I have a 3DConnexion SpaceNavigator. It works very well for moving the viewport. Is there a way for it to place an object in the scene?

Is this something that can be accomplished via an addon? I am new to Blender, I'm delighted that the NDOF works out of the box, but I expect to be able to place objects using it. Would be much more intuitive than using a mouse.

So far I have setup a ViewOperator template and I can see that moving the 3D mouse yields a NDOF_MOTION event

def modal(self, context, event):
        v3d = context.space_data
        rv3d = v3d.region_3d

        if event.type == 'NDOF_MOTION':

blender console when moving the 3d mouse: <bpy_struct, Event at 0x000001B72D13B5F8>

I can see how I might write a script to move an object given the motion event. The problem is I can not find any way to get data from the event. I am expecting some translation/rotation vectors but those properties don't seem to exist on the Event object.

I believe the c implementation to move the viewport is here: ndof_orbit_zoom_invoke() in https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/space_view3d/view3d_edit.c

const wmNDOFMotionData *ndof = event->customdata;

There is no customdata on the event when it gets to my python script.

Which makes sense because there is no mention of any relevant data in rna_def_event() here: https://developer.blender.org/diffusion/B/browse/master/source/blender/makesrna/intern/rna_wm.c

  • $\begingroup$ Did you ever figure this out? We are very interested in using the 3D mouse to move models in the scene. $\endgroup$ – Madcowswe Mar 12 '18 at 2:03
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    $\begingroup$ @Madcowswe No, unfortunately. This caused me to lose interest in Blender and I've since moved on. $\endgroup$ – meta-meta Mar 16 '18 at 22:05
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    $\begingroup$ Stack Exchange isn't the only source of information! You can always drop by on IRC (FreeNode, channel #blender), join mailing lists, or chat at Blender.Chat. $\endgroup$ – dr. Sybren Mar 18 '18 at 9:08
  • $\begingroup$ @Madcowswe have you asked around on IRC? $\endgroup$ – meta-meta Mar 22 '18 at 15:23

Indeed, presently, there is no ndof_motion field in the python Event struct.

I checked in with Blender's Python API module owner @ideasman42 on the #blendercoders IRC channel, and he gave the thumbs up to expose this data with an added field. So I will try my hand at adding that. Assuming that all works out, it should then be possible to make your proposed addon.

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  • $\begingroup$ What's the status of this? Did you get it to work? How can I access it in python? $\endgroup$ – Jam Risser Nov 27 '18 at 15:45
  • $\begingroup$ @JamRisser Sorry I ran out of time for this project, so I don't think I will be able to do it any time soon. It didn't look very complicated to do this though, so I'd recommend doing it if you have the time. $\endgroup$ – Madcowswe Dec 1 '18 at 7:10
  • $\begingroup$ Could you give me a jump start by sharing your work with me? $\endgroup$ – Jam Risser Dec 1 '18 at 7:12
  • $\begingroup$ @JamRisser I never got to writing any code, but I remember that between the rna_def_event() in developer.blender.org/diffusion/B/browse/master/source/blender/… and the python event struct, I think that's the main path to get the data out by adding to those. There may be more to it, but then I would ask @ideasman42 on the #blendercoders IRC channel. $\endgroup$ – Madcowswe Dec 5 '18 at 0:23

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