remoting/host/screen_resolution.cc

   1 // Copyright (c) 2013 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 #include "remoting/host/screen_resolution.h"
   6
   7 #include <algorithm>
   8 #include <limits>
   9
  10 #include "base/logging.h"
  11
  12 namespace remoting {
  13
  14 ScreenResolution::ScreenResolution()
  15     : dimensions_(webrtc::DesktopSize(0, 0)),
  16       dpi_(webrtc::DesktopVector(0, 0)) {
  17 }
  18
  19 ScreenResolution::ScreenResolution(const webrtc::DesktopSize& dimensions,
  20                                    const webrtc::DesktopVector& dpi)
  21     : dimensions_(dimensions),
  22       dpi_(dpi) {
  23   // Check that dimensions are not negative.
  24   DCHECK(!dimensions.is_empty() || dimensions.equals(webrtc::DesktopSize()));
  25   DCHECK_GE(dpi.x(), 0);
  26   DCHECK_GE(dpi.y(), 0);
  27 }
  28
  29 webrtc::DesktopSize ScreenResolution::ScaleDimensionsToDpi(
  30     const webrtc::DesktopVector& new_dpi) const {
  31   int64 width = dimensions_.width();
  32   int64 height = dimensions_.height();
  33
  34   // Scale the screen dimensions to new DPI.
  35   width = std::min(width * new_dpi.x() / dpi_.x(),
  36                    static_cast<int64>(std::numeric_limits<int32>::max()));
  37   height = std::min(height * new_dpi.y() / dpi_.y(),
  38                     static_cast<int64>(std::numeric_limits<int32>::max()));
  39   return webrtc::DesktopSize(width, height);
  40 }
  41
  42 bool ScreenResolution::IsEmpty() const {
  43   return dimensions_.is_empty() || dpi_.is_zero();
  44 }
  45
  46 bool ScreenResolution::Equals(const ScreenResolution& other) const {
  47   return dimensions_.equals(other.dimensions()) && dpi_.equals(other.dpi());
  48 }
  49
  50 }  // namespace remoting