ash: ozone: apply transformation to events outside the root window

ui/ozone/platform/dri/dri_window.cc

 // Copyright 2014 The Chromium 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 "ui/ozone/platform/dri/dri_window.h"
 
 #include "base/bind.h"
 #include "ui/events/event.h"
 #include "ui/events/ozone/evdev/event_factory_evdev.h"
 #include "ui/events/ozone/events_ozone.h"
@@ skipping 53 matching lines @@
   dri_window_delegate_->OnBoundsChanged(bounds);
 
   if (window_manager_->cursor()->GetCursorWindow() == widget_)
     window_manager_->cursor()->ShowCursor();
 }
 
 gfx::Rect DriWindow::GetBounds() {
   return bounds_;
 }
 
-void DriWindow::SetCapture() {}
+void DriWindow::SetCapture() {
+  window_manager_->GrabMouseEvents(widget_);
+}
 
-void DriWindow::ReleaseCapture() {}
+void DriWindow::ReleaseCapture() {
+  window_manager_->UngrabMouseEvents(widget_);
+}
 
 void DriWindow::ToggleFullscreen() {}
 
 void DriWindow::Maximize() {}
 
 void DriWindow::Minimize() {}
 
 void DriWindow::Restore() {}
 
 void DriWindow::SetCursor(PlatformCursor cursor) {
   window_manager_->cursor()->SetCursor(widget_, cursor);
 }
 
 void DriWindow::MoveCursorTo(const gfx::Point& location) {
   event_factory_->WarpCursorTo(widget_, location);
 }
 
 bool DriWindow::CanDispatchEvent(const PlatformEvent& ne) {
   DCHECK(ne);
   Event* event = static_cast<Event*>(ne);
-  if (event->IsMouseEvent() || event->IsScrollEvent())
+  if (event->IsMouseEvent() || event->IsScrollEvent()) {
+    // Bail out if there is a grab on mouse events.
+    gfx::AcceleratedWidget grabber = window_manager_->mouse_events_grabber();
+    if (grabber != gfx::kNullAcceleratedWidget)
+      return grabber == widget_;
+
+    // Otherwise, just consider the position of the cursor.
     return window_manager_->cursor()->GetCursorWindow() == widget_;
+  }
 
   return true;
 }
 
 uint32_t DriWindow::DispatchEvent(const PlatformEvent& native_event) {
+  // Implement implicit mouse grab on button press
+  Event* event = static_cast<Event*>(native_event);
+  if (event->IsMouseEvent()) {
+    // We need to convert the cursor's position into coordinates

[spang, 2014/11/04 23:27:23]

Can you change DriCursor to generate the event coordinates relative to the
screen, and then just offset here?

So this becomes:

if (event->IsMouseEvent() || event->IsScrollEvent()) {
  LocatedEvent* located_event = static_cast<LocatedEvent*>(event);
  gfx::PointF location = located_event->location();
  location.Offset(-bounds_.Origin());
  located_event->set_location(location);
  located_event->set_location(root_location);
}

+    // relative to the window in case of an implicit grab.
+    if (window_manager_->cursor()->GetCursorWindow() != widget_) {
+      DriWindow* window = window_manager_->GetWindow(
+          window_manager_->cursor()->GetCursorWindow());
+      DCHECK(window);
+      LocatedEvent* located_event = static_cast<LocatedEvent*>(event);
+      gfx::Point event_point = located_event->location();
+      gfx::Point window_origin = GetBounds().origin();
+      gfx::Point cursor_origin = window->GetBounds().origin();
+      located_event->set_location(
+          gfx::Point(event_point.x() + cursor_origin.x() - window_origin.x(),
+                     event_point.y() + cursor_origin.y() - window_origin.y()));
+      located_event->set_root_location(located_event->root_location());
+    }
+  }
   DispatchEventFromNativeUiEvent(
       native_event,
       base::Bind(&PlatformWindowDelegate::DispatchEvent,
                  base::Unretained(delegate_)));
   return POST_DISPATCH_STOP_PROPAGATION;
 }
 
 }  // namespace ui