Qt: Add option to lock the maximum frame size (closes #1493)

CHANGES

@@ -1,5 +1,6 @@
 0.11.0: (Future)
 Features:
+ - New option to lock the maximum frame size
  - Scripting: New `input` API for getting raw keyboard/mouse/controller state
  - Scripting: New `storage` API for saving data for a script, e.g. settings
  - Scripting: Debugger integration to allow for breakpoints and watchpoints

include/mgba/feature/proxy-backend.h

@@ -38,6 +38,8 @@ union mVideoBackendCommandData {
 	struct {
 		unsigned width;
 		unsigned height;
+		unsigned maxW;
+		unsigned maxH;
 	} u;
 	const void* image;
 };

include/mgba/feature/video-backend.h

@@ -48,7 +48,7 @@ struct VideoBackend {
 	void (*layerDimensions)(const struct VideoBackend*, enum VideoLayer, struct mRectangle*);
 	void (*swap)(struct VideoBackend*);
 	void (*clear)(struct VideoBackend*);
-	void (*contextResized)(struct VideoBackend*, unsigned w, unsigned h);
+	void (*contextResized)(struct VideoBackend*, unsigned w, unsigned h, unsigned maxW, unsigned maxH);
 	void (*setImageSize)(struct VideoBackend*, enum VideoLayer, int w, int h);
 	void (*imageSize)(struct VideoBackend*, enum VideoLayer, int* w, int* h);
 	void (*setImage)(struct VideoBackend*, enum VideoLayer, const void* frame);

src/feature/proxy-backend.c

@@ -61,7 +61,7 @@ static void _mVideoProxyBackendClear(struct VideoBackend* v) {
 	mVideoProxyBackendSubmit(proxy, &cmd, NULL);
 }
 
-static void _mVideoProxyBackendContextResized(struct VideoBackend* v, unsigned w, unsigned h) {
+static void _mVideoProxyBackendContextResized(struct VideoBackend* v, unsigned w, unsigned h, unsigned maxW, unsigned maxH) {
 	struct mVideoProxyBackend* proxy = (struct mVideoProxyBackend*) v;
 	struct mVideoBackendCommand cmd = {
 		.cmd = mVB_CMD_CONTEXT_RESIZED,
@@ -69,6 +69,8 @@ static void _mVideoProxyBackendContextResized(struct VideoBackend* v, unsigned w
 			.u = {
 				.width = w,
 				.height = h,
+				.maxW = maxW,
+				.maxH = maxH,
 			}
 		}
 	};
@@ -139,8 +141,8 @@ void mVideoProxyBackendInit(struct mVideoProxyBackend* proxy, struct VideoBacken
 	proxy->d.drawFrame = _mVideoProxyBackendDrawFrame;
 	proxy->backend = backend;
 
-	RingFIFOInit(&proxy->in, 0x400);
-	RingFIFOInit(&proxy->out, 0x400);
+	RingFIFOInit(&proxy->in, sizeof(union mVideoBackendCommandData) * 0x80);
+	RingFIFOInit(&proxy->out, sizeof(union mVideoBackendCommandData) * 0x80);
 	MutexInit(&proxy->inLock);
 	MutexInit(&proxy->outLock);
 	ConditionInit(&proxy->inWait);
@@ -209,7 +211,7 @@ bool mVideoProxyBackendRun(struct mVideoProxyBackend* proxy, bool block) {
 				proxy->backend->clear(proxy->backend);
 				break;
 			case mVB_CMD_CONTEXT_RESIZED:
-				proxy->backend->contextResized(proxy->backend, cmd.data.u.width, cmd.data.u.height);
+				proxy->backend->contextResized(proxy->backend, cmd.data.u.width, cmd.data.u.height, cmd.data.u.maxW, cmd.data.u.maxH);
 				break;
 			case mVB_CMD_SET_IMAGE_SIZE:
 				proxy->backend->setImageSize(proxy->backend, cmd.layer, cmd.data.s.width, cmd.data.s.height);

src/platform/opengl/gl.c

@@ -103,20 +103,29 @@ static void mGLContextDeinit(struct VideoBackend* v) {
 	glDeleteTextures(VIDEO_LAYER_MAX, context->layers);
 }
 
-static void mGLContextResized(struct VideoBackend* v, unsigned w, unsigned h) {
+static void mGLContextResized(struct VideoBackend* v, unsigned w, unsigned h, unsigned maxW, unsigned maxH) {
 	unsigned drawW = w;
 	unsigned drawH = h;
 
-	unsigned maxW;
-	unsigned maxH;
-	VideoBackendGetFrameSize(v, &maxW, &maxH);
+
+	if (maxW && drawW > maxW) {
+		drawW = maxW;
+	}
+
+	if (maxH && drawH > maxH) {
+		drawH = maxH;
+	}
+
+	unsigned lockW;
+	unsigned lockH;
+	VideoBackendGetFrameSize(v, &lockW, &lockH);
 
 	if (v->lockAspectRatio) {
-		lockAspectRatioUInt(maxW, maxH, &drawW, &drawH);
+		lockAspectRatioUInt(lockW, lockH, &drawW, &drawH);
 	}
 	if (v->lockIntegerScaling) {
-		lockIntegerRatioUInt(maxW, &drawW);
-		lockIntegerRatioUInt(maxH, &drawH);
+		lockIntegerRatioUInt(lockW, &drawW);
+		lockIntegerRatioUInt(lockH, &drawH);
 	}
 	glMatrixMode(GL_MODELVIEW);
 	glLoadIdentity();

src/platform/opengl/gles2.c

@@ -271,20 +271,28 @@ static void mGLES2ContextDeinit(struct VideoBackend* v) {
 	free(context->initialShader.uniforms);
 }
 
-static void mGLES2ContextResized(struct VideoBackend* v, unsigned w, unsigned h) {
+static void mGLES2ContextResized(struct VideoBackend* v, unsigned w, unsigned h, unsigned maxW, unsigned maxH) {
 	struct mGLES2Context* context = (struct mGLES2Context*) v;
 	unsigned drawW = w;
 	unsigned drawH = h;
 
-	unsigned maxW = context->width;
-	unsigned maxH = context->height;
+	if (maxW && drawW > maxW) {
+		drawW = maxW;
+	}
+
+	if (maxH && drawH > maxH) {
+		drawH = maxH;
+	}
+
+	unsigned lockW = context->width;
+	unsigned lockH = context->height;
 
 	if (v->lockAspectRatio) {
-		lockAspectRatioUInt(maxW, maxH, &drawW, &drawH);
+		lockAspectRatioUInt(lockW, lockH, &drawW, &drawH);
 	}
 	if (v->lockIntegerScaling) {
-		lockIntegerRatioUInt(maxW, &drawW);
-		lockIntegerRatioUInt(maxH, &drawH);
+		lockIntegerRatioUInt(lockW, &drawW);
+		lockIntegerRatioUInt(lockH, &drawH);
 	}
 	size_t n;
 	for (n = 0; n < context->nShaders; ++n) {

src/platform/qt/Display.h

@@ -57,6 +57,7 @@ public:
 	virtual void setVideoScale(int) {}
 	virtual void setBackgroundImage(const QImage&) = 0;
 	virtual QSize contentSize() const = 0;
+	virtual void setMaximumSize(const QSize& size) = 0;
 
 	virtual void setVideoProxy(std::shared_ptr<VideoProxy> proxy) { m_videoProxy = std::move(proxy); }
 	std::shared_ptr<VideoProxy> videoProxy() { return m_videoProxy; }
@@ -105,6 +106,7 @@ private:
 	bool m_filter = false;
 	QTimer m_mouseTimer;
 	std::shared_ptr<VideoProxy> m_videoProxy;
+	QSize m_maxSize;
 };
 
 }

src/platform/qt/DisplayGL.cpp

@@ -524,6 +524,10 @@ int DisplayGL::framebufferHandle() {
 	return m_painter->glTex();
 }
 
+void DisplayGL::setMaximumSize(const QSize& size) {
+	QMetaObject::invokeMethod(m_painter.get(), "setMaximumSize", Q_ARG(const QSize&, size));
+}
+
 PainterGL::PainterGL(QWindow* window, mGLWidget* widget, const QSurfaceFormat& format)
 	: m_window(window)
 	, m_format(format)
@@ -720,6 +724,11 @@ void PainterGL::resize(const QSize& size) {
 	}
 }
 
+void PainterGL::setMaximumSize(const QSize& size) {
+	m_maxSize = size;
+	resizeContext();
+}
+
 void PainterGL::lockAspectRatio(bool lock) {
 	m_backend->lockAspectRatio = lock;
 	resize(m_size);
@@ -911,7 +920,11 @@ void PainterGL::unpause() {
 
 void PainterGL::performDraw() {
 	float r = m_window->devicePixelRatio();
-	m_backend->contextResized(m_backend, m_size.width() * r, m_size.height() * r);
+	QSize maxSize = m_maxSize;
+	if (!maxSize.isValid()) {
+		maxSize = QSize(0, 0);
+	}
+	m_backend->contextResized(m_backend, m_size.width() * r, m_size.height() * r, maxSize.width() * r, maxSize.height() * r);
 	if (m_buffer) {
 		m_backend->setImage(m_backend, VIDEO_LAYER_IMAGE, m_buffer);
 	}

src/platform/qt/DisplayGL.h

@@ -95,6 +95,7 @@ public:
 	void setVideoProxy(std::shared_ptr<VideoProxy>) override;
 	int framebufferHandle() override;
 	QSize contentSize() const override { return m_cachedContentSize; }
+	void setMaximumSize(const QSize& size) override;
 
 	static bool highestCompatible(QSurfaceFormat&);
 	static bool supportsFormat(const QSurfaceFormat&);
@@ -172,6 +173,7 @@ public slots:
 	void pause();
 	void unpause();
 	void resize(const QSize& size);
+	void setMaximumSize(const QSize& size);
 	void lockAspectRatio(bool lock);
 	void lockIntegerScaling(bool lock);
 	void interframeBlending(bool enable);
@@ -230,6 +232,7 @@ private:
 	VideoBackend* m_backend = nullptr;
 	QSize m_size;
 	QSize m_dims;
+	QSize m_maxSize;
 	MessagePainter* m_messagePainter = nullptr;
 	QElapsedTimer m_delayTimer;
 	std::shared_ptr<VideoProxy> m_videoProxy;

src/platform/qt/DisplayQt.cpp

@@ -134,7 +134,20 @@ void DisplayQt::paintEvent(QPaintEvent*) {
 	if (!drawSize.isValid() || drawSize.width() < 1 || drawSize.height() < 1) {
 		return;
 	}
-	QRect full(clampSize(contentSize(), size(), isAspectRatioLocked(), isIntegerScalingLocked()));
+	QSize usedSize = size();
+	QPoint screenOrigin(0, 0);
+	if (m_maxSize.isValid()) {
+		if (m_maxSize.width() < usedSize.width()) {
+			screenOrigin.setX((usedSize.width() - m_maxSize.width()) / 2);
+			usedSize.setWidth(m_maxSize.width());
+		}
+		if (m_maxSize.height() < usedSize.height()) {
+			screenOrigin.setY((usedSize.height() - m_maxSize.height()) / 2);
+			usedSize.setHeight(m_maxSize.height());
+		}
+	}
+	QRect full(clampSize(contentSize(), usedSize, isAspectRatioLocked(), isIntegerScalingLocked()));
+	full.translate(screenOrigin);
 	painter.save();
 	painter.translate(full.topLeft());
 	painter.scale(full.width() / static_cast<qreal>(frame.width), full.height() / static_cast<qreal>(frame.height));
@@ -220,7 +233,7 @@ void DisplayQt::swap(struct VideoBackend*) {
 void DisplayQt::clear(struct VideoBackend*) {
 }
 
-void DisplayQt::contextResized(struct VideoBackend*, unsigned, unsigned) {
+void DisplayQt::contextResized(struct VideoBackend*, unsigned, unsigned, unsigned, unsigned) {
 }
 
 void DisplayQt::setImageSize(struct VideoBackend* v, enum VideoLayer layer, int w, int h) {

src/platform/qt/DisplayQt.h

@@ -27,6 +27,8 @@ public:
 	VideoShader* shaders() override { return nullptr; }
 	QSize contentSize() const override;
 	VideoBackend* videoBackend() override { return &m_backend; }
+	void setMaximumSize(const QSize& size) override { m_maxSize = size; }
+
 
 public slots:
 	void stopDrawing() override;
@@ -56,7 +58,7 @@ private:
 	static void layerDimensions(const struct VideoBackend*, enum VideoLayer, struct mRectangle*);
 	static void swap(struct VideoBackend*);
 	static void clear(struct VideoBackend*);
-	static void contextResized(struct VideoBackend*, unsigned w, unsigned h);
+	static void contextResized(struct VideoBackend*, unsigned w, unsigned h, unsigned maxW, unsigned maxH);
 	static void setImageSize(struct VideoBackend*, enum VideoLayer, int w, int h);
 	static void imageSize(struct VideoBackend*, enum VideoLayer, int* w, int* h);
 	static void setImage(struct VideoBackend*, enum VideoLayer, const void* frame);
@@ -69,6 +71,7 @@ private:
 	int m_width = -1;
 	int m_height = -1;
 	QImage m_oldBacking{nullptr};
+	QSize m_maxSize;
 	std::shared_ptr<CoreController> m_context = nullptr;
 };
 

src/platform/qt/Window.cpp

@@ -252,6 +252,9 @@ void Window::argumentsPassed() {
 
 void Window::resizeFrame(const QSize& size) {
 	QSize newSize(size);
+	if (!m_config->getOption("lockFrameSize").toInt()) {
+		m_savedSize = size;
+	}
 	if (windowHandle()) {
 		QRect geom = windowHandle()->screen()->availableGeometry();
 		if (newSize.width() > geom.width()) {
@@ -1522,7 +1525,10 @@ void Window::setupMenu(QMenuBar* menubar) {
 	for (int i = 1; i <= 8; ++i) {
 		auto setSize = m_actions.addAction(tr("%1×").arg(QString::number(i)), QString("frame.%1x").arg(QString::number(i)), [this, i]() {
 			auto setSize = m_frameSizes[i];
+			bool lockFrameSize = m_config->getOption("lockFrameSize").toInt();
+			if (!lockFrameSize) {
 				showNormal();
+			}
 #if defined(M_CORE_GBA)
 			QSize minimumSize = QSize(GBA_VIDEO_HORIZONTAL_PIXELS, GBA_VIDEO_VERTICAL_PIXELS);
 #elif defined(M_CORE_GB)
@@ -1538,7 +1544,11 @@ void Window::setupMenu(QMenuBar* menubar) {
 			size *= i;
 			m_savedScale = i;
 			m_config->setOption("scaleMultiplier", i); // TODO: Port to other
+			m_savedSize = size;
 			resizeFrame(size);
+			if (lockFrameSize) {
+				m_display->setMaximumSize(size);
+			}
 			setSize->setActive(true);
 		}, "frame");
 		setSize->setExclusive(true);
@@ -1553,8 +1563,22 @@ void Window::setupMenu(QMenuBar* menubar) {
 #else
 	fullscreenKeys = QKeySequence("Ctrl+F");
 #endif
+	m_actions.addSeparator("frame");
 	m_actions.addAction(tr("Toggle fullscreen"), "fullscreen", this, &Window::toggleFullScreen, "frame", fullscreenKeys);
 
+	ConfigOption* lockFrameSize = m_config->addOption("lockFrameSize");
+	lockFrameSize->addBoolean(tr("&Lock frame size"), &m_actions, "frame");
+	lockFrameSize->connect([this](const QVariant& value) {
+		if (m_display) {
+			if (value.toBool()) {
+				m_display->setMaximumSize(m_display->size());
+			} else {
+				m_display->setMaximumSize({});
+			}
+		}
+	}, this);
+	m_config->updateOption("lockFrameSize");
+
 	ConfigOption* lockAspectRatio = m_config->addOption("lockAspectRatio");
 	lockAspectRatio->addBoolean(tr("Lock aspect ratio"), &m_actions, "av");
 	lockAspectRatio->connect([this](const QVariant& value) {
@@ -2216,6 +2240,11 @@ void Window::setController(CoreController* controller, const QString& fname) {
 void Window::attachDisplay() {
 	m_display->attach(m_controller);
 	connect(m_display.get(), &QGBA::Display::drawingStarted, this, &Window::changeRenderer);
+	if (m_config->getOption("lockFrameSize").toInt()) {
+		m_display->setMaximumSize(m_savedSize);
+	} else {
+		m_display->setMaximumSize({});
+	}
 	m_display->startDrawing(m_controller);
 
 #ifdef ENABLE_SCRIPTING

src/platform/qt/Window.h

@@ -194,6 +194,7 @@ private:
 
 	std::unique_ptr<QGBA::Display> m_display;
 	QSize m_initialSize;
+	QSize m_savedSize;
 	int m_savedScale;
 
 	// TODO: Move these to a new class

src/platform/sdl/gl-common.c

@@ -15,7 +15,7 @@
 #endif
 
 void mSDLGLDoViewport(int w, int h, struct VideoBackend* v) {
-	v->contextResized(v, w, h);
+	v->contextResized(v, w, h, 0, 0);
 	v->clear(v);
 	v->swap(v);
 	v->clear(v);