Ring fill generator for CDK

RingPlateGenerator.java

package customgenerator;

import java.awt.Color;
import java.util.ArrayList;
import java.util.List;

import javax.vecmath.Point2d;
import javax.vecmath.Vector2d;

import org.openscience.cdk.geometry.GeometryTools;
import org.openscience.cdk.interfaces.IAtom;
import org.openscience.cdk.interfaces.IAtomContainer;
import org.openscience.cdk.interfaces.IRingSet;
import org.openscience.cdk.renderer.RendererModel;
import org.openscience.cdk.renderer.elements.ElementGroup;
import org.openscience.cdk.renderer.elements.IRenderingElement;
import org.openscience.cdk.renderer.elements.PathElement;
import org.openscience.cdk.renderer.generators.IGenerator;
import org.openscience.cdk.renderer.generators.IGeneratorParameter;
import org.openscience.cdk.ringsearch.SSSRFinder;

public class RingPlateGenerator implements IGenerator<IAtomContainer> {

    @Override
    public List<IGeneratorParameter<?>> getParameters() {
        return new ArrayList<IGeneratorParameter<?>>();
    }

    @Override
    public IRenderingElement generate(IAtomContainer atomContainer, RendererModel model) {
        ElementGroup ringPaths = new ElementGroup();
        SSSRFinder ringFinder = new SSSRFinder(atomContainer);
        IRingSet ringSet = ringFinder.findSSSR();
        for (IAtomContainer ring : ringSet.atomContainers()) {
            ringPaths.add(generateRing(ring));
        }
        return ringPaths;
    }
    
    private PathElement generateRing(IAtomContainer atomContainer) {
        Point2d center = GeometryTools.get2DCenter(atomContainer);
        List<Point2d> points = new ArrayList<Point2d>();
        for (IAtom atom : atomContainer.atoms()) {
            Point2d p = atom.getPoint2d();
            Vector2d v = new Vector2d(center);
            v.sub(p);
            v.scaleAdd(0.2, v, p);
            points.add(new Point2d(v));
        }
        return new PathElement(points, Color.DARK_GRAY);
    }

}