@Override
public void mousePressed(MouseEvent evt) {
if (!SwingUtilities.isLeftMouseButton(evt)) return;
prev = evt.getPoint();
priorCursor = viewer.getCursor();
viewer.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
}
@Override
public void mouseDragged(MouseEvent evt) {
if (!SwingUtilities.isLeftMouseButton(evt)) return;
Point current = evt.getPoint();
double x = viewer.getCenter().getX();
double y = viewer.getCenter().getY();
if (prev != null) {
x += prev.x - current.x;
y += prev.y - current.y;
}
if (!viewer.isNegativeYAllowed()) {
if (y < 0) {
y = 0;
}
}
int maxHeight =
(int)
(viewer.getTileFactory().getMapSize(viewer.getZoom()).getHeight()
* viewer.getTileFactory().getTileSize(viewer.getZoom()));
if (y > maxHeight) {
y = maxHeight;
}
prev = current;
viewer.setCenter(new Point2D.Double(x, y));
viewer.repaint();
}
@Override
public void mouseReleased(MouseEvent evt) {
if (!SwingUtilities.isLeftMouseButton(evt)) return;
prev = null;
viewer.setCursor(priorCursor);
}