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pen_pen23
08-19-2004, 02:31 AM
if you make a box and reverse the normals, then turn off double sided,
then put a light outside the box and turn shadow casting on, the box will appear
as solid black in maya 5.0 and later yet it will be lit correctly in maya 4.5 and
before.

this means if a set is lit from outside with lights shining in, it will now render as
pitch black in maya 5 and 6, there doesnt appear to be any other solution than to
bake the lighting in 4.5 and then composite shadows into the set from the characters.

could someone try this and perhaps let me know if its just me thats going insane,
or if its alias aswell..

thanks

pen_pen23
08-20-2004, 05:36 AM
anybody ?

could someone possibly try this please just to verify that this is correct ?
has ANYONE lit a set with lights outside since version 5.0 ?!?

stallion151
08-20-2004, 05:54 AM
what happens if you don't reverse the normals and just choose opposite next to double sided.
(is there an opposite there, cant remember at the moment)

pen_pen
08-20-2004, 05:26 PM
a good suggestion, but alas . . the same problem . .

DOH

chocobo2k
08-20-2004, 07:38 PM
regarding your enquiry I've tried a poly cube with directional light outside with raytraced shadows turned on, Maya default render on Maya 6.01 so here is what If've got:

reversing the normal only ( Render normally )
reversing normals, double sided off ( Frontface culling) ( what do you expect! :scream: )
reversing normals, double sided off, opposite ( render normally )

without reversing ( normal )
without reversing, double sided off ( normal )
without reversing, double sided off, opposite ( again front face culling )

I think there is no problem with that, i don't know what about other versions of maya but it sounds obvious that we are hiding the faces that infront of camera by doing what you suggest :applause:

pen_pen
08-21-2004, 12:31 AM
chocobo2k thanks for doing that test,

its a little difficult to explain exactly what the problem is, so ive made a diagram

www.3dluvr.com.pen_pen/shadows.jpg (http://www.3dluvr.com.pen_pen/shadows.jpg)

plz let me know, where ur results similar to these ?

pen_pen
08-21-2004, 12:33 AM
i mean..

www.3dluvr.com/pen_pen/shadows.jpg (http://www.3dluvr.com/pen_pen/shadows.jpg)

jeremybirn
08-21-2004, 02:04 AM
this means if a set is lit from outside with lights shining in, it will now render as pitch black in maya 5 and 6, there doesnt appear to be any other solution than to
bake the lighting in 4.5 and then composite shadows into the set from the characters.
Build your set with a separate group for each wall, ceiling, floor. The walls can just be cubes, whatever, but also group fixtures, doors, windows, lights, etc. into those groups, so you can do light linking if you want to do a cheat like that with a shadow-casting light shining through a wall, floor, etc. I think this will do what you want, but also will support more complex fully decorated sets - you can even turn off primary rays visiblity on some of them to run the camera though while they still reflect.

-jeremy

chocobo2k
08-21-2004, 09:04 AM
well, the result i've got is just like the 1st picture which means that Maya 6.01 is behaving like Maya 4.5 in the example you have given and it is for sure not like Maya 5.0.

I hope this resolve the issue !

pen_pen23
08-23-2004, 03:17 AM
i think at this stage that re-lighting my set is unavoidable . . .

but thanks everyone for the replies, there've been some good ways to avoid this
problem in the future . .

pen_pen23
08-23-2004, 03:36 AM
i think at this stage that re-lighting my set is unavoidable . . .

but thanks everyone for the replies, there've been some good ways to avoid this
problem in the future . .

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