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Eliade
05-06-2007, 01:07 AM
Hi

Is there anyway to override the ray recursion limit to get it up to like 50 instead of 24 max???
I have a complex transparent shape that curls onto itself, so I sometime get more than 24 transparent polygons in alignment with the camera...
due to the ray recursion limit set to 24, any transparent polygon present after the 24th polygon will simply be black ( with the ray trace shadows enabled) which look really bad on my image...

I made the shape using some point jitter, so it's "manually impossible" to remove those extra polygons

Thanks

Sensei
05-06-2007, 02:13 AM
No..

BTW, it would be really weird if you would see ray recursion limit influence.. f.e. Reflection is set to 90%, this means that 90% of color is taken from reflected surface, and 10% of the rest, diffuse, specular etc.. 2nd time it's 90% of 90%.. 0.9 * 0.9 = 0.81... then 24 times like this is 0.9 to power 24.. approximately 0.08.. 8% of black is influencing.. If I calculated it right.. ;)

Show picture, this will help fixing your problem..

Black color from 24 recursion does not have to be black - it's Backdrop color controlled by settings Ctrl-F5.. You can put there environment map..

jameswillmott
05-06-2007, 05:26 AM
You can use the Classic camera provided you don't have refractions or raytraced transparency turned on...

Andyjaggy
05-06-2007, 11:08 AM
Lots of people have been asking for this for a long time. There is probably a little line of code somewhere that they just need to change from 24 to 100 :) Probably not that simple but you never know.

Eliade
05-06-2007, 11:40 AM
Thanks for your valuable information, I now understand exactly what's happening
(on this image I changed the backdrop color to orange)
The classic camera solved the problem but is so long about 3X longer with no antialiasing

I was thinking to render just the ground which will take less than a second per frame (total about 900 frames), and then composite the image later, but the alpha from the perspective camera is not helping, if you look close there's some blue in front of the "artifact", but the alpha is pure white at this place so I won't be able to do that.

But I want to try to use the perspective camera, in the last resort I'll render it using the classic camera
The only way I can think of would be to set the ground render as backdrop. In that case is there anyway to set animated frame as a backdrop...

Eliade
05-06-2007, 12:48 PM
I tried to put a movie as a backdrop and it worked

Thanks for your help

FractalDimensia
10-04-2015, 12:19 PM
Somewhat new to LightWave and using 2015, and just ran into this limitation. I find it weird that, with so much advancement in speed and capabilities, NewTek hasn't changed this in all this time.

But hey, just on the outside chance, does anyone know of a way to break the limit of 64? I have an object with 82 layers of polys that have parts that are transparent. But rays aren't making it through to the other side. A bump to 100 would be adequate.

Any suggestions would be appreciated!

Kryslin
10-10-2015, 05:30 PM
Which version of 2015? At some point they introduced per surface clip maps; If you assign a clip map to the part of the surface that's 100% transparent, Lightwave won't register the ray intersection with geometry. This can cut down on the need to bounce those rays around so much. Clip mapping is also all or nothing; Either the map blocks the ray, causing the spot to be evaluated, or it lets it pass.

I use this on xFrog plants a lot.

Sensei
10-10-2015, 05:40 PM
Which version of 2015? At some point they introduced per surface clip maps; If you assign a clip map to the part of the surface that's 100% transparent, Lightwave won't register the ray intersection with geometry. This can cut down on the need to bounce those rays around so much. Clip mapping is also all or nothing; Either the map blocks the ray, causing the spot to be evaluated, or it lets it pass.

OP wants to have higher recursion limit than is able to enter in Render Globals panel.
Of course we can decrease from limit couple various ways (simply not use anymore reflection/refraction at bounce xxx), but he want to extend limit..