sk2p material problem

[gueu]

Hi everybody !

I have modeled a car and I would like to make a render with an hdri environment. The problem is that with a sk2p material (with a difuse 50% grey ont the front and a 100% transparent layer for the back) it don' t work: I have a big grey square on my render.
I have already checked the normals and tried to exchange front and back, it still the same result.
Does I have to do some special things to have a good result ? I work on rhino 4.0 with vista.

Thx for your answers a go to see my car on
http://coroflot.com/public/individua...970&sort_by=1&

[dalomar_cg]

Re: sk2p material problem

So I assume that you're trying to use the skp2sided material almost as a "shadow catcher" for the ground plane? I think Micha had found this work around, and unfortunately I haven't been able to try this one yet(I'll try it tomorrow if I get time). So hopefully Micha can chime in on this one. Beyond that I would recommend that you check to make sure that you have a SKP2sided material as opposed to the standard 2Sided because that could be the possible issue as well.

[Micha_cg]

Re: sk2p material problem

The first time I read he post I don't understand the problem. I'm not sure now, but maybe it helps: create two diffuse materials and set at one material the transparency color white. Now create a VraySkp2SideMtl (this name is a bug or? ) and link the two diffuse materials. Now, one side is transparent and the other not.

[dalomar_cg]

Re: sk2p material problem

Now create a VraySkp2SideMtl (this name is a bug or? )

Yea thats the actual name. There was some discrepancy between the V-Ray 2 sided and the SketchUp two sided. That was the best that Joe (or any of us) could come up with, so if you've got some suggestions that would be useful

[Micha_cg]

Re: sk2p material problem

I would call it "TwoSided" only and try to get both material in one. A little flag option to disable the blend factor could be good to jump between the two current kind of two side materials.

[gueu]

Re: sk2p material problem

thanks you very much for those responses. But what micha propose is exactly what I have done (but thx !!!). I used some tricks to get a shadow with photoshop but it don't look realistic.
Any other idea ? :'(

[Micha_cg]

Re: sk2p material problem

Shadow? My hint was for the magic-one-way-wall only. What do you want to get?

[gueu]

Re: sk2p material problem

well I think I have not well explained my problem !

I have modeled a car and I want to make a render with a hdri map in the background (puted in the option of vray, in GI settings). But I want to have the shadow of my car (due to the environment lighting of course) on the "ground" but without puting a visible surface, I just want a diffuse shadow, like if my car was in the street or anything else. I know we can do it in vray for 3dsmax, with a material called "shadow material" or something like this. If you don't understand again I will post an image to eplain my problem ;D

But thancks for trying to help me !!

[Micha_cg]

Re: sk2p material problem

OK, a shadow material isn't available. You could place your car one soft studio ground plane and assign a diffuse material with environment mapped texture of the env texture you used. So, the ground looks like the environment and the car is on the street or what your env map show.

[gueu]

Re: sk2p material problem

okay no problem I decided to model my own environment ! I hope it will be available soon in vray for rhino but you are doing your best.
Thanck you very much micha for help me so much !