package ch.epfl.alpano.dem;

import ch.epfl.alpano.Interval2D;
import static java.lang.Math.PI;
import static java.lang.Math.sin;
import static java.lang.Math.cos;

final class WavyDEM implements DiscreteElevationModel {
  private final static double PERIOD = 100, HEIGHT = 1000;
  private final Interval2D extent;

  public WavyDEM(Interval2D extent) {
    this.extent = extent;
  }

@Override
  public void close() throws Exception { }

  @Override
  public Interval2D extent() { return extent; }

  @Override
  public double elevationSample(int x, int y) {
    double x1 = PI * 2d * x / PERIOD;
    double y1 = PI * 2d * y / PERIOD;
    return (1 + sin(x1) * cos(y1)) / 2d * HEIGHT;
  }
}