Need advise rendering a lobby

[3ddesign]

In past projects, I've faked the illumination from the window by using a Vray Plane Light (right hand image) but after looking at the actual built space (left hand image) I want to change my tactics on my current, very similar project. I have been trying to use Vray2sidedMtl for shear curtains and stained glass, illuminated by a sun or direct light from outside, but my initial tests have proven disastrous. I'm beginning to wonder if it is even possible to use two Vray2SidedMtls on top of each other. Would someone be willing to share some ideas how I can reproduce the effect of sunlight hitting a translucent art glass window covered by shear curtains? I'd be very appreciative.

Craig

Edit: The threads I've been looking at are http://www.chaosgroup.com/forums/vbu...ass#post309308 and

http://www.chaosgroup.com/forums/vbu...=stained+glass

I've also been reading the Vray2SidedMtl tutorial at spot3d and the material in the pyramid model.

[3ddesign]

I guess it was a fairly undefined and involved request. I guess I should narrow it down to a few specific questions. Here goes:

1. The real art glass window and shears shown in the image in the first post diffuses the sun and day light and throws a very soft light into the room. Is there an accurate way in Vray to replicate that or is using a Vray Plane Light the best way to go?

2. In my current project, I have a large arched window. I've tried using a plane light but since it is rectangular, it casts uneven light around the curved edges of the window frame. Is there a good way to replicate the soft light cast by an arched art glass window using a Vray plane light? I've tried using a large number of smaller plane lights around the edge, but it is still difficult to get the light to light the window frame evenly. Since in real life the sheer curtains are lit by the art glass window, the same problem exists by trying to light them evenly around the curved edges.

3. I have played around a little with a vray light material to represent the art glass and provide the light but haven't been able to get it to look right. Before I spend any more time down that path, is there someone who has tried this method that can shed some light on the matter (bad pun unintended).

Thanks in advance for any assistance.

Craig

[fourthand11]

We haven't used the 2 sided material so I can't help you with the curtains. As for the lighting, we've used the vray camera, sun/sky system with vray lights in the windows or just outside the windows with the skylight portal checked. This brings in the blue from the atmosphere quite nicely. Also not storing with irr map is heavier but alot nicer shadows.

[Aldaryn]

I think putting a translucent VRay2Sided shader into the windows, mapping that with your desired map accurately (by this I mean mapping the strength of transmittance, or simply building the framing), and putting a VRayLight in skylight portal mode just in front of it (inside the room, of course) pretty much makes sense.

This will work well, if you need trasparent windows too in your space, since you can illuminate this with a VRaysun from the outside and it will behave correctly.

If you want to add a curtain too, it's best to put the skylight portal light behind the curtain.

You can stack 2Sided shaders on top of each other, but than only GI will transmit light between them since, as far as I know, transmitted light is not taken into account when checking for direct hadows. (there is no "affect shadows" tick to fake this). But GI will do it fine.

Also, the skylight portal is not really necessary imo. In most cases you use 2Sided shaders for large diffusors, and VRay can handle those quite well even with lower GI accuracy.

Best regards,

A.

[3ddesign]

Aldaryn,

Using a translucent Vray2Sided mtl did the trick. It looks much more realistic than using a plane light or portal light. I really appreciate your response.

Craig