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dmack
07-18-2008, 11:44 AM
Hi All,

OK in LW9.3.1 if I have a ball that is semi-transparent and put a box inside it, then make the box completely 100% transparent (and no spec or reflection) and turn on ray trace refraction....I would have thought I wouldn't see the box inside the ball, as it's 100% transparent...but I do. THat's a bug right? Can anyone tell me how to get around it - it's causing real problems on my current project...

dmack
07-18-2008, 11:57 AM
Doesn't seem to happen on LW9.2 - This does appear to be a bug....bit of a biggie really!

Giacomo99
07-18-2008, 12:49 PM
Depending on the lighting of the scene and the other surface characteristics, 100% transparency can be invisible or not invisible. (This is true for every 3D app I've ever used.)

If you post a render and some more details of the surface, people here might be able to help you.

dmack
07-21-2008, 01:09 AM
Disagree. If the surface is 100% transparent, does not reflect or refract, does not colour filtre, then it should be completely unseen. It's essential to doing so many effects in animations and stills. If you can't rely on transparency to do it, then you need dissolve to be mappable. I personally think it's a bug that has been introduced in 9.3 or 9.31 because it doesn't happen in 9.2. If anyone has any info on whether this is a known bug, I'd love to hear. If it's not seen as a bug and Newtek aren't going to 'fix' it, I'd also like ot hear!

toby
07-21-2008, 01:26 AM
Hmmm
I doubt it's a bug, because there's a dozen ways to have opacity composited into the final render, so any way you do it, someone's going to say it's wrong. Refraction uses the normals of the polygons it hits, that's probably what's showing up. Whether it's transparent and whether it bends light are two different things. Someone would certainly complain "I want it to refract even though it's transparent, just like glass".

If you have different transparencies that you want to behave differently, ( in other words, you want explicit control like the rest of us ), you'll have to render them separately and composite them.

You could also try clip mapping, although it doesn't support partial transparency.

dmack
07-21-2008, 03:33 AM
Now I'm worried! It didn't happen in LW9.2 and I used the ability to do it all in one pass again and again and again - are we seriously saying that this new way of doing it is here to stay?!?!!? I'd be seriously dissappointed. I love the flexibility to LW's transparency etc, this would be a blow to me. Any official word on this? Is it down as a bug in any of the buglists?!?!?

Chuck
07-21-2008, 05:07 PM
Now I'm worried! It didn't happen in LW9.2 and I used the ability to do it all in one pass again and again and again - are we seriously saying that this new way of doing it is here to stay?!?!!? I'd be seriously dissappointed. I love the flexibility to LW's transparency etc, this would be a blow to me. Any official word on this? Is it down as a bug in any of the buglists?!?!?

Just report the bug to our Fogbugz database with content, please, and we'll look into it.

toby
07-21-2008, 09:27 PM
Now I'm worried! It didn't happen in LW9.2 and I used the ability to do it all in one pass again and again and again - are we seriously saying that this new way of doing it is here to stay?!?!!? I'd be seriously dissappointed. I love the flexibility to LW's transparency etc, this would be a blow to me. Any official word on this? Is it down as a bug in any of the buglists?!?!?
You gotta go with the flow man! Things don't get any better without change. And try compositing, there's a lot of benefits. You could always go back to 9.2 also. But submit it as a bug too, it still might be one.

dmack
07-28-2008, 08:35 AM
You gotta go with the flow man! Things don't get any better without change. And try compositing, there's a lot of benefits. You could always go back to 9.2 also. But submit it as a bug too, it still might be one.


Trust me, this is NOT better! The other way gave you soooo much more flexibility. How can having to composite be better thna being able to do it in Lightwave? It's a bug and it's gotta go! Now how do I do this fogbugz thing?!?!

dmack
07-28-2008, 09:22 AM
Done! Added to fogbugz (15092). That was pretty painless!

toby
07-31-2008, 01:52 AM
if I have a ball that is semi-transparent and put a box inside it, then make the box completely 100% transparent (and no spec or reflection) and turn on ray trace refraction....I would have thought I wouldn't see the box inside the ball, as it's 100% transparent...but I do.
Just tried this in 9.3, it does what you said, until I turn on double-sided for the ball, then the box is invisible. Does that help?

dmack
07-31-2008, 02:22 AM
Hey thanks Toby - I'll use that. I've filed it as a bug so let's see what comes back.

dmack
08-27-2008, 04:18 AM
This bug, has now been fixed....Thanks Newtek Team - great to see stuff like this being dealt with! Cool!