Arc creation

Grasshopper
1

Hi, I was having a go at creating a shape with grasshopper that I could have some fine control over the curvature for evaluation without having to repeatedly rebuild it, but seem to have reached the limits of my knowhow.

In rhino I created some arcs from 2 points and the radius to control the curvature - in grasshopper there seem to be 2 options to make arcs but I seem to need a combination of both to get the same result.
Using the Arc command seems like a pain to constrain it to the start/end points, Arc SED has no control over the shape/direction of the arc created, unless I am missing something?

arcs
arcs543×927 12.1 KB
That’s an attempt with the SED arcs - it feels like i’m missing something obvious but can’t see for controlling the inputs/output arc.

Thanks,
Peter

2

Hi,

there is Arc CAB component in FabTools which does exactly that - creates an arc from 2 points and center.

Edit: Yeap, i see you want radius and 2 points as inputs, so it is not exactly what you wanted. But can be done like this or it should be coded, probably with just few lines…

image
image1272×591 59.9 KB

3

arc.gh (9.9 KB)

image
image1264×639 64 KB

4

If you’re aiming to rebuild/fit a curve to arcs, you might also implement this method:

5

It’s not often used, but if you want more control of the curvature Bezier Span might be worth playing with.

6
7

Thank you very much for the reply - that does seem to be working as I imagined!

1 Like
8

Thank you for the reply - that second version does seem to get the same result via a slightly different way. I am learning there are lots of ways to skin cats in Grasshopper!