Method lookUp

src/main/java/field/graphics/Camera.java:213–219

(float r)

			return s;
		}

		public State lookUp(float r) {
			State s = copy();
			Quat q = new Quat().fromAxisAngleRad(left(), r);
			s.target = Vec3.add(position, q.transform(ray().mul(1)), new Vec3());
			s.up = q.transform(up);
			return s;
		}