// License: GPL. For details, see LICENSE file.
package org.openstreetmap.josm.command;
import static org.openstreetmap.josm.tools.I18n.trn;
import java.util.Collection;
import javax.swing.Icon;
import org.openstreetmap.josm.data.coor.EastNorth;
import org.openstreetmap.josm.data.osm.Node;
import org.openstreetmap.josm.data.osm.OsmPrimitive;
import org.openstreetmap.josm.tools.ImageProvider;
/**
* RotateCommand rotates a number of objects around their centre.
*
* @author Frederik Ramm
*/
public class RotateCommand extends TransformNodesCommand {
/**
* Pivot point
*/
private EastNorth pivot;
/**
* angle of rotation starting click to pivot
*/
private double startAngle = 0.0;
/**
* computed rotation angle between starting click and current mouse pos
*/
private double rotationAngle = 0.0;
/**
* Creates a RotateCommand.
* Assign the initial object set, compute pivot point and inital rotation angle.
*/
public RotateCommand(Collection<OsmPrimitive> objects, EastNorth currentEN) {
super(objects);
pivot = getNodesCenter();
startAngle = getAngle(currentEN);
rotationAngle = 0.0;
handleEvent(currentEN);
}
/**
* Get angle between the horizontal axis and the line formed by the pivot and give points.
**/
protected final double getAngle(EastNorth currentEN) {
if ( pivot == null )
return 0.0; // should never happen by contract
return Math.atan2(currentEN.east()-pivot.east(), currentEN.north()-pivot.north());
}
/**
* Compute new rotation angle and transform nodes accordingly.
*/
@Override
public final void handleEvent(EastNorth currentEN) {
double currentAngle = getAngle(currentEN);
rotationAngle = currentAngle - startAngle;
transformNodes();
}
/**
* Rotate nodes.
*/
@Override
protected void transformNodes() {
for (Node n : nodes) {
double cosPhi = Math.cos(rotationAngle);
double sinPhi = Math.sin(rotationAngle);
EastNorth oldEastNorth = oldStates.get(n).eastNorth;
double x = oldEastNorth.east() - pivot.east();
double y = oldEastNorth.north() - pivot.north();
double nx = cosPhi * x + sinPhi * y + pivot.east();
double ny = -sinPhi * x + cosPhi * y + pivot.north();
n.setEastNorth(new EastNorth(nx, ny));
}
}
@Override
public String getDescriptionText() {
return trn("Rotate {0} node", "Rotate {0} nodes", nodes.size(), nodes.size());
}
@Override
public Icon getDescriptionIcon() {
return ImageProvider.get("data", "node");
}
}