File indexing completed on 2024-04-28 16:54:58
0001 /* 0002 SPDX-FileCopyrightText: 2021 Aleix Pol Gonzalez <aleixpol@kde.org> 0003 0004 SPDX-License-Identifier: LGPL-2.0-or-later 0005 */ 0006 0007 #pragma once 0008 0009 #include <QAbstractNativeEventFilter> 0010 #include <QObject> 0011 0012 #include <config-plasma.h> 0013 0014 #if HAVE_X11 0015 #include <xcb/xcb.h> 0016 #endif 0017 0018 class QScreen; 0019 class QTimer; 0020 0021 /** 0022 * This class watches for output ordering changes from 0023 * the relevant backend 0024 */ 0025 class OutputOrderWatcher : public QObject 0026 { 0027 Q_OBJECT 0028 public: 0029 /** 0030 * Create the correct OutputOrderWatcher 0031 */ 0032 static OutputOrderWatcher *instance(QObject *parent); 0033 0034 /** 0035 * Returns the list of outputs in order 0036 * 0037 * At the time of change signalling all Screens are 0038 * guaranteed to exist in QGuiApplication. 0039 * 0040 * After screen removal this can temporarily contain 0041 * dead entries. 0042 */ 0043 QStringList outputOrder() const; 0044 0045 /** 0046 * @internal 0047 * For X11 we know libkscreen takes a server grab whilst changing properties. 0048 * This means we know at the time of any runtime screen addition and removal the priorities will 0049 * be up-to-date when we poll them. 0050 * 0051 * For dynamic ordering changes without screen changes we will get the change property multiple times. 0052 * A timer is used to batch them. 0053 * 0054 * A caveat on X11 is the initial startup where plasmashell may query screen information before 0055 * kscreen has set properties. 0056 * This should resolve itself as a dynamic re-ordering when kscreen does start. 0057 * 0058 * For wayland we know kwin sends the priority order whenever screen changes are made. 0059 * As creating screens requires an extra async call to kwin (to bind to the output) 0060 * we always get the new priority ordering before and screen additions. 0061 * We should always have correct values on startup. 0062 */ 0063 virtual void refresh(); 0064 Q_SIGNALS: 0065 void outputOrderChanged(const QStringList &outputOrder); 0066 0067 protected: 0068 OutputOrderWatcher(QObject *parent); 0069 /** 0070 * Backend failed, use QScreen based implementaion 0071 */ 0072 void useFallback(bool fallback); 0073 0074 QStringList m_outputOrder; 0075 bool m_orderProtocolPresent = false; 0076 0077 private: 0078 }; 0079 0080 #if HAVE_X11 0081 class X11OutputOrderWatcher : public OutputOrderWatcher, public QAbstractNativeEventFilter 0082 { 0083 Q_OBJECT 0084 public: 0085 X11OutputOrderWatcher(QObject *parent); 0086 void refresh() override; 0087 0088 protected: 0089 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0) 0090 bool nativeEventFilter(const QByteArray &eventType, void *message, long *result) override; 0091 #else 0092 bool nativeEventFilter(const QByteArray &eventType, void *message, qintptr *result) override; 0093 #endif 0094 private: 0095 QTimer *m_delayTimer = nullptr; // This is just to simulate the protocol that will be guaranteed to always arrive after screens additions and removals 0096 // Xrandr 0097 int m_xrandrExtensionOffset; 0098 xcb_atom_t m_kdeScreenAtom = XCB_ATOM_NONE; 0099 }; 0100 #endif 0101 0102 class WaylandOutputOrderWatcher : public OutputOrderWatcher 0103 { 0104 Q_OBJECT 0105 public: 0106 WaylandOutputOrderWatcher(QObject *parent); 0107 void refresh() override; 0108 0109 private: 0110 bool hasAllScreens() const; 0111 QStringList m_pendingOutputOrder; 0112 };