View Full Version : OGL spotlight cone

06-12-2005, 11:10 PM

I've spent about an hour trying to sort out how to turn on a visible spotlight cone in OGL. Would someone kindly enlighten me? ;)

Also, I'm having difficulty finding some volumic light controls. I have volumes rendering nicely on my spotlight, but I want the volumic to originate right at the light, so that it is shaped like a cone, but the volume starts some distance away, making it more like a cylinder. Is there a "beginning" and "end" distance parameter for the volumic?

Many thanks


06-12-2005, 11:29 PM
to get your cone press B

in your light properties turn on light fall off and turn it to liniar, now you can control your falloff with the manipulator.

BTW B also brings up manipulaters that are usefull for objects as well.


06-13-2005, 12:17 AM
Thanks Greg. That was very helpful.

One thing, though. The volumic did not change in the render view until I clicked Property>volumic again to overwrite the parameters. I'm curious why they did not change when I changed the light's falloff parameters.

Are volumic falloff parameters not adjustable independantly from the light's falloff parameters?


06-13-2005, 05:53 AM
There are a few property pages, or even single properties that don't trigger a refresh of the interactive render... There aren't many, but there are a few.

When you run into these, you might find it useful to key a value within the same ppg, sometimes that will work. Otherwise, you can hit q and right-click on the region area and that will refresh the render.

In terms of the non-cone shape though - that's controlled with the Min Distance setting in the Light's Volumic Property. Be aware that when you have a volumic light source in the scene, a Volumic Properties appears at the scene level as well with a few more global controls.


06-13-2005, 08:49 AM
also i think you have to hit that button on the volumic page to trigger the volumic maps to be used in the region.. i maybe wrong though

06-13-2005, 02:24 PM
Jean-Paul and Strang thankyou.

I have found the scene level volumic properties, but in the Light Properties panel, I am unable to find the individual light volumic parameters. Can you tell me where to find them?

Many Thanks


06-13-2005, 02:39 PM
Pretty much any time you Get->Property->Property you're either adding a new property to your object, or creating a local copy of a property that the object had previously been inheriting. For example, every object is by default sharing the scene's Geometry Approx property. You can tell it is being inherited or shared by it's italics.

Anyways... to find these properties, just pop open an Explorer and expand your light - you'll see a Volumic Property there. Click on the square icon beside it.

Or, with your light selected, press alt-enter and you'll get a tabbed property page with all the light's properties.

06-13-2005, 05:11 PM
Sweet! I didn't realize all parameters were in the explorer. Very powerful and easy to find params! Thanks.


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