// Copyright 2002, FreeHEP.
package org.freehep.graphicsio.emf.gdi;

import com.google.code.appengine.awt.geom.AffineTransform;
import java.io.IOException;

import org.freehep.graphicsio.emf.EMFInputStream;
import org.freehep.graphicsio.emf.EMFOutputStream;
import org.freehep.graphicsio.emf.EMFTag;
import org.freehep.graphicsio.emf.EMFRenderer;

/**
 * SetWorldTransform TAG.
 * 
 * @author Mark Donszelmann
 * @version $Id: SetWorldTransform.java 10367 2007-01-22 19:26:48Z duns $
 */
public class SetWorldTransform extends EMFTag {

    private AffineTransform transform;

    public SetWorldTransform() {
        super(35, 1);
    }

    public SetWorldTransform(AffineTransform transform) {
        this();
        this.transform = transform;
    }

    public EMFTag read(int tagID, EMFInputStream emf, int len)
            throws IOException {

        return new SetWorldTransform(emf.readXFORM());
    }

    public void write(int tagID, EMFOutputStream emf) throws IOException {
        emf.writeXFORM(transform);
    }

    public String toString() {
        return super.toString() + "\n  transform: " + transform;
    }

    /**
     * displays the tag using the renderer
     *
     * @param renderer EMFRenderer storing the drawing session data
     */
    public void render(EMFRenderer renderer) {
        if (renderer.getPath() != null) {
            renderer.setPathTransform(transform);
        } else {
            renderer.resetTransformation();
            renderer.transform(transform);
        }
    }
}