code: public void setXYZ(Point3D pt) {
  		_touch();
  		boolean bHasZ = hasAttribute(Semantics.Z);
  		if (!bHasZ && !VertexDescription.isDefaultValue(Semantics.Z, pt.z)) {// add
  																				// Z
  																				// only
  																				// if
  																				// pt.z
  																				// is
  																				// not
  																				// a
  																				// default
  																				// value.
  			addAttribute(Semantics.Z);
  			bHasZ = true;
  		}
  
  		if (m_attributes == null)
  			_setToDefault();
  
  		m_attributes[0] = pt.x;
  		m_attributes[1] = pt.y;
  		if (bHasZ)
  			m_attributes[2] = pt.z;
  	}
docs: Sets the XYZ coordinates of this point.
  
  @param pt
  The point to create the XYZ coordinate from.