embedder: merge embedder.h from flutter/engine (#408)

Merged from https://github.com/flutter/engine/commits/3.19.0/shell/platform/embedder/embedder.h

Signed-off-by: Hidenori Matsubayashi <Hidenori.Matsubayashi@gmail.com>

src/flutter/common/constants.h

@@ -0,0 +1,38 @@
+// 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_COMMON_CONSTANTS_H_
+#define FLUTTER_COMMON_CONSTANTS_H_
+
+namespace flutter {
+constexpr double kMegaByteSizeInBytes = (1 << 20);
+
+// The ID for the implicit view if the implicit view is enabled.
+//
+// The implicit view is a compatibility mechanism to help the transition from
+// the older single-view APIs to the newer multi-view APIs. The two sets of APIs
+// use different models for view management. The implicit view mechanism allows
+// single-view APIs to operate a special view as if other views don't exist.
+//
+// In the regular multi-view model, all views should be created by
+// `Shell::AddView` before being used, and removed by `Shell::RemoveView` to
+// signify that they are gone. If a view is added or removed, the framework
+// (`PlatformDispatcher`) will be notified. New view IDs are always unique,
+// never reused. Operating a non-existing view is an error.
+//
+// The implicit view is another special view in addition to the "regular views"
+// as above. The shell starts up having the implicit view, which has a fixed
+// view ID of `kFlutterImplicitViewId` and is available throughout the lifetime
+// of the shell. `Shell::AddView` or `RemoveView` must not be called for this
+// view. Even when the window that shows the view is closed, the framework is
+// unaware and might continue rendering into or operating this view.
+//
+// The single-view APIs, which are APIs that do not specify view IDs, operate
+// the implicit view. The multi-view APIs can operate all views, including the
+// implicit view if the target ID is `kFlutterImplicitViewId`, unless specified
+// otherwise.
+constexpr int64_t kFlutterImplicitViewId = 0;
+}  // namespace flutter
+
+#endif  // FLUTTER_COMMON_CONSTANTS_H_

src/flutter/shell/platform/embedder/embedder.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef FLUTTER_EMBEDDER_H_
-#define FLUTTER_EMBEDDER_H_
+#ifndef FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_H_
+#define FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_H_
 
 #include <stdbool.h>
 #include <stddef.h>
@@ -266,6 +266,12 @@ typedef enum {
 
 typedef struct _FlutterEngine* FLUTTER_API_SYMBOL(FlutterEngine);
 
+/// Unique identifier for views.
+///
+/// View IDs are generated by the embedder and are
+/// opaque to the engine; the engine does not interpret view IDs in any way.
+typedef int64_t FlutterViewId;
+
 typedef struct {
   /// horizontal scale factor
   double scaleX;
@@ -961,6 +967,8 @@ typedef struct {
   double scale;
   /// The rotation of the pan/zoom in radians, where 0.0 is the initial angle.
   double rotation;
+  /// The identifier of the view that received the pointer event.
+  FlutterViewId view_id;
 } FlutterPointerEvent;
 
 typedef enum {
@@ -969,6 +977,14 @@ typedef enum {
   kFlutterKeyEventTypeRepeat,
 } FlutterKeyEventType;
 
+typedef enum {
+  kFlutterKeyEventDeviceTypeKeyboard = 1,
+  kFlutterKeyEventDeviceTypeDirectionalPad,
+  kFlutterKeyEventDeviceTypeGamepad,
+  kFlutterKeyEventDeviceTypeJoystick,
+  kFlutterKeyEventDeviceTypeHdmi,
+} FlutterKeyEventDeviceType;
+
 /// A structure to represent a key event.
 ///
 /// Sending `FlutterKeyEvent` via `FlutterEngineSendKeyEvent` results in a
@@ -1032,6 +1048,8 @@ typedef struct {
   /// An event being synthesized means that the `timestamp` might greatly
   /// deviate from the actual time when the event occurs physically.
   bool synthesized;
+  /// The source device for the key event.
+  FlutterKeyEventDeviceType device_type;
 } FlutterKeyEvent;
 
 typedef void (*FlutterKeyEventCallback)(bool /* handled */,
@@ -2253,6 +2271,8 @@ typedef struct {
 
 #ifndef FLUTTER_ENGINE_NO_PROTOTYPES
 
+// NOLINTBEGIN(google-objc-function-naming)
+
 //------------------------------------------------------------------------------
 /// @brief      Creates the necessary data structures to launch a Flutter Dart
 ///             application in AOT mode. The data may only be collected after
@@ -3124,8 +3144,10 @@ FLUTTER_EXPORT
 FlutterEngineResult FlutterEngineGetProcAddresses(
     FlutterEngineProcTable* table);
 
+// NOLINTEND(google-objc-function-naming)
+
 #if defined(__cplusplus)
 }  // extern "C"
 #endif
 
-#endif  // FLUTTER_EMBEDDER_H_
+#endif  // FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_H_

src/flutter/shell/platform/embedder/embedder_struct_macros.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_SAFE_ACCESS_H_
-#define FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_SAFE_ACCESS_H_
+#ifndef FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_STRUCT_MACROS_H_
+#define FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_STRUCT_MACROS_H_
 
 #include <type_traits>
 
@@ -29,4 +29,4 @@
 #define SAFE_EXISTS_ONE_OF(pointer, member1, member2) \
   (SAFE_EXISTS(pointer, member1) != SAFE_EXISTS(pointer, member2))
 
-#endif  // FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_SAFE_ACCESS_H_
+#endif  // FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_STRUCT_MACROS_H_

src/flutter/shell/platform/linux_embedded/flutter_elinux_view.cc

@@ -7,6 +7,7 @@
 #include <chrono>
 #include <cmath>
 
+#include "flutter/common/constants.h"
 #include "flutter/shell/platform/linux_embedded/logger.h"
 
 namespace flutter {
@@ -165,6 +166,9 @@ void FlutterELinuxView::OnTouchDown(uint32_t time,
       .scroll_delta_y = 0,
       .device_kind = kFlutterPointerDeviceKindTouch,
       .buttons = 0,
+      // TODO: Use the correct view ID for pointer events once the
+      // eLinux embedder supports multiple views.
+      .view_id = flutter::kFlutterImplicitViewId,
   };
   engine_->SendPointerEvent(event);
 }
@@ -203,6 +207,9 @@ void FlutterELinuxView::OnTouchUp(uint32_t time, int32_t id) {
       .scroll_delta_y = 0,
       .device_kind = kFlutterPointerDeviceKindTouch,
       .buttons = 0,
+      // TODO: Use the correct view ID for pointer events once the
+      // eLinux embedder supports multiple views.
+      .view_id = flutter::kFlutterImplicitViewId,
   };
   engine_->SendPointerEvent(event);
 }
@@ -247,6 +254,9 @@ void FlutterELinuxView::OnTouchMotion(uint32_t time,
       .scroll_delta_y = 0,
       .device_kind = kFlutterPointerDeviceKindTouch,
       .buttons = 0,
+      // TODO: Use the correct view ID for pointer events once the
+      // eLinux embedder supports multiple views.
+      .view_id = flutter::kFlutterImplicitViewId,
   };
   engine_->SendPointerEvent(event);
 }
@@ -424,6 +434,9 @@ void FlutterELinuxView::SendPointerEventWithData(
   FlutterPointerEvent event = event_data;
   event.device_kind = kFlutterPointerDeviceKindMouse;
   event.buttons = mouse_state_.buttons;
+  // TODO: Use the correct view ID for pointer events once the
+  // eLinux embedder supports multiple views.
+  event.view_id = flutter::kFlutterImplicitViewId;
 
   // Set metadata that's always the same regardless of the event.
   event.struct_size = sizeof(event);