iption">
        <h2>Description</h2>
        <p>
            Available only in the fragment language, <code class="varname">gl_FragCoord</code> is an input variable that contains the
            window relative coordinate (x, y, z, 1/w) values for the fragment. If multi-sampling,
            this value can be for any location within the pixel, or one of the fragment samples.
            This value is the result of fixed functionality that interpolates primitives after vertex
            processing to gener