��directional” and “ambient” lights).
attenuation = 1/(a0 + d*a1 + d^2*a2) where d = distance to light.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters<span class="colon">:</span></dt>
<dd class="field-odd"><p><strong>d</strong> (<em>float</em>) – The distance to evaluate.</p>
</dd>
<dt class="field-even">Returns<span class="colon">:</span></dt>
<dd class="field-even"><p>0 if a0 + d*a1 + d^2*a2 &lt;= 0.</p>
</dd>
<dt class="field-odd">Return type<span class="colon">:</span></dt>
