Just for the sake of posting something here in years I though I'd present another way of doing this. This gives you a little bit of control over the flickering. The $fFreq controls the speed of the flickering. $fMinIntensity is the threshold value the noise function has to exceed in order to turn the light on at all. $fMaxIntenxity does what it says on the tin. Another plus side is that you'll get always the same results. Code: float $fFreq = 15.0; float $fMinIntensity = 0.5; float $fMaxIntenxity = 1.0; float $fIntensity = $fMaxIntenxity * .5 * (1 + noise(time * $fFreq)); if($fIntensity > $fMinIntensity) pointLightShape1.intensity = $fIntensity; else pointLightShape1.intensity = 0.0;