Understanding history and parameters


I am trying to design a snail in Rhino (this animal illustrates my learning speed of Rhino (-; ).

Record History is on.

I designed a spiral (Curve menu), added a small circle around curve at the beginning of the spiral and a bigger one at the end.

I then used a sweep 1 rail to build a first approach of the snail. I now want to adjust it to get the final result I wish.

If I adjust the circles diameters, I perfectly see the history effect: the surface is redrawn in accordance with the modifications. Fine.

But when I try modifying the spiral, I can’t find out how to modify its parameters (step, end of axis, …). I can of course move its points, but Rhino creates too much points in a spiral for this method to be handy.

Did I miss something or is history not allowing access to parameters modifications?


Best regards,


No, in general Rhino “history” does not extend to curve creation, only surfaces. So you cannot go in and modify the input parameters of your spiral, the only thing you can do after creation is either transform it somehow (scale, etc…) or edit its control points.

If you need parametric access to the input parameters of curves and such the only free solution is Grasshopper. Otherwise there are paid plug-ins like RhinoParametrics that should allow you to do things like this (I guess, haven’t tested).


Hi Mitch,

That was my conclusion, and unfortunately, I was right.

Thanks for your comments.

I am wondering what’s simpler in this case: I reconstructed the spiral with less points, but when I move the control points, the circles do not follow, and I have a lot of manual adjustments. On the other hand, Grasshopper is a fantastic tool, but that’s another new world to explore.

Rhino is very powerful, but the lack of an actual history and of the ability to redefine a function is a real flaw.


FYI, I finally used Grasshoper. Not that hard, after all, and very impressive.

Thanks again.


And even fun ! :smile: