View Full Version : How to make a square light?

10 October 2006, 05:09 PM
Ok here's my question and i only ask because i've spent the last two hours looking for a solution and im hoping someone has tried this.

I am trying to make a projector in a theater type atmosphere, i created the spot light and placed it behind a grid so that i could use the grid to cut the edge of the light, since i cant find a square light, now i can put the light behind the grid and get the look i need then i apply the fast light effects to the light in order to achieve a smoky seedy atmosphere in the room, as soon as i do this the light is no longer square as if its passing through the grid, so i enable volume shadows on the fast light effects, this helps a little but the light is still round and casting outside the hole in the grid, if i remove the fast light effects the light is perfectly square again thanks to the grid.

So first question
Is there a square light somewhere in XSI?
and second
is there a way to mask a light so that you can force it to be square?, round lights are not always the answer.


11 November 2006, 11:32 AM

have you tried using the get primitive>light>light box? this is a spotlight with a rectangular area light. also you could use a image with a square mask on the grid or cut out the polyons to leave a square border. As far as I can remeber you also need to set the shadows umbra to 0 .

>edit< couldnt resist seeing if this works or not, /puts money where the mouth is... here is an example image, I took a screenshot

11 November 2006, 12:25 PM
plugin the sib_slide_proj node into the light shader... an use an alpha map...

11 November 2006, 10:17 PM
Thanks for the responses i was hoping there was a quick way.

oh well thanks again.

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11 November 2006, 10:17 PM
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