View Full Version : Maya 8 - MentalRay AreaLights

10 October 2006, 10:40 PM
i already posted a bug report to autodesk, but still i want to comment about that here :

the new MR arealights are nice and everything but still have a very severe bug ...
when you make an area light, switch on the MR option, set the high samples to 32, high sample limit to 2 , low samples to 16, it renders fine ... but when u save the scene, open it up again it is grainy ... why ? because the settings are now : 16, 2 , 1 ....
save it this way, open again, now its 8,2,1 ...
looks like maya sets the high samples to the value the low samples are set if they are above 1 ...
workaround : key the high samples and the low samples ... problem with that : low samples will lose its connection and will be set to 1 again ... only high samples will be kept .. .

actually working workaround : run a pre-render-mel script thats sets the high and low limits for each light ... but that sucks ...
if anyone comes up with a solution to the problem (probably in the area light script of maya) i would appreciate it ,.. i dont know when maya 8.0.1 comes out and if that even fixes the problem ...

10 October 2006, 04:52 PM
ya that happend to me too, :D

10 October 2006, 11:08 PM
yeah, this is an annoying bug :hmm:

10 October 2006, 11:32 PM
I wrote a script that added two new attributes to areaLight called lowSample and HighSample and connected them areaLightShape's equivalent fields thinking it would then hold the values nomatter what.

Well, on bringing up the scene again, HighSamples was correct as expected, but the LowSamples connection was automatically broke and the expression changed! It went from

areaLightShape1.areaLoSamples = areaLight1.lowSamples;


.O[0] = areaLight1.MinSamples;

wtf? I thought it was an easy work around, but no... Maya had to go and rewrite my stuff.

10 October 2006, 12:43 PM
Workaround: don't use the new arelight.. or pray the lord :twisted:

10 October 2006, 01:19 PM
it's a bug and it occurs when you have a low samples value different than the default <1>
when you open the scene again maya just sets the high samples as your low samples were and leaves the low samples to 1.

tho that's not a reason not to use these rocking area lights! :D

10 October 2006, 04:45 PM
Jeez what a stupid bug... it seems to me that those area lights were perhaps a tad of a rushed job for such a bug to escape their testing. Hope they are planning a patch release soon, hopefully they can address this and perhaps implement the MR 3.5 FG auto mode and multi mode officially too.. and also perhaps that little bit about the cc-meshes.


10 October 2006, 02:21 PM
Hi, in maya 8 . I create a light ...but the mr tab no area lights....did Autodesk ...move it somwhere elso or??? Does anybody have same prob?

10 October 2006, 02:36 PM
ya Maya 8 has changed

just create a normal area light and that will have hte mental ray att. in it

10 October 2006, 02:39 PM
10x man...i find new maya ..."maxed" :)

10 October 2006, 07:12 PM
by the way , i recieved notice from autodesk that this bug is now officially under investigation and will be fixed in an upcoming release ...
wasnt fixed in the patch 3 though .....
hopefully it will with maya 8.01 or so ...

other than that, i still like the new mr area lights a lot :)

11 November 2006, 02:05 AM
I found the problem- it was a name collision in the creation of the samples attributes. Maybe other people found it too. You can download the fix here: (


11 November 2006, 02:35 AM
I have also written a few new scripts I use for creating area lights. (

This one creates an area light with a physical shader, but makes connections so that you control the lights color and intensity through the normal maya attributes at the top of the attribute editor (kind of handy). It also sets up the photon energy to be physically accurate (the photon color in the editor doesn't always reflect the changes, but it still renders correct).

Try it, edit it.

11 November 2006, 10:41 AM
Thanks man, I'll test it soon.

11 November 2006, 11:16 AM
great Shawn :thumbsup:

11 November 2006, 06:51 AM
Thanks a lot, Shawn! :) The Physical Area Light script is handy and the samples fix is a must have. Nice work!

11 November 2006, 06:58 PM
NP! :thumbsup: One thing though- the fix only effects new area lights. You might have to remake some lights in old scenes.

11 November 2006, 03:31 AM
Hey Shawn,

Thanks for your area light fix. I doubt that Autodesk would ever address a bug that just requires a 1 letter fix with a quick patch. They'd probably want to accumulate a lot of bug fixes before releasing a patch.


11 November 2006, 09:18 AM
Thx a lot man, it'always good to see people that share things! :thumbsup:


12 December 2006, 06:34 PM
So now the new area light is created by creating a normal area light? Not with a spot converted to an arealight?

and yea, is it usefull to use a area light if you arent planning in using area shadows? For example in the use for fill lights? Will I have a benefit from using non shadow area lights as fill lights(indirect shadow is ambient occlusion generated)?

12 December 2006, 01:05 PM
Hi there;

My problem is the disapearing Mental ray tabs in area lights..., all my lights have mr parameters BUT area lights, someone mentioned it earlier also, is there any fix for that?

A pic is better than nothing:

12 December 2006, 03:40 PM

12 December 2006, 06:34 AM
erm, i think I encountered that problem as well when I first installed maya 8. I uninstalled and re-installed it and somehow the problem went away.


12 December 2006, 09:17 AM
OK, Iīve reinstalled it but first I deleted all my old preferences and possible MAYA entries in my HD and now is working properly..., what a shame.

By the way, Are you guys happy with this release?

12 December 2006, 02:48 PM
If there wasn't mental ray 3.5... no not really, as far as I'm concerned !

One thing I doesn't like in particular are these windows, like Normals > Set Normal Angle. You MUST close the window in order to apply the setting, there is no proper option box ( no apply button that is) and imo that's totally counter productive, really regressive :eek: Looks like... er, you know... any standard Windows app :D

The multicore processed dynamics are cool tho... oh and it is quite stable anyway... few cool features... not worst the hurry for a release, we could have waited more for a better one !

12 December 2006, 08:55 PM
I donīt know much about that, I use Shelves for almost everything, I think thatīs what caused the arealights error! Ž_Ž

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