remoting/host/chromeos/point_transformer.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef REMOTING_HOST_CHROMEOS_POINT_TRANSFORMER_H_
   6 #define REMOTING_HOST_CHROMEOS_POINT_TRANSFORMER_H_
   7
   8 #include "ui/aura/window_observer.h"
   9 #include "ui/gfx/geometry/point_f.h"
  10 #include "ui/gfx/transform.h"
  11
  12 namespace aura {
  13 class Window;
  14 }  // namespace aura
  15
  16 namespace remoting {
  17
  18 // A class that performs coordinate transformations between the root window
  19 // coordinates and the native screen coordinates, according to the current
  20 // display rotation settings.
  21 //
  22 // Root window coordinates are expressed relative to the top left corner of the
  23 // root window whereas native screen coordinates are expressed relative to the
  24 // top left corner of the frame buffer, which may not match the root window
  25 // either in origin nor orientation.  Both coordinate systems are always in
  26 // device pixels.
  27 //
  28 // For example, when the display is rotated by 90 deg, the pixel at root window
  29 // coordinates (x, y) will have native screen coordinates (height - y, x).
  30 class PointTransformer : public aura::WindowObserver {
  31  public:
  32   PointTransformer();
  33   ~PointTransformer() override;
  34
  35   // Converts from root window coordinates to native screen coordinates.
  36   gfx::PointF ToScreenCoordinates(const gfx::PointF& window_location);
  37
  38   // Converts from native screen coordinates to root window coordinates.
  39   gfx::PointF FromScreenCoordinates(const gfx::PointF& screen_location);
  40
  41  private:
  42   // aura::WindowObserver interface.
  43   void OnWindowTransformed(aura::Window* window) override;
  44
  45   aura::Window* root_window_;
  46   gfx::Transform root_to_screen_;
  47   gfx::Transform screen_to_root_;
  48
  49   DISALLOW_COPY_AND_ASSIGN(PointTransformer);
  50 };
  51
  52 }  // namespace remoting
  53
  54 #endif  // REMOTING_HOST_CHROMEOS_POINT_TRANSFORMER_H_