/mo>
                    <mi mathvariant="italic">width</mi>
                    <mo>-</mo>
                    <mn>1</mn>
                </mrow>
            </math>,
            inclusive.  This region may not include any texels
            outside the range of the texture array as it was originally specified.  It
            is not an error to specify a subtexture with width of 0, but such a
            specification has no effect.
        </p><p>
            <em class="parameter"><code>internalformat</c