How to use

subtract

method

in

com.ardor3d.math.Vector4

/**
 * Subtracts the values of the given source vector from those of this vector and returns them in store.
 * 
 * @param source
 * @param store
 *            the vector to store the result in for return. If null, a new vector object is created and returned.
 * @return (this.x - source.x, this.y - source.y, this.z - source.z, this.w - source.w)
 * @throws NullPointerException
 *             if source is null.
 */
@Override
public Vector4 subtract(final ReadOnlyVector4 source, final Vector4 store) {
  return subtract(source.getX(), source.getY(), source.getZ(), source.getW(), store);
}

@Test
public void testSubtract() {
  final Vector4 vec1 = new Vector4();
  final Vector4 vec2 = new Vector4(Vector4.ONE);
  vec1.subtractLocal(1, 2, 3, 4);
  assertEquals(new Vector4(-1, -2, -3, -4), vec1);
  vec1.subtractLocal(-1, -2, -3, -4);
  assertEquals(Vector4.ZERO, vec1);
  vec1.zero();
  vec1.subtractLocal(vec2);
  assertEquals(Vector4.NEG_ONE, vec1);
  vec1.zero();
  final Vector4 vec3 = vec1.subtract(vec2, new Vector4());
  assertEquals(Vector4.ZERO, vec1);
  assertEquals(Vector4.NEG_ONE, vec3);
  final Vector4 vec4 = vec1.subtract(0, 0, 0, 1, null);
  assertEquals(Vector4.ZERO, vec1);
  assertEquals(Vector4.NEG_UNIT_W, vec4);
}

/**
 * Subtracts the values of the given source vector from those of this vector and returns them in store.
 * 
 * @param source
 * @param store
 *            the vector to store the result in for return. If null, a new vector object is created and returned.
 * @return (this.x - source.x, this.y - source.y, this.z - source.z, this.w - source.w)
 * @throws NullPointerException
 *             if source is null.
 */
@Override
public Vector4 subtract(final ReadOnlyVector4 source, final Vector4 store) {
  return subtract(source.getX(), source.getY(), source.getZ(), source.getW(), store);
}