Qt: Add a saturateCast template

src/platform/qt/DisplayGL.cpp

@@ -60,6 +60,7 @@ typedef struct _XDisplay Display;
 #endif
 
 #include "OpenGLBug.h"
+#include "utils.h"
 
 using namespace QGBA;
 
@@ -1003,8 +1004,8 @@ VideoShader* PainterGL::shaders() {
 QSize PainterGL::contentSize() const {
 	unsigned width, height;
 	VideoBackendGetFrameSize(m_backend, &width, &height);
-	return {static_cast<int>(width > static_cast<unsigned>(INT_MAX) ? INT_MAX : width),
-	        static_cast<int>(height > static_cast<unsigned>(INT_MAX) ? INT_MAX : height)};
+	return {saturateCast<int>(width),
+	        saturateCast<int>(height)};
 }
 
 int PainterGL::glTex() {

src/platform/qt/DisplayQt.cpp

@@ -181,7 +181,7 @@ void DisplayQt::redoBounds() {
 QSize DisplayQt::contentSize() const {
 	unsigned w, h;
 	VideoBackendGetFrameSize(&m_backend, &w, &h);
-	return {w, h};
+	return {saturateCast<int>(w), saturateCast<int>(h)};
 }
 
 void DisplayQt::init(struct VideoBackend*, WHandle) {

src/platform/qt/scripting/ScriptingTextBuffer.cpp

@@ -6,6 +6,7 @@
 #include "ScriptingTextBuffer.h"
 
 #include "GBAApp.h"
+#include "utils.h"
 
 #include <QMutexLocker>
 #include <QPlainTextDocumentLayout>
@@ -205,13 +206,8 @@ void ScriptingTextBuffer::setSize(struct mScriptTextBuffer* buffer, uint32_t col
 
 void ScriptingTextBuffer::moveCursor(struct mScriptTextBuffer* buffer, uint32_t x, uint32_t y) {
 	ScriptingTextBuffer* self = static_cast<ScriptingTextBuffer::ScriptingBufferShim*>(buffer)->p;
-	if (x > INT_MAX) {
-		x = INT_MAX;
-	}
-	if (y > INT_MAX) {
-		y = INT_MAX;
-	}
-	QMetaObject::invokeMethod(self, "moveCursor", Q_ARG(QPoint, QPoint(x, y)));
+	QPoint point(saturateCast<int>(x), saturateCast<int>(y));
+	QMetaObject::invokeMethod(self, "moveCursor", Q_ARG(QPoint, point));
 }
 
 void ScriptingTextBuffer::advance(struct mScriptTextBuffer* buffer, int32_t adv) {

src/platform/qt/utils.h

@@ -72,6 +72,46 @@ constexpr const T& clamp(const T& v, const T& lo, const T& hi) {
 }
 #endif
 
+template<typename T, typename U>
+constexpr T saturateCast(U value) {
+	if (std::numeric_limits<T>::is_signed == std::numeric_limits<T>::is_signed) {
+		if (value > std::numeric_limits<T>::max()) {
+			return std::numeric_limits<T>::max();
+		}
+		if (value < std::numeric_limits<T>::min()) {
+			return std::numeric_limits<T>::min();
+		}
+	} else if (std::numeric_limits<T>::is_signed) {
+		if (value > static_cast<uintmax_t>(std::numeric_limits<T>::max())) {
+			std::numeric_limits<T>::max();
+		}
+	} else {
+		if (value < 0) {
+			return 0;
+		}
+		if (static_cast<uintmax_t>(value) > std::numeric_limits<T>::max()) {
+			std::numeric_limits<T>::max();
+		}
+	}
+	return static_cast<T>(value);
+}
+
+template<>
+constexpr unsigned saturateCast<unsigned, int>(int value) {
+	if (value < 0) {
+		return 0;
+	}
+	return static_cast<unsigned>(value);
+}
+
+template<>
+constexpr int saturateCast<int, unsigned>(unsigned value) {
+	if (value > static_cast<unsigned>(std::numeric_limits<int>::max())) {
+		return std::numeric_limits<int>::max();
+	}
+	return static_cast<int>(value);
+}
+
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