public void setArg(int index, Matrix3f mat) {
        TempVars vars = TempVars.get();
        try {
            Matrix4f m = vars.tempMat4;
            m.zero();
            for (int i = 0; i < 3; ++i) {
                for (int j = 0; j < 3; ++j) {
                    m.set(i, j, mat.get(i, j));
                }
            }
            setArg(index, m);
        } finally {
            vars.release();
        }
    }
Returns the maximal work group size when this kernel is executed on
the specified device

@param device the device
@return the maximal work group size
jme3-core/src/main/java/com/jme3/opencl/Kernel.java