Qt: Manually toggle swap interval as needed

CMakeLists.txt

@@ -419,6 +419,13 @@ if(BUILD_GL)
 	elseif(UNIX AND NOT APPLE AND TARGET OpenGL::GL)
 		set(OPENGL_LIBRARY OpenGL::GL)
 	endif()
+	if(OpenGL_GLX_FOUND)
+		list(APPEND FEATURES GLX)
+	endif()
+	if(OpenGL_EGL_FOUND)
+		list(APPEND FEATURES EGL)
+		list(APPEND OPENGL_LIBRARY ${OPENGL_egl_LIBRARY})
+	endif()
 endif()
 if(BUILD_GL)
 	list(APPEND FEATURE_SRC ${CMAKE_CURRENT_SOURCE_DIR}/src/platform/opengl/gl.c)

src/platform/qt/Display.cpp

@@ -111,6 +111,7 @@ void QGBA::Display::configure(ConfigController* config) {
 	filter(opts->resampleVideo);
 	config->updateOption("showOSD");
 	config->updateOption("showFrameCounter");
+	config->updateOption("videoSync");
 #if defined(BUILD_GL) || defined(BUILD_GLES2) || defined(BUILD_GLES3)
 	if (opts->shader && supportsShaders()) {
 		struct VDir* shader = VDirOpen(opts->shader);

src/platform/qt/Display.h

@@ -72,6 +72,7 @@ public slots:
 	virtual void showOSDMessages(bool enable);
 	virtual void showFrameCounter(bool enable);
 	virtual void filter(bool filter);
+	virtual void swapInterval(int interval) = 0;
 	virtual void framePosted() = 0;
 	virtual void setShaders(struct VDir*) = 0;
 	virtual void clearShaders() = 0;

src/platform/qt/DisplayGL.cpp

@@ -38,6 +38,21 @@ using QOpenGLFunctions_Baseline = QOpenGLFunctions_3_2_Core;
 #endif
 #endif
 
+#ifdef _WIN32
+#include <windows.h>
+#elif defined(Q_OS_MAC)
+#include <OpenGL/OpenGL.h>
+#endif
+#ifdef USE_GLX
+#define GLX_GLXEXT_PROTOTYPES
+typedef struct _XDisplay Display;
+#include <GL/glx.h>
+#include <GL/glxext.h>
+#endif
+#ifdef USE_EGL
+#include <EGL/egl.h>
+#endif
+
 #ifdef _WIN32
 #define OVERHEAD_NSEC 1000000
 #else
@@ -412,6 +427,10 @@ void DisplayGL::filter(bool filter) {
 	QMetaObject::invokeMethod(m_painter.get(), "filter", Q_ARG(bool, filter));
 }
 
+void DisplayGL::swapInterval(int interval) {
+	QMetaObject::invokeMethod(m_painter.get(), "swapInterval", Q_ARG(int, interval));
+}
+
 void DisplayGL::framePosted() {
 	m_painter->enqueue(m_context->drawContext());
 	QMetaObject::invokeMethod(m_painter.get(), "draw");
@@ -717,6 +736,32 @@ void PainterGL::filter(bool filter) {
 	}
 }
 
+void PainterGL::swapInterval(int interval) {
+	if (!m_started) {
+		return;
+	}
+	m_swapInterval = interval;
+#ifdef Q_OS_WIN
+	wglSwapIntervalEXT(interval);
+#elif defined(Q_OS_MAC)
+	CGLSetParameter(CGLGetCurrentContext(), kCGLCPSwapInterval, &interval);
+#else
+#ifdef USE_GLX
+	if (QGuiApplication::platformName() == "xcb") {
+		::Display* display = glXGetCurrentDisplay();
+		GLXDrawable drawable = glXGetCurrentDrawable();
+		glXSwapIntervalEXT(display, drawable, interval);
+	}
+#endif
+#ifdef USE_EGL
+	if (QGuiApplication::platformName().contains("egl")) {
+		EGLDisplay display = eglGetCurrentDisplay();
+		eglSwapInterval(display, interval);
+	}
+#endif
+#endif
+}
+
 #ifndef GL_DEBUG_OUTPUT_SYNCHRONOUS
 #define GL_DEBUG_OUTPUT_SYNCHRONOUS 0x8242
 #endif
@@ -773,6 +818,9 @@ void PainterGL::draw() {
 		}
 		return;
 	}
+	if (m_swapInterval != !!sync->videoFrameWait) {
+		swapInterval(!!sync->videoFrameWait);
+	}
 	dequeue();
 	bool forceRedraw = true;
 	if (!m_delayTimer.isValid()) {

src/platform/qt/DisplayGL.h

@@ -108,6 +108,7 @@ public slots:
 	void showOSDMessages(bool enable) override;
 	void showFrameCounter(bool enable) override;
 	void filter(bool filter) override;
+	void swapInterval(int interval) override;
 	void framePosted() override;
 	void setShaders(struct VDir*) override;
 	void clearShaders() override;
@@ -182,6 +183,7 @@ public slots:
 	void showOSD(bool enable);
 	void showFrameCounter(bool enable);
 	void filter(bool filter);
+	void swapInterval(int interval);
 	void resizeContext();
 	void updateFramebufferHandle();
 
@@ -240,6 +242,7 @@ private:
 	MessagePainter* m_messagePainter = nullptr;
 	QElapsedTimer m_delayTimer;
 	std::shared_ptr<VideoProxy> m_videoProxy;
+	int m_swapInterval = -1;
 };
 
 }

src/platform/qt/DisplayQt.h

@@ -31,6 +31,7 @@ public slots:
 	void lockAspectRatio(bool lock) override;
 	void lockIntegerScaling(bool lock) override;
 	void interframeBlending(bool enable) override;
+	void swapInterval(int) override {};
 	void filter(bool filter) override;
 	void framePosted() override;
 	void setShaders(struct VDir*) override {}

src/platform/qt/Window.cpp

@@ -1788,7 +1788,14 @@ void Window::setupMenu(QMenuBar* menubar) {
 
 void Window::setupOptions() {
 	ConfigOption* videoSync = m_config->addOption("videoSync");
-	videoSync->connect([this](const QVariant&) {
+	videoSync->connect([this](const QVariant& variant) {
+		if (m_display) {
+			bool ok;
+			int interval = variant.toInt(&ok);
+			if (ok) {
+				m_display->swapInterval(interval);
+			}
+		}
 		reloadConfig();
 	}, this);