public HitRecord intersect(Ray r) {
HitRecord h = rectangle.intersect(r);
if (h == null) return null;
h.intersectable = this;
h.material = this.areaLightMaterial;
h.p = 1.f / area;
return h;
}
/** Sample a point on the light geometry. */
public HitRecord sample(float[] s) {
HitRecord hitRecord = new HitRecord();
Vector3f edge1Sampled = new Vector3f(edge1);
edge1Sampled.scale(s[0]);
Vector3f edge2Sampled = new Vector3f(edge2);
edge2Sampled.scale(s[1]);
Point3f position = new Point3f(this.lightPos);
position.add(edge1Sampled);
position.add(edge2Sampled);
hitRecord.position = position;
hitRecord.intersectable = this;
hitRecord.material = this.areaLightMaterial;
hitRecord.normal = new Vector3f(this.normal);
hitRecord.p = 1.f / area;
return hitRecord;
}