Merge pull request #821 from TomHarte/QtThreading

Qt issue mega ticket

ClockReceiver/VSyncPredictor.hpp

@@ -63,6 +63,13 @@ class VSyncPredictor {
 			frame_duration_ = Nanos(1'000'000'000.0f / rate);
 		}
 
+		/*!
+			@returns The time this class currently believes a whole frame occupies.
+		*/
+		Time::Nanos frame_duration() {
+			return frame_duration_;
+		}
+
 		/*!
 			Adds a record of how much jitter was experienced in scheduling; these values will be
 			factored into the @c suggested_draw_time if supplied.
@@ -87,15 +94,13 @@ class VSyncPredictor {
 			(if those figures are being supplied).
 		*/
 		Nanos suggested_draw_time() {
-			const auto mean = redraw_period_.mean() - timer_jitter_.mean() - vsync_jitter_.mean();
+			const auto mean = redraw_period_.mean() + timer_jitter_.mean() + vsync_jitter_.mean();
 			const auto variance = redraw_period_.variance() + timer_jitter_.variance() + vsync_jitter_.variance();
 
 			// Permit three standard deviations from the mean, to cover 99.9% of cases.
-			const auto period = mean - Nanos(3.0f * sqrt(float(variance)));
+			const auto period = mean + Nanos(3.0f * sqrt(float(variance)));
 
-			assert(abs(period) < 10'000'000'000);
-
-			return last_vsync_ + period;
+			return last_vsync_ + frame_duration_ - period;
 		}
 
 	private:
@@ -109,7 +114,6 @@ class VSyncPredictor {
 				}
 
 				void post(Time::Nanos value) {
-					assert(abs(value) < 10'000'000'000);	// 10 seconds is a very liberal maximum.
 					sum_ -= history_[write_pointer_];
 					sum_ += value;
 					history_[write_pointer_] = value;

OSBindings/Qt/mainwindow.cpp

@@ -45,7 +45,9 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent) {
 
 MainWindow::MainWindow(const QString &fileName) {
 	init();
-	launchFile(fileName);
+	if(!launchFile(fileName)) {
+		setUIPhase(UIPhase::SelectingMachine);
+	}
 }
 
 void MainWindow::deleteMachine() {
@@ -210,11 +212,17 @@ void MainWindow::insertFile(const QString &fileName) {
 	mediaTarget->insert_media(media);
 }
 
-void MainWindow::launchFile(const QString &fileName) {
+bool MainWindow::launchFile(const QString &fileName) {
 	targets = Analyser::Static::GetTargets(fileName.toStdString());
 	if(!targets.empty()) {
 		openFileName = QFileInfo(fileName).fileName();
 		launchMachine();
+		return true;
+	} else {
+		QMessageBox msgBox;
+		msgBox.setText("Unable to open file: " + fileName);
+		msgBox.exec();
+		return false;
 	}
 }
 
@@ -707,6 +715,7 @@ void MainWindow::dropEvent(QDropEvent* event) {
 			bool foundROM = false;
 			const auto appDataLocation = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation).toStdString();
 
+			QString unusedRoms;
 			for(const auto &url: event->mimeData()->urls()) {
 				const char *const name = url.toLocalFile().toUtf8();
 				FILE *const file = fopen(name, "rb");
@@ -716,6 +725,7 @@ void MainWindow::dropEvent(QDropEvent* event) {
 				CRC::CRC32 generator;
 				const uint32_t crc = generator.compute_crc(*contents);
 
+				bool wasUsed = false;
 				for(const auto &rom: missingRoms) {
 					if(std::find(rom.crc32s.begin(), rom.crc32s.end(), crc) != rom.crc32s.end()) {
 						foundROM = true;
@@ -731,10 +741,22 @@ void MainWindow::dropEvent(QDropEvent* event) {
 						FILE *const target = fopen(destination.c_str(), "wb");
 						fwrite(contents->data(), 1, contents->size(), target);
 						fclose(target);
+
+						wasUsed = true;
 					}
 				}
+
+				if(!wasUsed) {
+					if(!unusedRoms.isEmpty()) unusedRoms += ", ";
+					unusedRoms += url.fileName();
+				}
 			}
 
+			if(!unusedRoms.isEmpty()) {
+				QMessageBox msgBox;
+				msgBox.setText("Couldn't identify ROMs: " + unusedRoms);
+				msgBox.exec();
+			}
 			if(foundROM) launchMachine();
 		} break;
 	}
@@ -1338,24 +1360,25 @@ void MainWindow::addActivityObserver() {
 }
 
 void MainWindow::register_led(const std::string &name) {
+	std::lock_guard guard(ledStatusesLock);
 	ledStatuses[name] = false;
-	updateStatusBarText();
+	QMetaObject::invokeMethod(this, "updateStatusBarText");
 }
 
 void MainWindow::set_led_status(const std::string &name, bool isLit) {
+	std::lock_guard guard(ledStatusesLock);
 	ledStatuses[name] = isLit;
-	updateStatusBarText();	// Assumption here: Qt's attempt at automatic thread confinement will work here.
+	QMetaObject::invokeMethod(this, "updateStatusBarText");
 }
 
 void MainWindow::updateStatusBarText() {
 	QString fullText;
-	bool isFirst = true;
+	std::lock_guard guard(ledStatusesLock);
 	for(const auto &pair: ledStatuses) {
-		if(!isFirst) fullText += " | ";
+		if(!fullText.isEmpty()) fullText += " | ";
 		fullText += QString::fromStdString(pair.first);
 		fullText += " ";
 		fullText += pair.second ? "■" : "□";
-		isFirst = false;
 	}
 	statusBar()->showMessage(fullText);
 }

OSBindings/Qt/mainwindow.h

@@ -5,6 +5,7 @@
 #include <QMainWindow>
 
 #include <memory>
+#include <mutex>
 #include <optional>
 
 #include "audiobuffer.h"
@@ -80,6 +81,7 @@ class MainWindow : public QMainWindow, public Outputs::Speaker::Speaker::Delegat
 
 	private slots:
 		void startMachine();
+		void updateStatusBarText();
 
 	private:
 		void start_appleII();
@@ -100,7 +102,7 @@ class MainWindow : public QMainWindow, public Outputs::Speaker::Speaker::Delegat
 		QAction *insertAction = nullptr;
 		void insertFile(const QString &fileName);
 
-		void launchFile(const QString &fileName);
+		bool launchFile(const QString &fileName);
 		void launchTarget(std::unique_ptr<Analyser::Static::Target> &&);
 
 		void restoreSelections();
@@ -144,9 +146,11 @@ class MainWindow : public QMainWindow, public Outputs::Speaker::Speaker::Delegat
 
 		void register_led(const std::string &) override;
 		void set_led_status(const std::string &, bool) override;
+
+		std::recursive_mutex ledStatusesLock;
 		std::map<std::string, bool> ledStatuses;
+
 		void addActivityObserver();
-		void updateStatusBarText();
 };
 
 #endif // MAINWINDOW_H

OSBindings/Qt/scantargetwidget.cpp

@@ -86,7 +86,7 @@ void ScanTargetWidget::vsync() {
 	const auto time_now = Time::nanos_now();
 	requestedRedrawTime = vsyncPredictor.suggested_draw_time();
 	const auto delay_time = (requestedRedrawTime - time_now) / 1'000'000;
-	if(delay_time > 0) {
+	if(delay_time > 0 && delay_time < vsyncPredictor.frame_duration()) {
 		QTimer::singleShot(delay_time, this, SLOT(repaint()));
 	} else {
 		requestedRedrawTime = 0;