an><span class="identifier">vec3</span><span> = </span><span class="identifier">normalize</span><span>(</span><span class="identifier">vec3</span><span>(</span><span class="identifier">uv</span><span>.</span><span class="identifier">xy</span><span>, -</span><span class="number-literal">2.0f</span><span>))
        </span><span class="identifier">dir</span><span> = </span><span class="identifier">vec3</span><span>(</span><span class="identifier">dir</span><span>.</span><span class="identifier">xy</span><span>