View Full Version : Renderman Arealight issue

03 March 2008, 03:24 PM
Can someone point me in the right direction to fix this? It seems renderman does not accurately respect maya area lights. Do I need a custom arealight shader?

I actually have a lcd panel that is lighting a small scene and would like the use an arealight to fake panel illumination rather than GI. Also when I map a image to the arealight it reponds differently to other renders such as software or MR. Its like it just textures the objects with that image where light is illuminating. Why is this?

Thanks in advance...

03 March 2008, 04:07 PM
well i dont know much at all of render man, but it looks like the balls in the shadow are reflecting the balls in the light? are they highly reflective? is there decay on the light?

also if the area light is physical (like a light card) you could be getting relfections from the backside of the light card.

im not sure tho, just spitballing here

03 March 2008, 04:40 PM
oh sorry,

yeha I spent so long trying to fix this it was pretty late and I didnt pay attention. He is a clearer example.

03 March 2008, 05:39 PM
hi ,
Like with mental ray , you will have to turn on special attributes for area lights . If you havent already , check if u have added the arealight specific attibutes from the menu on top of attribute editor . It will be added in the extra attrubite option . hope this helps

03 March 2008, 05:03 AM
yea default area lights from mentalray don't work with renderman. Partly because they're for mentalray. :) I'll have to check the attribute add functions, but I'm sure theres something there about it.

03 March 2008, 05:54 AM
err im not using mental ray area lights, Bog standard maya area light.

adding renderman attrs dont do anything in regards to removing the problem. have since tried custom light shader too with no luck.

I have really spend some time trying to figure this out and really would just like somone with renderman for maya to do the same test, so at least I know if it is local issue or a natural renderman for maya problem...

03 March 2008, 09:45 AM
i'll do the test as soon as i can a and let you know



03 March 2008, 02:35 PM

I dont use Rm4M, but rather Renderman Studio. But I can see the situation you are reporting

Are you trying to use depth map shadows? If I switch to raytraced shadows then this behaviour is not present.


03 March 2008, 05:38 PM
i tried this thingy , and it gave me the same result as yours , even with RMan area light attrs added and shadows attrs added with shadows on ( dmap or raytraced ), bizzare , if i have time i'll try to see what the problem is and let you know



03 March 2008, 01:49 AM
did you try to render with rms or rfm ?

rms works but I heard some strange problem with the cracked release of rms so be sure you are using a valid license and release of the software.

03 March 2008, 03:38 PM
Maybe it is really the cracked version of RFM or RMS ! Lolz

03 March 2008, 12:22 AM

I've filed a bug report on this. Sorry about the trouble.


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