Wish: adjusting mapping rotation without distortion


there is a strange effect - if I set the right ratio and than turn the mapping, the ratio isn’t kept and I get a distortion. Please change the code so that the set ratio remains constant, even if the texture is still being rotated.

Here an example:

It would be useful if you shared a file with the surfaces shown in your screenshots. I have a hard time figuring out what I am looking at by just using the screenshots.

Here a better example. I adjusted the repeat in one direction to 3 to get squares. Now, if turn the mapping the ratio get’s wrong. Looks like the rotation process is done at the wrong place in the UV manipulation order.

TextureRotationIssue.3dm (536.2 KB)

I found that it works like expected if I mix the UV manipulation methods. If I only add the turn per texture control than it works:

But if I edit both, repeat and rotation, at the texture options than I get the same problem:

I hope the code can be fixed that the user can simple turn a texture without stretching effect if he use one of this two places.

Since you’re using surface mapping that is kind of expected.

Personally I never use the XYZ Position, Size, Rotation, nor UVW offset, repeat, rotation in the texture mapping panel. I don’t know how to use them and how they affect the results.

I would instead use a planar mapping for this case and size and rotate it so that the texture is correct.

That said, @Jussi_Aaltonen is probably the person who can tell you more about how the controls in Texture Mapping work for a surface mapping.

The surface mapping is often the simplest and best way. For example if you use a dashed curve with piping for stitching seams. Only surfaces mapping works. It’s cumbersome to find the right repeat and rotation if both are not independent.

Screen Shot 11-01-23 at 07.52 PM

That sounds interesting. What do you mean by not being independent?

I think about it more and find it’s a general issue, not only surface mapping. For example at box mapping we have the same problem.

Here an example texture. I can’t use it 1:1, since it’s higher than wide. So I set x=1.3 and y=1 and now if I rotate the texture than the x:y ratio doesn’t work anymore. If I set 90° than I need y=1.3 and x=1. And if I set 30° than I need to fiddle around to find the right ratio.
Independent means, I set a ratio and than I can turn the texture like I want and the shown ratio is kept.

You can check my checker texture example - textures should be able to be rotated without changing the ratio.

You should realize that rotating the texture is happening in the UV space and as such will be affected by it.

You should keep the UV space as uniform as possible. If you create a planar mapping set it to say 1.0x1.0 or 10.0x10.0. Set the repeat in the texture to 1.3x1.0, and try rotating the texture. You’ll see that now the texture ‘aspect ratio’ stays as you’d expect. Divide or multiply the UV repeat by the same amount when you want to tweak the size of your texture.

Here a short video showing how it stays better under control with a uniform UV space:

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I did some more tests and it looks like the workflow is:

I wished it could be easier: simple set ratio at the mapping options and rotate. Maybe per switching to an other rotation mode so that the repeat is for the object UV and the rotation for the texture. Do you understand, what I mean?

Hi @Micha ,

Object texture mapping properties and the texture’s settings in the assigned material will work together. This provides flexibility when using the same material/texture on multiple objects. In this specific case, I’d use a Planar mapping method.

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Right, for this simple surface planar mapping works. But I can see I’m not succeeding in conveying my vision :wink:

Thank you for you effort.

Hi @Micha

The UVW offset, repeat and rotation values in the texture mapping section represent the final UVW transformation. In that final UVW transformation those 3 are always applied in the same order: first repeat, then rotation and last offset. So the last adjustment you make is not necessary applied last.

Surface parameter mapping is a bad choice because it is usually somehow stretched all around the object. And if the texture also needs adjustment then it might get tricky to do both adjustments with the texture mapping. In that case it makes sense to use texture adjustments together with mapping adjustments.

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