package org.jzy3d.plot3d.builder.concrete;

import java.util.ArrayList;
import java.util.List;

import org.jzy3d.maths.Coord3d;
import org.jzy3d.maths.Range;
import org.jzy3d.plot3d.builder.Mapper;


public class RingGrid extends OrthonormalGrid{

	public RingGrid(float radius, int xysteps){
		this(radius, xysteps, 0);
	}
	
	public RingGrid(float radius, int xysteps, int enlargeSteps){
		super(new Range(-radius-(enlargeSteps*radius/xysteps), radius+(enlargeSteps*radius/xysteps)), xysteps);
		sqradius = (radius+(enlargeSteps*radius/xysteps)) * (radius+(enlargeSteps*radius/xysteps));
	}
	
	@Override
    public List apply(Mapper mapper) {
		double xstep = xrange.getRange() / (double)xsteps;
		double ystep = yrange.getRange() / (double)ysteps;
		
		List output = new ArrayList((xsteps-1)*(ysteps-1));
		
		for(int xi=-(xsteps-1)/2; xi<=(xsteps-1)/2; xi++){
			for(int yi=-(ysteps-1)/2; yi<=(ysteps-1)/2; yi++){
				double xval = xi*xstep;
				double yval = yi*ystep;
				
				if(sqradius >= xval*xval + yval*yval){
					output.add( new Coord3d(xval, yval, mapper.f(xval, yval) ) );
				}
			}
		}
		return output;
	}
	
	protected double sqradius;
	
	protected static final int ENLARGE_STEP = 3;
}