Spline constraints

Edward_Goodwin

I'm looking to constrain splines within a drawing. I can't work out how to constrain the direction/length of the spline handle... Any tips?

Also, it appears that there are no spline handles for points except for the start and end points. Is that really true? How do I manipulate the length/angle of a curve within the spline? Surely this can't be the case otherwise it seems to me that splines are severely limited in comparison to other cad packages.

Al thoughts and (I hope) solutions gratefully received!

NeilCooke

Hi @Edward_12

In a sketch, you can constrain a spline handle using dimensions or constraints (between the endpoint of the spline and the endpoint of the handle).



There are no handles on spline points at this time (please raise an improvement request). Mathematically a spline with handles on inner points is actually two splines end to end, so you can do the same thing in Onshape, it's just not as quick.



Hope that helps.

NeilCooke

Hi @Edward_12

In a sketch, you can constrain a spline handle using dimensions or constraints (between the endpoint of the spline and the endpoint of the handle).



There are no handles on spline points at this time (please raise an improvement request). Mathematically a spline with handles on inner points is actually two splines end to end, so you can do the same thing in Onshape, it's just not as quick.



Hope that helps.

Edward_Goodwin

Thanks Neil. This is a useful little animation you've added. It's frustrating that it's not possible to do this in one spline as I need to create something which is effectively a wavy pattern over a non-symmetrical surface (hence I can't actually pattern a spline/curve). It means I'll need to create hundreds of individual splines and connect them together whereas in SW I could have done it with 12 and then simply constrained the handles... Hey ho. I'll make the feature request.