public void calculateCenter() {
        if (center == null) {
            center = new Vector3f(pointA);
        } else {
            center.set(pointA);
        }
        center.addLocal(pointB).addLocal(pointC).multLocal(FastMath.ONE_THIRD);
    }
Recalculates the stored centroid based on the current vertex locations.
jme3-core/src/main/java/com/jme3/math/Triangle.java