CGTalk - Decay Rate on a Spot Light...

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TumikSmacker

11-20-2002, 06:02 AM

This may be a stupid question but anyway...

I have the Decay Rate set to 'No Decay' and the Intensity to 1 on a spot light. If I switch the Decay Rate to Quadratic I have to bump up the Intensity or my scene wont even be lit.
Here's my question
When going from No Decay to Quadratic does anyone know the ratio for the Intensity between the two? Like if the 'No Decay' has an intensity of 1 and I put it to Quadratic should I bump up the Intensity to 1000 to get basically the same lighting force/intensity.

How I made it clear what I'm asking :scream:

beaker

11-20-2002, 06:45 AM

The intensity goes down by a factor of 4 for every unit away from the center it goes. So lets say you have a spot light with the focal point is 5 units away from the start point. 1 unit away it is 1/4th as bright, 2 units it is 1/16th as bright, 3 units it is 1/64th as bright, 4 units away it is 1/256th as bright and 5 units away it is 1/1024th as bright.

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