ppapi/cpp/dev/view_dev.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 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_