public void updateMeanNormal() { final Vector3 normal = new Vector3(0, 0, 0); for (final IFace face : faces) { normal.addLocal(face.getMeanNormal()); } final float len = normal.length(); if (len < 1e-6) { normal.set(0, 0, 1); } else { normal.divideLocal(len); } this.meanNormal = normal; }