Import animated objects into Rhino / Bongo ->possible?

… i need to import an animated flag into my project , is there any way to do this yet?

thanks for any feedback


Which way is your flag animated? Is it a video, an animated gif, a third-party 3D-object with animation data?

hello Luc, it would be an animated 3d object… at least that would be the plan…

Ah, I misunderstood “import”. I guess you just want to model a flag in Rhino and let it wave by means of Bongo, right?
Probably a Loft with History recording of Morphed curves will do the trick. Take a look at the Flying sample model ( for inspiration.
When you can give me an idea of the complexity of the waving (a video?) then I can give it a try.

A waving flag: not really Bongo’s core-business: nevertheless a challenge:

Flag.3dm (373.0 KB)

To start with I made a kind of whip lash using Morphing upon a kind of sinus wave - see Animation set ‘Step 1’ in the model. A double-click on the clapperboard at the top of the Animation Manager opens the Animation Sets dialog.

I used a fairly simple curve (few control points), shifted 3 copies of the base curve (for 4 phase) and used their control points as a reference while transforming the actual curve in Animation Mode. Phase 4 is a simple copy of phase 0, hence making the lash loopable.

In the ‘Step2’ set is a first flag-attempt. I made 2 copies of the waving curve and shifted around the keyframes (0,6,12,20,27 and 0,10,18,24 and 31). Both waves are enabled Looping. Thanks to the difference in length of the loops (27 vs 31) a kind of randomness in the combination of both is induced, giving only exact repetition past tick 837. Both curves then are used in a Loft with History recorded.
Remember: History recordings won’t update in the viewportdisplay when you ‘Play’ the animation. You should constantly press (not click) the next-frame-button on the timelineslider instead.

Not bad! The flag, however waving indeed, looks rather stiff. Specifically the end away from the pole which remains straight looks unnatural.

In ‘Step 3’ an additional curve is added in the middle (again based upon a copy of the base-curve). This will bend the free end of the flag. To enhance versatility some rotational animation is added to the curve (rotation of the curve as a hole is added to the morphing data of the control-points). The center curve is additionally scaled a bit.

PS In order to have the infinitely looping animated gifs above the discrepancy in the looping of the curve was eliminated. A proper rendered video of the flag in the model will look less repetitive.


wow, thank you for the effort!

i will try it out tomorrow…



hey Luc
How did you connect the surface to the animated curves.
I want to try to make a system of curtains that a wind flow through and I try to using this method …

Thank a lot.

The surface is created by using Rhino’s Loft command on the animated curves with ‘Record Histroy’ enabled (in Rhino’s statusbar at the bottom). It doesn’t matter what tick the timelineslider is at at the time.

Afterwards you can move the keyframes around (also create new ones) the to get the desired operation.

When you want to relocate the (animated) surface, move the curves but not the lofted surface - the surface will move along with the curves. Moving the surface itself would ‘break’ the History.

This ‘animated history’ technique can be employed with any command that supports History (Patch, Pipe, Revolve, Ribbon, Twist, Flow,…) by animating one or more of the elements involved.
It occurs – among others - in the following topics:

Unfortunately History Recordings aren’t redrawn when the animation is ‘Played’ (Previewed). You can get a (bit shaky) preview though by pressing and holding down left mouse button (not clicking) the right/left arrow buttons of the timeline slider.