1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "remoting/host/desktop_resizer.h"
#include <windows.h>
#include <map>
#include "base/logging.h"
#include "base/macros.h"
namespace {
// TODO(jamiewalch): Use the correct DPI for the mode: http://crbug.com/172405.
const int kDefaultDPI = 96;
} // namespace
namespace remoting {
// Provide comparison operation for ScreenResolution so we can use it in
// std::map.
static inline bool operator <(const ScreenResolution& a,
const ScreenResolution& b) {
if (a.dimensions().width() != b.dimensions().width())
return a.dimensions().width() < b.dimensions().width();
if (a.dimensions().height() != b.dimensions().height())
return a.dimensions().height() < b.dimensions().height();
if (a.dpi().x() != b.dpi().x())
return a.dpi().x() < b.dpi().x();
return a.dpi().y() < b.dpi().y();
}
class DesktopResizerWin : public DesktopResizer {
public:
DesktopResizerWin();
~DesktopResizerWin() override;
// DesktopResizer interface.
ScreenResolution GetCurrentResolution() override;
std::list<ScreenResolution> GetSupportedResolutions(
const ScreenResolution& preferred) override;
void SetResolution(const ScreenResolution& resolution) override;
void RestoreResolution(const ScreenResolution& original) override;
private:
static bool IsResizeSupported();
// Calls EnumDisplaySettingsEx() for the primary monitor.
// Returns false if |mode_number| does not exist.
static bool GetPrimaryDisplayMode(
DWORD mode_number, DWORD flags, DEVMODE* mode);
// Returns true if the mode has width, height, bits-per-pixel, frequency
// and orientation fields.
static bool IsModeValid(const DEVMODE& mode);
// Returns the width & height of |mode|, or 0x0 if they are missing.
static ScreenResolution GetModeResolution(const DEVMODE& mode);
std::map<ScreenResolution, DEVMODE> best_mode_for_resolution_;
DISALLOW_COPY_AND_ASSIGN(DesktopResizerWin);
};
DesktopResizerWin::DesktopResizerWin() {
}
DesktopResizerWin::~DesktopResizerWin() {
}
ScreenResolution DesktopResizerWin::GetCurrentResolution() {
DEVMODE current_mode;
if (GetPrimaryDisplayMode(ENUM_CURRENT_SETTINGS, 0, ¤t_mode) &&
IsModeValid(current_mode))
return GetModeResolution(current_mode);
return ScreenResolution();
}
std::list<ScreenResolution> DesktopResizerWin::GetSupportedResolutions(
const ScreenResolution& preferred) {
if (!IsResizeSupported())
return std::list<ScreenResolution>();
// Enumerate the resolutions to return, and where there are multiple modes of
// the same resolution, store the one most closely matching the current mode
// in |best_mode_for_resolution_|.
DEVMODE current_mode;
if (!GetPrimaryDisplayMode(ENUM_CURRENT_SETTINGS, 0, ¤t_mode) ||
!IsModeValid(current_mode))
return std::list<ScreenResolution>();
std::list<ScreenResolution> resolutions;
best_mode_for_resolution_.clear();
for (DWORD i = 0; ; ++i) {
DEVMODE candidate_mode;
if (!GetPrimaryDisplayMode(i, EDS_ROTATEDMODE, &candidate_mode))
break;
// Ignore modes missing the fields that we expect.
if (!IsModeValid(candidate_mode))
continue;
// Ignore modes with differing bits-per-pixel.
if (candidate_mode.dmBitsPerPel != current_mode.dmBitsPerPel)
continue;
// If there are multiple modes with the same dimensions:
// - Prefer the modes which match the current rotation.
// - Among those, prefer modes which match the current frequency.
// - Otherwise, prefer modes with a higher frequency.
ScreenResolution candidate_resolution = GetModeResolution(candidate_mode);
if (best_mode_for_resolution_.count(candidate_resolution) != 0) {
DEVMODE best_mode = best_mode_for_resolution_[candidate_resolution];
if ((candidate_mode.dmDisplayOrientation !=
current_mode.dmDisplayOrientation) &&
(best_mode.dmDisplayOrientation ==
current_mode.dmDisplayOrientation)) {
continue;
}
if ((candidate_mode.dmDisplayFrequency !=
current_mode.dmDisplayFrequency) &&
(best_mode.dmDisplayFrequency >=
candidate_mode.dmDisplayFrequency)) {
continue;
}
} else {
// If we haven't seen this resolution before, add it to those we return.
resolutions.push_back(candidate_resolution);
}
best_mode_for_resolution_[candidate_resolution] = candidate_mode;
}
return resolutions;
}
void DesktopResizerWin::SetResolution(const ScreenResolution& resolution) {
if (best_mode_for_resolution_.count(resolution) == 0)
return;
DEVMODE new_mode = best_mode_for_resolution_[resolution];
DWORD result = ChangeDisplaySettings(&new_mode, CDS_FULLSCREEN);
if (result != DISP_CHANGE_SUCCESSFUL)
LOG(ERROR) << "SetResolution failed: " << result;
}
void DesktopResizerWin::RestoreResolution(const ScreenResolution& original) {
// Restore the display mode based on the registry configuration.
DWORD result = ChangeDisplaySettings(nullptr, 0);
if (result != DISP_CHANGE_SUCCESSFUL)
LOG(ERROR) << "RestoreResolution failed: " << result;
}
// static
bool DesktopResizerWin::IsResizeSupported() {
// Resize is supported only on single-monitor systems.
return GetSystemMetrics(SM_CMONITORS) == 1;
}
// static
bool DesktopResizerWin::GetPrimaryDisplayMode(
DWORD mode_number, DWORD flags, DEVMODE* mode) {
memset(mode, 0, sizeof(DEVMODE));
mode->dmSize = sizeof(DEVMODE);
if (!EnumDisplaySettingsEx(nullptr, mode_number, mode, flags))
return false;
return true;
}
// static
bool DesktopResizerWin::IsModeValid(const DEVMODE& mode) {
const DWORD kRequiredFields =
DM_PELSWIDTH | DM_PELSHEIGHT | DM_BITSPERPEL |
DM_DISPLAYFREQUENCY | DM_DISPLAYORIENTATION;
return (mode.dmFields & kRequiredFields) == kRequiredFields;
}
// static
ScreenResolution DesktopResizerWin::GetModeResolution(const DEVMODE& mode) {
DCHECK(IsModeValid(mode));
return ScreenResolution(
webrtc::DesktopSize(mode.dmPelsWidth, mode.dmPelsHeight),
webrtc::DesktopVector(kDefaultDPI, kDefaultDPI));
}
scoped_ptr<DesktopResizer> DesktopResizer::Create() {
return make_scoped_ptr(new DesktopResizerWin);
}
} // namespace remoting
|
