relax UV's

[freaq]

Hello dear people of odforce,

another question from me,

this time i'm having some issues with my UV's

I' trying to create a sort of rocky wall, using a vopsop displacement, but due to the way my object is mapped,

(an extended sweep as covered by the totorials from Kim Goossens on CMIVFX) I am having compression in sharp corners.

as per the example below,

I have tried to find some options for relaxing (they are even mentioned on the side FX site) and although I can smooth UV's

I cannot "relax" them based on their surface area. a plan could be to take the outside corners and use the measure SOP to measure the length of ech chordr,

but this would only work in this specific example... does anyone have a good idea how to do this in a way that can also be used in a more stable fashion.

as always all help is greatly appreciated.

[edward]

Maybe you could use UVPelt to stretch it out.

[freaq]

I have been using pelt, but it is completely remapping the UV's :s

I just need a relaxation however there seems to be no way to use the input UV's as a starting point.

any clues on how to do this, or another way of achieving that result?

I was previously contemplating using a point node to somehow determine the correlation between the size of each face and the UVsize, but failed to really visualise a solution...

seems this issue is harder then it seems :s

Edited November 27, 2011 by freaq

[edward]

Not sure. Have you tried the UVBrush SOP?

[edward]

Not sure. Have you tried the UVBrush SOP?

[CTEffects]

Here's an example I created that iteratively relaxes UVs with the wire solver in DOPs.

It probably wont work correctly on some seams, but you can constrain those problem-points in the solve or blend them back to their original UVs with an attribute.

In order to see what it's doing, bypass the timeshift SOP, view the "Swap_UV_and_P1" node, and press play on the timeline.

RelaxUVs_Final4.hip

Edited November 30, 2011 by CTEffects

[CTEffects]

Here's a slightly-altered example that might give better results.

RelaxUVs_Final7.hip

[CTEffects]

Okay, I've actually ditched the wire solver approach, and created a solver that is hundreds of times faster and gives better results, too.

This example file shows a method of iteratively solving a uv mesh relaxation using either a for-each SOP or a SOP solver. The solver will converge toward a solution where the average uv edge length and the average geometry edge length are identical, removing all UV distortion.

Also included is an OTL (and a hip file of it in use) for UV relaxation.

Note, this only works if the UVs are point attributes.

RelaxUVs_Better23.hip

RelaxUVs_OTL2.hip

RelaxUV.otl

[freaq]

Okay, I've actually ditched the wire solver approach, and created a solver that is hundreds of times faster and gives better results, too.

This example file shows a method of iteratively solving a uv mesh relaxation using either a for-each SOP or a SOP solver. The solver will converge toward a solution where the average uv edge length and the average geometry edge length are identical, removing all UV distortion.

Also included is an OTL (and a hip file of it in use) for UV relaxation.

Note, this only works if the UVs are point attributes.

wow I wasn't checking this threda for a while and BAM awesomeness!

thank you very much great work! checking it out now, really good looking at first glance!

Edited December 6, 2011 by freaq

[MagnusL3D]

Does not appear to work anymore