What command to create a transition of curves between two curves?

I see V5 TweenCurves but where is this ability in V4 ?

If this was Macromedia Freehand I would use the Blend tool, choosing the number of steps between the two chosen curves, e.g. 5 would place 5 new curves evenly between two picked curves, there was also a logarithmic option to get a progression, all very useful for creating transitions between two curves of different colours etc. raster effects in a vector prog.

I wish to do the same in rhino, create evenly spaced new curves which form a transition of shape from one existing curve to another, forget the colour bit of course !

To have a choice over the number of curves between the existing that are created is essential.

To have a choice over the spacing (equal or logarithmic) would be nice.

How is this done ?

I have two curves in a 2D planar situation for my current need.

To be able to do this 2D and 3D would be good as well.

Tried it in V5, first curve asked for doesnt take on my yellow selection/highlight colour, remains normal so no visual feedback on whats been selected, is that right ?
2nd selection then sees both curves highlighted. No options for logarithmic but at least normal steps via N entry. Result doesnt get placed on ticked layer, is that right ?


Nowhere. TweenCurves is only in V5. There is MeanCurve in V4 IIRC, but that only places one curve in the middle and has fewer options than V5. The workaround in V4 is to create a surface between the two curves with something like Loft or Sweep2 and then extract the needed isocurves.

Yes, @pascal reported as a bug awhile back, still not fixed.

Yes. Requested as an enhancement awhile back, not yet implemented.


Hi Mitch,

With Rhino crashing on IE being used for CommandHelp (was it same for V4 ?) I am dubious about going over to V5 with such a vital project on the go.

I shall hop in there, do the command then revert back to V4 !

I hope the bug hasnt been overlooked,

and the ‘goes to tick layer’ as well.

In fact sometimes I dont want the result to jump layer, is there a way of toggling that to happen or not to happen in Rhino ?


Doesn’t happen here, never seen that. Is your computer/os up-to-date?

My request was for a command line option, so hopefully it will be implemented that way.


All Msoft patches up to date, java always updated.

IE is 6.0.2900 now that isnt !

I recall hanging onto it as the later version lost some function I used.

However as I havent used it a while guess Firefox is ok for me now so time I updated it.

WinXP sp3


Only five versions behind, not too bad… :smirk:

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