Label on bottle

[mervin]

I'd like to render a transparent bottle with a label on it. Is it possible for the label to be white on it's backside (what you see through the bottle) and have a texture of some kind on the front?

[dalomar_cg]

Re: Label on bottle

You'd have to set up two materials, one for the front decal...one for the back, and then throw those into a Skp2sided material. I haven't tried this though, so I'll give it a whurl and see what happens.

[mervin]

Re: Label on bottle

Thnx for the advice.

I tried it, but can't get it to work. The backside of the label stays the same as the front...

I tried turning off "Double sided" for just the front material and both front- and back materials.

Any more tips?

[Micha_cg]

Re: Label on bottle

Trivial solution - offset surface with a very tiny offset and a white rhino mat color?

[mervin]

Re: Label on bottle

Trivial solution - offset surface with a very tiny offset and a white rhino mat color?

Do you mean to use 2 surfaces outside my bottle, 1 for the backside and one for the frontside of the label? Or would putting the backside inside the bottle-wall be better... I guess I'll find out =) Thnx.

I also tried something else: offset the outer surface of the bottle 0.1mm to use as the label. When I render the label without the bottle, it looks good: the inside is white, the outside has my texture on it:



But when I render the label over the bottle, which has a glass-like material applied to it, the inside is no longer white, but has a texture on it.



Is this a bug? Maybe the bottle reflects the outside of the label, which shouldn't be possible?

[mervin]

Re: Label on bottle

Micha, I tried offsetting 1 surface for the inside (.05mm) and 1 surface for the outside (.1mm) and got this:



It's more work, but at least the inside of the label is white!

Where do I report bugs btw? Or will things posted in this forum be used by the development team?

EDIT: Doesn't seem to work to good with transparent area's on the label:

[Micha_cg]

Re: Label on bottle

No, it's not a bug, it's a feature.

If you don't use caustic, glass material block light from lights sources. If you have enabled GI caustic, than GI light should come through. But best you try the easiest way and enable "affect shadow" at the glass material. Now you shouldn't get a shadow at the inner diffuse material.

[dalomar_cg]

Re: Label on bottle

No, it's not a bug, it's a feature.

For some reason that explanation rubs me the wrong way ;D ...maybe a little rewording could be in order. "Its not a bug, its intended/designed behavior"

[Mauricio_di]

Re: Label on bottle

So Micha you need both "Affect Shadow" and Caustics, the one from the general option menu?

[Micha_cg]

Re: Label on bottle

So Micha you need both "Affect Shadow" and Caustics, the one from the general option menu?

I try to avoid to use caustic, because the longer render times. You don't need caustic, if you enable "affect shadow", because than the glass will act like an object with diffuse material and transparency only, without refraction of the "shadow" rays.

[mervin]

Re: Label on bottle

No, it's not a bug, it's a feature.

If you don't use caustic, glass material block light from lights sources. If you have enabled GI caustic, than GI light should come through. But best you try the easiest way and enable "affect shadow" at the glass material. Now you shouldn't get a shadow at the inner diffuse material.

When I mentioned "bug" I was talking about the inside of the label showing the outside texture when I put the bottle in it. You are talking about the rendering showing a greyish inside of the label?

So what about the texture on the inside of the label?

[Micha_cg]

Re: Label on bottle

Ah, I understand, your material show the texture at both sides, but should show no texture at the backside. Interesting. You could post the scene here or send an email with scene file to ASGvis.

[mervin]

Re: Label on bottle

I've made a new (simple) scene, it does the same:

http://www.hostfile.nl/files/3h0uqlp...ottle-v1.0.3dm

EDIT: Maybe this shows the problem more clearly (the inner tube has no texture applied to it):

[Micha_cg]

Re: Label on bottle

Looks like a bug. I found a workaround. It seems to be, that the look through the glass makes, that the backside is rendered as frontside. If you flip the normal of the label and interchange the front/back materials, than it works.

[mervin]

Re: Label on bottle

Looks like a bug. I found a workaround. It seems to be, that the look through the glass makes, that the backside is rendered as frontside. If you flip the normal of the label and interchange the front/back materials, than it works.

Thnx, I'll try the workaround.