Pufferfish: parallel tweens on surface (Twn2CrvsSrf) vs grasshopper tweens

Hi, I’m trying to use pufferfish Tween two curves on Surface component, however the tweens I get seem to have a slight increase in their spacing (see my image, surface on the right) - I’m trying to get a result like the one on the left, where tweens look more evently/equally spaced (I’ve used the standard tweens component and projected on the surface).

Am I missing something? Is there any reason why the pufferfish component is ‘increasing’ the spacing between tweens?


tweens_pufferfish_vs_standard_for_review.gh (62.8 KB)


Hi, well projection is kind of cheating (and won’t work this way on more complex surfaces) evaluating things on a surface is not a projection. Tweening on a surface is evaluating domains influenced by the surfaces UV spacing. You cannot compare a regular tween to a surface tween, it is apples to oranges.

Plug your surface into a Surface Points component to see how uneven your UV grid is (specifically how tight it is at the bottom and how open it is at the top).

You could project as well with Pufferfish’s regular Tween Two Curves and get the same even results.

If you want a more even division in this case a solution is to make your surface with Uniform spacing and as a Refit loft. This will give you evenly spaced UV’s. Here I make the surface by a Loft with loft options set to Uniform and Refit.

UnifromRefitTweenCurveSurface.gh (22.3 KB)


Hi @Michael_Pryor, thank you for a clear explanation -
I will refit my surface as you proposed.

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