererConfig);
	config.open_gl.gl_proc_resolver = fl_engine_gl_proc_resolver;
	config.open_gl.make_current = fl_engine_gl_make_current;
	config.open_gl.clear_current = fl_engine_gl_clear_current;
	config.open_gl.fbo_callback = fl_engine_gl_get_fbo;
	config.open_gl.present = fl_engine_gl_present;

	FlutterTaskRunnerDescription platform_task_runner = {};
	platform_task_runner.struct_size = sizeof(FlutterTaskRunnerDescription);
	platform_task_runner.user_data = self;
	platform_task_runner.runs_task_on_current_thread_callback =
	fl_engine_runs_task_on_current_thread;
	platform_task_runner.post_task_callback = fl_engine_post_task;
	platform_task_runner.identifier = kPlatformTaskRunnerIdentifier;

	FlutterCustomTaskRunners custom_task_runners = {};
	custom_task_runners.struct_size = sizeof(FlutterCustomTaskRunners);
	custom_task_runners.platform_task_runner = &platform_task_runner;

	FlutterProjectArgs args = {};
	args.struct_size = sizeof(FlutterProjectArgs);
	args.assets_path = fl_dart_project_get_assets_path(self->project);
	args.icu_data_path = fl_dart_project_get_icu_data_path(self->project);
	args.platform_message_callback = fl_engine_platform_message_cb;
	args.custom_task_runners = &custom_task_runners;

	FlutterEngineResult result = FlutterEngineInitialize(
	FLUTTER_ENGINE_VERSION, &config, &args, self, &self->engine);
	if (result != kSuccess) {
	g_set_error(error, fl_engine_error_quark(), FL_ENGINE_ERROR_FAILED,
	"Failed to initialize Flutter engine");
	return FALSE;
	}

	result = FlutterEngineRunInitialized(self->engine);
	if (result != kSuccess) {
	g_set_error(error, fl_engine_error_quark(), FL_ENGINE_ERROR_FAILED,
	"Failed to run Flutter engine");
	return FALSE;
	}

	return TRUE;
	}

	void fl_engine_set_platform_message_handler(
	FlEngine* self,
	FlEnginePlatformMessageHandler handler,
	gpointer user_data) {
	g_return_if_fail(FL_IS_ENGINE(self));
	g_return_if_fail(handler != nullptr);

	self->platform_message_handler = handler;
	self->platform_message_handler_data = user_data;
	}

	gboolean fl_engine_send_platform_message_response(
	FlEngine* self,
	const FlutterPlatformMessageResponseHandle* handle,
	GBytes* response,
	GError** error) {
	g_return_val_if_fail(FL_IS_ENGINE(self), FALSE);
	g_return_val_if_fail(handle != nullptr, FALSE);

	gsize data_length = 0;
	const uint8_t* data = nullptr;
	if (response != nullptr)
	data =
	static_cast<const uint8_t*>(g_bytes_get_data(response, &data_length));
	FlutterEngineResult result = FlutterEngineSendPlatformMessageResponse(
	self->engine, handle, data, data_length);

	if (result != kSuccess) {
	g_set_error(error, fl_renderer_error_quark(), FL_RENDERER_ERROR_FAILED,
	"Failed to send platorm message response");
	return FALSE;
	}

	return TRUE;
	}

	void fl_engine_send_platform_message(FlEngine* self,
	const gchar* channel,
	GBytes* message,
	GCancellable* cancellable,
	GAsyncReadyCallback callback,
	gpointer user_data) {
	g_return_if_fail(FL_IS_ENGINE(self));

	GTask* task = nullptr;
	FlutterPlatformMessageResponseHandle* response_handle = nullptr;
	if (callback != nullptr) {
	task = g_task_new(self, cancellable, callback, user_data);

	FlutterEngineResult result = FlutterPlatformMessageCreateResponseHandle(
	self->engine, fl_engine_platform_message_response_cb, task,
	&response_handle);
	if (result != kSuccess) {
	g_task_return_new_error(task, fl_engine_error_quark(),
	FL_ENGINE_ERROR_FAILED,
	"Failed to create response handle");
	g_object_unref(task);
	return;
	}
	}

	FlutterPlatformMessage fl_message = {};
	fl_message.struct_size = sizeof(fl_message);
	fl_message.channel = channel;
	fl_message.message =
	message != nullptr
	? static_cast<const uint8_t*>(g_bytes_get_data(message, nullptr))
	: nullptr;
	fl_message.message_size = message != nullptr ? g_bytes_get_size(message) : 0;
	fl_message.response_handle = response_handle;
	FlutterEngineResult result =
	FlutterEngineSendPlatformMessage(self->engine, &fl_message);

	if (result != kSuccess && task != nullptr) {
	g_task_return_new_error(task, fl_engine_error_quark(),
	FL_ENGINE_ERROR_FAILED,
	"Failed to send platform messages");
	g_object_unref(task);
	}

	if (response_handle != nullptr)
	FlutterPlatformMessageReleaseResponseHandle(self->engine, response_handle);
	}

	GBytes* fl_engine_send_platform_message_finish(FlEngine* self,
	GAsyncResult* result,
	GError** error) {
	g_return_val_if_fail(FL_IS_ENGINE(self), FALSE);
	g_return_val_if_fail(g_task_is_valid(result, self), FALSE);

	return static_cast<GBytes*>(g_task_propagate_pointer(G_TASK(result), error));
	}

	void fl_engine_send_window_metrics_event(FlEngine* self,
	size_t width,
	size_t height,
	double pixel_ratio) {
	g_return_if_fail(FL_IS_ENGINE(self));

	FlutterWindowMetricsEvent event = {};
	event.struct_size = sizeof(FlutterWindowMetricsEvent);
	event.width = width;
	event.height = height;
	event.pixel_ratio = pixel_ratio;
	FlutterEngineSendWindowMetricsEvent(self->engine, &event);
	}

	void fl_engine_send_mouse_pointer_event(FlEngine* self,
	FlutterPointerPhase phase,
	size_t timestamp,
	double x,
	double y,
	int64_t buttons) {
	g_return_if_fail(FL_IS_ENGINE(self));

	FlutterPointerEvent fl_event = {};
	fl_event.struct_size = sizeof(fl_event);
	fl_event.phase = phase;
	fl_event.timestamp = timestamp;
	fl_event.x = x;
	fl_event.y = y;
	fl_event.device_kind = kFlutterPointerDeviceKindMouse;
	fl_event.buttons = buttons;
	FlutterEngineSendPointerEvent(self->engine, &fl_event, 1);
	}

	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;
	}