1/*
2 *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#include "modules/desktop_capture/mac/desktop_configuration.h"
12
13#include <math.h>
14#include <algorithm>
15#include <Cocoa/Cocoa.h>
16
17#if !defined(MAC_OS_X_VERSION_10_7) || \
18    MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_7
19
20@interface NSScreen (LionAPI)
21- (CGFloat)backingScaleFactor;
22- (NSRect)convertRectToBacking:(NSRect)aRect;
23@end
24
25#endif  // MAC_OS_X_VERSION_10_7
26
27namespace webrtc {
28
29namespace {
30
31DesktopRect NSRectToDesktopRect(const NSRect& ns_rect) {
32  return DesktopRect::MakeLTRB(
33      static_cast<int>(floor(ns_rect.origin.x)),
34      static_cast<int>(floor(ns_rect.origin.y)),
35      static_cast<int>(ceil(ns_rect.origin.x + ns_rect.size.width)),
36      static_cast<int>(ceil(ns_rect.origin.y + ns_rect.size.height)));
37}
38
39// Inverts the position of |rect| from bottom-up coordinates to top-down,
40// relative to |bounds|.
41void InvertRectYOrigin(const DesktopRect& bounds,
42                       DesktopRect* rect) {
43  assert(bounds.top() == 0);
44  *rect = DesktopRect::MakeXYWH(
45      rect->left(), bounds.bottom() - rect->bottom(),
46      rect->width(), rect->height());
47}
48
49MacDisplayConfiguration GetConfigurationForScreen(NSScreen* screen) {
50  MacDisplayConfiguration display_config;
51
52  // Fetch the NSScreenNumber, which is also the CGDirectDisplayID.
53  NSDictionary* device_description = [screen deviceDescription];
54  display_config.id = static_cast<CGDirectDisplayID>(
55      [[device_description objectForKey:@"NSScreenNumber"] intValue]);
56
57  // Determine the display's logical & physical dimensions.
58  NSRect ns_bounds = [screen frame];
59  display_config.bounds = NSRectToDesktopRect(ns_bounds);
60
61  // If the host is running Mac OS X 10.7+ or later, query the scaling factor
62  // between logical and physical (aka "backing") pixels, otherwise assume 1:1.
63  if ([screen respondsToSelector:@selector(backingScaleFactor)] &&
64      [screen respondsToSelector:@selector(convertRectToBacking:)]) {
65    display_config.dip_to_pixel_scale = [screen backingScaleFactor];
66    NSRect ns_pixel_bounds = [screen convertRectToBacking: ns_bounds];
67    display_config.pixel_bounds = NSRectToDesktopRect(ns_pixel_bounds);
68  } else {
69    display_config.pixel_bounds = display_config.bounds;
70  }
71
72  // Determine if the display is built-in or external.
73  display_config.is_builtin = CGDisplayIsBuiltin(display_config.id);
74
75  return display_config;
76}
77
78}  // namespace
79
80MacDisplayConfiguration::MacDisplayConfiguration() = default;
81MacDisplayConfiguration::MacDisplayConfiguration(
82    const MacDisplayConfiguration& other) = default;
83MacDisplayConfiguration::MacDisplayConfiguration(
84    MacDisplayConfiguration&& other) = default;
85MacDisplayConfiguration::~MacDisplayConfiguration() = default;
86
87MacDisplayConfiguration& MacDisplayConfiguration::operator=(
88    const MacDisplayConfiguration& other) = default;
89MacDisplayConfiguration& MacDisplayConfiguration::operator=(
90    MacDisplayConfiguration&& other) = default;
91
92MacDesktopConfiguration::MacDesktopConfiguration() = default;
93MacDesktopConfiguration::MacDesktopConfiguration(
94    const MacDesktopConfiguration& other) = default;
95MacDesktopConfiguration::MacDesktopConfiguration(
96    MacDesktopConfiguration&& other) = default;
97MacDesktopConfiguration::~MacDesktopConfiguration() = default;
98
99MacDesktopConfiguration& MacDesktopConfiguration::operator=(
100    const MacDesktopConfiguration& other) = default;
101MacDesktopConfiguration& MacDesktopConfiguration::operator=(
102    MacDesktopConfiguration&& other) = default;
103
104// static
105MacDesktopConfiguration MacDesktopConfiguration::GetCurrent(Origin origin) {
106  MacDesktopConfiguration desktop_config;
107
108  NSArray* screens = [NSScreen screens];
109  assert(screens);
110
111  // Iterator over the monitors, adding the primary monitor and monitors whose
112  // DPI match that of the primary monitor.
113  for (NSUInteger i = 0; i < [screens count]; ++i) {
114    MacDisplayConfiguration display_config =
115        GetConfigurationForScreen([screens objectAtIndex: i]);
116
117    if (i == 0)
118      desktop_config.dip_to_pixel_scale = display_config.dip_to_pixel_scale;
119
120    // Cocoa uses bottom-up coordinates, so if the caller wants top-down then
121    // we need to invert the positions of secondary monitors relative to the
122    // primary one (the primary monitor's position is (0,0) in both systems).
123    if (i > 0 && origin == TopLeftOrigin) {
124      InvertRectYOrigin(desktop_config.displays[0].bounds,
125                        &display_config.bounds);
126      // |display_bounds| is density dependent, so we need to convert the
127      // primay monitor's position into the secondary monitor's density context.
128      float scaling_factor = display_config.dip_to_pixel_scale /
129          desktop_config.displays[0].dip_to_pixel_scale;
130      DesktopRect primary_bounds = DesktopRect::MakeLTRB(
131          desktop_config.displays[0].pixel_bounds.left() * scaling_factor,
132          desktop_config.displays[0].pixel_bounds.top() * scaling_factor,
133          desktop_config.displays[0].pixel_bounds.right() * scaling_factor,
134          desktop_config.displays[0].pixel_bounds.bottom() * scaling_factor);
135      InvertRectYOrigin(primary_bounds, &display_config.pixel_bounds);
136    }
137
138    // Add the display to the configuration.
139    desktop_config.displays.push_back(display_config);
140
141    // Update the desktop bounds to account for this display, unless the current
142    // display uses different DPI settings.
143    if (display_config.dip_to_pixel_scale ==
144        desktop_config.dip_to_pixel_scale) {
145      desktop_config.bounds.UnionWith(display_config.bounds);
146      desktop_config.pixel_bounds.UnionWith(display_config.pixel_bounds);
147    }
148  }
149
150  return desktop_config;
151}
152
153// For convenience of comparing MacDisplayConfigurations in
154// MacDesktopConfiguration::Equals.
155bool operator==(const MacDisplayConfiguration& left,
156                const MacDisplayConfiguration& right) {
157  return left.id == right.id &&
158      left.bounds.equals(right.bounds) &&
159      left.pixel_bounds.equals(right.pixel_bounds) &&
160      left.dip_to_pixel_scale == right.dip_to_pixel_scale;
161}
162
163bool MacDesktopConfiguration::Equals(const MacDesktopConfiguration& other) {
164  return bounds.equals(other.bounds) &&
165      pixel_bounds.equals(other.pixel_bounds) &&
166      dip_to_pixel_scale == other.dip_to_pixel_scale &&
167      displays == other.displays;
168}
169
170const MacDisplayConfiguration*
171MacDesktopConfiguration::FindDisplayConfigurationById(
172    CGDirectDisplayID id) {
173  bool is_builtin = CGDisplayIsBuiltin(id);
174  for (MacDisplayConfigurations::const_iterator it = displays.begin();
175      it != displays.end(); ++it) {
176    // The MBP having both discrete and integrated graphic cards will do
177    // automate graphics switching by default. When it switches from discrete to
178    // integrated one, the current display ID of the built-in display will
179    // change and this will cause screen capture stops.
180    // So make screen capture of built-in display continuing even if its display
181    // ID is changed.
182    if ((is_builtin && it->is_builtin) || (!is_builtin && it->id == id)) return &(*it);
183  }
184  return NULL;
185}
186
187}  // namespace webrtc
188