Loft Mapping Problem

[Aldaryn]

A problem with the loft procedural mapping, that the mapping will depend on the "knots" (- and thus related to the initial vertieces of the path spline. ) Where the mesh is generated denser, the mapping will strech. This is because the mapping is not applied uniformly through the whole mesh, but a given number of segments will share a single map repeat.

My suggestion is, to apply an Unwrap modifier onto your racetrack, and correct the mapping by hand, by acessing the UVW space with the Edit button.... It won't be too hard, because the loft mapping has done the major part of the work, you'll only need to refine the size of "loft segments" in the UVW space.

- A.

[EricChadwick]

Add some width segments. With just the vertices at the outside edges of the track, the UVs have to interpolate all the way across. Anytime you have long trapezoidal quads, you will see these artifacts. In my experience, tweaking the Unwrap won't solve it alone, you will need more verts running down the middle of the track.

You might also consider using Editable Poly and the Erase verts function to clear out some of the extra detail in the inside of the curve. Erase helps preserve the UVs, somewhat.

[AndyG]

Thanks for the help - increasing shape steps does help a little, but the problem still occurs on the very inside of each curve. It's also far from ideal to increase shape steps anyway as this obviously has a huge impact on poly count (important as this track is for game use).

What does "you'll only need to refine the size of "loft segments" in the UVW space" mean please?

Thanks,
Andy

[EricChadwick]

Unwrap isn't going to help any. In this case you'll just be shifting distortion around.

I would try erasing most of the verts from the inside of the turn instead, then Unwrap. Might work.

In the end though, this isn't all that noticeable. It's a racing game right? Players will be zipping around the curve, and seeing it at an angle anyhow.

Cool article on Gamasutra about tracks btw. Worth a look.
http://www.gamasutra.com/features/20020626/hargreaves_pfv.htm

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