Add Qt6 Support (#7339)

* Rebase against master

Co-authored-by: michaelgregorius <michael.gregorius.git@arcor.de>
Co-authored-by: Rossmaxx <74815851+Rossmaxx@users.noreply.github.com>

* Fix Qt6 DMG on Apple (#7240)

- Fix linking issues with Qt Framework files
- Fix qmake detection

* Fixes after rebase

* Fix embed.cpp compilation

Fix implicit conversion from int when using QString.arg(...)

* Fix Qt6 signature change for nativeEventFilter (#7254)

* Adds win32EventFilter a wrapper for nativeEventFilter on Windows
* win32EventFilter is currently used to intercept top-level Window events (currently, to avoid VSTs setting transparency of the parent application)

* fix broken signal slot connections (#7274)

QComboBox activated() replaced with textActivated() since Qt 5.14

* Enabled VSTs on Qt 6 (#7273)

* enabled VST support for Qt 6 builds
* Note : Embedding on QT6 will be buggy on linux as a result of using qt embedding, which unfortunately is a qt bug which hasn't been resolved.

* Changed bar lines to follow snap size (#7034)

* Added lines in between bars
* Changed bar lines to follow snap size
* Changed default zoom and quantization value
* Added constants for line widths
* Added QSS configuration for new grid line colors
* Tied line widths to QSS properties
* Changed default quantization to 1/4
* Removed clear() from destructor model
* Removed destructor in ComboBoxModel.h
* Changed member set/get functions to pass by value
* Updated signal connection with newer syntax

* Fix compilation

* Fix MSVC builds

* fix nullptr deref in AudioFileProcessor (qt6 branch) (#7532)

* ensured mouse event != nullptr before deref

* separation of concerns: AFP WaveView updateCursor

extract check to pointerCloseToStartEndOrLoop()

* marked some function parameters as const

* Remove Core5Compat usage

* Fix bad merge

* Fixes after rebase

* Simplify QTX_WRAP_CPP call

* Remove comments that are obvious to a developer

* Whitespace

* Try using Qt 6 for MSVC CI

I chose Qt 6.5 because it's the last Qt LTS release with declared
support for Visual Studio 2019. Once we upgrade to Visual Studio 2022,
we could upgrade Qt as well.

* Fix MSVC build

Also fixes two memory leaks in MidiWinMM

* Fix GuiApplication on MSVC

* Fix interpolateInRgb

* Try building with patched Calf

* Fix submodule

* Fix OpulenZ build

* Try to fix zyn

* Fix comment

* Ty to fix zyn (again)

* Ty to fix RemotePluginBase

* Revert "Ty to fix RemotePluginBase"

This reverts commit 92dac44ffb11e19d1d5a21d9155369f017bd59e9.

* Update plugins/ZynAddSubFx/CMakeLists.txt

Co-authored-by: Dalton Messmer <messmer.dalton@gmail.com>

* Fix vertical & horizontal scroll wheel in SongEditor

* AppImage: Fix finding of Qt6 libs

* Fix implicit QString --> QFileInfo conversion

* Point submodule to lmms

* Fix multiple deprecation warnings

* Fix for Clang compiler

* Build with latest Qt LTS version now that we use MSVC 2022

* Update jurplel/install-qt-action to v4.3.0

* Bump minimum Qt6 version for MSVC

* Fix incorrect Qt version checks

Some comparisons were using ">" rather than ">="

* `QSize()` != `QSize(0, 0)`

* Fix more deprecation warnings

* Fix style

* Simplify Spectrum Analyzer mouse events

The Qt bug that used to be present appears to have been fixed, so the
workaround can be removed

* Minor changes

* Fix deprecated QCheckBox signal

* Fix setContent helper functions

* Remove QMultiMap usage from ControlLayout

* Remove SIGNAL and SLOT macros

* Revert TrackView.cpp changes

* Remove Q_DISABLE_MOVE usage since it does not seem to be available in Qt6

---------

Co-authored-by: michaelgregorius <michael.gregorius.git@arcor.de>
Co-authored-by: Rossmaxx <74815851+Rossmaxx@users.noreply.github.com>
Co-authored-by: BoredGuy1 <66702733+BoredGuy1@users.noreply.github.com>
Co-authored-by: Hyunjin Song <tteu.ingog@gmail.com>
Co-authored-by: Lisa Magdalena Riedler <git@riedler.wien>
Co-authored-by: Dalton Messmer <messmer.dalton@gmail.com>

.github/workflows/build.yml

@@ -372,10 +372,10 @@ jobs:
       - name: Install tools
         run: choco install ccache
       - name: Install Qt
-        uses: jurplel/install-qt-action@b3ea5275e37b734d027040e2c7fe7a10ea2ef946
+        uses: jurplel/install-qt-action@d325aaf2a8baeeda41ad0b5d39f84a6af9bcf005
         with:
-          version: '5.15.2'
-          arch: "win64_msvc2019_64"
+          version: '6.8.*'
+          arch: "win64_msvc2022_64"
           archives: qtbase qtsvg qttools
           cache: true
       - name: Set up build environment
@@ -392,6 +392,7 @@ jobs:
             --toolchain C:/vcpkg/scripts/buildsystems/vcpkg.cmake `
             -Werror=dev `
             -DCMAKE_BUILD_TYPE=RelWithDebInfo `
+            -DWANT_QT6=ON `
             -DUSE_COMPILE_CACHE=ON `
             -DUSE_WERROR=ON `
             -DVCPKG_TARGET_TRIPLET="x64-windows" `

CMakeLists.txt

@@ -107,6 +107,7 @@ option(WANT_DEBUG_GPROF	"Enable gprof profiler" OFF)
 OPTION(BUNDLE_QT_TRANSLATIONS	"Install Qt translation files for LMMS" OFF)
 option(WANT_DEBUG_CPACK "Show detailed logs for packaging commands" OFF)
 option(WANT_CPACK_TARBALL "Request CPack to create a tarball instead of an installer" OFF)
+option(WANT_QT6 "Build with experimental Qt6 support" OFF)
 
 
 IF(LMMS_BUILD_APPLE)
@@ -174,31 +175,45 @@ check_library_exists(rt shm_open "" LMMS_HAVE_LIBRT)
 
 LIST(APPEND CMAKE_PREFIX_PATH "${CMAKE_INSTALL_PREFIX}")
 
-FIND_PACKAGE(Qt5 5.9.0 COMPONENTS Core Gui Widgets Xml Svg REQUIRED)
-FIND_PACKAGE(Qt5 COMPONENTS LinguistTools QUIET)
+if(WANT_QT6)
+	set(QT_VERSION_MAJOR 6)
+	if(MSVC)
+		set(LMMS_QT_MIN_VERSION 6.8.0)
+	else()
+		set(LMMS_QT_MIN_VERSION 6.0.0)
+	endif()
+	set(STATUS_QT6 "Enabled")
+else()
+	set(QT_VERSION_MAJOR 5)
+	set(LMMS_QT_MIN_VERSION 5.9.0)
+	set(STATUS_QT6 "Disabled")
+endif()
+
+find_package(Qt${QT_VERSION_MAJOR} ${LMMS_QT_MIN_VERSION} COMPONENTS Core Gui Widgets Xml Svg REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} COMPONENTS LinguistTools QUIET)
 
 include_directories(SYSTEM
-	${Qt5Core_INCLUDE_DIRS}
-	${Qt5Gui_INCLUDE_DIRS}
-	${Qt5Widgets_INCLUDE_DIRS}
-	${Qt5Xml_INCLUDE_DIRS}
+	${Qt${QT_VERSION_MAJOR}Core_INCLUDE_DIRS}
+	${Qt${QT_VERSION_MAJOR}Gui_INCLUDE_DIRS}
+	${Qt${QT_VERSION_MAJOR}Widgets_INCLUDE_DIRS}
+	${Qt${QT_VERSION_MAJOR}Xml_INCLUDE_DIRS}
 )
 
-SET(QT_LIBRARIES
-	Qt5::Core
-	Qt5::Gui
-	Qt5::Widgets
-	Qt5::Xml
-	Qt5::Svg
+set(QT_LIBRARIES
+	Qt${QT_VERSION_MAJOR}::Core
+	Qt${QT_VERSION_MAJOR}::Gui
+	Qt${QT_VERSION_MAJOR}::Widgets
+	Qt${QT_VERSION_MAJOR}::Xml
+	Qt${QT_VERSION_MAJOR}::Svg
 )
 
-IF(LMMS_BUILD_LINUX AND WANT_VST)
+IF(LMMS_BUILD_LINUX AND WANT_VST AND NOT WANT_QT6)
     FIND_PACKAGE(Qt5 COMPONENTS X11Extras REQUIRED)
     LIST(APPEND QT_LIBRARIES Qt5::X11Extras)
 ENDIF()
 
-# Resolve Qt5::qmake to full path for use in packaging scripts
-GET_TARGET_PROPERTY(QT_QMAKE_EXECUTABLE "${Qt5Core_QMAKE_EXECUTABLE}" IMPORTED_LOCATION)
+# Resolve qmake to full path for use in packaging scripts
+get_target_property(QT_QMAKE_EXECUTABLE Qt${QT_VERSION_MAJOR}::qmake IMPORTED_LOCATION)
 
 # Find the location of Qt translation files
 execute_process(COMMAND ${QT_QMAKE_EXECUTABLE} -query QT_INSTALL_TRANSLATIONS
@@ -211,8 +226,8 @@ IF(EXISTS "${QT_TRANSLATIONS_DIR}")
 	ADD_DEFINITIONS("-DQT_TRANSLATIONS_DIR=\"${QT_TRANSLATIONS_DIR}\"")
 ENDIF()
 
-FIND_PACKAGE(Qt5Test)
-SET(QT_QTTEST_LIBRARY Qt5::Test)
+FIND_PACKAGE(Qt${QT_VERSION_MAJOR}Test)
+SET(QT_QTTEST_LIBRARY Qt${QT_VERSION_MAJOR}::Test)
 
 # check for libsndfile
 FIND_PACKAGE(SndFile REQUIRED)
@@ -878,6 +893,7 @@ MESSAGE(
 "* Debug packaging commands          : ${STATUS_DEBUG_CPACK}\n"
 "* Profile using GNU profiler        : ${STATUS_GPROF}\n"
 "* Debug assertions                  : ${STATUS_ASSERTIONS}\n"
+"* Experimental Qt6 support          : ${STATUS_QT6}\n"
 )
 
 MESSAGE(

cmake/install/CMakeLists.txt

@@ -1,9 +1,9 @@
 SET(PLUGIN_FILES "")
 IF(LMMS_BUILD_WIN32)
-        INSTALL(FILES $<TARGET_FILE:Qt5::QWindowsIntegrationPlugin> DESTINATION platforms)
-        INSTALL(FILES $<TARGET_FILE:Qt5::QSvgIconPlugin> DESTINATION iconengines)
-        INSTALL(FILES $<TARGET_FILE:Qt5::QSvgPlugin> DESTINATION imageformats)
-        INSTALL(FILES $<TARGET_FILE:Qt5::Svg> DESTINATION .)
+        INSTALL(FILES $<TARGET_FILE:Qt${QT_VERSION_MAJOR}::QWindowsIntegrationPlugin> DESTINATION platforms)
+        INSTALL(FILES $<TARGET_FILE:Qt${QT_VERSION_MAJOR}::QSvgIconPlugin> DESTINATION iconengines)
+        INSTALL(FILES $<TARGET_FILE:Qt${QT_VERSION_MAJOR}::QSvgPlugin> DESTINATION imageformats)
+        INSTALL(FILES $<TARGET_FILE:Qt${QT_VERSION_MAJOR}::Svg> DESTINATION .)
 ENDIF()
 
 IF(LMMS_BUILD_WIN32 OR LMMS_INSTALL_DEPENDENCIES)

cmake/linux/LinuxDeploy.cmake

@@ -128,6 +128,10 @@ set(ENV{PATH} "${QTBIN}:$ENV{PATH}")
 # Promote finding our own libraries first
 set(ENV{LD_LIBRARY_PATH} "${APP}/usr/lib/${lmms}/:${APP}/usr/lib/${lmms}/optional:$ENV{LD_LIBRARY_PATH}")
 
+# Workaround for finding libs from online installer
+# https://github.com/linuxdeploy/linuxdeploy-plugin-qt/issues/193
+set(ENV{LD_LIBRARY_PATH} "${QTBIN}/../lib:$ENV{LD_LIBRARY_PATH}")
+
 # Skip slow searching of copyright files https://github.com/linuxdeploy/linuxdeploy/issues/278
 set(ENV{DISABLE_COPYRIGHT_FILES_DEPLOYMENT} 1)
 

cmake/modules/BuildPlugin.cmake

@@ -30,7 +30,7 @@ MACRO(BUILD_PLUGIN PLUGIN_NAME)
 		ADD_GEN_QRC(RCC_OUT "${PLUGIN_NAME}.qrc" PREFIX artwork/${PLUGIN_NAME} ${PLUGIN_EMBEDDED_RESOURCES})
 	ENDIF(ER_LEN)
 
-	QT5_WRAP_CPP(plugin_MOC_out ${PLUGIN_MOCFILES})
+	cmake_language(CALL QT${QT_VERSION_MAJOR}_WRAP_CPP plugin_MOC_out ${PLUGIN_MOCFILES})
 
 	FOREACH(f ${PLUGIN_SOURCES})
 		ADD_FILE_DEPENDENCIES(${f} ${RCC_OUT})
@@ -51,7 +51,7 @@ MACRO(BUILD_PLUGIN PLUGIN_NAME)
 
 	ADD_LIBRARY(${PLUGIN_NAME} ${PLUGIN_LINK} ${PLUGIN_SOURCES} ${plugin_MOC_out} ${RCC_OUT})
 
-	target_link_libraries("${PLUGIN_NAME}" lmms Qt5::Widgets Qt5::Xml)
+	target_link_libraries("${PLUGIN_NAME}" lmms Qt${QT_VERSION_MAJOR}::Widgets Qt${QT_VERSION_MAJOR}::Xml)
 
 	INSTALL(TARGETS ${PLUGIN_NAME}
 		LIBRARY DESTINATION "${PLUGIN_DIR}"

cmake/modules/GenQrc.cmake

@@ -58,7 +58,7 @@ function(add_gen_qrc RCC_OUT QRC_NAME)
 	# generators. See issue #6177.
 	add_custom_command(
 		OUTPUT "${CPP_FILE}"
-		COMMAND Qt5::rcc
+		COMMAND Qt${QT_VERSION_MAJOR}::rcc
 			--name "${RESOURCE_NAME}"
 			--output "${CPP_FILE}"
 			"${QRC_FILE}"

data/locale/CMakeLists.txt

@@ -1,5 +1,5 @@
-SET(QT_LUPDATE_EXECUTABLE "${Qt5_LUPDATE_EXECUTABLE}")
-SET(QT_LRELEASE_EXECUTABLE "${Qt5_LRELEASE_EXECUTABLE}")
+SET(QT_LUPDATE_EXECUTABLE "${Qt${QT_VERSION_MAJOR}_LUPDATE_EXECUTABLE}")
+SET(QT_LRELEASE_EXECUTABLE "${Qt${QT_VERSION_MAJOR}_LRELEASE_EXECUTABLE}")
 
 IF(QT_LUPDATE_EXECUTABLE STREQUAL "")
 	EXECUTE_PROCESS(COMMAND "lupdate" "-help" RESULT_VARIABLE LUPDATE_FALLBACK OUTPUT_QUIET)

include/ColorChooser.h

@@ -55,8 +55,7 @@ protected:
 	//! Forward key events to the parent to prevent stuck notes when the dialog gets focus
 	void keyReleaseEvent(QKeyEvent *event) override
 	{
-		QKeyEvent ke(*event);
-		QApplication::sendEvent(parentWidget(), &ke);
+		QApplication::sendEvent(parentWidget(), event);
 	}
 private:
 	//! Copy the current QColorDialog palette into an array

include/ColorHelper.h

@@ -35,17 +35,23 @@ class ColorHelper
 public:
 	static QColor interpolateInRgb(const QColor& a, const QColor& b, float t)
 	{
-		qreal ar, ag, ab, aa;
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+		using ColorType = float;
+#else
+		using ColorType = qreal;
+#endif
+
+		ColorType ar, ag, ab, aa;
 		a.getRgbF(&ar, &ag, &ab, &aa);
 
-		qreal br, bg, bb, ba;
+		ColorType br, bg, bb, ba;
 		b.getRgbF(&br, &bg, &bb, &ba);
 
-		const auto t2 = static_cast<qreal>(t);
-		const float interH = std::lerp(ar, br, t2);
-		const float interS = std::lerp(ag, bg, t2);
-		const float interV = std::lerp(ab, bb, t2);
-		const float interA = std::lerp(aa, ba, t2);
+		const auto t2 = static_cast<ColorType>(t);
+		const auto interH = std::lerp(ar, br, t2);
+		const auto interS = std::lerp(ag, bg, t2);
+		const auto interV = std::lerp(ab, bb, t2);
+		const auto interA = std::lerp(aa, ba, t2);
 
 		return QColor::fromRgbF(interH, interS, interV, interA);
 	}

include/ControlLayout.h

@@ -96,6 +96,8 @@ class ControlLayout : public QLayout
 {
 	Q_OBJECT
 
+	using ControlLayoutMap = QMap<QString, QLayoutItem*>;
+
 public:
 	explicit ControlLayout(QWidget *parent,
 		int margin = -1, int hSpacing = -1, int vSpacing = -1);
@@ -124,9 +126,9 @@ private slots:
 private:
 	int doLayout(const QRect &rect, bool testOnly) const;
 	int smartSpacing(QStyle::PixelMetric pm) const;
-	QMap<QString, QLayoutItem *>::const_iterator pairAt(int index) const;
+	ControlLayoutMap::const_iterator pairAt(int index) const;
 
-	QMultiMap<QString, QLayoutItem *> m_itemMap;
+	ControlLayoutMap m_itemMap;
 	int m_hSpace;
 	int m_vSpace;
 	// relevant dimension is width, as later, heightForWidth() will be called

include/DeprecationHelper.h

@@ -29,8 +29,10 @@
 
 #include <type_traits>
 
+#include <QDomDocument>
 #include <QFontMetrics>
 #include <QKeySequence>
+#include <QVariant>
 #include <QWheelEvent>
 
 namespace lmms
@@ -58,15 +60,74 @@ inline int horizontalAdvance(const QFontMetrics& metrics, const QString& text)
  * @param wheelEvent
  * @return the position of wheelEvent
  */
-inline QPoint position(QWheelEvent *wheelEvent)
+inline QPoint position(const QWheelEvent* wheelEvent)
 {
-#if (QT_VERSION >= QT_VERSION_CHECK(5, 15, 0))
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 14, 0))
 	return wheelEvent->position().toPoint();
 #else
 	return wheelEvent->pos();
 #endif
 }
 
+/**
+ * @brief position is a backwards-compatible adapter for
+ * QDropEvent::position and pos functions.
+ * @param me
+ * @return the position of the drop event
+ */
+inline QPoint position(const QDropEvent* de)
+{
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+	return de->position().toPoint();
+#else
+	return de->pos();
+#endif
+}
+
+/**
+ * @brief position is a backwards-compatible adapter for
+ * QMouseEvent::position and pos functions.
+ * @param me
+ * @return the position of the mouse event
+ */
+inline QPoint position(const QMouseEvent* me)
+{
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+	return me->position().toPoint();
+#else
+	return me->pos();
+#endif
+}
+
+/**
+ * @brief positionF is a backwards-compatible adapter for
+ * QMouseEvent::position and localPos functions.
+ * @param me
+ * @return the position of the mouse event
+ */
+inline QPointF positionF(const QMouseEvent* me)
+{
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+	return me->position();
+#else
+	return me->localPos();
+#endif
+}
+
+/**
+ * @brief globalPosition is a backwards-compatible adapter for
+ * QMouseEvent::globalPosition and globalPos functions.
+ * @param me
+ * @return the global position of the mouse event
+ */
+inline QPoint globalPosition(const QMouseEvent* me)
+{
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+	return me->globalPosition().toPoint();
+#else
+	return me->globalPos();
+#endif
+}
 
 namespace detail
 {
@@ -77,20 +138,69 @@ inline constexpr bool IsKeyOrModifier = std::is_same_v<T, Qt::Key>
 
 } // namespace detail
 
-
 /**
  * @brief Combines Qt key and modifier arguments together,
  * replacing `A | B` which was deprecated in C++20
  * due to the enums being different types. (P1120R0)
  * @param args Any number of Qt::Key, Qt::Modifier, or Qt::KeyboardModifier
- * @return The combination of the given keys/modifiers as an int
+ * @return The combination of the given keys/modifiers as a QKeySequence
  */
-template<typename... Args, std::enable_if_t<(detail::IsKeyOrModifier<Args> && ...), bool> = true>
-constexpr int combine(Args... args)
+template<typename... Args> requires (detail::IsKeyOrModifier<Args> && ...)
+inline QKeySequence keySequence(Args... args)
 {
 	return (0 | ... | static_cast<int>(args));
 }
 
+/**
+ * @brief typeId is a backwards-compatible adapter for
+ * QVariant::typeId and type functions.
+ * @param variant
+ * @return the type id of the variant
+ */
+inline QMetaType::Type typeId(const QVariant& variant)
+{
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+	return static_cast<QMetaType::Type>(variant.typeId());
+#else
+	return static_cast<QMetaType::Type>(variant.type());
+#endif
+}
+
+//! Backwards-compatible adapter for QDomDocument::setContent
+inline bool setContent(QDomDocument& doc, const QByteArray& text,
+	QString* errorMsg = nullptr, int* errorLine = nullptr, int* errorColumn = nullptr)
+{
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 5, 0))
+	auto result = doc.setContent(text, QDomDocument::ParseOption::Default);
+	if (result) { return true; }
+	if (errorMsg) { *errorMsg = std::move(result.errorMessage); }
+	if (errorLine) { *errorLine = static_cast<int>(result.errorLine); }
+	if (errorColumn) { *errorColumn = static_cast<int>(result.errorColumn); }
+	return false;
+#else
+	return doc.setContent(text, errorMsg, errorLine, errorColumn);
+#endif
+}
+
+//! Backwards-compatible adapter for QDomDocument::setContent
+inline bool setContent(QDomDocument& doc, QIODevice* dev, bool namespaceProcessing,
+	QString* errorMsg = nullptr, int* errorLine = nullptr, int* errorColumn = nullptr)
+{
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 5, 0))
+	const auto options = namespaceProcessing
+		? QDomDocument::ParseOption::UseNamespaceProcessing
+		: QDomDocument::ParseOption::Default;
+	auto result = doc.setContent(dev, options);
+	if (result) { return true; }
+	if (errorMsg) { *errorMsg = std::move(result.errorMessage); }
+	if (errorLine) { *errorLine = static_cast<int>(result.errorLine); }
+	if (errorColumn) { *errorColumn = static_cast<int>(result.errorColumn); }
+	return false;
+#else
+	return doc.setContent(dev, namespaceProcessing, errorMsg, errorLine, errorColumn);
+#endif
+}
+
 } // namespace lmms
 
 #endif // LMMS_DEPRECATIONHELPER_H

include/FileRevealer.h

@@ -48,6 +48,11 @@ public:
 	 */
 	static void openDir(const QFileInfo item);
 
+	static void openDir(const QString& itemPath)
+	{
+		openDir(QFileInfo(itemPath));
+	}
+
 	/**
 	 * @brief Checks whether the file manager supports selecting a specific file.
 	 * @return True if selection is supported, otherwise false.
@@ -60,6 +65,11 @@ public:
 	 */
 	static void reveal(const QFileInfo item);
 
+	static void reveal(const QString& itemPath)
+	{
+		reveal(QFileInfo(itemPath));
+	}
+
 private:
 	static bool s_canSelect;
 

include/FileSearchJob.h

@@ -52,6 +52,11 @@ public:
 	//! Stop processing and destroys the object.
 	~FileSearchJob();
 
+	FileSearchJob(const FileSearchJob&) = delete;
+	FileSearchJob(FileSearchJob&&) = delete;
+	FileSearchJob& operator=(const FileSearchJob&) = delete;
+	FileSearchJob& operator=(FileSearchJob&&) = delete;
+
 	//! Commit to searching with the given @p task.
 	//! Cancels any previous search.
 	//! Callers can connect to the provided signals to interact with the search and its progress.
@@ -68,7 +73,6 @@ signals:
 	void finished();
 
 private:
-	Q_DISABLE_MOVE(FileSearchJob)
 	void runSearch(Task task);
 	std::future<void> m_task;
 	std::atomic_flag m_stop = ATOMIC_FLAG_INIT;

include/FloatModelEditorBase.h

@@ -81,7 +81,11 @@ protected:
 	void paintEvent(QPaintEvent * me) override;
 	void wheelEvent(QWheelEvent * me) override;
 
-	void enterEvent(QEvent *event) override;
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+	void enterEvent(QEnterEvent*) override;
+#else
+	void enterEvent(QEvent*) override;
+#endif
 	void leaveEvent(QEvent *event) override;
 
 	virtual float getValue(const QPoint & p);

include/MainApplication.h

@@ -49,10 +49,14 @@ public:
 	MainApplication(int& argc, char** argv);
 	bool event(QEvent* event) override;
 #ifdef LMMS_BUILD_WIN32
-	bool winEventFilter(MSG* msg, long* result);
-	bool nativeEventFilter(const QByteArray& eventType, void* message,
-				long* result);
-#endif
+#if (QT_VERSION < QT_VERSION_CHECK(6,0,0))
+	using FilterResult = long;
+#else
+	using FilterResult = qintptr;
+#endif // QT6 check
+	bool win32EventFilter(MSG* msg, FilterResult* result);
+	bool nativeEventFilter(const QByteArray& eventType, void* message, FilterResult* result);
+#endif // LMMS_BUILD_WIN32
 	inline QString& queuedFile()
 	{
 	    return m_queuedFile;

include/PluginBrowser.h

@@ -65,7 +65,11 @@ public:
 	void openInNewInstrumentTrack(QString value);
 
 protected:
-	void enterEvent( QEvent * _e ) override;
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+	void enterEvent(QEnterEvent* event) override;
+#else
+	void enterEvent(QEvent* event) override;
+#endif
 	void leaveEvent( QEvent * _e ) override;
 	void mousePressEvent( QMouseEvent * _me ) override;
 	void paintEvent( QPaintEvent * _pe ) override;

include/TabWidget.h

@@ -48,7 +48,7 @@ public:
 
 	void setActiveTab(int idx);
 
-	int findTabAtPos(const QPoint* pos);
+	int findTabAtPos(const QPoint& pos);
 
 	inline int activeTab() const
 	{

include/base64.h

@@ -27,6 +27,7 @@
 #define LMMS_BASE64_H
 
 #include <QByteArray>
+#include <QMetaType>
 #include <QString>
 #include <QVariant>
 
@@ -47,9 +48,10 @@ namespace lmms::base64
 		*_data = new T[*_size / sizeof(T)];
 		memcpy( *_data, data.constData(), *_size );
 	}
+
 	// for compatibility-code only
-	QVariant decode( const QString & _b64,
-			QVariant::Type _force_type = QVariant::Invalid );
+	QVariant decode(const QString& b64,
+		QMetaType::Type forceType = QMetaType::UnknownType);
 
 } // namespace lmms::base64
 

include/embed.h

@@ -58,16 +58,12 @@ auto LMMS_EXPORT getText(std::string_view name) -> QString;
  * @param pixmap The pixmap to get the size of.
  * @return The device-independent size of the pixmap.
  */
-#if QT_VERSION >= QT_VERSION_CHECK(6, 2, 0)
-[[deprecated("Use QPixmap::deviceIndependentSize() instead; See "
-             "https://doc.qt.io/qt-6/qpixmap.html#deviceIndependentSize")]]
-#endif
-inline auto logicalSize(const QPixmap &pixmap) noexcept
+inline auto logicalSize(const QPixmap& pixmap) noexcept
 {
 #if QT_VERSION >= QT_VERSION_CHECK(6, 2, 0)
 	return pixmap.deviceIndependentSize().toSize();
 #else
-	return pixmap.isNull() ? QSize() : pixmap.size() / pixmap.devicePixelRatio();
+	return pixmap.isNull() ? QSize(0, 0) : pixmap.size() / pixmap.devicePixelRatio();
 #endif
 }
 

plugins/AudioFileProcessor/AudioFileProcessorWaveView.cpp

@@ -26,9 +26,11 @@
 
 #include "Sample.h"
 #include "ConfigManager.h"
+#include "DeprecationHelper.h"
 #include "SampleThumbnail.h"
 #include "FontHelper.h"
 
+
 #include <QPainter>
 #include <QMouseEvent>
 
@@ -114,10 +116,12 @@ void AudioFileProcessorWaveView::leaveEvent(QEvent * e)
 
 void AudioFileProcessorWaveView::mousePressEvent(QMouseEvent * me)
 {
-	m_isDragging = true;
-	m_draggingLastPoint = me->pos();
+	const auto pos = position(me);
 
-	const int x = me->x();
+	m_isDragging = true;
+	m_draggingLastPoint = pos;
+
+	const int x = pos.x();
 
 	const int start_dist =		qAbs(m_startFrameX - x);
 	const int end_dist = 		qAbs(m_endFrameX - x);
@@ -155,7 +159,9 @@ void AudioFileProcessorWaveView::mouseMoveEvent(QMouseEvent * me)
 		return;
 	}
 
-	const int step = me->x() - m_draggingLastPoint.x();
+	const auto pos = position(me);
+
+	const int step = pos.x() - m_draggingLastPoint.x();
 	switch(m_draggingType)
 	{
 		case DraggingType::SampleStart:
@@ -171,12 +177,12 @@ void AudioFileProcessorWaveView::mouseMoveEvent(QMouseEvent * me)
 			slide(step);
 			break;
 		case DraggingType::ZoomWave:
-			zoom(me->y() < m_draggingLastPoint.y());
+			zoom(pos.y() < m_draggingLastPoint.y());
 			break;
 		case DraggingType::Wave:
 		default:
-			if (qAbs(me->y() - m_draggingLastPoint.y())
-				< 2 * qAbs(me->x() - m_draggingLastPoint.x()))
+			if (qAbs(pos.y() - m_draggingLastPoint.y())
+				< 2 * qAbs(pos.x() - m_draggingLastPoint.x()))
 			{
 				m_draggingType = DraggingType::SlideWave;
 			}
@@ -186,7 +192,7 @@ void AudioFileProcessorWaveView::mouseMoveEvent(QMouseEvent * me)
 			}
 	}
 
-	m_draggingLastPoint = me->pos();
+	m_draggingLastPoint = pos;
 	update();
 }
 
@@ -483,20 +489,30 @@ void AudioFileProcessorWaveView::reverse()
 	m_reversed = ! m_reversed;
 }
 
-void AudioFileProcessorWaveView::updateCursor(QMouseEvent * me)
+void AudioFileProcessorWaveView::updateCursor(const QMouseEvent* me)
 {
 	bool const waveIsDragged = m_isDragging && (m_draggingType == DraggingType::Wave);
-	bool const pointerCloseToStartEndOrLoop = (me != nullptr) &&
-			(isCloseTo(me->x(), m_startFrameX) ||
-			  isCloseTo(me->x(), m_endFrameX) ||
-			  isCloseTo(me->x(), m_loopFrameX));
 
-	if (!m_isDragging && pointerCloseToStartEndOrLoop)
+	if (!m_isDragging && pointerCloseToStartEndOrLoop(me))
+	{
 		setCursor(Qt::SizeHorCursor);
+	}
 	else if (waveIsDragged)
+	{
 		setCursor(Qt::ClosedHandCursor);
+	}
 	else
+	{
 		setCursor(Qt::OpenHandCursor);
+	}
+}
+
+bool AudioFileProcessorWaveView::pointerCloseToStartEndOrLoop(const QMouseEvent* me) const
+{
+	if (!me) { return false; }
+
+	const QPoint pos = position(me);
+	return isCloseTo(pos.x(), m_startFrameX) || isCloseTo(pos.x(), m_endFrameX) || isCloseTo(pos.x(), m_loopFrameX);
 }
 
 void AudioFileProcessorWaveView::configureKnobRelationsAndWaveViews()

plugins/AudioFileProcessor/AudioFileProcessorWaveView.h

@@ -169,7 +169,8 @@ private:
 
 	void updateGraph();
 	void reverse();
-	void updateCursor(QMouseEvent* me = nullptr);
+	void updateCursor(const QMouseEvent* me = nullptr);
+	bool pointerCloseToStartEndOrLoop(const QMouseEvent* me) const;
 
 	void configureKnobRelationsAndWaveViews();
 

plugins/Delay/DelayControlsDialog.cpp

@@ -25,6 +25,7 @@
 #include "AutomatableModel.h"
 #include "DelayControlsDialog.h"
 #include "DelayControls.h"
+#include "DeprecationHelper.h"
 #include "embed.h"
 #include "TempoSyncKnob.h"
 #include "../Eq/EqFader.h"
@@ -135,18 +136,20 @@ void XyPad::mouseReleaseEvent(QMouseEvent *event)
 
 void XyPad::mouseMoveEvent(QMouseEvent *event)
 {
-	if( m_acceptInput && (event->x() >= 0) && ( event->x() < width() )
-			&& ( event->y() >= 0) && ( event->y() < height() ) )
+	const auto pos = position(event);
+
+	if (m_acceptInput && (pos.x() >= 0) && (pos.x() < width())
+		&& (pos.y() >= 0) && (pos.y() < height()))
 	{
 		//set xmodel
 		float xRange = m_xModel->maxValue() - m_xModel->minValue();
 		float xInc = xRange / width();
-		m_xModel->setValue( m_xModel->minValue() + ( event->x() * xInc ) );
+		m_xModel->setValue(m_xModel->minValue() + (pos.x() * xInc));
 
 		//set ymodel
 		float yRange = m_yModel->maxValue() - m_yModel->minValue();
 		float yInc = yRange / height();
-		m_yModel->setValue( m_yModel->minValue() + ( event->y() * yInc ) );
+		m_yModel->setValue(m_yModel->minValue() + (pos.y() * yInc));
 	}
 }
 

plugins/LadspaEffect/LadspaMatrixControlDialog.cpp

@@ -178,7 +178,7 @@ QWidget * LadspaMatrixControlDialog::createMatrixWidget()
 {
 	QWidget *widget = new QWidget(this);
 	QGridLayout *gridLayout = new QGridLayout(widget);
-	gridLayout->setMargin(0);
+	gridLayout->setContentsMargins(0, 0, 0, 0);
 	widget->setLayout(gridLayout);
 
 	arrangeControls(widget, gridLayout);

plugins/OpulenZ/OpulenZ.cpp

@@ -590,7 +590,7 @@ void OpulenzInstrument::loadFile( const QString& file ) {
 			return;
 		}
 		if( sbidata.size() != 52 ) {
-			printf("SBI size error: expected 52, got %d\n",sbidata.size() );
+			printf("SBI size error: expected 52, got %d\n", static_cast<int>(sbidata.size()));
 		}
 
 		// Minimum size of SBI if we ignore "reserved" bytes at end

plugins/SlicerT/SlicerTWaveform.cpp

@@ -29,6 +29,7 @@
 #include <QPainter>
 #include <QPainterPath>
 
+#include "DeprecationHelper.h"
 #include "SampleThumbnail.h"
 #include "SlicerT.h"
 #include "SlicerTView.h"
@@ -297,13 +298,15 @@ void SlicerTWaveform::updateUI()
 // updates the closest object and changes the cursor respectivly
 void SlicerTWaveform::updateClosest(QMouseEvent* me)
 {
-	float normalizedClickSeeker = static_cast<float>(me->x() - s_seekerHorMargin) / m_seekerWidth;
-	float normalizedClickEditor = static_cast<float>(me->x()) / m_editorWidth;
+	const auto pos = position(me);
+
+	float normalizedClickSeeker = static_cast<float>(pos.x() - s_seekerHorMargin) / m_seekerWidth;
+	float normalizedClickEditor = static_cast<float>(pos.x()) / m_editorWidth;
 
 	m_closestObject = UIObjects::Nothing;
 	m_closestSlice = -1;
 
-	if (me->y() < m_seekerHeight)
+	if (pos.y() < m_seekerHeight)
 	{
 		if (std::abs(normalizedClickSeeker - m_seekerStart) < s_distanceForClick)
 		{
@@ -358,6 +361,8 @@ void SlicerTWaveform::updateCursor()
 // handles deletion, reset and middles seeker
 void SlicerTWaveform::mousePressEvent(QMouseEvent* me)
 {
+	const auto pos = position(me);
+
 	switch (me->button())
 	{
 	case Qt::MouseButton::MiddleButton:
@@ -369,7 +374,7 @@ void SlicerTWaveform::mousePressEvent(QMouseEvent* me)
 	case Qt::MouseButton::LeftButton:
 		if (m_slicerTParent->m_originalSample.sampleSize() <= 1) { static_cast<SlicerTView*>(parent())->openFiles(); }
 		// update seeker middle for correct movement
-		m_seekerMiddle = static_cast<float>(me->x() - s_seekerHorMargin) / m_seekerWidth;
+		m_seekerMiddle = static_cast<float>(pos.x() - s_seekerHorMargin) / m_seekerWidth;
 		break;
 	case Qt::MouseButton::RightButton:
 		if (m_slicerTParent->m_slicePoints.size() > 2 && m_closestObject == UIObjects::SlicePoint)
@@ -400,8 +405,10 @@ void SlicerTWaveform::mouseMoveEvent(QMouseEvent* me)
 		return;
 	}
 
-	float normalizedClickSeeker = static_cast<float>(me->x() - s_seekerHorMargin) / m_seekerWidth;
-	float normalizedClickEditor = static_cast<float>(me->x()) / m_editorWidth;
+	const auto pos = position(me);
+
+	float normalizedClickSeeker = static_cast<float>(pos.x() - s_seekerHorMargin) / m_seekerWidth;
+	float normalizedClickEditor = static_cast<float>(pos.x()) / m_editorWidth;
 
 	float distStart = m_seekerStart - m_seekerMiddle;
 	float distEnd = m_seekerEnd - m_seekerMiddle;
@@ -449,9 +456,11 @@ void SlicerTWaveform::mouseMoveEvent(QMouseEvent* me)
 
 void SlicerTWaveform::mouseDoubleClickEvent(QMouseEvent* me)
 {
-	if (me->button() != Qt::MouseButton::LeftButton || me->y() < m_seekerHeight) { return; }
+	const auto pos = position(me);
 
-	float normalizedClickEditor = static_cast<float>(me->x()) / m_editorWidth;
+	if (me->button() != Qt::MouseButton::LeftButton || pos.y() < m_seekerHeight) { return; }
+
+	float normalizedClickEditor = static_cast<float>(pos.x()) / m_editorWidth;
 	float startFrame = m_seekerStart;
 	float endFrame = m_seekerEnd;
 	float slicePosition = startFrame + normalizedClickEditor * (endFrame - startFrame);

plugins/SpectrumAnalyzer/SaSpectrumView.cpp

@@ -33,6 +33,7 @@
 #include <QPainterPath>
 #include <QString>
 
+#include "DeprecationHelper.h"
 #include "fft_helpers.h"
 #include "GuiApplication.h"
 #include "MainWindow.h"
@@ -819,18 +820,14 @@ void SaSpectrumView::periodicUpdate()
 
 
 // Handle mouse input: set new cursor position.
-// For some reason (a bug?), localPos() only returns integers. As a workaround
-// the fractional part is taken from windowPos() (which works correctly).
-void SaSpectrumView::mouseMoveEvent(QMouseEvent *event)
+void SaSpectrumView::mouseMoveEvent(QMouseEvent* event)
 {
-	m_cursor = QPointF(	event->localPos().x() - (event->windowPos().x() - (long)event->windowPos().x()),
-						event->localPos().y() - (event->windowPos().y() - (long)event->windowPos().y()));
+	m_cursor = positionF(event);
 }
 
-void SaSpectrumView::mousePressEvent(QMouseEvent *event)
+void SaSpectrumView::mousePressEvent(QMouseEvent* event)
 {
-	m_cursor = QPointF(	event->localPos().x() - (event->windowPos().x() - (long)event->windowPos().x()),
-						event->localPos().y() - (event->windowPos().y() - (long)event->windowPos().y()));
+	m_cursor = positionF(event);
 }
 
 

plugins/SpectrumAnalyzer/SaWaterfallView.cpp

@@ -33,6 +33,7 @@
 #include <QPainter>
 #include <QString>
 
+#include "DeprecationHelper.h"
 #include "EffectControlDialog.h"
 #include "GuiApplication.h"
 #include "MainWindow.h"
@@ -324,18 +325,14 @@ void SaWaterfallView::drawCursor(QPainter &painter)
 
 
 // Handle mouse input: set new cursor position.
-// For some reason (a bug?), localPos() only returns integers. As a workaround
-// the fractional part is taken from windowPos() (which works correctly).
-void SaWaterfallView::mouseMoveEvent(QMouseEvent *event)
+void SaWaterfallView::mouseMoveEvent(QMouseEvent* event)
 {
-	m_cursor = QPointF(	event->localPos().x() - (event->windowPos().x() - (long)event->windowPos().x()),
-						event->localPos().y() - (event->windowPos().y() - (long)event->windowPos().y()));
+	m_cursor = positionF(event);
 }
 
-void SaWaterfallView::mousePressEvent(QMouseEvent *event)
+void SaWaterfallView::mousePressEvent(QMouseEvent* event)
 {
-	m_cursor = QPointF(	event->localPos().x() - (event->windowPos().x() - (long)event->windowPos().x()),
-						event->localPos().y() - (event->windowPos().y() - (long)event->windowPos().y()));
+	m_cursor = positionF(event);
 }
 
 

plugins/VstBase/VstPlugin.cpp

@@ -34,7 +34,7 @@
 #include <QLocale>
 #include <QTemporaryFile>
 
-#ifdef LMMS_BUILD_LINUX
+#if defined(LMMS_BUILD_LINUX) && (QT_VERSION < QT_VERSION_CHECK(6,0,0))
 #	include <QX11Info>
 #	include <X11EmbedContainer.h>
 #endif
@@ -415,7 +415,7 @@ bool VstPlugin::processMessage( const message & _m )
 					(LONG_PTR) gui::getGUI()->mainWindow()->winId() );
 #endif
 
-#ifdef LMMS_BUILD_LINUX
+#if defined(LMMS_BUILD_LINUX) && (QT_VERSION < QT_VERSION_CHECK(6,0,0))
 			XSetTransientForHint( QX11Info::display(),
 					m_pluginWindowID,
 					gui::getGUI()->mainWindow()->winId() );
@@ -772,7 +772,7 @@ void VstPlugin::createUI( QWidget * parent )
 	} else
 #endif
 
-#ifdef LMMS_BUILD_LINUX
+#if defined(LMMS_BUILD_LINUX) && (QT_VERSION < QT_VERSION_CHECK(6,0,0))
 	if (m_embedMethod == "xembed" )
 	{
 		if (parent)

plugins/VstBase/vstbase/CMakeLists.txt

@@ -15,6 +15,6 @@ TARGET_INCLUDE_DIRECTORIES(vstbase
 	PUBLIC ../
 )
 
-IF(LMMS_BUILD_LINUX)
+IF(LMMS_BUILD_LINUX AND NOT WANT_QT6)
 	TARGET_LINK_LIBRARIES(vstbase qx11embedcontainer)
 ENDIF()

plugins/ZynAddSubFx/CMakeLists.txt

@@ -23,8 +23,13 @@ if(NOT MSVC AND (LMMS_HOST_X86 OR LMMS_HOST_X86_64))
 	ADD_DEFINITIONS(-DASM_F2I_YES)
 endif()
 
-# build ZynAddSubFX with full optimizations
-if(NOT MSVC)
+if(MSVC)
+	# enable updated C++ language standards, disable certain permissive behavior
+	set(CMAKE_CXX_FLAGS  "${CMAKE_CXX_FLAGS} /Zc:__cplusplus /permissive-")
+	# workaround _WIN32 vs WIN32 differences
+	add_compile_definitions(WIN32)
+else()
+	# build ZynAddSubFX with full optimizations, treat nonconformant code as warnings
 	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O2 -fpermissive")
 endif()
 
@@ -126,8 +131,8 @@ target_static_libraries(ZynAddSubFxCore PUBLIC
 target_link_libraries(ZynAddSubFxCore INTERFACE
 	${FFTW3F_LIBRARIES}
 	${QT_LIBRARIES}
-	Qt5::Widgets
-	Qt5::Xml
+	Qt${QT_VERSION_MAJOR}::Widgets
+	Qt${QT_VERSION_MAJOR}::Xml
 	Threads::Threads
 	ZLIB::ZLIB
 )
@@ -192,7 +197,7 @@ if(LMMS_HAVE_LIBRT)
 endif()
 
 # Support qt_version_tag in Qt 5.6
-TARGET_LINK_LIBRARIES(RemoteZynAddSubFx Qt5::Core)
+TARGET_LINK_LIBRARIES(RemoteZynAddSubFx Qt${QT_VERSION_MAJOR}::Core)
 
 # link Qt libraries when on win32
 IF(LMMS_BUILD_WIN32)

src/3rdparty/CMakeLists.txt

@@ -1,6 +1,6 @@
 set_directory_properties(PROPERTIES SYSTEM TRUE)
 
-if(LMMS_BUILD_LINUX AND LMMS_HAVE_VST)
+if(LMMS_BUILD_LINUX AND LMMS_HAVE_VST AND NOT WANT_QT6)
 	set(BUILD_SHARED_LIBS OFF)
 	add_subdirectory(qt5-x11embed)
 ENDIF()

src/CMakeLists.txt

@@ -35,6 +35,12 @@ ADD_SUBDIRECTORY(tracks)
 
 LIST(APPEND LMMS_SRCS ${LMMS_COMMON_SRCS})
 
+IF(WANT_QT6)
+	QT6_WRAP_UI(LMMS_UI_OUT ${LMMS_UIS})
+ELSE()
+	QT5_WRAP_UI(LMMS_UI_OUT ${LMMS_UIS})
+ENDIF()
+
 INCLUDE_DIRECTORIES(
 	"${CMAKE_CURRENT_BINARY_DIR}"
 	"${CMAKE_BINARY_DIR}"
@@ -114,6 +120,11 @@ TARGET_INCLUDE_DIRECTORIES(lmms
 )
 target_static_libraries(lmms PUBLIC lmmsobjs)
 
+# Enable updated C++ language standards
+IF(MSVC)
+	TARGET_COMPILE_OPTIONS(lmmsobjs PUBLIC "/Zc:__cplusplus" "/permissive-")
+ENDIF()
+
 # CMake doesn't define target_EXPORTS for OBJECT libraries.
 # See the documentation of DEFINE_SYMBOL for details.
 # Also add LMMS_STATIC_DEFINE for targets linking against it.

src/core/AutomationClip.cpp

@@ -186,7 +186,7 @@ TimePos AutomationClip::timeMapLength() const
 	if (m_timeMap.isEmpty()) { return one_bar; }
 
 	timeMap::const_iterator it = m_timeMap.end();
-	auto last_tick = static_cast<tick_t>(POS(it - 1));
+	auto last_tick = static_cast<tick_t>(POS(std::prev(it)));
 	// if last_tick is 0 (single item at tick 0)
 	// return length as a whole bar to prevent disappearing Clip
 	if (last_tick == 0) { return one_bar; }
@@ -582,13 +582,16 @@ float AutomationClip::valueAt( const TimePos & _time ) const
 	{
 		return 0;
 	}
+
+	const auto pv = std::prev(v);
+
 	if( v == m_timeMap.end() )
 	{
 		// When the time is after the last node, we want the outValue of it
-		return OUTVAL(v - 1);
+		return OUTVAL(pv);
 	}
 
-	return valueAt(v - 1, _time - POS(v - 1));
+	return valueAt(pv, _time - POS(pv));
 }
 
 
@@ -610,9 +613,10 @@ float AutomationClip::valueAt( timeMap::const_iterator v, int offset ) const
 	}
 	else if( m_progressionType == ProgressionType::Linear )
 	{
+		auto const nv = std::next(v);
 		float slope =
-			(INVAL(v + 1) - OUTVAL(v))
-			/ (POS(v + 1) - POS(v));
+			(INVAL(nv) - OUTVAL(v))
+			/ (POS(nv) - POS(v));
 
 		return OUTVAL(v) + offset * slope;
 	}
@@ -626,15 +630,17 @@ float AutomationClip::valueAt( timeMap::const_iterator v, int offset ) const
 		// value: y.  To make this work we map the values of x that this
 		// segment spans to values of t for t = 0.0 -> 1.0 and scale the
 		// tangents _m1 and _m2
-		int numValues = (POS(v + 1) - POS(v));
+		auto const nv = std::next(v);
+
+		int numValues = (POS(nv) - POS(v));
 		float t = (float) offset / (float) numValues;
 		float m1 = OUTTAN(v) * numValues * m_tension;
-		float m2 = INTAN(v + 1) * numValues * m_tension;
+		float m2 = INTAN(nv) * numValues * m_tension;
 
 		auto t2 = t * t, t3 = t2 * t;
 		return (2 * t3 - 3 * t2 + 1) * OUTVAL(v)
 			+ (t3 - 2 * t2 + t) * m1
-			+ (-2 * t3 + 3 * t2) * INVAL(v + 1)
+			+ (-2 * t3 + 3 * t2) * INVAL(nv)
 			+ (t3 - t2) * m2;
 	}
 }
@@ -647,12 +653,14 @@ float *AutomationClip::valuesAfter( const TimePos & _time ) const
 	QMutexLocker m(&m_clipMutex);
 
 	timeMap::const_iterator v = m_timeMap.lowerBound(_time);
-	if( v == m_timeMap.end() || (v+1) == m_timeMap.end() )
+	auto const nv = std::next(v);
+
+	if (v == m_timeMap.end() || nv == m_timeMap.end())
 	{
 		return nullptr;
 	}
 
-	int numValues = POS(v + 1) - POS(v);
+	int numValues = POS(nv) - POS(v);
 	auto ret = new float[numValues];
 
 	for( int i = 0; i < numValues; i++ )
@@ -1156,7 +1164,9 @@ void AutomationClip::generateTangents(timeMap::iterator it, int numToGenerate)
 			continue;
 		}
 
-		if (it + 1 == m_timeMap.end())
+		auto const nit = std::next(it);
+
+		if (nit == m_timeMap.end())
 		{
 			// Previously, the last value's tangent was always set to 0. That logic was kept for both tangents
 			// of the last node
@@ -1167,7 +1177,7 @@ void AutomationClip::generateTangents(timeMap::iterator it, int numToGenerate)
 		{
 			// On the first node there's no curve behind it, so we will only calculate the outTangent
 			// and inTangent will be set to 0.
-			float tangent = (INVAL(it + 1) - OUTVAL(it)) / (POS(it + 1) - POS(it));
+			float tangent = (INVAL(nit) - OUTVAL(it)) / (POS(nit) - POS(it));
 			it.value().setInTangent(0);
 			it.value().setOutTangent(tangent);
 		}
@@ -1180,9 +1190,12 @@ void AutomationClip::generateTangents(timeMap::iterator it, int numToGenerate)
 			// TODO: This behavior means that a very small difference between the inValue and outValue can
 			// result in a big change in the curve. In the future, allowing the user to manually adjust
 			// the tangents would be better.
+
+			auto const pit = std::prev(it);
+
 			if (OFFSET(it) == 0)
 			{
-				float inTangent = (INVAL(it + 1) - OUTVAL(it - 1)) / (POS(it + 1) - POS(it - 1));
+				float inTangent = (INVAL(nit) - OUTVAL(pit)) / (POS(nit) - POS(pit));
 				it.value().setInTangent(inTangent);
 				// inTangent == outTangent in this case
 				it.value().setOutTangent(inTangent);
@@ -1190,9 +1203,9 @@ void AutomationClip::generateTangents(timeMap::iterator it, int numToGenerate)
 			else
 			{
 				// Calculate the left side of the curve
-				float inTangent = (INVAL(it) - OUTVAL(it - 1)) / (POS(it) - POS(it - 1));
+				float inTangent = (INVAL(it) - OUTVAL(pit)) / (POS(it) - POS(pit));
 				// Calculate the right side of the curve
-				float outTangent = (INVAL(it + 1) - OUTVAL(it)) / (POS(it + 1) - POS(it));
+				float outTangent = (INVAL(nit) - OUTVAL(it)) / (POS(nit) - POS(it));
 				it.value().setInTangent(inTangent);
 				it.value().setOutTangent(outTangent);
 			}

src/core/ConfigManager.cpp

@@ -24,7 +24,6 @@
 
 #include "ConfigManager.h"
 
-#include <PathUtil.h>
 #include <QApplication>
 #include <QDir>
 #include <QDomElement>
@@ -32,8 +31,10 @@
 #include <QStandardPaths>
 #include <QTextStream>
 
+#include "DeprecationHelper.h"
 #include "GuiApplication.h"
 #include "MainWindow.h"
+#include "PathUtil.h"
 #include "ProjectVersion.h"
 #include "lmmsversion.h"
 
@@ -202,7 +203,7 @@ QStringList ConfigManager::availableVstEmbedMethods()
 #ifdef LMMS_BUILD_WIN32
 	methods.append("win32");
 #endif
-#ifdef LMMS_BUILD_LINUX
+#if defined(LMMS_BUILD_LINUX) && (QT_VERSION < QT_VERSION_CHECK(6,0,0))
 	if (static_cast<QGuiApplication*>(QApplication::instance())->
 		platformName() == "xcb")
 	{
@@ -429,7 +430,7 @@ void ConfigManager::loadConfigFile(const QString & configFile)
 	{
 		QString errorString;
 		int errorLine, errorCol;
-		if(dom_tree.setContent(&cfg_file, false, &errorString, &errorLine, &errorCol))
+		if (lmms::setContent(dom_tree, &cfg_file, false, &errorString, &errorLine, &errorCol))
 		{
 			// get the head information from the DOM
 			QDomElement root = dom_tree.documentElement();

src/core/DataFile.cpp

@@ -40,6 +40,7 @@
 
 #include "base64.h"
 #include "ConfigManager.h"
+#include "DeprecationHelper.h"
 #include "Effect.h"
 #include "embed.h"
 #include "GuiApplication.h"
@@ -1027,19 +1028,19 @@ void DataFile::upgrade_0_4_0_beta1()
 		if( !k.isEmpty() )
 		{
 			const QList<QVariant> l =
-				base64::decode( k, QVariant::List ).toList();
+				base64::decode(k, QMetaType::QVariantList).toList();
 			if( !l.isEmpty() )
 			{
 				QString name = l[0].toString();
 				QVariant u = l[1];
 				EffectKey::AttributeMap m;
 				// VST-effect?
-				if( u.type() == QVariant::String )
+				if (typeId(u) == QMetaType::QString)
 				{
 					m["file"] = u.toString();
 				}
 				// LADSPA-effect?
-				else if( u.type() == QVariant::StringList )
+				else if (typeId(u) == QMetaType::QStringList)
 				{
 					const QStringList sl = u.toStringList();
 					m["plugin"] = sl.value( 0 );
@@ -2124,13 +2125,13 @@ void DataFile::loadData( const QByteArray & _data, const QString & _sourceFile )
 {
 	QString errorMsg;
 	int line = -1, col = -1;
-	if( !setContent( _data, &errorMsg, &line, &col ) )
+	if (!lmms::setContent(*this, _data, &errorMsg, &line, &col))
 	{
 		// parsing failed? then try to uncompress data
 		QByteArray uncompressed = qUncompress( _data );
 		if( !uncompressed.isEmpty() )
 		{
-			if( setContent( uncompressed, &errorMsg, &line, &col ) )
+			if (lmms::setContent(*this, uncompressed, &errorMsg, &line, &col))
 			{
 				line = col = -1;
 			}

src/core/InstrumentFunctions.cpp

@@ -489,9 +489,9 @@ void InstrumentFunctionArpeggio::processNote( NotePlayHandle * _n )
 		}
 		else
 		{
-			const auto octaveDiv = std::div(cur_arp_idx, total_chord_size);
+			const auto octaveDiv = std::div(cur_arp_idx, static_cast<int>(total_chord_size));
 			const int octave = octaveDiv.quot;
-			const auto arpDiv = std::div(octaveDiv.rem, cnphv.size());
+			const auto arpDiv = std::div(octaveDiv.rem, static_cast<int>(cnphv.size()));
 			const int arpIndex = arpDiv.rem;
 			const int chordIndex = arpDiv.quot;
 			sub_note_key = cnphv[arpIndex]->key()

src/core/base64.cpp

@@ -28,22 +28,24 @@
 #include <QBuffer>
 #include <QDataStream>
 
+#include "DeprecationHelper.h"
+
 namespace lmms::base64
 {
 
 
-QVariant decode( const QString & _b64, QVariant::Type _force_type )
+QVariant decode(const QString& b64, QMetaType::Type forceType)
 {
 	char * dst = nullptr;
 	int dsize = 0;
-	base64::decode( _b64, &dst, &dsize );
+	base64::decode(b64, &dst, &dsize);
 	QByteArray ba( dst, dsize );
 	QBuffer buf( &ba );
 	buf.open( QBuffer::ReadOnly );
 	QDataStream in( &buf );
 	QVariant ret;
 	in >> ret;
-	if( _force_type != QVariant::Invalid && ret.type() != _force_type )
+	if (forceType != QMetaType::UnknownType && typeId(ret) != forceType)
 	{
 		buf.reset();
 		in.setVersion( QDataStream::Qt_3_3 );

src/core/main.cpp

@@ -360,7 +360,12 @@ int main( int argc, char * * argv )
 		return EXIT_FAILURE;
 	}
 #endif
+
+#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
+	// High-DPI scaling is always enabled in Qt >= 6.0
 	QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
+#endif
+
 	QCoreApplication * app = coreOnly ?
 			new QCoreApplication( argc, argv ) :
 					new gui::MainApplication(argc, argv);

src/core/midi/MidiWinMM.cpp

@@ -275,15 +275,15 @@ void MidiWinMM::openDevices()
 	m_inputDevices.clear();
 	for( unsigned int i = 0; i < midiInGetNumDevs(); ++i )
 	{
-		MIDIINCAPS c;
-		midiInGetDevCaps( i, &c, sizeof( c ) );
+		MIDIINCAPSW c;
+		midiInGetDevCapsW(i, &c, sizeof(c));
 		HMIDIIN hm = 0;
 		MMRESULT res = midiInOpen( &hm, i, (DWORD_PTR) &inputCallback,
 						(DWORD_PTR) this,
 							CALLBACK_FUNCTION );
 		if( res == MMSYSERR_NOERROR )
 		{
-			m_inputDevices[hm] = qstrdup( c.szPname );
+			m_inputDevices[hm] = QString::fromWCharArray(c.szPname);
 			midiInStart( hm );
 		}
 	}
@@ -291,13 +291,13 @@ void MidiWinMM::openDevices()
 	m_outputDevices.clear();
 	for( unsigned int i = 0; i < midiOutGetNumDevs(); ++i )
 	{
-		MIDIOUTCAPS c;
-		midiOutGetDevCaps( i, &c, sizeof( c ) );
+		MIDIOUTCAPSW c;
+		midiOutGetDevCapsW(i, &c, sizeof(c));
 		HMIDIOUT hm = 0;
 		MMRESULT res = midiOutOpen( &hm, i, 0, 0, CALLBACK_NULL );
 		if( res == MMSYSERR_NOERROR )
 		{
-			m_outputDevices[hm] = qstrdup( c.szPname );
+			m_outputDevices[hm] = QString::fromWCharArray(c.szPname);
 		}
 	}
 }

src/gui/ControlLayout.cpp

@@ -141,7 +141,7 @@ int ControlLayout::count() const
 	return m_itemMap.size() - 1;
 }
 
-QMap<QString, QLayoutItem*>::const_iterator
+ControlLayout::ControlLayoutMap::const_iterator
 ControlLayout::pairAt(int index) const
 {
 	if (index < 0) { return m_itemMap.cend(); }
@@ -151,7 +151,7 @@ ControlLayout::pairAt(int index) const
 		return item->widget()->objectName() == s_searchBarName;
 	};
 
-	QMap<QString, QLayoutItem*>::const_iterator itr = m_itemMap.cbegin();
+	auto itr = m_itemMap.cbegin();
 	for (; itr != m_itemMap.cend() && (index > 0 || skip(itr.value())); ++itr)
 	{
 		if(!skip(itr.value())) { index--; }
@@ -242,10 +242,8 @@ int ControlLayout::doLayout(const QRect &rect, bool testOnly) const
 	const QString filterText = m_searchBar->text();
 	bool first = true;
 
-	QMapIterator<QString, QLayoutItem*> itr(m_itemMap);
-	while (itr.hasNext())
+	for (auto itr = m_itemMap.cbegin(); itr != m_itemMap.cend(); ++itr)
 	{
-		itr.next();
 		QLayoutItem* item = itr.value();
 		QWidget *wid = item->widget();
 		if (wid)

src/gui/ControllerRackView.cpp

@@ -169,13 +169,13 @@ void ControllerRackView::addController(Controller* controller)
 	connect(controllerView, &ControllerView::removedController, this, &ControllerRackView::deleteController, Qt::QueuedConnection);
 
 	auto moveUpAction = new QAction(controllerView);
-	moveUpAction->setShortcut(combine(Qt::Key_Up, Qt::AltModifier));
+	moveUpAction->setShortcut(keySequence(Qt::Key_Up, Qt::AltModifier));
 	moveUpAction->setShortcutContext(Qt::WidgetShortcut);
 	connect(moveUpAction, &QAction::triggered, controllerView, &ControllerView::moveUp);
 	controllerView->addAction(moveUpAction);
 
 	auto moveDownAction = new QAction(controllerView);
-	moveDownAction->setShortcut(combine(Qt::Key_Down, Qt::AltModifier));
+	moveDownAction->setShortcut(keySequence(Qt::Key_Down, Qt::AltModifier));
 	moveDownAction->setShortcutContext(Qt::WidgetShortcut);
 	connect(moveDownAction, &QAction::triggered, controllerView, &ControllerView::moveDown);
 	controllerView->addAction(moveDownAction);

src/gui/EffectRackView.cpp

@@ -179,13 +179,13 @@ void EffectRackView::update()
 			connect(view, &EffectView::deletedPlugin, this, &EffectRackView::deletePlugin, Qt::QueuedConnection);
 
 			QAction* moveUpAction = new QAction(view);
-			moveUpAction->setShortcut(combine(Qt::Key_Up, Qt::AltModifier));
+			moveUpAction->setShortcut(keySequence(Qt::Key_Up, Qt::AltModifier));
 			moveUpAction->setShortcutContext(Qt::WidgetShortcut);
 			connect(moveUpAction, &QAction::triggered, view, &EffectView::moveUp);
 			view->addAction(moveUpAction);
 
 			QAction* moveDownAction = new QAction(view);
-			moveDownAction->setShortcut(combine(Qt::Key_Down, Qt::AltModifier));
+			moveDownAction->setShortcut(keySequence(Qt::Key_Down, Qt::AltModifier));
 			moveDownAction->setShortcutContext(Qt::WidgetShortcut);
 			connect(moveDownAction, &QAction::triggered, view, &EffectView::moveDown);
 			view->addAction(moveDownAction);

src/gui/FileBrowser.cpp

@@ -43,6 +43,7 @@
 #include "AudioEngine.h"
 #include "ConfigManager.h"
 #include "DataFile.h"
+#include "DeprecationHelper.h"
 #include "Engine.h"
 #include "FileBrowser.h"
 #include "FileRevealer.h"
@@ -177,7 +178,13 @@ void FileBrowser::addContentCheckBox()
 	auto configCheckBox = [this](QBoxLayout* boxLayout, QCheckBox* box, Qt::CheckState checkState)
 	{
 		box->setCheckState(checkState);
-		connect(box, SIGNAL(stateChanged(int)), this, SLOT(reloadTree()));
+
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 7, 0))
+		connect(box, &QCheckBox::checkStateChanged, this, &FileBrowser::reloadTree);
+#else
+		connect(box, &QCheckBox::stateChanged, this, &FileBrowser::reloadTree);
+#endif
+
 		boxLayout->addWidget(box);
 	};
 
@@ -721,8 +728,10 @@ QList<QAction*> FileBrowserTreeWidget::getContextActions(FileItem* file, bool so
 
 void FileBrowserTreeWidget::mousePressEvent(QMouseEvent * me )
 {
+	const auto pos = position(me);
+
 	// Forward the event
-	QTreeWidgetItem * i = itemAt(me->pos());
+	QTreeWidgetItem* i = itemAt(pos);
 	QTreeWidget::mousePressEvent(me);
 	// QTreeWidget handles right clicks for us, so we only care about left clicks
 	if(me->button() != Qt::LeftButton) { return; }
@@ -730,13 +739,13 @@ void FileBrowserTreeWidget::mousePressEvent(QMouseEvent * me )
 	if (i)
 	{
 		// TODO: Restrict to visible selection
-//		if ( _me->x() > header()->cellPos( header()->mapToActual( 0 ) )
+//		if ( pos.x() > header()->cellPos( header()->mapToActual( 0 ) )
 //			+ treeStepSize() * ( i->depth() + ( rootIsDecorated() ?
 //						1 : 0 ) ) + itemMargin() ||
-//				_me->x() < header()->cellPos(
+//				pos.x() < header()->cellPos(
 //						header()->mapToActual( 0 ) ) )
 //		{
-			m_pressPos = me->pos();
+			m_pressPos = pos;
 			m_mousePressed = true;
 //		}
 	}
@@ -830,9 +839,7 @@ void FileBrowserTreeWidget::stopPreview()
 
 void FileBrowserTreeWidget::mouseMoveEvent( QMouseEvent * me )
 {
-	if( m_mousePressed == true &&
-		( m_pressPos - me->pos() ).manhattanLength() >
-					QApplication::startDragDistance() )
+	if (m_mousePressed && (m_pressPos - position(me)).manhattanLength() > QApplication::startDragDistance())
 	{
 		// make sure any playback is stopped
 		mouseReleaseEvent( nullptr );

src/gui/GuiApplication.cpp

@@ -308,9 +308,9 @@ void GuiApplication::sigintOccurred()
  */
 QFont GuiApplication::getWin32SystemFont()
 {
-	NONCLIENTMETRICS metrics = { sizeof( NONCLIENTMETRICS ) };
-	SystemParametersInfo( SPI_GETNONCLIENTMETRICS, sizeof( NONCLIENTMETRICS ), &metrics, 0 );
-	int pointSize = metrics.lfMessageFont.lfHeight;
+	auto metrics = NONCLIENTMETRICSW{ .cbSize = sizeof(NONCLIENTMETRICSW) };
+	SystemParametersInfoW(SPI_GETNONCLIENTMETRICS, sizeof(NONCLIENTMETRICSW), &metrics, 0);
+	int pointSize = static_cast<int>(metrics.lfMessageFont.lfHeight);
 	if ( pointSize < 0 )
 	{
 		// height is in pixels, convert to points
@@ -319,7 +319,7 @@ QFont GuiApplication::getWin32SystemFont()
 		ReleaseDC( nullptr, hDC );
 	}
 
-	return QFont( QString::fromUtf8( metrics.lfMessageFont.lfFaceName ), pointSize );
+	return QFont{QString::fromWCharArray(metrics.lfMessageFont.lfFaceName), pointSize};
 }
 #endif
 

src/gui/MainApplication.cpp

@@ -86,8 +86,8 @@ bool MainApplication::event(QEvent* event)
 }
 
 #ifdef LMMS_BUILD_WIN32
-// This can be moved into nativeEventFilter once Qt4 support has been dropped
-bool MainApplication::winEventFilter(MSG* msg, long* result)
+// Helper function for nativeEventFilter
+bool MainApplication::win32EventFilter(MSG* msg, FilterResult* result)
 {
 	switch(msg->message)
 	{
@@ -110,11 +110,11 @@ bool MainApplication::winEventFilter(MSG* msg, long* result)
 }
 
 bool MainApplication::nativeEventFilter(const QByteArray& eventType,
-					void* message, long* result)
+					void* message, FilterResult* result)
 {
 	if(eventType == "windows_generic_MSG")
 	{
-		return winEventFilter(static_cast<MSG *>(message), result);
+		return win32EventFilter(static_cast<MSG*>(message), result);
 	}
 	return false;
 }

src/gui/MainWindow.cpp

@@ -264,87 +264,79 @@ void MainWindow::finalize()
 	resetWindowTitle();
 	setWindowIcon( embed::getIconPixmap( "icon_small" ) );
 
+	auto addAction = [this](QMenu* menu, std::string_view icon, const QString& text,
+		const QKeySequence& shortcut, auto(MainWindow::* slot)()) -> QAction*
+	{
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 3, 0))
+		return menu->addAction(embed::getIconPixmap(icon), text, shortcut, this, slot);
+#else
+		return menu->addAction(embed::getIconPixmap(icon), text, this, slot, shortcut);
+#endif
+	};
 
 	// project-popup-menu
 	auto project_menu = new QMenu(this);
 	menuBar()->addMenu( project_menu )->setText( tr( "&File" ) );
-	project_menu->addAction( embed::getIconPixmap( "project_new" ),
-					tr( "&New" ),
-					this, SLOT(createNewProject()),
-					QKeySequence::New );
+
+	addAction(project_menu, "project_new", tr("&New"),
+		QKeySequence::New, &MainWindow::createNewProject);
 
 	auto templates_menu = new TemplatesMenu( this );
 	project_menu->addMenu(templates_menu);
 
-	project_menu->addAction( embed::getIconPixmap( "project_open" ),
-					tr( "&Open..." ),
-					this, SLOT(openProject()),
-					QKeySequence::Open );
+	addAction(project_menu, "project_open", tr("&Open..."),
+		QKeySequence::Open, &MainWindow::openProject);
 
 	project_menu->addMenu(new RecentProjectsMenu(this));
 
-	project_menu->addAction( embed::getIconPixmap( "project_save" ),
-					tr( "&Save" ),
-					this, SLOT(saveProject()),
-					QKeySequence::Save );
-	project_menu->addAction( embed::getIconPixmap( "project_save" ),
-					tr( "Save &As..." ),
-					this, SLOT(saveProjectAs()),
-					combine(Qt::CTRL, Qt::SHIFT, Qt::Key_S));
-	project_menu->addAction( embed::getIconPixmap( "project_save" ),
-					tr( "Save as New &Version" ),
-					this, SLOT(saveProjectAsNewVersion()),
-					combine(Qt::CTRL, Qt::ALT, Qt::Key_S));
+	addAction(project_menu, "project_save", tr("&Save"),
+		QKeySequence::Save, &MainWindow::saveProject);
 
-	project_menu->addAction( embed::getIconPixmap( "project_save" ),
-					tr( "Save as default template" ),
-					this, SLOT(saveProjectAsDefaultTemplate()));
+	addAction(project_menu, "project_save", tr("Save &As..."),
+		keySequence(Qt::CTRL, Qt::SHIFT, Qt::Key_S), &MainWindow::saveProjectAs);
+
+	addAction(project_menu, "project_save", tr("Save as New &Version"),
+		keySequence(Qt::CTRL, Qt::ALT, Qt::Key_S), &MainWindow::saveProjectAsNewVersion);
+
+	project_menu->addAction(embed::getIconPixmap("project_save"), tr("Save as default template"),
+		this, &MainWindow::saveProjectAsDefaultTemplate);
 
 	project_menu->addSeparator();
-	project_menu->addAction( embed::getIconPixmap( "project_import" ),
-					tr( "Import..." ),
-					this,
-					SLOT(onImportProject()));
-	project_menu->addAction( embed::getIconPixmap( "project_export" ),
-					tr( "E&xport..." ),
-					this,
-					SLOT(onExportProject()),
-					combine(Qt::CTRL, Qt::Key_E));
-	project_menu->addAction( embed::getIconPixmap( "project_export" ),
-					tr("Export &Tracks..."),
-					this,
-					SLOT(onExportProjectTracks()),
-					combine(Qt::CTRL, Qt::SHIFT, Qt::Key_E));
 
-	project_menu->addAction( embed::getIconPixmap( "midi_file" ),
-					tr( "Export &MIDI..." ),
-					this,
-					SLOT(onExportProjectMidi()),
-					combine(Qt::CTRL, Qt::Key_M));
+	project_menu->addAction(embed::getIconPixmap("project_import"), tr("Import..."),
+		this, &MainWindow::onImportProject);
+
+	addAction(project_menu, "project_export", tr("E&xport..."),
+		keySequence(Qt::CTRL, Qt::Key_E), &MainWindow::onExportProject);
+
+	addAction(project_menu, "project_export", tr("Export &Tracks..."),
+		keySequence(Qt::CTRL, Qt::SHIFT, Qt::Key_E), &MainWindow::onExportProjectTracks);
+
+	addAction(project_menu, "midi_file", tr("Export &MIDI..."),
+		keySequence(Qt::CTRL, Qt::Key_M), &MainWindow::onExportProjectMidi);
 
 	project_menu->addSeparator();
-	project_menu->addAction( embed::getIconPixmap( "exit" ), tr( "&Quit" ),
-					qApp, SLOT(closeAllWindows()),
-					combine(Qt::CTRL, Qt::Key_Q));
+
+	project_menu->addAction(embed::getIconPixmap("exit"), tr("&Quit"),
+		qApp, SLOT(closeAllWindows()))->setShortcut(keySequence(Qt::CTRL, Qt::Key_Q));
 
 	auto edit_menu = new QMenu(this);
 	menuBar()->addMenu( edit_menu )->setText( tr( "&Edit" ) );
-	m_undoAction = edit_menu->addAction( embed::getIconPixmap( "edit_undo" ),
-					tr( "Undo" ),
-					this, SLOT(undo()),
-					QKeySequence::Undo );
-	m_redoAction = edit_menu->addAction( embed::getIconPixmap( "edit_redo" ),
-					tr( "Redo" ),
-					this, SLOT(redo()),
-					QKeySequence::Redo );
+
+	m_undoAction = addAction(edit_menu, "edit_undo", tr("Undo"),
+		QKeySequence::Undo, &MainWindow::undo);
+
+	m_redoAction = addAction(edit_menu, "edit_redo", tr("Redo"),
+		QKeySequence::Redo, &MainWindow::redo);
+
 	// Ensure that both (Ctrl+Y) and (Ctrl+Shift+Z) activate redo shortcut regardless of OS defaults
-	if (QKeySequence(QKeySequence::Redo) != QKeySequence(combine(Qt::CTRL, Qt::Key_Y)))
+	if (QKeySequence(QKeySequence::Redo) != keySequence(Qt::CTRL, Qt::Key_Y))
 	{
-		new QShortcut(QKeySequence(combine(Qt::CTRL, Qt::Key_Y)), this, SLOT(redo()));
+		new QShortcut(keySequence(Qt::CTRL, Qt::Key_Y), this, SLOT(redo()));
 	}
-	if (QKeySequence(QKeySequence::Redo) != QKeySequence(combine(Qt::CTRL, Qt::SHIFT, Qt::Key_Z)))
+	if (QKeySequence(QKeySequence::Redo) != keySequence(Qt::CTRL, Qt::SHIFT, Qt::Key_Z))
 	{
-		new QShortcut(QKeySequence(combine(Qt::CTRL, Qt::SHIFT, Qt::Key_Z)), this, SLOT(redo()));
+		new QShortcut(keySequence(Qt::CTRL, Qt::SHIFT, Qt::Key_Z), this, SLOT(redo()));
 	}
 
 	edit_menu->addSeparator();
@@ -443,31 +435,31 @@ void MainWindow::finalize()
 	// window-toolbar
 	auto song_editor_window = new ToolButton(embed::getIconPixmap("songeditor"), tr("Song Editor") + " (Ctrl+1)", this,
 		SLOT(toggleSongEditorWin()), m_toolBar);
-	song_editor_window->setShortcut(combine(Qt::CTRL, Qt::Key_1));
+	song_editor_window->setShortcut(keySequence(Qt::CTRL, Qt::Key_1));
 
 	auto pattern_editor_window = new ToolButton(embed::getIconPixmap("pattern_track_btn"),
 		tr("Pattern Editor") + " (Ctrl+2)", this, SLOT(togglePatternEditorWin()), m_toolBar);
-	pattern_editor_window->setShortcut(combine(Qt::CTRL, Qt::Key_2));
+	pattern_editor_window->setShortcut(keySequence(Qt::CTRL, Qt::Key_2));
 
 	auto piano_roll_window = new ToolButton(
 		embed::getIconPixmap("piano"), tr("Piano Roll") + " (Ctrl+3)", this, SLOT(togglePianoRollWin()), m_toolBar);
-	piano_roll_window->setShortcut(combine(Qt::CTRL, Qt::Key_3));
+	piano_roll_window->setShortcut(keySequence(Qt::CTRL, Qt::Key_3));
 
 	auto automation_editor_window = new ToolButton(embed::getIconPixmap("automation"),
 		tr("Automation Editor") + " (Ctrl+4)", this, SLOT(toggleAutomationEditorWin()), m_toolBar);
-	automation_editor_window->setShortcut(combine(Qt::CTRL, Qt::Key_4));
+	automation_editor_window->setShortcut(keySequence(Qt::CTRL, Qt::Key_4));
 
 	auto mixer_window = new ToolButton(
 		embed::getIconPixmap("mixer"), tr("Mixer") + " (Ctrl+5)", this, SLOT(toggleMixerWin()), m_toolBar);
-	mixer_window->setShortcut(combine(Qt::CTRL, Qt::Key_5));
+	mixer_window->setShortcut(keySequence(Qt::CTRL, Qt::Key_5));
 
 	auto controllers_window = new ToolButton(embed::getIconPixmap("controller"),
 		tr("Show/hide controller rack") + " (Ctrl+6)", this, SLOT(toggleControllerRack()), m_toolBar);
-	controllers_window->setShortcut(combine(Qt::CTRL, Qt::Key_6));
+	controllers_window->setShortcut(keySequence(Qt::CTRL, Qt::Key_6));
 
 	auto project_notes_window = new ToolButton(embed::getIconPixmap("project_notes"),
 		tr("Show/hide project notes") + " (Ctrl+7)", this, SLOT(toggleProjectNotesWin()), m_toolBar);
-	project_notes_window->setShortcut(combine(Qt::CTRL, Qt::Key_7));
+	project_notes_window->setShortcut(keySequence(Qt::CTRL, Qt::Key_7));
 
 	m_toolBarLayout->addWidget( song_editor_window, 1, 1 );
 	m_toolBarLayout->addWidget( pattern_editor_window, 1, 2 );
@@ -620,15 +612,19 @@ bool MainWindow::mayChangeProject(bool stopPlayback)
 					"last saving. Do you want to save it "
 								"now?" );
 
-	QMessageBox mb( ( getSession() == SessionState::Recover ?
-				messageTitleRecovered : messageTitleUnsaved ),
-			( getSession() == SessionState::Recover ?
-					messageRecovered : messageUnsaved ),
-				QMessageBox::Question,
-				QMessageBox::Save,
-				QMessageBox::Discard,
-				QMessageBox::Cancel,
-				this );
+	const auto& title = getSession() == SessionState::Recover
+		? messageTitleRecovered
+		: messageTitleUnsaved;
+
+	const auto& text = getSession() == SessionState::Recover
+		? messageRecovered
+		: messageUnsaved;
+
+	const auto buttons = QMessageBox::Save
+		| QMessageBox::Discard
+		| QMessageBox::Cancel;
+
+	auto mb = QMessageBox{QMessageBox::Question, title, text, buttons, this};
 	int answer = mb.exec();
 
 	if( answer == QMessageBox::Save )
@@ -1607,8 +1603,9 @@ MainWindow::MovableQMdiArea::MovableQMdiArea(QWidget* parent) :
 
 void MainWindow::MovableQMdiArea::mousePressEvent(QMouseEvent* event)
 {
-	m_lastX = event->x();
-	m_lastY = event->y();
+	const auto pos = position(event);
+	m_lastX = pos.x();
+	m_lastY = pos.y();
 	m_isBeingMoved = true;
 	setCursor(Qt::ClosedHandCursor);
 }
@@ -1639,8 +1636,9 @@ void MainWindow::MovableQMdiArea::mouseMoveEvent(QMouseEvent* event)
 		}
 	}
 
-	int scrollX = m_lastX - event->x();
-	int scrollY = m_lastY - event->y();
+	const auto pos = position(event);
+	int scrollX = m_lastX - pos.x();
+	int scrollY = m_lastY - pos.y();
 
 	scrollX = scrollX < 0 && minX >= minXBoundary ? 0 : scrollX;
 	scrollX = scrollX > 0 && maxX <= maxXBoundary ? 0 : scrollX;
@@ -1657,8 +1655,8 @@ void MainWindow::MovableQMdiArea::mouseMoveEvent(QMouseEvent* event)
 		}
 	}
 
-	m_lastX = event->x();
-	m_lastY = event->y();
+	m_lastX = pos.x();
+	m_lastY = pos.y();
 }
 
 void MainWindow::MovableQMdiArea::mouseReleaseEvent(QMouseEvent* event)

src/gui/MixerChannelView.cpp

@@ -343,10 +343,16 @@ bool MixerChannelView::confirmRemoval(int index)
 	QString messageTitleRemoveTrack = tr("Confirm removal");
 	QString askAgainText = tr("Don't ask again");
 	auto askAgainCheckBox = new QCheckBox(askAgainText, nullptr);
-	connect(askAgainCheckBox, &QCheckBox::stateChanged, [](int state) {
+	auto onCheckedStateChanged = [](auto state) {
 		// Invert button state, if it's checked we *shouldn't* ask again
-		ConfigManager::inst()->setValue("ui", "mixerchanneldeletionwarning", state ? "0" : "1");
-	});
+		ConfigManager::inst()->setValue("ui", "mixerchanneldeletionwarning", state != Qt::Unchecked ? "0" : "1");
+	};
+
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 7, 0))
+	connect(askAgainCheckBox, &QCheckBox::checkStateChanged, onCheckedStateChanged);
+#else
+	connect(askAgainCheckBox, &QCheckBox::stateChanged, onCheckedStateChanged);
+#endif
 
 	QMessageBox mb;
 	mb.setText(messageRemoveTrack);

src/gui/PluginBrowser.cpp

@@ -258,13 +258,15 @@ void PluginDescWidget::paintEvent( QPaintEvent * )
 }
 
 
-
-
-void PluginDescWidget::enterEvent( QEvent * _e )
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+void PluginDescWidget::enterEvent(QEnterEvent* event)
+#else
+void PluginDescWidget::enterEvent(QEvent* event)
+#endif
 {
 	m_mouseOver = true;
 
-	QWidget::enterEvent( _e );
+	QWidget::enterEvent(event);
 }
 
 

src/gui/ProjectNotes.cpp

@@ -26,6 +26,7 @@
 #include "ProjectNotes.h"
 
 #include <QAction>
+#include <QActionGroup>
 #include <QApplication>
 #include <QCloseEvent>
 #include <QColorDialog>
@@ -146,8 +147,15 @@ void ProjectNotes::setupActions()
 	m_comboFont->setEditable( true );
 	QFontDatabase db;
 	m_comboFont->addItems( db.families() );
-	connect( m_comboFont, SIGNAL( activated( const QString& ) ),
-			m_edit, SLOT( setFontFamily( const QString& ) ) );
+
+	connect(m_comboFont,
+#if (QT_VERSION < QT_VERSION_CHECK(5, 14, 0))
+		QOverload<const QString&>::of(&QComboBox::activated),
+#else
+		&QComboBox::textActivated,
+#endif
+		m_edit, &QTextEdit::setFontFamily);
+
 	m_comboFont->lineEdit()->setText( QApplication::font().family() );
 
 	m_comboSize = new QComboBox( tb );
@@ -158,8 +166,15 @@ void ProjectNotes::setupActions()
 	{
 		m_comboSize->addItem( QString::number( *it ) );
 	}
-	connect( m_comboSize, SIGNAL( activated( const QString& ) ),
-		     this, SLOT( textSize( const QString& ) ) );
+
+	connect(m_comboSize,
+#if (QT_VERSION < QT_VERSION_CHECK(5, 14, 0))
+		QOverload<const QString&>::of(&QComboBox::activated),
+#else
+		&QComboBox::textActivated,
+#endif
+		this, &ProjectNotes::textSize);
+
 	m_comboSize->lineEdit()->setText( QString::number(
 					QApplication::font().pointSize() ) );
 

src/gui/SubWindow.cpp

@@ -81,7 +81,7 @@ SubWindow::SubWindow(QWidget *parent, Qt::WindowFlags windowFlags) :
 	// Disable the minimize button and make sure that the custom window hint is set
 	setWindowFlags((this->windowFlags() & ~Qt::WindowMinimizeButtonHint) | Qt::CustomizeWindowHint);
 
-	connect( mdiArea(), SIGNAL(subWindowActivated(QMdiSubWindow*)), this, SLOT(focusChanged(QMdiSubWindow*)));
+	connect(mdiArea(), &QMdiArea::subWindowActivated, this, &SubWindow::focusChanged);
 }
 
 

src/gui/clips/AutomationClipView.cpp

@@ -293,7 +293,9 @@ void AutomationClipView::paintEvent( QPaintEvent * )
 						m_clip->getTimeMap().begin();
 					it != m_clip->getTimeMap().end(); ++it )
 	{
-		if( it+1 == m_clip->getTimeMap().end() )
+		const auto nit = std::next(it);
+
+		if (nit == m_clip->getTimeMap().end())
 		{
 			const float x1 = POS(it) * ppTick + offset;
 			const auto x2 = (float)(width() - BORDER_WIDTH);
@@ -320,21 +322,21 @@ void AutomationClipView::paintEvent( QPaintEvent * )
 		// the next node.
 		float nextValue = m_clip->progressionType() == AutomationClip::ProgressionType::Discrete
 			? OUTVAL(it)
-			: INVAL(it + 1);
+			: INVAL(nit);
 
 		QPainterPath path;
 		QPointF origin = QPointF(POS(it) * ppTick + offset, 0.0f);
 		path.moveTo(origin);
 		path.moveTo(QPointF(POS(it) * ppTick + offset, values[0]));
-		for (int i = POS(it) + 1; i < POS(it + 1); i++)
+		for (int i = POS(it) + 1; i < POS(nit); ++i)
 		{
 			float x = i * ppTick + offset;
 			if(x > (width() - BORDER_WIDTH)) break;
 			float value = values[i - POS(it)];
 			path.lineTo(QPointF(x, value));
 		}
-		path.lineTo((POS(it + 1)) * ppTick + offset, nextValue);
-		path.lineTo((POS(it + 1)) * ppTick + offset, 0.0f);
+		path.lineTo((POS(nit)) * ppTick + offset, nextValue);
+		path.lineTo((POS(nit)) * ppTick + offset, 0.0f);
 		path.lineTo(origin);
 
 		if( gradient() )

src/gui/clips/ClipView.cpp

@@ -35,6 +35,7 @@
 #include "Clipboard.h"
 #include "ColorChooser.h"
 #include "DataFile.h"
+#include "DeprecationHelper.h"
 #include "Engine.h"
 #include "embed.h"
 #include "GuiApplication.h"
@@ -482,9 +483,11 @@ void ClipView::dropEvent( QDropEvent * de )
  */
 void ClipView::updateCursor(QMouseEvent * me)
 {
+	const auto posX = position(me).x();
+
 	// If we are at the edges, use the resize cursor
 	if (!me->buttons() && m_clip->manuallyResizable() && !isSelected()
-		&& ((me->x() > width() - RESIZE_GRIP_WIDTH) || (me->x() < RESIZE_GRIP_WIDTH)))
+		&& ((posX > width() - RESIZE_GRIP_WIDTH) || (posX < RESIZE_GRIP_WIDTH)))
 	{
 		setCursor(Qt::SizeHorCursor);
 	}
@@ -606,13 +609,15 @@ void ClipView::paintTextLabel(QString const & text, QPainter & painter)
  */
 void ClipView::mousePressEvent( QMouseEvent * me )
 {
+	const auto pos = position(me);
+
 	// Right now, active is only used on right/mid clicks actions, so we use a ternary operator
 	// to avoid the overhead of calling getClickedClips when it's not used
 	auto active = me->button() == Qt::LeftButton
 		? QVector<ClipView *>()
 		: getClickedClips();
 
-	setInitialPos( me->pos() );
+	setInitialPos(pos);
 	setInitialOffsets();
 	if( !fixedClips() && me->button() == Qt::LeftButton )
 	{
@@ -647,7 +652,7 @@ void ClipView::mousePressEvent( QMouseEvent * me )
 					m_clip->setJournalling(false);
 				}
 
-				setInitialPos( me->pos() );
+				setInitialPos(pos);
 				setInitialOffsets();
 
 				if (!m_clip->manuallyResizable() && !knifeMode)
@@ -655,12 +660,12 @@ void ClipView::mousePressEvent( QMouseEvent * me )
 					m_action = Action::Move;
 					setCursor( Qt::SizeAllCursor );
 				}
-				else if( me->x() >= width() - RESIZE_GRIP_WIDTH )
+				else if (pos.x() >= width() - RESIZE_GRIP_WIDTH)
 				{
 					m_action = Action::Resize;
 					setCursor( Qt::SizeHorCursor );
 				}
-				else if (me->x() < RESIZE_GRIP_WIDTH)
+				else if (pos.x() < RESIZE_GRIP_WIDTH)
 				{
 					m_action = Action::ResizeLeft;
 					setCursor( Qt::SizeHorCursor );
@@ -823,6 +828,7 @@ void ClipView::mouseMoveEvent( QMouseEvent * me )
 		m_hint = nullptr;
 	}
 
+	const auto pos = position(me);
 	const float ppb = m_trackView->trackContainerView()->pixelsPerBar();
 	if( m_action == Action::Move )
 	{
@@ -875,7 +881,7 @@ void ClipView::mouseMoveEvent( QMouseEvent * me )
 		if( m_action == Action::Resize )
 		{
 			// The clip's new length
-			TimePos l = static_cast<int>( me->x() * TimePos::ticksPerBar() / ppb );
+			TimePos l = static_cast<int>(pos.x() * TimePos::ticksPerBar() / ppb);
 
 			// If the user is holding alt, or pressed ctrl after beginning the drag, don't quantize
 			if ( unquantizedModHeld(me) )
@@ -910,7 +916,7 @@ void ClipView::mouseMoveEvent( QMouseEvent * me )
 		{
 			auto pClip = dynamic_cast<PatternClip*>(m_clip);
 
-			const int x = mapToParent( me->pos() ).x() - m_initialMousePos.x();
+			const int x = mapToParent(pos).x() - m_initialMousePos.x();
 
 			TimePos t = qMax( 0, (int)
 								m_trackView->trackContainerView()->currentPosition() +
@@ -1020,7 +1026,7 @@ void ClipView::mouseReleaseEvent( QMouseEvent * me )
 	else if( m_action == Action::Split )
 	{
 		const float ppb = m_trackView->trackContainerView()->pixelsPerBar();
-		const TimePos relPos = me->pos().x() * TimePos::ticksPerBar() / ppb;
+		const TimePos relPos = position(me).x() * TimePos::ticksPerBar() / ppb;
 		if (me->modifiers() & Qt::ShiftModifier)
 		{
 			destructiveSplitClip(unquantizedModHeld(me) ? relPos : quantizeSplitPos(relPos));
@@ -1282,7 +1288,7 @@ void ClipView::setInitialOffsets()
  */
 bool ClipView::mouseMovedDistance( QMouseEvent * me, int distance )
 {
-	QPoint dPos = mapToGlobal( me->pos() ) - m_initialMouseGlobalPos;
+	QPoint dPos = mapToGlobal(position(me)) - m_initialMouseGlobalPos;
 	const int pixelsMoved = dPos.manhattanLength();
 	return ( pixelsMoved > distance || pixelsMoved < -distance );
 }
@@ -1308,7 +1314,7 @@ TimePos ClipView::draggedClipPos( QMouseEvent * me )
 	//Pixels per bar
 	const float ppb = m_trackView->trackContainerView()->pixelsPerBar();
 	// The pixel distance that the mouse has moved
-	const int mouseOff = mapToGlobal(me->pos()).x() - m_initialMouseGlobalPos.x();
+	const int mouseOff = mapToGlobal(position(me)).x() - m_initialMouseGlobalPos.x();
 	TimePos newPos = m_initialClipPos + mouseOff * TimePos::ticksPerBar() / ppb;
 	TimePos offset = newPos - m_initialClipPos;
 	// If the user is holding alt, or pressed ctrl after beginning the drag, don't quantize
@@ -1340,7 +1346,7 @@ TimePos ClipView::draggedClipPos( QMouseEvent * me )
 int ClipView::knifeMarkerPos( QMouseEvent * me )
 {
 	//Position relative to start of clip
-	const int markerPos = me->pos().x();
+	const int markerPos = position(me).x();
 
 	//In unquantized mode, we don't have to mess with the position at all
 	if ( unquantizedModHeld(me) ) { return markerPos; }

src/gui/clips/MidiClipView.cpp

@@ -421,17 +421,19 @@ void MidiClipView::bulkClearNotesOutOfBounds(QVector<ClipView*> clipvs)
 
 void MidiClipView::mousePressEvent( QMouseEvent * _me )
 {
+	const auto pos = position(_me);
+
 	bool displayPattern = fixedClips() || (pixelsPerBar() >= 96 && m_legacySEPattern);
 	if (_me->button() == Qt::LeftButton && m_clip->m_clipType == MidiClip::Type::BeatClip && displayPattern
-		&& _me->y() > BeatStepButtonOffset && _me->y() < BeatStepButtonOffset + m_stepBtnOff.height())
+		&& pos.y() > BeatStepButtonOffset && pos.y() < BeatStepButtonOffset + m_stepBtnOff.height())
 
 	// when mouse button is pressed in pattern mode
 
 	{
 //	get the step number that was clicked on and
 //	do calculations in floats to prevent rounding errors...
-		float tmp = ( ( float(_me->x()) - BORDER_WIDTH ) *
-				float( m_clip -> m_steps ) ) / float(width() - BORDER_WIDTH*2);
+		float tmp = ((static_cast<float>(pos.x()) - BORDER_WIDTH)
+			* static_cast<float>(m_clip->m_steps)) / static_cast<float>(width() - BORDER_WIDTH * 2);
 
 		int step = int( tmp );
 

src/gui/editors/AutomationEditor.cpp

@@ -428,13 +428,15 @@ void AutomationEditor::mousePressEvent( QMouseEvent* mouseEvent )
 		}
 	};
 
+	const auto pos = position(mouseEvent);
+
 	// If we clicked inside the AutomationEditor viewport (where the nodes are represented)
-	if (mouseEvent->y() > TOP_MARGIN && mouseEvent->x() >= VALUES_WIDTH)
+	if (pos.y() > TOP_MARGIN && pos.x() >= VALUES_WIDTH)
 	{
-		float level = getLevel( mouseEvent->y() );
+		float level = getLevel(pos.y());
 
 		// Get the viewport X
-		int x = mouseEvent->x() - VALUES_WIDTH;
+		int x = pos.x() - VALUES_WIDTH;
 
 		// Get tick in which the user clicked
 		int posTicks = (x * TimePos::ticksPerBar() / m_ppb) + m_currentPosition;
@@ -453,7 +455,7 @@ void AutomationEditor::mousePressEvent( QMouseEvent* mouseEvent )
 			|| (m_editMode == EditMode::Erase && m_mouseDownRight)
 		);
 
-		timeMap::iterator clickedNode = getNodeAt(mouseEvent->x(), mouseEvent->y(), editingOutValue);
+		timeMap::iterator clickedNode = getNodeAt(pos.x(), pos.y(), editingOutValue);
 
 		switch (m_editMode)
 		{
@@ -622,7 +624,7 @@ void AutomationEditor::mousePressEvent( QMouseEvent* mouseEvent )
 				m_clip->addJournalCheckPoint();
 
 				// Gets the closest node to the mouse click
-				timeMap::iterator node = getClosestNode(mouseEvent->x());
+				timeMap::iterator node = getClosestNode(pos.x());
 
 				// Starts dragging a tangent
 				if (m_mouseDownLeft && node != tm.end())
@@ -663,14 +665,16 @@ void AutomationEditor::mousePressEvent( QMouseEvent* mouseEvent )
 
 void AutomationEditor::mouseDoubleClickEvent(QMouseEvent * mouseEvent)
 {
+	const auto pos = position(mouseEvent);
+
 	if (!validClip()) { return; }
 
 	// If we double clicked outside the AutomationEditor viewport return
-	if (mouseEvent->y() <= TOP_MARGIN || mouseEvent->x() < VALUES_WIDTH) { return; }
+	if (pos.y() <= TOP_MARGIN || pos.x() < VALUES_WIDTH) { return; }
 
 	// Are we fine tuning the inValue or outValue?
 	const bool isOutVal = (m_editMode == EditMode::DrawOutValues);
-	timeMap::iterator clickedNode = getNodeAt(mouseEvent->x(), mouseEvent->y(), isOutVal);
+	timeMap::iterator clickedNode = getNodeAt(pos.x(), pos.y(), isOutVal);
 
 	switch (m_editMode)
 	{
@@ -728,12 +732,14 @@ void AutomationEditor::mouseMoveEvent(QMouseEvent * mouseEvent )
 		return;
 	}
 
+	const auto pos = position(mouseEvent);
+
 	// If the mouse y position is inside the Automation Editor viewport
-	if (mouseEvent->y() > TOP_MARGIN)
+	if (pos.y() > TOP_MARGIN)
 	{
-		float level = getLevel(mouseEvent->y());
+		float level = getLevel(pos.y());
 		// Get the viewport X position where the mouse is at
-		int x = mouseEvent->x() - VALUES_WIDTH;
+		int x = pos.x() - VALUES_WIDTH;
 
 		// Get the X position in ticks
 		int posTicks = (x * TimePos::ticksPerBar() / m_ppb) + m_currentPosition;
@@ -882,8 +888,8 @@ void AutomationEditor::mouseMoveEvent(QMouseEvent * mouseEvent )
 						? yCoordOfLevel(OUTVAL(it))
 						: yCoordOfLevel(INVAL(it));
 					float dy = m_draggedOutTangent
-						? y - mouseEvent->y()
-						: mouseEvent->y() - y;
+						? y - pos.y()
+						: pos.y() - y;
 					float dx = std::abs(posTicks - POS(it));
 					float newTangent = dy / std::max(dx, 1.0f);
 
@@ -1314,11 +1320,13 @@ void AutomationEditor::paintEvent(QPaintEvent * pe )
 		if( time_map.size() > 0 )
 		{
 			timeMap::iterator it = time_map.begin();
-			while( it+1 != time_map.end() )
+			while (std::next(it) != time_map.end())
 			{
 				// skip this section if it occurs completely before the
 				// visible area
-				int next_x = xCoordOfTick(POS(it+1));
+				const auto nit = std::next(it);
+
+				int next_x = xCoordOfTick(POS(nit));
 				if( next_x < 0 )
 				{
 					++it;
@@ -1341,17 +1349,17 @@ void AutomationEditor::paintEvent(QPaintEvent * pe )
 				// the next node.
 				float nextValue = m_clip->progressionType() == AutomationClip::ProgressionType::Discrete
 					? OUTVAL(it)
-					: INVAL(it + 1);
+					: INVAL(nit);
 
 				p.setRenderHints( QPainter::Antialiasing, true );
 				QPainterPath path;
 				path.moveTo(QPointF(xCoordOfTick(POS(it)), yCoordOfLevel(0)));
-				for (int i = 0; i < POS(it + 1) - POS(it); i++)
+				for (int i = 0; i < POS(nit) - POS(it); ++i)
 				{
 					path.lineTo(QPointF(xCoordOfTick(POS(it) + i), yCoordOfLevel(values[i])));
 				}
-				path.lineTo(QPointF(xCoordOfTick(POS(it + 1)), yCoordOfLevel(nextValue)));
-				path.lineTo(QPointF(xCoordOfTick(POS(it + 1)), yCoordOfLevel(0)));
+				path.lineTo(QPointF(xCoordOfTick(POS(nit)), yCoordOfLevel(nextValue)));
+				path.lineTo(QPointF(xCoordOfTick(POS(nit)), yCoordOfLevel(0)));
 				path.lineTo(QPointF(xCoordOfTick(POS(it)), yCoordOfLevel(0)));
 				p.fillPath(path, m_graphColor);
 				p.setRenderHints( QPainter::Antialiasing, false );
@@ -2060,17 +2068,18 @@ AutomationEditorWindow::AutomationEditorWindow() :
 
 	auto editModeGroup = new ActionGroup(this);
 	m_drawAction = editModeGroup->addAction(embed::getIconPixmap("edit_draw"), tr("Draw mode (Shift+D)"));
-	m_drawAction->setShortcut(combine(Qt::SHIFT, Qt::Key_D));
+
+	m_drawAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_D));
 	m_drawAction->setChecked(true);
 
 	m_eraseAction = editModeGroup->addAction(embed::getIconPixmap("edit_erase"), tr("Erase mode (Shift+E)"));
-	m_eraseAction->setShortcut(combine(Qt::SHIFT, Qt::Key_E));
+	m_eraseAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_E));
 
 	m_drawOutAction = editModeGroup->addAction(embed::getIconPixmap("edit_draw_outvalue"), tr("Draw outValues mode (Shift+C)"));
-	m_drawOutAction->setShortcut(combine(Qt::SHIFT, Qt::Key_C));
+	m_drawOutAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_C));
 
 	m_editTanAction = editModeGroup->addAction(embed::getIconPixmap("edit_tangent"), tr("Edit tangents mode (Shift+T)"));
-	m_editTanAction->setShortcut(combine(Qt::SHIFT, Qt::Key_T));
+	m_editTanAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_T));
 	m_editTanAction->setEnabled(false);
 
 	m_flipYAction = new QAction(embed::getIconPixmap("flip_y"), tr("Flip vertically"), this);

src/gui/editors/Editor.cpp

@@ -120,7 +120,7 @@ Editor::Editor(bool record, bool stepRecord) :
 	connect(m_recordAccompanyAction, SIGNAL(triggered()), this, SLOT(recordAccompany()));
 	connect(m_toggleStepRecordingAction, SIGNAL(triggered()), this, SLOT(toggleStepRecording()));
 	connect(m_stopAction, SIGNAL(triggered()), this, SLOT(stop()));
-	new QShortcut(QKeySequence(combine(Qt::SHIFT, Qt::Key_F11)), this, SLOT(toggleMaximize()));
+	new QShortcut(keySequence(Qt::SHIFT, Qt::Key_F11), this, SLOT(toggleMaximize()));
 
 	// Add actions to toolbar
 	addButton(m_playAction, "playButton");

src/gui/editors/PianoRoll.cpp

@@ -1117,7 +1117,10 @@ void PianoRoll::drawDetuningInfo( QPainter & _p, const Note * _n, int _x,
 		{
 			// Previous node values (based on outValue). We just calculate
 			// the y level because the x will be the same as old_x.
-			const float pre_level = OUTVAL(it - 1);
+			const auto pit = std::prev(it);
+			const auto nit = std::next(it);
+
+			const float pre_level = OUTVAL(pit);
 			int pre_y = middle_y - pre_level * m_keyLineHeight;
 
 			// Draws the line representing the discrete jump if there's one
@@ -1142,7 +1145,7 @@ void PianoRoll::drawDetuningInfo( QPainter & _p, const Note * _n, int _x,
 
 			// If we are in the last node and there's a discrete jump, we draw a
 			// vertical line representing it
-			if ((it + 1) == map.end())
+			if (nit == map.end())
 			{
 				const float last_level = OUTVAL(it);
 				if (cur_level != last_level)
@@ -1631,6 +1634,8 @@ void PianoRoll::mousePressEvent(QMouseEvent * me )
 		return;
 	}
 
+	const auto pos = position(me);
+
 	// -- Knife
 	if (m_editMode == EditMode::Knife && me->button() == Qt::LeftButton)
 	{
@@ -1684,25 +1689,25 @@ void PianoRoll::mousePressEvent(QMouseEvent * me )
 	// keep track of the point where the user clicked down
 	if( me->button() == Qt::LeftButton )
 	{
-		m_moveStartX = me->x();
-		m_moveStartY = me->y();
+		m_moveStartX = pos.x();
+		m_moveStartY = pos.y();
 	}
 
-	if(me->button() == Qt::LeftButton &&
-		me->y() > keyAreaBottom() && me->y() < noteEditTop())
+	if (me->button() == Qt::LeftButton
+		&& pos.y() > keyAreaBottom() && pos.y() < noteEditTop())
 	{
 		// resizing the note edit area
 		m_action = Action::ResizeNoteEditArea;
 		return;
 	}
 
-	if( me->y() > PR_TOP_MARGIN )
+	if (pos.y() > PR_TOP_MARGIN)
 	{
-		bool edit_note = ( me->y() > noteEditTop() );
+		bool edit_note = (pos.y() > noteEditTop());
 
-		int key_num = getKey( me->y() );
+		int key_num = getKey(pos.y());
 
-		int x = me->x();
+		int x = pos.x();
 
 
 		if (x > m_whiteKeyWidth)
@@ -1959,7 +1964,7 @@ void PianoRoll::mousePressEvent(QMouseEvent * me )
 
 			update();
 		}
-		else if( me->y() < keyAreaBottom() )
+		else if (pos.y() < keyAreaBottom())
 		{
 			// reference to last key needed for both
 			// right click (used for copy all keys on note)
@@ -1970,8 +1975,8 @@ void PianoRoll::mousePressEvent(QMouseEvent * me )
 			if( me->buttons() == Qt::RightButton )
 			{
 				// right click - tone marker contextual menu
-				m_pianoKeySelected = getKey( me->y() );
-				m_semiToneMarkerMenu->popup( mapToGlobal( QPoint( me->x(), me->y() ) ) );
+				m_pianoKeySelected = getKey(pos.y());
+				m_semiToneMarkerMenu->popup(mapToGlobal(pos));
 			}
 			else if( me->buttons() == Qt::LeftButton )
 			{
@@ -1997,7 +2002,7 @@ void PianoRoll::mousePressEvent(QMouseEvent * me )
 			else if( me->buttons() == Qt::RightButton )
 			{
 				// pop menu asking which one they want to edit
-				m_noteEditMenu->popup( mapToGlobal( QPoint( me->x(), me->y() ) ) );
+				m_noteEditMenu->popup(mapToGlobal(pos));
 			}
 		}
 	}
@@ -2013,13 +2018,15 @@ void PianoRoll::mouseDoubleClickEvent(QMouseEvent * me )
 		return;
 	}
 
+	const auto pos = position(me);
+
 	// if they clicked in the note edit area, enter value for the volume bar
-	if( me->x() > noteEditLeft() && me->x() < noteEditRight()
-		&& me->y() > noteEditTop() && me->y() < noteEditBottom() )
+	if (pos.x() > noteEditLeft() && pos.x() < noteEditRight()
+		&& pos.y() > noteEditTop() && pos.y() < noteEditBottom())
 	{
 		// get values for going through notes
 		int pixel_range = 4;
-		int x = me->x() - m_whiteKeyWidth;
+		int x = pos.x() - m_whiteKeyWidth;
 		const int ticks_start = ( x-pixel_range/2 ) *
 					TimePos::ticksPerBar() / m_ppb + m_currentPosition;
 		const int ticks_end = ( x+pixel_range/2 ) *
@@ -2407,11 +2414,13 @@ void PianoRoll::mouseMoveEvent( QMouseEvent * me )
 		return;
 	}
 
+	const auto pos = position(me);
+
 	if( m_action == Action::None && me->buttons() == 0 )
 	{
 		// When cursor is between note editing area and volume/panning
 		// area show vertical size cursor.
-		if( me->y() > keyAreaBottom() && me->y() < noteEditTop() )
+		if (pos.y() > keyAreaBottom() && pos.y() < noteEditTop())
 		{
 			setCursor( Qt::SizeVerCursor );
 			return;
@@ -2420,12 +2429,12 @@ void PianoRoll::mouseMoveEvent( QMouseEvent * me )
 	else if( m_action == Action::ResizeNoteEditArea )
 	{
 		// Don't try to show more keys than the full keyboard, bail if trying to
-		if (m_pianoKeysVisible == NumKeys && me->y() > m_moveStartY)
+		if (m_pianoKeysVisible == NumKeys && pos.y() > m_moveStartY)
 		{
 			return;
 		}
-		int newHeight = height() - me->y();
-		if (me->y() < KEY_AREA_MIN_HEIGHT)
+		int newHeight = height() - pos.y();
+		if (pos.y() < KEY_AREA_MIN_HEIGHT)
 		{
 			newHeight = height() - KEY_AREA_MIN_HEIGHT -
 				PR_TOP_MARGIN - PR_BOTTOM_MARGIN; // - NOTE_EDIT_RESIZE_BAR
@@ -2452,14 +2461,14 @@ void PianoRoll::mouseMoveEvent( QMouseEvent * me )
 		updateStrumPos(me, false, me->modifiers() & Qt::ShiftModifier);
 	}
 
-	if( me->y() > PR_TOP_MARGIN || m_action != Action::None )
+	if (pos.y() > PR_TOP_MARGIN || m_action != Action::None)
 	{
-		bool edit_note = ( me->y() > noteEditTop() )
-						&& m_action != Action::SelectNotes;
+		bool edit_note = (pos.y() > noteEditTop())
+			&& m_action != Action::SelectNotes;
 
 
-		int key_num = getKey( me->y() );
-		int x = me->x();
+		int key_num = getKey(pos.y());
+		int x = pos.x();
 
 		// see if they clicked on the keyboard on the left
 		if (x < m_whiteKeyWidth && m_action == Action::None
@@ -2488,8 +2497,8 @@ void PianoRoll::mouseMoveEvent( QMouseEvent * me )
 			}
 
 			dragNotes(
-				me->x(),
-				me->y(),
+				pos.x(),
+				pos.y(),
 				me->modifiers() & Qt::AltModifier,
 				me->modifiers() & Qt::ShiftModifier,
 				me->modifiers() & Qt::ControlModifier
@@ -2528,29 +2537,26 @@ void PianoRoll::mouseMoveEvent( QMouseEvent * me )
 
 			if( me->buttons() & Qt::LeftButton )
 			{
-				vol = qBound<int>( MinVolume,
-								MinVolume +
-								( ( (float)noteEditBottom() ) - ( (float)me->y() ) ) /
-								( (float)( noteEditBottom() - noteEditTop() ) ) *
-								( MaxVolume - MinVolume ),
-											MaxVolume );
-				pan = qBound<int>( PanningLeft,
-								PanningLeft +
-								( (float)( noteEditBottom() - me->y() ) ) /
-								( (float)( noteEditBottom() - noteEditTop() ) ) *
-								( (float)( PanningRight - PanningLeft ) ),
-										  PanningRight);
+				vol = qBound(MinVolume, static_cast<volume_t>(MinVolume
+					+ static_cast<float>(noteEditBottom() - pos.y())
+					/ static_cast<float>(noteEditBottom() - noteEditTop())
+					* (MaxVolume - MinVolume)), MaxVolume);
+
+				pan = qBound(PanningLeft, static_cast<panning_t>(PanningLeft
+					+ static_cast<float>(noteEditBottom() - pos.y())
+					/ static_cast<float>(noteEditBottom() - noteEditTop())
+					* (PanningRight - PanningLeft)), PanningRight);
 			}
 
 			if( m_noteEditMode == NoteEditMode::Volume )
 			{
 				m_lastNoteVolume = vol;
-				showVolTextFloat( vol, me->pos() );
+				showVolTextFloat(vol, position(me));
 			}
 			else if( m_noteEditMode == NoteEditMode::Panning )
 			{
 				m_lastNotePanning = pan;
-				showPanTextFloat( pan, me->pos() );
+				showPanTextFloat(pan, position(me));
 			}
 
 			// When alt is pressed we only edit the note under the cursor
@@ -2746,8 +2752,8 @@ void PianoRoll::mouseMoveEvent( QMouseEvent * me )
 		setCursor( Qt::ArrowCursor );
 	}
 
-	m_lastMouseX = me->x();
-	m_lastMouseY = me->y();
+	m_lastMouseX = pos.x();
+	m_lastMouseY = pos.y();
 
 	update();
 }
@@ -2757,9 +2763,11 @@ void PianoRoll::mouseMoveEvent( QMouseEvent * me )
 
 void PianoRoll::updateKnifePos(QMouseEvent* me, bool initial)
 {
+	const auto pos = position(me);
+
 	// Calculate the TimePos from the mouse
-	int mouseViewportPosX = me->x() - m_whiteKeyWidth;
-	int mouseViewportPosY = keyAreaBottom() - 1 - me->y();
+	int mouseViewportPosX = pos.x() - m_whiteKeyWidth;
+	int mouseViewportPosY = keyAreaBottom() - 1 - pos.y();
 	int mouseTickPos = mouseViewportPosX * TimePos::ticksPerBar() / m_ppb + m_currentPosition;
 	int mouseKey = std::round(1.f * mouseViewportPosY / m_keyLineHeight) + m_startKey - 1;
 
@@ -2824,16 +2832,17 @@ void PianoRoll::updateStrumPos(QMouseEvent* me, bool initial, bool warp)
 {
 	if (!hasValidMidiClip()) { return; }
 	// Calculate the TimePos from the mouse
-	int mouseViewportPos = me->x() - m_whiteKeyWidth;
+	const auto pos = position(me);
+	int mouseViewportPos = pos.x() - m_whiteKeyWidth;
 	int mouseTickPos = mouseViewportPos * TimePos::ticksPerBar() / m_ppb + m_currentPosition;
 	// Should we add quantization? probably not?
 	if (initial)
 	{
 		m_strumStartTime = mouseTickPos;
-		m_strumStartVertical =  me->y();
+		m_strumStartVertical =  pos.y();
 	}
 	m_strumCurrentTime = mouseTickPos;
-	m_strumCurrentVertical =  me->y();
+	m_strumCurrentVertical =  pos.y();
 	int strumTicksHorizontal = m_strumCurrentTime - m_strumStartTime;
 	float strumPower = fastPow10f(0.01f * (m_strumCurrentVertical - m_strumStartVertical));
 
@@ -3923,8 +3932,8 @@ void PianoRoll::wheelEvent(QWheelEvent * we )
 			{
 				for ( Note * n : nv )
 				{
-					panning_t pan = qBound<int>( PanningLeft, n->getPanning() + step, PanningRight );
-					n->setPanning( pan );
+					panning_t pan = qBound(PanningLeft, static_cast<panning_t>(n->getPanning() + step), PanningRight);
+					n->setPanning(pan);
 				}
 				bool allPansEqual = std::all_of( nv.begin(), nv.end(),
 					[nv](const Note *note)
@@ -4902,10 +4911,10 @@ PianoRollWindow::PianoRollWindow() :
 
 	drawAction->setChecked( true );
 
-	drawAction->setShortcut(combine(Qt::SHIFT, Qt::Key_D));
-	eraseAction->setShortcut(combine(Qt::SHIFT, Qt::Key_E));
-	selectAction->setShortcut(combine(Qt::SHIFT, Qt::Key_S));
-	pitchBendAction->setShortcut(combine(Qt::SHIFT, Qt::Key_T));
+	drawAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_D ));
+	eraseAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_E));
+	selectAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_S));
+	pitchBendAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_T));
 
 	connect( editModeGroup, SIGNAL(triggered(int)), m_editor, SLOT(setEditMode(int)));
 
@@ -4964,9 +4973,9 @@ PianoRollWindow::PianoRollWindow() :
 
 	auto pasteAction = new QAction(embed::getIconPixmap("edit_paste"), tr("Paste (%1+V)").arg(UI_CTRL_KEY), this);
 
-	cutAction->setShortcut(combine(Qt::CTRL, Qt::Key_X));
-	copyAction->setShortcut(combine(Qt::CTRL, Qt::Key_C));
-	pasteAction->setShortcut(combine(Qt::CTRL, Qt::Key_V));
+	cutAction->setShortcut(keySequence(Qt::CTRL, Qt::Key_X));
+	copyAction->setShortcut(keySequence(Qt::CTRL, Qt::Key_C));
+	pasteAction->setShortcut(keySequence(Qt::CTRL, Qt::Key_V));
 
 	connect( cutAction, SIGNAL(triggered()), m_editor, SLOT(cutSelectedNotes()));
 	connect( copyAction, SIGNAL(triggered()), m_editor, SLOT(copySelectedNotes()));
@@ -4987,23 +4996,23 @@ PianoRollWindow::PianoRollWindow() :
 
 	auto glueAction = new QAction(embed::getIconPixmap("glue"), tr("Glue"), noteToolsButton);
 	connect(glueAction, SIGNAL(triggered()), m_editor, SLOT(glueNotes()));
-	glueAction->setShortcut(combine(Qt::SHIFT, Qt::Key_G));
+	glueAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_G));
 
 	auto knifeAction = new QAction(embed::getIconPixmap("edit_knife"), tr("Knife"), noteToolsButton);
 	connect(knifeAction, &QAction::triggered, m_editor, &PianoRoll::setKnifeAction);
-	knifeAction->setShortcut(combine(Qt::SHIFT, Qt::Key_K));
+	knifeAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_K));
 
 	auto strumAction = new QAction(embed::getIconPixmap("arp_free"), tr("Strum"), noteToolsButton);
 	connect(strumAction, &QAction::triggered, m_editor, &PianoRoll::setStrumAction);
-	strumAction->setShortcut(combine(Qt::SHIFT, Qt::Key_J));
+	strumAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_J));
 
 	auto fillAction = new QAction(embed::getIconPixmap("fill"), tr("Fill"), noteToolsButton);
 	connect(fillAction, &QAction::triggered, [this](){ m_editor->fitNoteLengths(true); });
-	fillAction->setShortcut(combine(Qt::SHIFT, Qt::Key_F));
+	fillAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_F));
 
 	auto cutOverlapsAction = new QAction(embed::getIconPixmap("cut_overlaps"), tr("Cut overlaps"), noteToolsButton);
 	connect(cutOverlapsAction, &QAction::triggered, [this](){ m_editor->fitNoteLengths(false); });
-	cutOverlapsAction->setShortcut(combine(Qt::SHIFT, Qt::Key_C));
+	cutOverlapsAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_C));
 
 	auto minLengthAction = new QAction(embed::getIconPixmap("min_length"), tr("Min length as last"), noteToolsButton);
 	connect(minLengthAction, &QAction::triggered, [this](){ m_editor->constrainNoteLengths(false); });
@@ -5013,7 +5022,7 @@ PianoRollWindow::PianoRollWindow() :
 
 	auto reverseAction = new QAction(embed::getIconPixmap("flip_x"), tr("Reverse Notes"), noteToolsButton);
 	connect(reverseAction, &QAction::triggered, [this](){ m_editor->reverseNotes(); });
-	reverseAction->setShortcut(combine(Qt::SHIFT, Qt::Key_R));
+	reverseAction->setShortcut(keySequence(Qt::SHIFT, Qt::Key_R));
 
 	noteToolsButton->addAction(glueAction);
 	noteToolsButton->addAction(knifeAction);

src/gui/editors/SongEditor.cpp

@@ -587,11 +587,13 @@ void SongEditor::closeEvent( QCloseEvent * ce )
 
 void SongEditor::mousePressEvent(QMouseEvent *me)
 {
+	const auto pos = position(me);
+	
 	if (allowRubberband())
 	{
 		//we save the position of scrollbars, mouse position and zooming level
 		m_scrollPos = QPoint(m_leftRightScroll->value(), contentWidget()->verticalScrollBar()->value());
-		m_origin = contentWidget()->mapFromParent(QPoint(me->pos().x(), me->pos().y()));
+		m_origin = contentWidget()->mapFromParent(pos);
 		m_rubberbandPixelsPerBar = pixelsPerBar();
 
 		//paint the rubberband
@@ -600,8 +602,8 @@ void SongEditor::mousePressEvent(QMouseEvent *me)
 		rubberBand()->show();
 
 		//the trackView(index) and the time position where the mouse was clicked
-		m_rubberBandStartTrackview = trackIndexFromSelectionPoint(me->y());
-		m_rubberbandStartTimePos = TimePos((me->x() - m_trackHeadWidth)
+		m_rubberBandStartTrackview = trackIndexFromSelectionPoint(pos.y());
+		m_rubberbandStartTimePos = TimePos((pos.x() - m_trackHeadWidth)
 											/ pixelsPerBar() * TimePos::ticksPerBar())
 											+ m_currentPosition;
 	}
@@ -613,7 +615,7 @@ void SongEditor::mousePressEvent(QMouseEvent *me)
 
 void SongEditor::mouseMoveEvent(QMouseEvent *me)
 {
-	m_mousePos = me->pos();
+	m_mousePos = position(me);
 	updateRubberband();
 	QWidget::mouseMoveEvent(me);
 }

src/gui/editors/TimeLineWidget.cpp

@@ -33,6 +33,7 @@
 #include <QToolBar>
 
 #include "ConfigManager.h"
+#include "DeprecationHelper.h"
 #include "embed.h"
 #include "KeyboardShortcuts.h"
 #include "NStateButton.h"
@@ -239,8 +240,10 @@ auto TimeLineWidget::getClickedTime(const int xPosition) const -> TimePos
 
 auto TimeLineWidget::getLoopAction(QMouseEvent* event) const -> TimeLineWidget::Action
 {
+	const auto pos = position(event);
+
 	const auto mode = ConfigManager::inst()->value("app", "loopmarkermode");
-	const auto xPos = event->x();
+	const auto xPos = pos.x();
 	const auto button = event->button();
 
 	if (mode == "handles")
@@ -283,7 +286,9 @@ auto TimeLineWidget::actionCursor(Action action) const -> QCursor
 
 void TimeLineWidget::mousePressEvent(QMouseEvent* event)
 {
-	if (event->x() < m_xOffset) { return; }
+	const auto pos = position(event);
+
+	if (pos.x() < m_xOffset) { return; }
 
 	const auto shift = event->modifiers() & Qt::ShiftModifier;
 	const auto ctrl = event->modifiers() & Qt::ControlModifier;
@@ -295,14 +300,14 @@ void TimeLineWidget::mousePressEvent(QMouseEvent* event)
 
 		if (m_action == Action::MoveLoop)
 		{
-			m_dragStartPos = getClickedTime(event->x());
+			m_dragStartPos = getClickedTime(pos.x());
 			m_oldLoopPos = {m_timeline->loopBegin(), m_timeline->loopEnd()};
 		}
 	}
 	else if (event->button() == Qt::LeftButton && ctrl) // selection
 	{
 		m_action = Action::SelectSongClip;
-		m_initalXSelect = event->x();
+		m_initalXSelect = pos.x();
 	}
 	else if (event->button() == Qt::LeftButton && !ctrl) // move playhead
 	{
@@ -326,7 +331,9 @@ void TimeLineWidget::mouseMoveEvent( QMouseEvent* event )
 {
 	parentWidget()->update(); // essential for widgets that this timeline had taken their mouse move event from.
 
-	auto timeAtCursor = getClickedTime(event->x());
+	const auto pos = position(event);
+
+	auto timeAtCursor = getClickedTime(pos.x());
 	const auto control = event->modifiers() & Qt::ControlModifier;
 
 	switch( m_action )
@@ -387,7 +394,7 @@ void TimeLineWidget::mouseMoveEvent( QMouseEvent* event )
 			break;
 		}
 		case Action::SelectSongClip:
-			emit regionSelectedFromPixels( m_initalXSelect , event->x() );
+			emit regionSelectedFromPixels(m_initalXSelect, pos.x());
 			break;
 
 		default:

src/gui/embed.cpp

@@ -110,7 +110,7 @@ auto getIconPixmap(std::string_view name, int width, int height, const char* con
 
 	const auto pixmapName = QString::fromUtf8(name.data(), name.size());
 	const auto cacheName = (width > 0 && height > 0)
-		? QStringLiteral("%1_%2_%3").arg(pixmapName, width, height)
+		? QStringLiteral("%1_%2_%3").arg(pixmapName).arg(width).arg(height)
 		: pixmapName;
 
 	// Return cached pixmap if it exists

src/gui/instrument/PianoView.cpp

@@ -45,6 +45,7 @@
 #include <QVBoxLayout>
 
 #include "AutomatableModelView.h"
+#include "DeprecationHelper.h"
 #include "PianoView.h"
 #include "Piano.h"
 #include "CaptionMenu.h"
@@ -417,11 +418,13 @@ void PianoView::mousePressEvent(QMouseEvent *me)
 {
 	if (me->button() == Qt::LeftButton && m_piano != nullptr)
 	{
+		const auto pos = position(me);
+
 		// get pressed key
-		int key_num = getKeyFromMouse(me->pos());
-		if (me->pos().y() > PIANO_BASE)
+		int key_num = getKeyFromMouse(pos);
+		if (pos.y() > PIANO_BASE)
 		{
-			int y_diff = me->pos().y() - PIANO_BASE;
+			int y_diff = pos.y() - PIANO_BASE;
 			int velocity = static_cast<int>(
 				static_cast<float>(y_diff) / getKeyHeight(key_num) *
 				m_piano->instrumentTrack()->midiPort()->baseVelocity());
@@ -519,8 +522,10 @@ void PianoView::mouseMoveEvent( QMouseEvent * _me )
 		return;
 	}
 
-	int key_num = getKeyFromMouse( _me->pos() );
-	int y_diff = _me->pos().y() - PIANO_BASE;
+	const auto pos = position(_me);
+
+	int key_num = getKeyFromMouse(pos);
+	int y_diff = pos.y() - PIANO_BASE;
 	int velocity = (int)( (float) y_diff /
 		( Piano::isWhiteKey( key_num ) ?
 			PW_WHITE_KEY_HEIGHT : PW_BLACK_KEY_HEIGHT ) *
@@ -551,7 +556,7 @@ void PianoView::mouseMoveEvent( QMouseEvent * _me )
 		}
 		if( _me->buttons() & Qt::LeftButton )
 		{
-			if( _me->pos().y() > PIANO_BASE )
+			if (pos.y() > PIANO_BASE)
 			{
 				m_piano->midiEventProcessor()->processInEvent( MidiEvent( MidiNoteOn, -1, key_num, velocity ) );
 				m_piano->setKeyState( key_num, true );

src/gui/modals/SetupDialog.cpp

@@ -550,8 +550,13 @@ SetupDialog::SetupDialog(ConfigTab tab_to_open) :
 		setCurrentIndex(m_audioInterfaces->findText(audioDevName));
 	m_audioIfaceSetupWidgets[audioDevName]->show();
 
-	connect(m_audioInterfaces, SIGNAL(activated(const QString&)),
-			this, SLOT(audioInterfaceChanged(const QString&)));
+	connect(m_audioInterfaces,
+#if (QT_VERSION < QT_VERSION_CHECK(5, 14, 0))
+		QOverload<const QString&>::of(&QComboBox::activated),
+#else
+		&QComboBox::textActivated,
+#endif
+		this, &SetupDialog::audioInterfaceChanged);
 
 	// Advanced setting, hidden for now
 	// // TODO Handle or remove.
@@ -725,9 +730,13 @@ SetupDialog::SetupDialog(ConfigTab tab_to_open) :
 	m_midiInterfaces->setCurrentIndex(m_midiInterfaces->findText(midiDevName));
 	m_midiIfaceSetupWidgets[midiDevName]->show();
 
-	connect(m_midiInterfaces, SIGNAL(activated(const QString&)),
-			this, SLOT(midiInterfaceChanged(const QString&)));
-
+	connect(m_midiInterfaces,
+#if (QT_VERSION < QT_VERSION_CHECK(5, 14, 0))
+		QOverload<const QString&>::of(&QComboBox::activated),
+#else
+		&QComboBox::textActivated,
+#endif
+		this, &SetupDialog::midiInterfaceChanged);
 
 	// MIDI autoassign group
 	QGroupBox * midiAutoAssignBox = new QGroupBox(tr("Automatically assign MIDI controller to selected track"), midi_w);

src/gui/tracks/AutomationTrackView.cpp

@@ -26,6 +26,7 @@
 #include "AutomationTrackView.h"
 #include "AutomationClip.h"
 #include "AutomationTrack.h"
+#include "DeprecationHelper.h"
 #include "embed.h"
 #include "Engine.h"
 #include "ProjectJournal.h"
@@ -64,13 +65,10 @@ void AutomationTrackView::dropEvent( QDropEvent * _de )
 		auto mod = dynamic_cast<AutomatableModel*>(Engine::projectJournal()->journallingObject(val.toInt()));
 		if( mod != nullptr )
 		{
-			TimePos pos = TimePos( trackContainerView()->
-							currentPosition() +
-				( _de->pos().x() -
-					getTrackContentWidget()->x() ) *
-						TimePos::ticksPerBar() /
-		static_cast<int>( trackContainerView()->pixelsPerBar() ) )
-				.toAbsoluteBar();
+			const int deX = position(_de).x();
+			TimePos pos = TimePos(trackContainerView()->currentPosition()
+				+ (deX - getTrackContentWidget()->x()) * TimePos::ticksPerBar()
+				/ static_cast<int>(trackContainerView()->pixelsPerBar())).toAbsoluteBar();
 
 			if( pos.getTicks() < 0 )
 			{

src/gui/tracks/SampleTrackView.cpp

@@ -31,6 +31,7 @@
 #include <QVBoxLayout>
 
 #include "ConfigManager.h"
+#include "DeprecationHelper.h"
 #include "embed.h"
 #include "Engine.h"
 #include "FadeButton.h"
@@ -207,9 +208,10 @@ void SampleTrackView::dropEvent(QDropEvent *de)
 				? DEFAULT_SETTINGS_WIDGET_WIDTH_COMPACT + TRACK_OP_WIDTH_COMPACT
 				: DEFAULT_SETTINGS_WIDGET_WIDTH + TRACK_OP_WIDTH;
 
-		int xPos = de->pos().x() < trackHeadWidth
+		const int deX = position(de).x();
+		int xPos = deX < trackHeadWidth
 				? trackHeadWidth
-				: de->pos().x();
+				: deX;
 
 		const float snapSize = getGUI()->songEditor()->m_editor->getSnapSize();
 		TimePos clipPos = trackContainerView()->fixedClips()

src/gui/tracks/TrackContentWidget.cpp

@@ -32,6 +32,7 @@
 #include "AutomationClip.h"
 #include "Clipboard.h"
 #include "DataFile.h"
+#include "DeprecationHelper.h"
 #include "Engine.h"
 #include "GuiApplication.h"
 #include "PatternEditor.h"
@@ -321,7 +322,7 @@ TimePos TrackContentWidget::getPosition( int mouseX )
  */
 void TrackContentWidget::dragEnterEvent( QDragEnterEvent * dee )
 {
-	TimePos clipPos = getPosition( dee->pos().x() );
+	TimePos clipPos = getPosition(position(dee).x());
 	if( canPasteSelection( clipPos, dee ) == false )
 	{
 		dee->ignore();
@@ -557,7 +558,9 @@ bool TrackContentWidget::pasteSelection( TimePos clipPos, const QMimeData * md,
  */
 void TrackContentWidget::dropEvent( QDropEvent * de )
 {
-	TimePos clipPos = TimePos( getPosition( de->pos().x() ) );
+	const auto pos = position(de);
+
+	TimePos clipPos = TimePos(getPosition(pos.x()));
 	if( pasteSelection( clipPos, de ) == true )
 	{
 		de->accept();
@@ -573,6 +576,8 @@ void TrackContentWidget::dropEvent( QDropEvent * de )
  */
 void TrackContentWidget::mousePressEvent( QMouseEvent * me )
 {
+	const auto pos = position(me);
+
 	// Enable box select if control is held when clicking an empty space
 	// (If we had clicked a Clip it would have intercepted the mouse event)
 	if( me->modifiers() & Qt::ControlModifier ){
@@ -599,8 +604,8 @@ void TrackContentWidget::mousePressEvent( QMouseEvent * me )
 		}
 		getTrack()->addJournalCheckPoint();
 		const float snapSize = getGUI()->songEditor()->m_editor->getSnapSize();
-		const TimePos pos = TimePos(getPosition(me->x())).quantize(snapSize, true);
-		getTrack()->createClip(pos);
+		const TimePos timePos = TimePos(getPosition(pos.x())).quantize(snapSize, true);
+		getTrack()->createClip(timePos);
 	}
 }
 

src/gui/tracks/TrackLabelButton.cpp

@@ -29,6 +29,7 @@
 #include <QMouseEvent>
 
 #include "ConfigManager.h"
+#include "DeprecationHelper.h"
 #include "embed.h"
 #include "Instrument.h"
 #include "InstrumentTrack.h"
@@ -181,7 +182,8 @@ void TrackLabelButton::mouseDoubleClickEvent( QMouseEvent * _me )
 
 void TrackLabelButton::mouseReleaseEvent( QMouseEvent *_me )
 {
-	if( m_buttonRect.contains( _me->globalPos(), true ) && m_renameLineEdit->isHidden() )
+	const auto globalPos = globalPosition(_me);
+	if (m_buttonRect.contains(globalPos, true) && m_renameLineEdit->isHidden())
 	{
 		QToolButton::mousePressEvent( _me );
 	}

src/gui/tracks/TrackOperationsWidget.cpp

@@ -175,10 +175,16 @@ bool TrackOperationsWidget::confirmRemoval()
 	QString messageTitleRemoveTrack = tr("Confirm removal");
 	QString askAgainText = tr("Don't ask again");
 	auto askAgainCheckBox = new QCheckBox(askAgainText, nullptr);
-	connect(askAgainCheckBox, &QCheckBox::stateChanged, [](int state){
+	auto onCheckedStateChanged = [](auto state){
 		// Invert button state, if it's checked we *shouldn't* ask again
-		ConfigManager::inst()->setValue("ui", "trackdeletionwarning", state ? "0" : "1");
-	});
+		ConfigManager::inst()->setValue("ui", "trackdeletionwarning", state != Qt::Unchecked ? "0" : "1");
+	};
+
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 7, 0))
+	connect(askAgainCheckBox, &QCheckBox::checkStateChanged, onCheckedStateChanged);
+#else
+	connect(askAgainCheckBox, &QCheckBox::stateChanged, onCheckedStateChanged);
+#endif
 
 	QMessageBox mb;
 	mb.setText(messageRemoveTrack);

src/gui/tracks/TrackView.cpp

@@ -36,6 +36,7 @@
 #include "AutomatableButton.h"
 #include "ConfigManager.h"
 #include "DataFile.h"
+#include "DeprecationHelper.h"
 #include "Engine.h"
 #include "FadeButton.h"
 #include "StringPairDrag.h"
@@ -259,6 +260,7 @@ void TrackView::dropEvent( QDropEvent * de )
  */
 void TrackView::mousePressEvent( QMouseEvent * me )
 {
+	const auto pos = position(me);
 
 	// If previously dragged too small, restore on shift-leftclick
 	if( height() < DEFAULT_TRACK_HEIGHT &&
@@ -274,7 +276,7 @@ void TrackView::mousePressEvent( QMouseEvent * me )
 							"compacttrackbuttons" ).toInt()==1 ?
 		DEFAULT_SETTINGS_WIDGET_WIDTH_COMPACT + TRACK_OP_WIDTH_COMPACT :
 		DEFAULT_SETTINGS_WIDGET_WIDTH + TRACK_OP_WIDTH;
-	if( m_trackContainerView->allowRubberband() == true  && me->x() > widgetTotal )
+	if (m_trackContainerView->allowRubberband() == true  && pos.x() > widgetTotal)
 	{
 		QWidget::mousePressEvent( me );
 	}
@@ -283,10 +285,8 @@ void TrackView::mousePressEvent( QMouseEvent * me )
 		if( me->modifiers() & Qt::ShiftModifier )
 		{
 			m_action = Action::Resize;
-			QCursor::setPos( mapToGlobal( QPoint( me->x(),
-								height() ) ) );
-			QCursor c( Qt::SizeVerCursor);
-			QApplication::setOverrideCursor( c );
+			QCursor::setPos(mapToGlobal(QPoint(pos.x(), height())));
+			QApplication::setOverrideCursor(Qt::SizeVerCursor);
 		}
 
 		me->accept();
@@ -318,11 +318,13 @@ void TrackView::mousePressEvent( QMouseEvent * me )
  */
 void TrackView::mouseMoveEvent( QMouseEvent * me )
 {
+	const auto pos = position(me);
+
 	int widgetTotal = ConfigManager::inst()->value( "ui",
 							"compacttrackbuttons" ).toInt()==1 ?
 		DEFAULT_SETTINGS_WIDGET_WIDTH_COMPACT + TRACK_OP_WIDTH_COMPACT :
 		DEFAULT_SETTINGS_WIDGET_WIDTH + TRACK_OP_WIDTH;
-	if( m_trackContainerView->allowRubberband() == true && me->x() > widgetTotal )
+	if (m_trackContainerView->allowRubberband() == true && pos.x() > widgetTotal)
 	{
 		QWidget::mouseMoveEvent( me );
 	}
@@ -330,7 +332,7 @@ void TrackView::mouseMoveEvent( QMouseEvent * me )
 	{
 		// look which track-widget the mouse-cursor is over
 		const int yPos =
-			m_trackContainerView->contentWidget()->mapFromGlobal( me->globalPos() ).y();
+			m_trackContainerView->contentWidget()->mapFromGlobal(globalPosition(me)).y();
 		const TrackView * trackAtY = m_trackContainerView->trackViewAt( yPos );
 
 		// debug code
@@ -340,7 +342,7 @@ void TrackView::mouseMoveEvent( QMouseEvent * me )
 		if( trackAtY != nullptr && trackAtY != this )
 		{
 			// then move us up/down there!
-			if( me->y() < 0 )
+			if (pos.y() < 0)
 			{
 				m_trackContainerView->moveTrackViewUp( this );
 			}
@@ -352,7 +354,7 @@ void TrackView::mouseMoveEvent( QMouseEvent * me )
 	}
 	else if( m_action == Action::Resize )
 	{
-		resizeToHeight(me->y());
+		resizeToHeight(pos.y());
 	}
 
 	if( height() < DEFAULT_TRACK_HEIGHT )
@@ -393,7 +395,9 @@ void TrackView::wheelEvent(QWheelEvent* we)
 	{
 		resizeToHeight(height() + stepSize * direction);
 		we->accept();
+		return;
 	}
+	we->ignore();
 }
 
 

src/gui/widgets/ComboBox.cpp

@@ -33,6 +33,7 @@
 
 #include "CaptionMenu.h"
 #include "FontHelper.h"
+#include "DeprecationHelper.h"
 
 #define QT_SUPPORTS_WIDGET_SCREEN (QT_VERSION >= QT_VERSION_CHECK(5,14,0))
 #if !QT_SUPPORTS_WIDGET_SCREEN
@@ -105,9 +106,11 @@ void ComboBox::mousePressEvent( QMouseEvent* event )
 		return;
 	}
 
+	const auto pos = position(event);
+
 	if( event->button() == Qt::LeftButton && ! ( event->modifiers() & Qt::ControlModifier ) )
 	{
-		if( event->x() > width() - CB_ARROW_BTN_WIDTH )
+		if (pos.x() > width() - CB_ARROW_BTN_WIDTH)
 		{
 			m_pressed = true;
 			update();

src/gui/widgets/Fader.cpp

@@ -54,6 +54,7 @@
 #include "lmms_math.h"
 #include "CaptionMenu.h"
 #include "ConfigManager.h"
+#include "DeprecationHelper.h"
 #include "KeyboardShortcuts.h"
 #include "SimpleTextFloat.h"
 
@@ -172,7 +173,7 @@ void Fader::contextMenuEvent(QContextMenuEvent* ev)
 
 void Fader::mouseMoveEvent(QMouseEvent* mouseEvent)
 {
-	const int localY = mouseEvent->y();
+	const int localY = position(mouseEvent).y();
 
 	setVolumeByLocalPixelValue(localY);
 
@@ -186,6 +187,8 @@ void Fader::mouseMoveEvent(QMouseEvent* mouseEvent)
 
 void Fader::mousePressEvent(QMouseEvent* mouseEvent)
 {
+	const auto pos = position(mouseEvent);
+
 	if (mouseEvent->button() == Qt::LeftButton &&
 			!(mouseEvent->modifiers() & KBD_COPY_MODIFIER))
 	{
@@ -196,7 +199,7 @@ void Fader::mousePressEvent(QMouseEvent* mouseEvent)
 			thisModel->saveJournallingState(false);
 		}
 
-		const int localY = mouseEvent->y();
+		const int localY = pos.y();
 		const auto knobLowerPosY = calculateKnobPosYFromModel();
 		const auto knobUpperPosY = knobLowerPosY - m_knobSize.height();
 

src/gui/widgets/FloatModelEditorBase.cpp

@@ -30,6 +30,7 @@
 #include <QPainter>
 
 #include "lmms_math.h"
+#include "DeprecationHelper.h"
 #include "CaptionMenu.h"
 #include "ControllerConnection.h"
 #include "GuiApplication.h"
@@ -166,8 +167,7 @@ void FloatModelEditorBase::mousePressEvent(QMouseEvent * me)
 			thisModel->saveJournallingState(false);
 		}
 
-		const QPoint & p = me->pos();
-		m_lastMousePos = p;
+		m_lastMousePos = position(me);
 		m_leftOver = 0.0f;
 
 		emit sliderPressed();
@@ -196,13 +196,15 @@ void FloatModelEditorBase::mousePressEvent(QMouseEvent * me)
 
 void FloatModelEditorBase::mouseMoveEvent(QMouseEvent * me)
 {
-	if (m_buttonPressed && me->pos() != m_lastMousePos)
+	const auto pos = position(me);
+
+	if (m_buttonPressed && pos != m_lastMousePos)
 	{
 		// knob position is changed depending on last mouse position
-		setPosition(me->pos() - m_lastMousePos);
+		setPosition(pos - m_lastMousePos);
 		emit sliderMoved(model()->value());
 		// original position for next time is current position
-		m_lastMousePos = me->pos();
+		m_lastMousePos = pos;
 	}
 	s_textFloat->setText(displayValue());
 	s_textFloat->show();
@@ -229,8 +231,11 @@ void FloatModelEditorBase::mouseReleaseEvent(QMouseEvent* event)
 	s_textFloat->hide();
 }
 
-
-void FloatModelEditorBase::enterEvent(QEvent *event)
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+void FloatModelEditorBase::enterEvent(QEnterEvent*)
+#else
+void FloatModelEditorBase::enterEvent(QEvent*)
+#endif
 {
 	showTextFloat(700, 2000);
 }

src/gui/widgets/Graph.cpp

@@ -26,6 +26,7 @@
 #include <QPainter>
 
 #include "Graph.h"
+#include "DeprecationHelper.h"
 #include "SampleLoader.h"
 #include "StringPairDrag.h"
 #include "Oscillator.h"
@@ -99,9 +100,11 @@ void graph::loadSampleFromFile( const QString & _filename )
 
 void Graph::mouseMoveEvent ( QMouseEvent * _me )
 {
+	const auto pos = position(_me);
+
 	// get position
-	int x = _me->x();
-	int y = _me->y();
+	int x = pos.x();
+	int y = pos.y();
 
 /*	static bool skip = false;
 
@@ -146,13 +149,15 @@ void Graph::mouseMoveEvent ( QMouseEvent * _me )
 
 void Graph::mousePressEvent( QMouseEvent * _me )
 {
+	const auto pos = position(_me);
+
 	if( _me->button() == Qt::LeftButton )
 	{
 		if ( !( _me->modifiers() & Qt::ShiftModifier ) )
 		{
 			// get position
-			int x = _me->x();
-			int y = _me->y();
+			int x = pos.x();
+			int y = pos.y();
 
 			changeSampleAt( x, y );
 
@@ -165,8 +170,8 @@ void Graph::mousePressEvent( QMouseEvent * _me )
 		{
 			//when shift-clicking, draw a line from last position to current
 			//position
-			int x = _me->x();
-			int y = _me->y();
+			int x = pos.x();
+			int y = pos.y();
 
 			drawLineAt( x, y, m_lastCursorX );
 

src/gui/widgets/GroupBox.cpp

@@ -26,6 +26,7 @@
 #include <QPainter>
 
 #include "GroupBox.h"
+#include "DeprecationHelper.h"
 #include "embed.h"
 #include "FontHelper.h"
 
@@ -81,7 +82,9 @@ void GroupBox::setLedButtonShown(bool value)
 
 void GroupBox::mousePressEvent( QMouseEvent * _me )
 {
-	if (ledButtonShown() && _me->y() > 1 && _me->y() < 13 && _me->button() == Qt::LeftButton)
+	const auto pos = position(_me);
+
+	if (ledButtonShown() && pos.y() > 1 && pos.y() < 13 && _me->button() == Qt::LeftButton)
 	{
 		model()->setValue(!model()->value());
 	}

src/gui/widgets/LcdFloatSpinBox.cpp

@@ -136,15 +136,17 @@ void LcdFloatSpinBox::contextMenuEvent(QContextMenuEvent* event)
 
 void LcdFloatSpinBox::mousePressEvent(QMouseEvent* event)
 {
+	const auto pos = position(event);
+
 	// switch between integer and fractional step based on cursor position
-	m_intStep = event->x() < m_wholeDisplay.width();
+	m_intStep = pos.x() < m_wholeDisplay.width();
 
 	if (event->button() == Qt::LeftButton &&
 		!(event->modifiers() & KBD_COPY_MODIFIER) &&
-		event->y() < m_wholeDisplay.cellHeight() + 2)
+		pos.y() < m_wholeDisplay.cellHeight() + 2)
 	{
 		m_mouseMoving = true;
-		m_origMousePos = event->globalPos();
+		m_origMousePos = globalPosition(event);
 
 		AutomatableModel *thisModel = model();
 		if (thisModel)
@@ -164,13 +166,14 @@ void LcdFloatSpinBox::mouseMoveEvent(QMouseEvent* event)
 {
 	if (m_mouseMoving)
 	{
-		int dy = event->globalY() - m_origMousePos.y();
+		const auto globalPos = globalPosition(event);
+		int dy = globalPos.y() - m_origMousePos.y();
 		if (getGUI()->mainWindow()->isShiftPressed()) { dy = qBound(-4, dy/4, 4); }
 		if (dy > 1 || dy < -1)
 		{
 			model()->setValue(model()->value() - dy / 2 * getStep());
 			emit manualChange();
-			m_origMousePos = event->globalPos();
+			m_origMousePos = globalPos;
 		}
 	}
 }

src/gui/widgets/LcdSpinBox.cpp

@@ -30,6 +30,7 @@
 #include "LcdSpinBox.h"
 #include "KeyboardShortcuts.h"
 #include "CaptionMenu.h"
+#include "DeprecationHelper.h"
 
 
 namespace lmms::gui
@@ -79,12 +80,14 @@ void LcdSpinBox::contextMenuEvent(QContextMenuEvent* event)
 
 void LcdSpinBox::mousePressEvent( QMouseEvent* event )
 {
-	if( event->button() == Qt::LeftButton &&
-		! (event->modifiers() & KBD_COPY_MODIFIER) &&
-						event->y() < cellHeight() + 2  )
+	const auto pos = position(event);
+
+	if (event->button() == Qt::LeftButton
+		&& !(event->modifiers() & KBD_COPY_MODIFIER)
+		&& pos.y() < cellHeight() + 2)
 	{
 		m_mouseMoving = true;
-		m_lastMousePos = event->globalPos();
+		m_lastMousePos = globalPosition(event);
 
 		AutomatableModel *thisModel = model();
 		if( thisModel )
@@ -106,7 +109,8 @@ void LcdSpinBox::mouseMoveEvent( QMouseEvent* event )
 {
 	if( m_mouseMoving )
 	{
-		int dy = event->globalY() - m_lastMousePos.y();
+		const auto globalPos = globalPosition(event);
+		int dy = globalPos.y() - m_lastMousePos.y();
 		if( dy )
 		{
 			auto fdy = static_cast<float>(dy);
@@ -119,7 +123,7 @@ void LcdSpinBox::mouseMoveEvent( QMouseEvent* event )
 			m_remainder = floatValNotRounded - floatValRounded;
 			model()->setValue( floatValRounded );
 			emit manualChange();
-			m_lastMousePos = event->globalPos();
+			m_lastMousePos = globalPos;
 		}
 	}
 }

src/gui/widgets/SimpleTextFloat.cpp

@@ -39,7 +39,7 @@ SimpleTextFloat::SimpleTextFloat() :
 	QWidget(getGUI()->mainWindow(), Qt::ToolTip)
 {
 	QHBoxLayout * layout = new QHBoxLayout(this);
-	layout->setMargin(3);
+	layout->setContentsMargins(3, 3, 3, 3);
 	setLayout(layout);
 
 	m_textLabel = new QLabel(this);

src/gui/widgets/TabWidget.cpp

@@ -123,10 +123,10 @@ void TabWidget::setActiveTab(int idx)
 
 
 // Return the index of the tab at position "pos"
-int TabWidget::findTabAtPos(const QPoint* pos)
+int TabWidget::findTabAtPos(const QPoint& pos)
 {
 
-	if (pos->y() > 1 && pos->y() < m_tabbarHeight - 1)
+	if (pos.y() > 1 && pos.y() < m_tabbarHeight - 1)
 	{
 		int cx = ((m_caption == "") ? 4 : 14) + horizontalAdvance(fontMetrics(), m_caption);
 
@@ -134,7 +134,7 @@ int TabWidget::findTabAtPos(const QPoint* pos)
 		{
 			int const currentWidgetWidth = it->nwidth;
 
-			if (pos->x() >= cx && pos->x() <= cx + currentWidgetWidth)
+			if (pos.x() >= cx && pos.x() <= cx + currentWidgetWidth)
 			{
 				return(it.key());
 			}
@@ -155,7 +155,7 @@ bool TabWidget::event(QEvent* event)
 	{
 		auto helpEvent = static_cast<QHelpEvent*>(event);
 
-		int idx = findTabAtPos(& helpEvent->pos());
+		int idx = findTabAtPos(helpEvent->pos());
 
 		if (idx != -1)
 		{
@@ -180,10 +180,8 @@ bool TabWidget::event(QEvent* event)
 // Activate tab when clicked
 void TabWidget::mousePressEvent(QMouseEvent* me)
 {
-
 	// Find index of tab that has been clicked
-	QPoint pos = me->pos();
-	int idx = findTabAtPos(&pos);
+	const int idx = findTabAtPos(position(me));
 
 	// When found, activate tab that has been clicked
 	if (idx != -1)