ui/gfx/display.h

   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/gfx/geometry/rect.h"
  11 #include "ui/gfx/gfx_export.h"
  12
  13 namespace gfx {
  14
  15 // This class typically, but does not always, correspond to a physical display
  16 // connected to the system. A fake Display may exist on a headless system, or a
  17 // Display may correspond to a remote, virtual display.
  18 //
  19 // Note: The screen and display currently uses pixel coordinate
  20 // system. For platforms that support DIP (density independent pixel),
  21 // |bounds()| and |work_area| will return values in DIP coordinate
  22 // system, not in backing pixels.
  23 class GFX_EXPORT Display {
  24  public:
  25   // Screen Rotation in clock-wise degrees.
  26   enum Rotation {
  27     ROTATE_0 = 0,
  28     ROTATE_90,
  29     ROTATE_180,
  30     ROTATE_270,
  31   };
  32
  33   // Touch support for the display.
  34   enum TouchSupport {
  35     TOUCH_SUPPORT_UNKNOWN,
  36     TOUCH_SUPPORT_AVAILABLE,
  37     TOUCH_SUPPORT_UNAVAILABLE,
  38   };
  39
  40   // Creates a display with kInvalidDisplayID as default.
  41   Display();
  42   explicit Display(int64 id);
  43   Display(int64 id, const Rect& bounds);
  44   ~Display();
  45
  46   // Returns the forced device scale factor, which is given by
  47   // "--force-device-scale-factor".
  48   static float GetForcedDeviceScaleFactor();
  49
  50   // Indicates if a device scale factor is being explicitly enforced from the
  51   // command line via "--force-device-scale-factor".
  52   static bool HasForceDeviceScaleFactor();
  53
  54   // Resets the caches used to determine if a device scale factor is being
  55   // forced from the command line via "--force-device-scale-factor", and thus
  56   // ensures that the command line is reevaluated.
  57   static void ResetForceDeviceScaleFactorForTesting();
  58
  59   // Sets/Gets unique identifier associated with the display.
  60   // -1 means invalid display and it doesn't not exit.
  61   int64 id() const { return id_; }
  62   void set_id(int64 id) { id_ = id; }
  63
  64   // Gets/Sets the display's bounds in gfx::Screen's coordinates.
  65   const Rect& bounds() const { return bounds_; }
  66   void set_bounds(const Rect& bounds) { bounds_ = bounds; }
  67
  68   // Gets/Sets the display's work area in gfx::Screen's coordinates.
  69   const Rect& work_area() const { return work_area_; }
  70   void set_work_area(const Rect& work_area) { work_area_ = work_area; }
  71
  72   // Output device's pixel scale factor. This specifies how much the
  73   // UI should be scaled when the actual output has more pixels than
  74   // standard displays (which is around 100~120dpi.) The potential return
  75   // values depend on each platforms.
  76   float device_scale_factor() const { return device_scale_factor_; }
  77   void set_device_scale_factor(float scale) { device_scale_factor_ = scale; }
  78
  79   Rotation rotation() const { return rotation_; }
  80   void set_rotation(Rotation rotation) { rotation_ = rotation; }
  81   int RotationAsDegree() const;
  82   void SetRotationAsDegree(int rotation);
  83
  84   TouchSupport touch_support() const { return touch_support_; }
  85   void set_touch_support(TouchSupport support) { touch_support_ = support; }
  86
  87   // Utility functions that just return the size of display and
  88   // work area.
  89   const Size& size() const { return bounds_.size(); }
  90   const Size& work_area_size() const { return work_area_.size(); }
  91
  92   // Returns the work area insets.
  93   Insets GetWorkAreaInsets() const;
  94
  95   // Sets the device scale factor and display bounds in pixel. This
  96   // updates the work are using the same insets between old bounds and
  97   // work area.
  98   void SetScaleAndBounds(float device_scale_factor,
  99                          const gfx::Rect& bounds_in_pixel);
 100
 101   // Sets the display's size. This updates the work area using the same insets
 102   // between old bounds and work area.
 103   void SetSize(const gfx::Size& size_in_pixel);
 104
 105   // Computes and updates the display's work are using
 106   // |work_area_insets| and the bounds.
 107   void UpdateWorkAreaFromInsets(const gfx::Insets& work_area_insets);
 108
 109   // Returns the display's size in pixel coordinates.
 110   gfx::Size GetSizeInPixel() const;
 111
 112   // Returns a string representation of the display;
 113   std::string ToString() const;
 114
 115   // True if the display contains valid display id.
 116   bool is_valid() const { return id_ != kInvalidDisplayID; }
 117
 118   // True if the display corresponds to internal panel.
 119   bool IsInternal() const;
 120
 121   // Gets/Sets an id of display corresponding to internal panel.
 122   static int64 InternalDisplayId();
 123   static void SetInternalDisplayId(int64 internal_display_id);
 124
 125   static const int64 kInvalidDisplayID;
 126
 127  private:
 128   int64 id_;
 129   Rect bounds_;
 130   Rect work_area_;
 131   float device_scale_factor_;
 132   Rotation rotation_;
 133   TouchSupport touch_support_;
 134 };
 135
 136 }  // namespace gfx
 137
 138 #endif  // UI_GFX_DISPLAY_H_