How to make an A3 sized UV space in 3DS max that doesn't stretch.

poopstick

Ok I need to change the UV texture space to an A3 ratio without the texture map becoming stretched.

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So if you see here, I want to change the width of the space to incorporate the unwrapped parts on the right, but when I change the width it stretches everything like this.

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MoP

UV space is purely described as a 0-1 numeric range. So even if you specify a different width/aspect ratio for the display of the UV space, the positions/values of all the UVs are still the same (think of it like a percentage - a UV point at 0.25 will still be 25% across the space, regardless of if it's square or rectangular).

What you can do to "un-deform it" (as I assume you want to print this, or use a scanned A3 image as a texture?) is scale down the UVs horizontally by the A3 aspect ratio.

A square is 1:1 (aspect of 1.0) but A3 landscape is 42:29.7 (aspect of 1.41 recurring, the reciprocal of which is 0.707). Therefore you can either use a UVW XForm modifier with a scale of 0.707 on the U axis, or you can use the transform type-in in the Edit UVWs window to scale the UVs down to 70.7% of their original width.

This will result in the correct aspect ratio. You can then continue to edit the UVs at this aspect ratio and everything should be ok!

Farfarer

A sized paper is 1:sqrt(2) in dimension ratios, which as MoP mentioned is 1:1.41 or thereabouts.

So unwrap everything into a UV area of (0,0) to (1, 1/sqrt(2) which is about 0.707). You should be able to print that out exactly onto any A sized paper.

If you want to put an A sized texture back onto it for some reason, scale the UVs from the origin by 1.41 in the "short" axis. Then your A sized texture will fit the 0-1 UV space with no stretching.

poopstick

Thanks for the responce, did not expect such a specific solution I kinda understand what you are both saying but having trouble wrapping (get it?) my head around it. I'll probably ask my buddy to take a look over this and help me tonight as he's a lot more technical than me. Thankyou!!

MoP

Re-reading my response, it was a bit fiddly. However it has the full explanation of why you'd want to do this:

• Add a UVW Xform modifier with a U scale of 0.707 before adding the Unwrap UVW modifier