Add an engine API that knows about screens.

Author: gspencergoog

ci/licenses_golden/licenses_flutter

@@ -410,6 +410,10 @@ FILE: ../../../flutter/lib/ui/window/pointer_data_packet.h
 FILE: ../../../flutter/lib/ui/window/pointer_data_packet_converter.cc
 FILE: ../../../flutter/lib/ui/window/pointer_data_packet_converter.h
 FILE: ../../../flutter/lib/ui/window/pointer_data_packet_converter_unittests.cc
+FILE: ../../../flutter/lib/ui/window/screen.cc
+FILE: ../../../flutter/lib/ui/window/screen.h
+FILE: ../../../flutter/lib/ui/window/screen_metrics.cc
+FILE: ../../../flutter/lib/ui/window/screen_metrics.h
 FILE: ../../../flutter/lib/ui/window/viewport_metrics.cc
 FILE: ../../../flutter/lib/ui/window/viewport_metrics.h
 FILE: ../../../flutter/lib/ui/window/window.cc

examples/glfw/FlutterEmbedderGLFW.cc

@@ -68,14 +68,43 @@ static void GLFWKeyCallback(GLFWwindow* window,
 }
 
 void GLFWwindowSizeCallback(GLFWwindow* window, int width, int height) {
+  int left, top;
+  glfwGetWindowPos(window, &left, &top);
   FlutterWindowMetricsEvent event = {};
   event.struct_size = sizeof(event);
+  event.window_id = 0;
+  event.left = left * g_pixelRatio;
+  event.top = top * g_pixelRatio;
   event.width = width * g_pixelRatio;
   event.height = height * g_pixelRatio;
   event.pixel_ratio = g_pixelRatio;
+
+  // TODO(gspencergoog): Currently, there is only one window. This will change
+  // as multi-window support is added. See
+  // https://github.com/flutter/flutter/issues/60131
+  FlutterEngineSendWindowMetricsEvent(
+      reinterpret_cast<FlutterEngine>(glfwGetWindowUserPointer(window)),
+      &event, 1);
+}
+
+void GLFWwindowPosCallback(GLFWwindow* window, int left, int top) {
+  int width, height;
+  glfwGetWindowSize(window, &width, &height);
+  FlutterWindowMetricsEvent event = {};
+  event.struct_size = sizeof(event);
+  event.window_id = 0;
+  event.left = left * g_pixelRatio;
+  event.top = top * g_pixelRatio;
+  event.width = width * g_pixelRatio;
+  event.height = height * g_pixelRatio;
+  event.pixel_ratio = g_pixelRatio;
+
+  // TODO(gspencergoog): Currently, there is only one window. This will change
+  // as multi-window support is added. See
+  // https://github.com/flutter/flutter/issues/60131
   FlutterEngineSendWindowMetricsEvent(
       reinterpret_cast<FlutterEngine>(glfwGetWindowUserPointer(window)),
-      &event);
+      &event, 1);
 }
 
 bool RunFlutter(GLFWwindow* window,
@@ -150,6 +179,7 @@ int main(int argc, const char* argv[]) {
 
   glfwSetKeyCallback(window, GLFWKeyCallback);
   glfwSetWindowSizeCallback(window, GLFWwindowSizeCallback);
+  glfwSetWindowPosCallback(window, GLFWwindowPosCallback);
   glfwSetMouseButtonCallback(window, GLFWmouseButtonCallback);
 
   while (!glfwWindowShouldClose(window)) {

lib/ui/BUILD.gn

@@ -103,6 +103,10 @@ source_set_maybe_fuchsia_legacy("ui") {
     "window/pointer_data_packet.h",
     "window/pointer_data_packet_converter.cc",
     "window/pointer_data_packet_converter.h",
+    "window/screen.cc",
+    "window/screen.h",
+    "window/screen_metrics.cc",
+    "window/screen_metrics.h",
     "window/viewport_metrics.cc",
     "window/viewport_metrics.h",
     "window/window.cc",

lib/ui/compositing/scene.cc

@@ -42,10 +42,13 @@ Scene::Scene(std::shared_ptr<flutter::Layer> rootLayer,
              uint32_t rasterizerTracingThreshold,
              bool checkerboardRasterCacheImages,
              bool checkerboardOffscreenLayers) {
+  // TODO(gspencergoog): Currently, there is only one window. This will change
+  // as multi-window support is added. See
+  // https://github.com/flutter/flutter/issues/60131
   auto viewport_metrics = UIDartState::Current()
                               ->platform_configuration()
-                              ->get_window()
-                              .viewport_metrics();
+                              ->get_window(0)
+                              ->viewport_metrics();
 
   layer_tree_ = std::make_unique<LayerTree>(
       SkISize::Make(viewport_metrics.physical_width,

lib/ui/hooks.dart

@@ -11,7 +11,10 @@ part of dart.ui;
 @pragma('vm:entry-point')
 // ignore: unused_element
 void _updateWindowMetrics(
+  Object windowId,
   double devicePixelRatio,
+  double left,
+  double top,
   double width,
   double height,
   double depth,
@@ -28,25 +31,6 @@ void _updateWindowMetrics(
   double systemGestureInsetBottom,
   double systemGestureInsetLeft,
 ) {
-  print('''
-Updated window metrics:
-  devicePixelRatio: $devicePixelRatio
-  width: $width
-  height: $height
-  depth: $depth
-  viewPaddingTop: $viewPaddingTop
-  viewPaddingRight: $viewPaddingRight
-  viewPaddingBottom: $viewPaddingBottom
-  viewPaddingLeft: $viewPaddingLeft
-  viewInsetTop: $viewInsetTop
-  viewInsetRight: $viewInsetRight
-  viewInsetBottom: $viewInsetBottom
-  viewInsetLeft: $viewInsetLeft
-  systemGestureInsetTop: $systemGestureInsetTop
-  systemGestureInsetRight: $systemGestureInsetRight
-  systemGestureInsetBottom: $systemGestureInsetBottom
-  systemGestureInsetLeft: $systemGestureInsetLeft
-''');
   window
     .._devicePixelRatio = devicePixelRatio
     .._physicalSize = Size(width, height)
@@ -74,6 +58,48 @@ Updated window metrics:
   _invoke(window.onMetricsChanged, window._onMetricsChangedZone);
 }
 
+@pragma('vm:entry-point')
+// ignore: unused_element
+void _removeWindows(List<Object> removedIds) {
+  // TODO(gspencergoog): Remove given IDs from screen metrics once dart::ui
+  // understands screens. See https://github.com/flutter/flutter/issues/60131
+  print('Removed windows: $removedIds');
+}
+
+@pragma('vm:entry-point')
+// ignore: unused_element
+void _updateScreenMetrics(
+    Object screenId,
+    double left,
+    double top,
+    double width,
+    double height,
+    double devicePixelRatio,
+    double viewPaddingTop,
+    double viewPaddingRight,
+    double viewPaddingBottom,
+    double viewPaddingLeft,
+    double viewInsetTop,
+    double viewInsetRight,
+    double viewInsetBottom,
+    double viewInsetLeft,
+    double systemGestureInsetTop,
+    double systemGestureInsetRight,
+    double systemGestureInsetBottom,
+    double systemGestureInsetLeft,
+    ) {
+  // TODO(gspencergoog): Once dart:ui understands screens, set their metrics
+  // here. See https://github.com/flutter/flutter/issues/60131
+}
+
+@pragma('vm:entry-point')
+// ignore: unused_element
+void _removeScreens(List<Object> removedIds) {
+  // TODO(gspencergoog): Remove given IDs from screen metrics once dart::ui
+  // understands screens. See https://github.com/flutter/flutter/issues/60131
+  print('Removed screens: $removedIds');
+}
+
 typedef _LocaleClosure = String? Function();
 
 String? _localeClosure() {

lib/ui/painting/canvas.cc

@@ -426,10 +426,13 @@ void Canvas::drawShadow(const CanvasPath* path,
     Dart_ThrowException(
         ToDart("Canvas.drawShader called with non-genuine Path."));
   }
+  // TODO(gspencergoog): Currently, there is only one window. This will change
+  // as multi-window support is added. See
+  // https://github.com/flutter/flutter/issues/60131
   SkScalar dpr = UIDartState::Current()
                      ->platform_configuration()
-                     ->get_window()
-                     .viewport_metrics()
+                     ->get_window(0)
+                     ->viewport_metrics()
                      .device_pixel_ratio;
   external_allocation_size_ += path->path().approximateBytesUsed();
   flutter::PhysicalShapeLayer::DrawShadow(canvas_, path->path(), color,

lib/ui/window/platform_configuration.cc

@@ -7,7 +7,9 @@
 #include "flutter/lib/ui/compositing/scene.h"
 #include "flutter/lib/ui/ui_dart_state.h"
 #include "flutter/lib/ui/window/platform_message_response_dart.h"
+#include "flutter/lib/ui/window/screen.h"
 #include "flutter/lib/ui/window/window.h"
+#include "lib/ui/window/screen_metrics.h"
 #include "third_party/tonic/converter/dart_converter.h"
 #include "third_party/tonic/dart_args.h"
 #include "third_party/tonic/dart_library_natives.h"
@@ -188,7 +190,7 @@ PlatformConfigurationClient::~PlatformConfigurationClient() {}
 
 PlatformConfiguration::PlatformConfiguration(
     PlatformConfigurationClient* client)
-    : client_(client), window_(new Window({1.0, 0.0, 0.0})) {}
+    : client_(client) {}
 
 PlatformConfiguration::~PlatformConfiguration() {}
 
@@ -197,11 +199,6 @@ void PlatformConfiguration::DidCreateIsolate() {
                Dart_LookupLibrary(tonic::ToDart("dart:ui")));
 }
 
-void PlatformConfiguration::SetWindowMetrics(
-    const ViewportMetrics& window_metrics) {
-  window_->UpdateWindowMetrics(library_, window_metrics);
-}
-
 void PlatformConfiguration::UpdateLocales(
     const std::vector<std::string>& locales) {
   std::shared_ptr<tonic::DartState> dart_state = library_.dart_state().lock();
@@ -439,4 +436,102 @@ void PlatformConfiguration::RegisterNatives(
   });
 }
 
+void PlatformConfiguration::SetWindowMetrics(
+    const std::vector<ViewportMetrics>& window_metrics) {
+  WindowMap updated;
+  for (const auto& metrics : window_metrics) {
+    WindowMap::iterator found = windows_.find(metrics.view_id);
+    if (found == windows_.end()) {
+      // A new window that needs to be added
+      std::shared_ptr<Window> new_window = std::make_shared<Window>(metrics);
+      updated.insert(std::make_pair(metrics.view_id, new_window));
+      new_window->UpdateWindowMetrics(library_, metrics);
+    } else {
+      // An existing window that needs to be updated, add it to the updated
+      // list, and remove it from the existing screens.
+      (*found).second->UpdateWindowMetrics(library_, metrics);
+      updated.insert(*found);
+      windows_.erase(found);
+    }
+  }
+
+  // Anything left in windows_ didn't exist in the window_metrics supplied, and
+  // so will be removed.
+  std::vector<int64_t> removed_ids;
+  for (const auto& entry : windows_) {
+    removed_ids.push_back(entry.first);
+  }
+
+  windows_.swap(updated);
+
+  std::shared_ptr<tonic::DartState> dart_state = library_.dart_state().lock();
+  if (!dart_state) {
+    return;
+  }
+  tonic::DartState::Scope scope(dart_state);
+  if (!removed_ids.empty()) {
+    tonic::LogIfError(tonic::DartInvokeField(library_.value(), "_removeWindows",
+                                             {
+                                                 tonic::ToDart(removed_ids),
+                                             }));
+  }
+}
+
+void PlatformConfiguration::SetScreenMetrics(
+    const std::vector<ScreenMetrics>& screen_metrics) {
+  ScreenMap updated;
+  for (const auto& metrics : screen_metrics) {
+    ScreenMap::iterator found = screens_.find(metrics.screen_id);
+    if (found == screens_.end()) {
+      // A new screen that needs to be added
+      std::shared_ptr<Screen> new_screen = std::make_shared<Screen>(metrics);
+      updated.insert(std::make_pair(metrics.screen_id, new_screen));
+      new_screen->UpdateScreenMetrics(library_, metrics);
+    } else {
+      // An existing screen that needs to be updated, add it to the updated
+      // list, and remove it from the existing screens.
+      (*found).second->UpdateScreenMetrics(library_, metrics);
+      updated.insert(*found);
+      screens_.erase(found);
+    }
+  }
+
+  // Anything left in screens_ didn't exist in the screen_metrics supplied, and
+  // so will be removed.
+  std::vector<int64_t> removed_ids;
+  for (const auto& entry : screens_) {
+    removed_ids.push_back(entry.first);
+  }
+
+  screens_.swap(updated);
+
+  std::shared_ptr<tonic::DartState> dart_state = library_.dart_state().lock();
+  if (!dart_state) {
+    return;
+  }
+  tonic::DartState::Scope scope(dart_state);
+  if (!removed_ids.empty()) {
+    tonic::LogIfError(tonic::DartInvokeField(library_.value(), "_removeScreens",
+                                             {
+                                                 tonic::ToDart(removed_ids),
+                                             }));
+  }
+}
+
+std::shared_ptr<Window> PlatformConfiguration::get_window(int64_t window_id) {
+  if (windows_.find(window_id) == windows_.end()) {
+    FML_DLOG(WARNING) << "Unable to find window with id " << window_id;
+    return nullptr;
+  }
+  return windows_.at(window_id);
+}
+
+std::shared_ptr<Screen> PlatformConfiguration::get_screen(int64_t screen_id) {
+  if (screens_.find(screen_id) == screens_.end()) {
+    FML_DLOG(WARNING) << "Unable to find screen with id " << screen_id;
+    return nullptr;
+  }
+  return screens_.at(screen_id);
+}
+
 }  // namespace flutter