blob: a958de4d1f3c2d6a1edb1807cab6ee9441902218 (
plain)
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
|
// 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 "ui/gfx/win/dpi.h"
#include <windows.h>
#include "base/win/scoped_hdc.h"
#include "ui/gfx/display.h"
#include "ui/gfx/geometry/point_conversions.h"
#include "ui/gfx/geometry/rect_conversions.h"
#include "ui/gfx/geometry/size_conversions.h"
namespace {
const float kDefaultDPI = 96.f;
float g_device_scale_factor = 0.f;
float GetUnforcedDeviceScaleFactor() {
return g_device_scale_factor ?
g_device_scale_factor :
static_cast<float>(gfx::GetDPI().width()) / kDefaultDPI;
}
} // namespace
namespace gfx {
void SetDefaultDeviceScaleFactor(float scale) {
DCHECK_NE(0.f, scale);
g_device_scale_factor = scale;
}
Size GetDPI() {
static int dpi_x = 0;
static int dpi_y = 0;
static bool should_initialize = true;
if (should_initialize) {
should_initialize = false;
base::win::ScopedGetDC screen_dc(NULL);
// This value is safe to cache for the life time of the app since the
// user must logout to change the DPI setting. This value also applies
// to all screens.
dpi_x = GetDeviceCaps(screen_dc, LOGPIXELSX);
dpi_y = GetDeviceCaps(screen_dc, LOGPIXELSY);
}
return Size(dpi_x, dpi_y);
}
float GetDPIScale() {
if (gfx::Display::HasForceDeviceScaleFactor())
return gfx::Display::GetForcedDeviceScaleFactor();
float dpi_scale = GetUnforcedDeviceScaleFactor();
return (dpi_scale <= 1.25f) ? 1.f : dpi_scale;
}
namespace win {
Point ScreenToDIPPoint(const Point& pixel_point) {
return ScaleToFlooredPoint(pixel_point, 1.0f / GetDPIScale());
}
Point DIPToScreenPoint(const Point& dip_point) {
return ScaleToFlooredPoint(dip_point, GetDPIScale());
}
Rect ScreenToDIPRect(const Rect& pixel_bounds) {
// It's important we scale the origin and size separately. If we instead
// calculated the size from the floored origin and ceiled right the size could
// vary depending upon where the two points land. That would cause problems
// for the places this code is used (in particular mapping from native window
// bounds to DIPs).
return Rect(ScreenToDIPPoint(pixel_bounds.origin()),
ScreenToDIPSize(pixel_bounds.size()));
}
Rect DIPToScreenRect(const Rect& dip_bounds) {
// See comment in ScreenToDIPRect for why we calculate size like this.
return Rect(DIPToScreenPoint(dip_bounds.origin()),
DIPToScreenSize(dip_bounds.size()));
}
Size ScreenToDIPSize(const Size& size_in_pixels) {
// Always ceil sizes. Otherwise we may be leaving off part of the bounds.
return ScaleToCeiledSize(size_in_pixels, 1.0f / GetDPIScale());
}
Size DIPToScreenSize(const Size& dip_size) {
// Always ceil sizes. Otherwise we may be leaving off part of the bounds.
return ScaleToCeiledSize(dip_size, GetDPIScale());
}
int GetSystemMetricsInDIP(int metric) {
// The system metrics always reflect the system DPI, not whatever scale we've
// forced or decided to use.
return static_cast<int>(
std::round(GetSystemMetrics(metric) / GetUnforcedDeviceScaleFactor()));
}
} // namespace win
} // namespace gfx
|
