[Touch emulator] Update cursor when device scale factor changes.

content/browser/renderer_host/input/touch_emulator.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 "content/browser/renderer_host/input/touch_emulator.h"
 
 #include "build/build_config.h"
 #include "content/browser/renderer_host/input/motion_event_web.h"
 #include "content/common/input/web_touch_event_traits.h"
 #include "content/grit/content_resources.h"
@@ skipping 38 matching lines @@
 const double kMouseMoveDropIntervalSeconds = 5.f / 1000;
 
 } // namespace
 
 TouchEmulator::TouchEmulator(TouchEmulatorClient* client,
                              float device_scale_factor)
     : client_(client),
       gesture_provider_config_type_(
           ui::GestureProviderConfigType::CURRENT_PLATFORM),
       double_tap_enabled_(true),
+      use_2x_cursors_(false),
       emulated_stream_active_sequence_count_(0),
       native_stream_active_sequence_count_(0) {
   DCHECK(client_);
   ResetState();
-
-  bool use_2x = device_scale_factor > 1.5f;
-  float cursor_scale_factor = use_2x ? 2.f : 1.f;
-  cursor_size_ = InitCursorFromResource(&touch_cursor_,
-      cursor_scale_factor,
-      use_2x ? IDR_DEVTOOLS_TOUCH_CURSOR_ICON_2X :
-          IDR_DEVTOOLS_TOUCH_CURSOR_ICON);
-  InitCursorFromResource(&pinch_cursor_,
-      cursor_scale_factor,
-      use_2x ? IDR_DEVTOOLS_PINCH_CURSOR_ICON_2X :
-          IDR_DEVTOOLS_PINCH_CURSOR_ICON);
-
-  WebCursor::CursorInfo cursor_info;
-  cursor_info.type = blink::WebCursorInfo::TypePointer;
-  pointer_cursor_.InitFromCursorInfo(cursor_info);
+  InitCursors(device_scale_factor, true);
 }
 
 TouchEmulator::~TouchEmulator() {
   // We cannot cleanup properly in destructor, as we need roundtrip to the
   // renderer for ack. Instead, the owner should call Disable, and only
   // destroy this object when renderer is dead.
 }
 
 void TouchEmulator::ResetState() {
   last_mouse_event_was_move_ = false;
@@ skipping 20 matching lines @@
 void TouchEmulator::Disable() {
   if (!enabled())
     return;
 
   CancelTouch();
   gesture_provider_.reset();
   UpdateCursor();
   ResetState();
 }
 
+void TouchEmulator::SetDeviceScaleFactor(float device_scale_factor) {
+  if (!InitCursors(device_scale_factor, false))
+    return;
+  if (enabled())
+    UpdateCursor();
+}
+
 void TouchEmulator::SetDoubleTapSupportForPageEnabled(bool enabled) {
   double_tap_enabled_ = enabled;
   if (gesture_provider_)
     gesture_provider_->SetDoubleTapSupportForPageEnabled(enabled);
 }
 
+bool TouchEmulator::InitCursors(float device_scale_factor, bool force) {
+  bool use_2x = device_scale_factor > 1.5f;
+  if (use_2x == use_2x_cursors_ && !force)
+    return false;
+  use_2x_cursors_ = use_2x;
+  float cursor_scale_factor = use_2x ? 2.f : 1.f;
+  cursor_size_ = InitCursorFromResource(&touch_cursor_,
+      cursor_scale_factor,
+      use_2x ? IDR_DEVTOOLS_TOUCH_CURSOR_ICON_2X :
+          IDR_DEVTOOLS_TOUCH_CURSOR_ICON);
+  InitCursorFromResource(&pinch_cursor_,
+      cursor_scale_factor,
+      use_2x ? IDR_DEVTOOLS_PINCH_CURSOR_ICON_2X :
+          IDR_DEVTOOLS_PINCH_CURSOR_ICON);
+
+  WebCursor::CursorInfo cursor_info;
+  cursor_info.type = blink::WebCursorInfo::TypePointer;
+  pointer_cursor_.InitFromCursorInfo(cursor_info);
+  return true;
+}
+
 gfx::SizeF TouchEmulator::InitCursorFromResource(
     WebCursor* cursor, float scale, int resource_id) {
   gfx::Image& cursor_image =
       content::GetContentClient()->GetNativeImageNamed(resource_id);
   WebCursor::CursorInfo cursor_info;
   cursor_info.type = blink::WebCursorInfo::TypeCustom;
   cursor_info.image_scale_factor = scale;
   cursor_info.custom_image = cursor_image.AsBitmap();
   cursor_info.hotspot =
       gfx::Point(cursor_image.Width() / 2, cursor_image.Height() / 2);
@@ skipping 318 matching lines @@
   point.tiltX = 0;
   point.tiltY = 0;
   point.pointerType = blink::WebPointerProperties::PointerType::Touch;
 }
 
 bool TouchEmulator::InPinchGestureMode() const {
   return shift_pressed_;
 }
 
 }  // namespace content