blob: c8d33bfbcb21b35d26550301efe87ddeebb9a241 (
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
|
// Copyright (C) 2019 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
#ifndef QQUICK3DUTILS_P_H
#define QQUICK3DUTILS_P_H
//
// W A R N I N G
// -------------
//
// This file is not part of the Qt API. It exists purely as an
// implementation detail. This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//
#include <type_traits>
#include <QtCore/QtGlobal>
#include <private/qglobal_p.h>
QT_BEGIN_NAMESPACE
template <typename T, typename = void>
struct hasFuzzyCompare : std::false_type {};
template <typename T>
struct hasFuzzyCompare<T, std::void_t<decltype(qFuzzyCompare(std::declval<T &>(), std::declval<T &>()))>> : std::true_type {};
// Assigns 'updated' to 'orig' and returns true if they are different
template <typename T, std::enable_if_t<!hasFuzzyCompare<T>::value, bool> = true>
bool qUpdateIfNeeded(T &orig, T updated)
{
if (orig == updated)
return false;
orig = updated;
return true;
}
// Assigns 'updated' to 'orig' and returns true if they are different, compared with qFuzzyCompare
template <typename T, std::enable_if_t<hasFuzzyCompare<T>::value, bool> = true>
bool qUpdateIfNeeded(T &orig, T updated)
{
if (qFuzzyCompare(orig, updated))
return false;
orig = updated;
return true;
}
QT_END_NAMESPACE
#endif // QQUICK3DUTILS_P_H
|