Forum: Carrara


Subject: Labels on transparent bottle duplicated on backfaces?

nyar1ath0tep opened this issue on Feb 18, 2002 ยท 14 posts


nyar1ath0tep posted Mon, 18 February 2002 at 12:01 AM

In the attached image, the bottle on the left has refraction turned on. It's not obvious that the texture is being duplicated inside the whiskey bottle, but with refraction off (on the right), you can see that the box mapping for the bottle shows on both the inside and outside. Same thing happens with cylindrical mapping; hiding or showing backfaces makes no difference. How do I prevent the texture from being duplicated (or showing through) on the inside of the bottle?

geep posted Mon, 18 February 2002 at 12:07 AM

Use a separate "object" ---> a 2 sided square for the label and apply the texture to one side only.

cheers,
dr geep
;=]

Remember ... "With Poser, all things are possible, and poseable!"


cheers,

dr geep ... :o]

edited 10/5/2019



nyar1ath0tep posted Mon, 18 February 2002 at 2:52 AM

Thanks for the tip, geep.
How do I wrap the label object around the bottle and position it right next to the glass?
In the case of Jack Daniels whiskey, it's a single piece of paper that goes all the way around.


geep posted Mon, 18 February 2002 at 7:57 AM

Create the new "label" prop from the bottle mesh and then increase it's size by 0.1%. Put it in the correct position and "lock" it to the bottle prop. cheers, dr geep ;=]

Remember ... "With Poser, all things are possible, and poseable!"


cheers,

dr geep ... :o]

edited 10/5/2019



nyar1ath0tep posted Mon, 18 February 2002 at 3:20 PM

If the bottle itself shows the texture through the backfaces, won't a prop created from the bottle also show its texture through its backfaces? That's why a two-sided square would be nice, but I don't know how to wrap a two-sided square around a spline or vertex object.


DotPainter123 posted Mon, 18 February 2002 at 8:34 PM

To create the square (or the label shape) copy the original object (it should be a vertex object). In the vertex editor, delete every thing from the shape except the polylines at the top and bottom of the label. Select those lines and move them up and down as appropriate to set the size of the label. Then scale the object in xy/xz/yz (only 2) dimensions between .02 and .1 inches (kinda depends on the original scale of the object but it should do it). This will allow the label to cover the original geometry. If possible, cut up the label geometry so there is 1 polygon for each side. Lastly, set the UV mapping mode to box front and that should do the trick. Hope that helps. .Painter


nyar1ath0tep posted Mon, 18 February 2002 at 10:18 PM

Yes, I tried that. It seems that any kind of mapping (box/flat, parametric, cylinder) and any kind of flat mapping causes the texture to either show through or duplicate on the inside of the opposite box face. I'm still hoping there's a way to do it with just the bottle. One other option - putting an opaque blank label between the bottle and the printed label - doesn't seem like working smart.


geep posted Tue, 19 February 2002 at 10:18 AM

Make the "label" a "two sided" object. Now, use the "group tool" (in Poser) to define (and assign) the front and back of the "label" object with different "material." Now you can put the texture for the label on the front of the "label" object, and leave the texture for the back of the "label" object ....... blank. ;=]

Remember ... "With Poser, all things are possible, and poseable!"


cheers,

dr geep ... :o]

edited 10/5/2019



nyar1ath0tep posted Tue, 19 February 2002 at 2:08 PM

Good idea, geep. I can probably assign groups easily enough, but how do I make a label that wraps around a bottle into a 2-sided object? I tried doing that in Carrara by adding thickness to the label, but it just replicated the problem that the bottle had, because the bottle was already a two-surfaced spline object. However, I didn't assign separate materials to the inside surface of the label in Carrara; I don't know how to do that.


DotPainter123 posted Tue, 19 February 2002 at 3:03 PM

I think you may be able to get around this by using the cubic or flat mapping option as opposed to the parametric mapping option. This allows you to select the side you want display the shader on and may allow you distinguish front from back on a "single" sided object. Other than that you may want to do hide back faces in the assemble room. Or try a uvmapper like lithunwrap, which allows you to do multiple sides, then load reload the uvmapped object into carrera along with the texture. You may need a front and back texture though. I know I have done this before, without too much hassle. I will get out that old project and see what I did. .Painter


geep posted Tue, 19 February 2002 at 3:14 PM

Remember ... "With Poser, all things are possible, and poseable!"


cheers,

dr geep ... :o]

edited 10/5/2019



DotPainter123 posted Tue, 19 February 2002 at 9:02 PM

I found my old project where I did the same thing you are trying to do. It follows the instructions I gave in my last post, which are to use flat mappings as opposed to parametric mapping. Select the appropriate combinations of sides (left/right, front/back ) based on the location of each label. (I think that the "0" under Whole Object next to apply to is the backface,however, I am not sure.) Hope this helps .Painter

nyar1ath0tep posted Tue, 19 February 2002 at 11:37 PM

Then the idea is to use separate flat (box) mapping for opposite surfaces in order to avoid the effect I got in my first attempt. Geep, if .Painter's method doesn't work, I'll summon up my courage, take a few shots of Jack Daniels, and give your method a try.


geep posted Wed, 20 February 2002 at 2:36 AM

Did an experiment using UVMapper Pro and a flat square.
Assigned facets to 2 sided.
Saved the model.

Started Poser and loaded the "object."
Used the group tool to assign different groups and "material" to the front side and the back side.

Note: this DOES allow for the front-side and the back-side to have different colors applied and renders correctly.

Using a different texture map for the front and back materials, "bleedthrough" was observed in both rendered and unrendered views.

That is, I could NOT get a clean (non-textured <--rear of label) when any texture was applied to the front of the label.

Conclusion:
To get a clean texture for the front and back of a "flat" paper type of object, it requires 2 flat objects placed very close to each other with separate textures applied to each one.

cheers,
dr geep
;=]

Remember ... "With Poser, all things are possible, and poseable!"


cheers,

dr geep ... :o]

edited 10/5/2019