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oab
08-19-2005, 09:00 PM
When I have Raytrace Transparency turned on so as to be able to see the light behind a transparent surface, it works fine but the supposed transparent surface then blocks any objects behind it. Turn Raytrace Transparency off and you lose the light but you can see the objects behind.
Test1.jpeg you can see the missing part of a globe where you can't see through the transparent surface. Test2.jpeg had Raytrace Transparency turned off, so you see the globe but not the light. I'd appreciate any help where I'm going wrong.
Thanks
Mike

oab
08-19-2005, 11:36 PM
Just an update, I've continued experimenting and replaced the wire globe with a full sphere and the problem went away. Seems to be issue with a object/surface made up of two point polys. Any suggestions welcome as I need to see a wire globe, so I may have to go back to the old fashioned pretend spotlight using a cone etc.
Thanks
Mike

toby
08-20-2005, 12:56 AM
This is very confusing - what is behind what? And lights themselves are invisible, so is that a lens flare?
What is the object that we're supposed to see? All we can see is a globe and the lens flare(?), I see a black edge, but is that in front or behind the globe, the light, etc.

oab
08-20-2005, 01:42 AM
Hi Toby,
Thanks, I was hoping someone had seen this before without getting too long winded. Anyway the wireframe globe is at the back with a spotlight pointing toward the camera, with volumetrics on, projecting an image onto a simple polygon, as in added pic. The polgon has a feathered oval transparency map applied so you don't see a square outline. I need Ray Trace Transparency on so you can see the volumetric lighting as the polygon passes in front of the spotlight. But with this turned on the transparent part of the polygon blocks out the wireframe object as in previous image. Only does this with two point polygon object. If I replace wire globe with full sphere, it works fine.
Hope this is clearer, if not, I'll give it a rest for the rest of the day, been at it too long.
Thanks
Mike

toby
08-20-2005, 02:43 AM
Gotcha.

Volumetrics are a post-process, and so are the 2-point polygons, therefore neither will inherently ray-trace; that's what ray trace transparency was created for, so that volumetrics would render behind clear objects. Unfortunately this doesn't work for 2-point polygons, but fortunately all you have to do is make the globe real geometry so it will show up. If you still have splines that you made it with, you can do rail extrudes, or you can make a globe image to use as a clip map, maybe a couple other ways -

Another option is to render separate passes and composite them together - this would give you added flexibility and may save render time too.

oab
08-20-2005, 02:59 AM
Hi Toby,
Many Thanks, sorry about being clear as mud, it's been a long day. I'll get back to the client as it was he who wanted the wire look, I prefer the clip mapped or real satelite imagery look myself so it's obvious which way it's spinning, but what do I know when he's paying. Once again thanks,
Mike