exo: Fix cursor scaling for 1.25 DSF

components/exo/pointer.cc

 // Copyright 2015 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 "components/exo/pointer.h"
 
 #include <utility>
 
 #include "ash/public/cpp/shell_window_ids.h"
 #include "cc/output/copy_output_request.h"
@@ skipping 43 matching lines @@
   // In particular, the mouse location_f() could differ between the
   // MOUSE_PRESSED and MOUSE_RELEASED events. At MOUSE_RELEASED, it will have a
   // targeter() already cached, while at MOUSE_PRESSED, it will have to
   // calculate it passing through all the hierarchy of windows, and that could
   // generate rounding error. std::numeric_limits<float>::epsilon() is not big
   // enough to catch this rounding error.
   gfx::Vector2dF offset = event->location_f() - location;
   return offset.LengthSquared() < (2 * kLocatedEventEpsilonSquared);
 }
 
-float GetCaptureScale() {
-  float capture_scale = 1.0f;
+display::ManagedDisplayInfo GetCaptureDisplayInfo() {
+  display::ManagedDisplayInfo capture_info;
   for (const auto& display : display::Screen::GetScreen()->GetAllDisplays()) {
     const auto& info = WMHelper::GetInstance()->GetDisplayInfo(display.id());
-    if (info.device_scale_factor() > capture_scale)
-      capture_scale = info.device_scale_factor();
+    if (info.device_scale_factor() >= capture_info.device_scale_factor())
+      capture_info = info;
   }
-  return capture_scale;
+  return capture_info;
 }
 
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 // Pointer, public:
 
 Pointer::Pointer(PointerDelegate* delegate)
     : delegate_(delegate),
       cursor_(ui::CursorType::kNull),
-      capture_scale_(GetCaptureScale()),
+      capture_scale_(GetCaptureDisplayInfo().device_scale_factor()),
+      capture_ratio_(GetCaptureDisplayInfo().GetDensityRatio()),
       cursor_capture_source_id_(base::UnguessableToken::Create()),
       cursor_capture_weak_ptr_factory_(this) {
   auto* helper = WMHelper::GetInstance();
   helper->AddPreTargetHandler(this);
   helper->AddCursorObserver(this);
   helper->AddDisplayConfigurationObserver(this);
 }
 
 Pointer::~Pointer() {
   delegate_->OnPointerDestroying(this);
@@ skipping 177 matching lines @@
 void Pointer::OnCursorDisplayChanged(const display::Display& display) {
   if (focus_)
     UpdateCursor();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // WMHelper::DisplayConfigurationObserver overrides:
 
 void Pointer::OnDisplayConfigurationChanged() {
   UpdatePointerSurface(surface_);
-  capture_scale_ = GetCaptureScale();
+  auto info = GetCaptureDisplayInfo();
+  capture_scale_ = info.device_scale_factor();
+  capture_ratio_ = info.GetDensityRatio();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // SurfaceDelegate overrides:
 
 void Pointer::OnSurfaceCommit() {
   surface_->CommitSurfaceHierarchy();
 
   // Capture new cursor to reflect result of commit.
   if (focus_)
@@ skipping 89 matching lines @@
   UpdateCursor();
 }
 
 void Pointer::UpdateCursor() {
   DCHECK(focus_);
 
   if (cursor_bitmap_.drawsNothing()) {
     cursor_ = ui::CursorType::kNone;
   } else {
     SkBitmap bitmap = cursor_bitmap_;
-    gfx::Point hotspot = gfx::ScaleToFlooredPoint(hotspot_, capture_scale_);
+    gfx::Point hotspot = gfx::ScaleToFlooredPoint(hotspot_, capture_ratio_);
 
     auto* helper = WMHelper::GetInstance();
     const display::Display& display = helper->GetCursorDisplay();
-    float scale = helper->GetDisplayInfo(display.id()).device_scale_factor() /
-                  capture_scale_;
+    float scale =
+        helper->GetDisplayInfo(display.id()).GetDensityRatio() / capture_ratio_;
 
     if (helper->GetCursorSize() == ui::CursorSize::kLarge)
       scale *= kLargeCursorScale;
 
     ui::ScaleAndRotateCursorBitmapAndHotpoint(scale, display.rotation(),
                                               &bitmap, &hotspot);
 
     ui::PlatformCursor platform_cursor;
 #if defined(USE_OZONE)
     // TODO(reveman): Add interface for creating cursors from GpuMemoryBuffers
@@ skipping 17 matching lines @@
   if (!root_window)
     return;
 
   aura::client::CursorClient* cursor_client =
       aura::client::GetCursorClient(root_window);
   if (cursor_client)
     cursor_client->SetCursor(cursor_);
 }
 
 }  // namespace exo