Pepper_31_C++_interfaces
view_dev.h
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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 PPAPI_CPP_DEV_VIEW_DEV_H_
6 #define PPAPI_CPP_DEV_VIEW_DEV_H_
7 
8 #include "ppapi/cpp/view.h"
9 
10 namespace pp {
11 
12 // ViewDev is a version of View that exposes under-development APIs related to
13 // HiDPI
14 class ViewDev : public View {
15  public:
16  ViewDev() : View() {}
17  ViewDev(const View& other) : View(other) {}
18 
19  virtual ~ViewDev() {}
20 
21  /// GetDeviceScale returns the scale factor between device pixels and DIPs
22  /// (also known as logical pixels or UI pixels on some platforms). This allows
23  /// the developer to render their contents at device resolution, even as
24  /// coordinates / sizes are given in DIPs through the API.
25  ///
26  /// Note that the coordinate system for Pepper APIs is DIPs. Also note that
27  /// one DIP might not equal one CSS pixel - when page scale/zoom is in effect.
28  ///
29  /// @return A <code>float</code> value representing the number of device
30  /// pixels per DIP.
31  float GetDeviceScale() const;
32 
33  /// GetCSSScale returns the scale factor between DIPs and CSS pixels. This
34  /// allows proper scaling between DIPs - as sent via the Pepper API - and CSS
35  /// pixel coordinates used for Web content.
36  ///
37  /// @return A <code>float</code> value representing the number of DIPs per CSS
38  /// pixel.
39  float GetCSSScale() const;
40 };
41 
42 } // namespace pp
43 
44 #endif // PPAPI_CPP_DEV_VIEW_DEV_H_
ViewDev(const View &other)
Definition: view_dev.h:17
Definition: view.h:20
virtual ~ViewDev()
Definition: view_dev.h:19
float GetCSSScale() const
float GetDeviceScale() const