display.h revision 5821806d5e7f356e8fa4b058a389a808ea183019 
1// Copyright (c) 2012 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 UI_GFX_DISPLAY_H_
6#define UI_GFX_DISPLAY_H_
7
8#include "base/basictypes.h"
9#include "base/compiler_specific.h"
10#include "ui/base/ui_export.h"
11#include "ui/gfx/rect.h"
12
13namespace gfx {
14
15// Note: The screen and display currently uses pixel coordinate
16// system. For platforms that support DIP (density independent pixel),
17// |bounds()| and |work_area| will return values in DIP coordinate
18// system, not in backing pixels.
19class UI_EXPORT Display {
20 public:
21  // Creates a display with kInvalidDisplayID as default.
22  Display();
23  explicit Display(int64 id);
24  Display(int64 id, const Rect& bounds);
25  ~Display();
26
27  // Returns the forced device scale factor, which is given by
28  // "--force-device-scale-factor".
29  static float GetForcedDeviceScaleFactor();
30
31  // Returns 64-bit persistent ID for the specified manufacturer's ID and
32  // serial#.
33  static int64 GetID(uint16 manufacturer_id, uint32 serial_number);
34
35  // Sets/Gets unique identifier associated with the display.
36  // -1 means invalid display and it doesn't not exit.
37  int64 id() const { return id_; }
38  void set_id(int64 id) { id_ = id; }
39
40  // Gets/Sets the display's bounds in gfx::Screen's coordinates.
41  const Rect& bounds() const { return bounds_; }
42  void set_bounds(const Rect& bounds) { bounds_ = bounds; }
43
44  // Gets/Sets the display's work area in gfx::Screen's coordinates.
45  const Rect& work_area() const { return work_area_; }
46  void set_work_area(const Rect& work_area) { work_area_ = work_area; }
47
48  // Output device's pixel scale factor. This specifies how much the
49  // UI should be scaled when the actual output has more pixels than
50  // standard displays (which is around 100~120dpi.) The potential return
51  // values depend on each platforms.
52  float device_scale_factor() const { return device_scale_factor_; }
53  void set_device_scale_factor(float scale) { device_scale_factor_ = scale; }
54
55  // Utility functions that just return the size of display and
56  // work area.
57  const Size& size() const { return bounds_.size(); }
58  const Size& work_area_size() const { return work_area_.size(); }
59
60  // Returns the work area insets.
61  Insets GetWorkAreaInsets() const;
62
63  // Sets the device scale factor and display bounds in pixel. This
64  // updates the work are using the same insets between old bounds and
65  // work area.
66  void SetScaleAndBounds(float device_scale_factor,
67                         const gfx::Rect& bounds_in_pixel);
68
69  // Sets the display's size. This updates the work area using the same insets
70  // between old bounds and work area.
71  void SetSize(const gfx::Size& size_in_pixel);
72
73  // Computes and updates the display's work are using
74  // |work_area_insets| and the bounds.
75  void UpdateWorkAreaFromInsets(const gfx::Insets& work_area_insets);
76
77  // Returns the display's size in pixel coordinates.
78  gfx::Size GetSizeInPixel() const;
79
80#if defined(USE_AURA)
81  // TODO(oshima|skuhne): Eliminate the use of bounds_in_pixel in events_x.cc
82  // and remove bounds_in_pixel from gfx::Display.
83  // Returns the display's bounds in pixel coordinates.
84  const Rect& bounds_in_pixel() const { return bounds_in_pixel_; }
85#endif
86
87  // Returns a string representation of the display;
88  std::string ToString() const;
89
90  // True if the display contains valid display id.
91  bool is_valid() const { return id_ != kInvalidDisplayID; }
92
93  static const int64 kInvalidDisplayID;
94
95 private:
96  int64 id_;
97  Rect bounds_;
98  Rect work_area_;
99#if defined(USE_AURA)
100  Rect bounds_in_pixel_;
101#endif
102  float device_scale_factor_;
103};
104
105}  // namespace gfx
106
107#endif  // UI_GFX_DISPLAY_H_
108