Unwrapping a tire, keeping scale

Hey guys,
Have a look at the image below. The sidewalls are fine but how do I force the center rows to keep their aspect instead of tapering like that towards the seam?


I think the tapering is due to the fact, that you did not set the seam at the edge, therefore the cap of tire does not unwrap without any stretching. Place additional seams on the cap where the tire pattern starts.

Thanks hotzst! I’m not sure I got it though, I placed more seams cutting through the rows but there’s always some distortion… Any other ideas?

Any other ideas?
Attach your blend file. It’s impossible for anyone else to know where you have placed seams or any other useful things about your model.

You’re absolutely right, here goes:

tire.blend (1.85 MB)

Setting the unwrap to conformal and the subsurf modifier off gives the attached. In the unwrap options you can also select ‘Use Subsurf Data’ to overcome some of the distortion you’ll get with the subsurf

Attachments


tire1.blend (1.86 MB)

Thanks Richard. I’d already gotten similar results but thought it should be possible to have no deformations at all, I guess I’ll just fix those ends manually.

The ends aren’t straight on your model anyway so you won’t get a straight end on the unwrap, or put the seams higher up on the tire so there is less curvature in the unwrap.

Sure, but not straight doesn’t mean distorted…

i downloaded the last file and i can see threads in viewport

but cannot find any images in UV editor
also don’t see any threads on the mesh itself


so where are the threads coming from here ?

thanks

ok sorry my fault i see now from side view

but very difficult to see the small threads!LOL

thanks

Aaah! :slight_smile: Yes, in the beginning I was planning to do a worn tire since the car isn’t brand new :slight_smile: Meanwhile I realized that would mean a LOT of work in texturing and roughing up the rest of the car, but… oh well, it will be a new old car with used tires :smiley:

did you use the array + curve modifier to do it ?
which requires some stiching at then end but still works well !

i made a few small and big tires using that method
but always end up with high res model

would be nice to see a low res one using UV map for the threads
but might be possible if you make one segment for the tire with symetrical UV mapping!

salutations

you could take a photo of tire threads and make some normal or bump map which could then be re use as UV image texture too!

or even use the AO baking of your high res model and make a low res model
see cg cookies for baking video tut !

salutations