I can't get emissive material to work

[lciaccia]

Can anyone help?I am using vray1.48.89 and i can't seem to get the emissive texture to give off any illumination at all. It used to work fine in the previous version of vray. I think i've tried everything and no luck. Is there a bug that anyone knows about? Does anyone know of a tutorial for this version of vray?
thanks

[dkendig]

Re: I can't get emissive material to work

works the same way it always has worked. Make sure you have the physical camera turned off (or the intensity cranked up pretty high), turn off the physical sun, and render.

[dkendig]

Re: I can't get emissive material to work

nevermind... I can't get it to work either... I guess I should have tested before I posted!

[dkendig]

Re: I can't get emissive material to work

oh wait a second... it works. It's only showing up on the front side of the face, unless you check the option to make the emissive layer two sided. In our old product, we didn't give the user the option to make the emissive layer two sided, it was always set to two sided.

[lciaccia]

Re: I can't get emissive material to work

ok, i'm trying what you mentioned in both replies but still no luck. when i turn physical camera off the entire picture goes white as if it were overexposed. even tried keeping physical camera on and cranking up intensity to 50,000, no luck, and double sided on and off doesn't seem to change anything.
the view i am working on is an exterior view. Is it necessary to use the same material map in the emissive layer? anyways i've tried this with and without but not luck
also the file i'm testing this out on is a clean SU seed file so i haven't changed any settings yet. i'm a little confused.......
thanks for your help

[lciaccia]

Re: I can't get emissive material to work

i got it to work. i had to add the material map to the transparency option in the emissive layer.

[dkendig]

Re: I can't get emissive material to work

In a clean su scene:
1. make an object
2. make a v-ray material
3. add an emissive layer to the material
4. enable double-sided in the emissive layer
5. apply the v-ray material to the object
6. set the intensity to about... 200
7. render

You should see the emissive layer show up in the render (the object should just appear to be white.)

To add a texture to the emissive layer, you're going to:
1. apply a bitmap texture to the diffuse layer's color texture, so su will generate UV information for the object (silly sketchup issue, you MUST use a texBitmap for this to work).
2. position and scale the texture to your liking
3. set a texture for the emissive layer's color texture (preferably the same bitmap texture you used in the diffuse layer, assuming you want to use a texBitmap for this)
4. render

You should see the texture being used as the emissive color texture now. The texture is going to be kind of washed out though. The more intense the light gets, the more washed out the texture will be.

[dkendig]

Re: I can't get emissive material to work

oh whoops, you posted before I did, glad you got it working!