setNeedsRefresh(true);
    public void setClipPlaneEquation(int planeIndex, double clipX,            double clipY, double clipZ, double clipW) {        if (planeIndex < 0 || planeIndex >= MAX_CLIP_PLANES) {            return;        }        planeEquations[planeIndex][0] = clipX;        planeEquations[planeIndex][1] = clipY;        planeEquations[planeIndex][2] = clipZ;        planeEquations[planeIndex][3] = clipW;    }