Tangent Arcs Component but with Outside Arcs

Hi Everyone,

I would like to define a tangent arc in grasshopper using two tangents and a radius like the current tangent arc component that already exists; however, this component only produces arcs on the inner sides between two circles. I would like to do the same thing but on the outer side of the two circles. For example, in the picture below, the blue arcs being the outside arcs and the red arcs being the inside arcs.

Is this possible? I’ve been exploring other options, but this would make my life so much easier right now.



I actually found a very nice discussion thread that I missed the first time I was googled for a solution. If anyone is interested, you can find it here.

I also took the solution from that thread and created a grasshopper script that should be able to take singular inputs or trees. It’s probably not perfect, and there’s probably a better way to handle some things, but it works for me!

Tangent_Circles_Exploded.gh (24.1 KB)


1 Like

Check this

tangent2cir.gh (4.9 KB)


P.S. I added a ‘Random Subset’ feature (pink group) to use a subset of the list of circles as a quick way of trying any two circles, to match your diagram. Then I found I needed to sort the circle segments differently (teal group).

This model implements two different methods, BiArc (piped) and BzSpan (white curves).

TangentCrvs_2022Feb9aa.gh (38.4 KB)


Oh this is a great option too! I’ll try to implement this cause the other approach I created using the other forum had some tricky parts with trees that I could easily take care of in python. The only problem though is that this takes in t parameters and not a radius.