TestQuaternions.java

package mikera.vectorz;

import static org.junit.Assert.*;
import mikera.matrixx.Matrix33;
import mikera.matrixx.Matrixx;

import org.junit.Test;

public class TestQuaternions {
	@Test public void testInvert() {
		assertEquals(Vector4.of(0,0,0,1),Quaternions.invert(Vector4.of(0,0,0,1)));
		
		Vector4 a=Vector4.of(1,2,3,4);
		Vector4 b=Quaternions.invert(a);
		
		Vector4 r1=Quaternions.mul(a,b);
		// assertEquals(Vector4.of(0,0,0,1),r1);
		assertTrue(r1.epsilonEquals(Vector4.of(0,0,0,1)));
		
		Vector4 r2=Quaternions.mul(b,a);
		// assertEquals(Vector4.of(0,0,0,1),r2);
		assertTrue(r2.epsilonEquals(Vector4.of(0,0,0,1)));
	}
	
	@Test public void testRotate() {
		Vector3 axis=new Vector3(1,0,0);
		Vector3 v=new Vector3(0,1,0);
		double angle=0.5*Math.PI;
		
		Matrix33 rotM = Matrixx.createRotationMatrix(axis, angle);
		Vector4 rotQ = Quaternions.axisAngle(axis, angle);
		
		Vector3 mv=rotM.innerProduct(v);
		Vector3 qv=Quaternions.rotate(rotQ, v);
		
		assertEquals(mv,qv);
		assertTrue(mv.epsilonEquals(qv));
	}
}