Confused and frustrated with gumbnal losing orientation, and not being able to align it back,

Hi McNeel team,

Gumball drives me nuts because it’s very unruly and unpredictable, and I just made a video here showing you some of its issues. And I caught a few bugs along the way.

What I see here so far:

  1. Bug: Manual dragging (or manual start + numeric input) extrusion ball looses object orientation. This does not happen with totally numeric input
  2. Huge miss: _GumballAlignment does not have a Surface option, only a Object (this si what’s already broken and driving me to use this alignment tool!), or Cplane option. I can of course do a '_CPlane _Surface first, then run that Cplane, but that’s as wasteful and time-consuming as it gets. We really need a Surface option here.
  3. Broken design: There’s just no way to snap rotate a gumbal to be aligned to a snapable edge’s )or any other object’s) orientation. Ctrl-Clicking on the rotation handle of the gumball is only useful to free-drag it.

Can you guys please make this better?



Hi @gustojunk
If you have “Snappy Dragging” turned on in gumball options, it will behave as you would expect - letting you align the axis to whatever you point your snap to, instead of some arbitrary angle.
Another thing I’ve been wanting to ask (sorry for hi-jacking, but at least it’s related!), is why the oneshot osnaps can’t be used for relocating the gumball? That would more or less solve Gustavo’s problem #2, as he would be able to use onshot OnSrf.
TIA, Jakob

I think he must have it set to Snappy Dragging otherwise he wouldn’t have been able to relocate the Gumball origin and snap it to the Mid point.


  • I see this here to. It seems like depending on how you perform the Gumball extrusion, the alignment on the resulting extrusion stays “to object” or gets strangely set “to cplane”. I logged the bug: RH-61999.

  • I was able to repeat the issue when realigning the arc, it’s the mouse pick-point (as opposed to the arc end point) that aligns to the Osnap, but it seems to be random and I’ve been unable to repeat since the first time.

  • When you say we should have a Surface alignment option, can you give us more details? For instance, you’d like to select a closed polysurface and have the Gumball aligned to one of its surfaces? Something else?

Fair enough - never had that happen to me.

Yeah, again I saw it once and haven’t been able to repeat it. Slippery little bugs :-)!

aaaha… I think you are right Vanessa, snappy dragging is a very weird thing for me. I’m realizing that aware about ‘snappy dragging’ being enabled, however I’m never aware when it’s disabled. I think it’s because Rhino snapping still works and I see things snapping on my screen, yet the gumball movement do not snap to anything. I think I might have posted an earlier video with this exact same problem :man_facepalming:t4:. …I know I’m pretty dumb, but probably not a lot dumber that a few other thousands of Rhino users out there, so maybe this design can be improved?

Also, is there a way to quickly toggle snappy dragging on/off? with a macro to be assigned to keyboard shortcut/button. Trying to find, click in the little circle bubble (that its actually even invisible by default) is torture for fast workflows.

I played with this more and I’m realizing that in many cases you don’t even need to go to surface when the objects are prismatic. even Cplane to object does the job.

I’ll show you here how Gumbal to Object does nothing, compared to what it should do, that I can get iot to do it applying this macro:

'_CPlane _Object

'_CPlane _World _Top

Same could be done aligning Cplane to surface.

I made a video where I’m also seeing more bugs in Cplane default centering BTW, and I had to use the _Between command to center the Cplane origin. unless I’m missing something else here, this is not working well?

here’s the video:

and the Rhino file I’m using here:
better_align_to_object_gumball_gf_201226.3dm (214.7 KB)

please let me know if you have any questions.



I use this to toggle gumball snap:
-_Options O B S EnterEnd

very cool Peter!

I added _NoEcho to it, and in theory that should prevent The Matrix’s text on the command line, but in this case is not somehow.

_NoEcho -_Options O B S EnterEnd

So I have G + Space to Goggel Gumball, GG + Space to toggle Snappy Puppy


Hi @gustojunk ! Thanks for the video! This is what I have from this:


  • Gumball Object alignment on Breps (eg: a box) is weird, RH-62091
  • Setting the Cplane to Object (or Surface) then configuring the Gumball Alignment to Cplane (on a Brep), algins the Gumball arrows to the Cplane axis but locates the Gumball Origin in the center of the bounding box of the Brep as opposed to the center of the object, RH-62092


  • Extrusion bug is fixed in Rhino 7.3, RH-61999


  • Have an added Gumball alignment option to align the Gumball to an object’s sub-object orientation, RH-62093


  • To set the Cplane to the center of the surface, try the using the Center osnap as opposed to the Between option. See clip.
    Cplane_Srf - Center Osnap

Hi @Vanessa, thanks for the bug reports.

Re: suggestion of using center, the geometry we are usually modeling is not as simple, or prismatic as I showed you in the video. The simplest it could get is having planar faces, but rarely faces where there’s an implied center that the Center Osnap understand. Unless you want upgrade that Osnap to Centroid or surface.

I’m pretty sure this is a regression. In the past the default origin used to be at the implied center, correct? Not it’s defaulting to the placement of your mouse click, which seems absolutely crazy to me.