Improved error handling

src/offlinemap.cpp

@@ -305,7 +305,7 @@ bool OfflineMap::getImageInfo(const QString &path)
 	}
 
 	if (_imgPath.endsWith("ozf2")) {
-		_ozf.load(_imgPath);
+		if (_ozf.load(_imgPath))
 			_size = _ozf.size();
 	} else {
 		QImageReader img(_imgPath);
@@ -540,9 +540,8 @@ void OfflineMap::unload()
 	}
 }
 
-void OfflineMap::draw(QPainter *painter, const QRectF &rect)
+void OfflineMap::drawTiled(QPainter *painter, const QRectF &rect)
 {
-	if (_tileSize.isValid()) {
 	QPoint tl = QPoint((int)floor(rect.left() / (qreal)_tileSize.width())
 	  * _tileSize.width(), (int)floor(rect.top() / _tileSize.height())
 	  * _tileSize.height());
@@ -552,6 +551,12 @@ void OfflineMap::draw(QPainter *painter, const QRectF &rect)
 		for (int j = 0; j < ceil(s.height() / _tileSize.height()); j++) {
 			int x = tl.x() + i * _tileSize.width();
 			int y = tl.y() + j * _tileSize.height();
+
+			if (!QRectF(QPointF(x, y), _ozf.tileSize()).intersects(bounds())) {
+				painter->fillRect(QRectF(QPoint(x, y), _tileSize), Qt::white);
+				continue;
+			}
+
 			QString tileName(_tileName.arg(QString::number(x),
 			  QString::number(y)));
 			QPixmap pixmap;
@@ -570,25 +575,30 @@ void OfflineMap::draw(QPainter *painter, const QRectF &rect)
 			if (pixmap.isNull()) {
 				qWarning("%s: error loading tile image", qPrintable(
 				  _tileName.arg(QString::number(x), QString::number(y))));
-					painter->fillRect(QRectF(QPoint(x, y), _tileSize),
-					  Qt::white);
+				painter->fillRect(QRectF(QPoint(x, y), _tileSize), Qt::white);
 			} else
 				painter->drawPixmap(QPoint(x, y), pixmap);
 		}
 	}
-	} else if (_ozf.isOpen()) {
-		QPoint tl = QPoint((int)floor(rect.left()
-		  / (qreal)_ozf.tileSize().width()) * _ozf.tileSize().width(),
-		  (int)floor(rect.top() / _ozf.tileSize().height())
-		  * _ozf.tileSize().height());
+}
+
+void OfflineMap::drawOZF(QPainter *painter, const QRectF &rect)
+{
+	QPoint tl = QPoint((int)floor(rect.left() / _ozf.tileSize().width())
+	  * _ozf.tileSize().width(), (int)floor(rect.top()
+	  / _ozf.tileSize().height()) * _ozf.tileSize().height());
 
 	QSizeF s(rect.right() - tl.x(), rect.bottom() - tl.y());
 	for (int i = 0; i < ceil(s.width() / _ozf.tileSize().width()); i++) {
-			for (int j = 0; j < ceil(s.height() / _ozf.tileSize().height());
-			  j++) {
+		for (int j = 0; j < ceil(s.height() / _ozf.tileSize().height()); j++) {
 			int x = tl.x() + i * _ozf.tileSize().width();
 			int y = tl.y() + j * _ozf.tileSize().height();
 
+			if (!QRectF(QPointF(x, y), _ozf.tileSize()).intersects(bounds())) {
+				painter->fillRect(QRectF(QPoint(x, y), _tileSize), Qt::white);
+				continue;
+			}
+
 			QPixmap pixmap;
 			QString key = _ozf.fileName() + "/" + QString::number(x)
 			  + "_" + QString::number(y);
@@ -598,10 +608,17 @@ void OfflineMap::draw(QPainter *painter, const QRectF &rect)
 					QPixmapCache::insert(key, pixmap);
 			}
 
+			if (pixmap.isNull()) {
+				qWarning("%s: error loading tile image", qPrintable(key));
+				painter->fillRect(QRectF(QPoint(x, y), _tileSize), Qt::white);
+			} else
 				painter->drawPixmap(QPoint(x, y), pixmap);
 		}
 	}
-	} else {
+}
+
+void OfflineMap::drawImage(QPainter *painter, const QRectF &rect)
+{
 	if (!_img || _img->isNull())
 		painter->fillRect(rect, Qt::white);
 	else {
@@ -610,4 +627,13 @@ void OfflineMap::draw(QPainter *painter, const QRectF &rect)
 		painter->drawImage(rect.topLeft(), crop);
 	}
 }
+
+void OfflineMap::draw(QPainter *painter, const QRectF &rect)
+{
+	if (_ozf.isOpen())
+		drawOZF(painter, rect);
+	else if (_tileSize.isValid())
+		drawTiled(painter, rect);
+	else
+		drawImage(painter, rect);
 }

src/offlinemap.h

@@ -79,6 +79,10 @@ private:
 	bool getTileInfo(const QStringList &tiles, const QString &path = QString());
 	bool getImageInfo(const QString &path);
 
+	void drawTiled(QPainter *painter, const QRectF &rect);
+	void drawOZF(QPainter *painter, const QRectF &rect);
+	void drawImage(QPainter *painter, const QRectF &rect);
+
 	QString _name;
 	QSize _size;
 	Projection *_projection;

src/ozf.cpp

@@ -113,33 +113,26 @@ bool OZF::load(const QString &path)
 	return true;
 }
 
-QPixmap OZF::blankTile()
-{
-	QPixmap p(tileSize());
-	p.fill();
-	return p;
-}
-
 QPixmap OZF::tile(int x, int y)
 {
 	Q_ASSERT(_file.isOpen());
 
 	int i = (y/tileSize().height()) * _dim.width() + (x/tileSize().width());
 	if (i >= _tiles.size() - 1 || i < 0)
-		return blankTile();
+		return QPixmap();
 
 	int size = _tiles.at(i+1) - _tiles.at(i);
 	if (!_file.seek(_tiles.at(i)))
-		return blankTile();
+		return QPixmap();
 
 	QByteArray ba = _file.read(size);
 	if (ba.size() != size)
-		return blankTile();
+		return QPixmap();
 	quint32 bes = qToBigEndian(tileSize().width() * tileSize().height());
 	ba.prepend(QByteArray((char*)&bes, sizeof(bes)));
 	QByteArray uba = qUncompress(ba);
 	if (uba.size() != tileSize().width() * tileSize().height())
-		return blankTile();
+		return QPixmap();
 
 	QImage img((const uchar*)uba.constData(), tileSize().width(),
 	  tileSize().height(), QImage::Format_Indexed8);

src/ozf.h

@@ -24,7 +24,6 @@ private:
 	template<class T> bool readValue(T &val);
 	bool readHeaders();
 	bool readTileTable();
-	QPixmap blankTile();
 
 	QSize _size;
 	QSize _dim;