How to change U V direction?

Rhino Rhino for Windows
1

hey,
I want to change the U and V direction. i only can find to change the NORMAL direction of a surface or to flipp it , but not the UV. anyone an idea?

thx

2

Hi,
Run the “Dir” command.

3

I was just prepared to post a variation of the question above.

I was wondering how to change the uv directions to get all possible combinations according to the picture. I am trying to do this in python in grasshopper.

Is the normal independent of the uv directions?

uv.png827Ă—425 85.2 KB

4

Changing the u,v directions will not affect your surface normal in 3d modeling space.

5

I still need to swap the uv’s as illustrated. If it is possible. Even if the normal is independent.

6

Try this:

proba.jpg798Ă—511 73.7 KB

surface.Transpose() will swap values of u and v.
To change the direction of either u, or v: get the domain of one of these (uvStart, uvEnd = surface.Domain(0 or 1)), then create a new domain but with reversed negative values of previous one (-uvEnd, -uvStart). Then reverse the domain in that direction (surface.Reverse(0 or 1)).
By this logic, you can achieve all upper combinations.
Check the attached files.
uv.gh (19.2 KB)
uv.3dm (74.8 KB)

7

Thanks for saving the day again. :smile:

8

thx for this advice…i tried it but ists sadly not solving my problem

9

Hi alxwu,
The upper grasshopper component works with no problem.
Could you attach your surface please?

10

It’s a nice command, but the fact that it doesn’t contain “UV” in the name forces me to Google this answer every few years when I need it… :laughing:

11

10 Years later, Ai tells me:

How to Check and Fix Directions:

  • Use the Dir command on both surfaces.
    • Red = U direction
    • Green = V direction

image

  • If the directions don’t match up:
    • Use SwapUV to switch U and V
    • Use Flip to flip the normal
    • Use ReverseU or ReverseV to flip just one direction