buildNormals();
    public void updateFromHeightMap() {        buildNormals();        if (!hasChanged())            return;        TriangleBatch batch = getBatch(0);        Vector3f point = new Vector3f();        for (int x = 0; x < size; x++) {            for (int y = 0; y < size; y++) {                point.set(x * stepScale.x, heightMap[x + (y * size)]                        * stepScale.y, y * stepScale.z);                BufferUtils.setInBuffer(point, batch.getVertexBuffer(),                        (x + (y * size)));            }        }               if (batch.getVBOInfo() != null) {            batch.getVBOInfo().setVBOVertexID(-1);            batch.getVBOInfo().setVBONormalID(-1);            DisplaySystem.getDisplaySystem().getRenderer().deleteVBO(                    getVertexBuffer(0));            DisplaySystem.getDisplaySystem().getRenderer().deleteVBO(                    getNormalBuffer(0));        }    }