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Full Version: Bone: Bending around obstacles
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I started a conversation with Jose by email, but wanted to continue here in case anyone else would benefit from seeing it, since I don't see much here on bone trouble shooting.

My original problem was that all of my bones were compressing into position 0,0,0. Jose explained this was because parts of my model had scaling. 

Since I hadn't scaled anything in Blender or Unity, I tracked this down to Blender's default FBX export settings.

I've included the settings I needed to leave everything unscaled and make this work with the simulator, with properties I changed underlined.


Now the problem I'm facing is that I can't seem to tune things quite right. My goal is to allow the tentacle to deform around walls with an ik constraint that's controlled by a player. i.e. if my tentacle flows around a corner, it should retain it's shape as much as possible while bending to accommodate the corner.

I've tried only turning on bending, but this doesn't work well. Is this effect achievable with Obi Bones? I feel like I almost want to put a rope in the tentacle and just make new control points when it rounds a corner.

Also when coming up against walls, one of my bones start infinitely scaling. I can fix this by unchecking "stretch bones" but then I'm not getting much movement. 

I've included my example scene, thank you in advance!
(26-05-2022, 10:53 PM)pixelpax Wrote: [ -> ]My goal is to allow the tentacle to deform around walls with an ik constraint that's controlled by a player. i.e. if my tentacle flows around a corner, it should retain it's shape as much as possible while bending to accommodate the corner.

How are you implementing this IK constraint?

(26-05-2022, 10:53 PM)pixelpax Wrote: [ -> ]I've tried only turning on bending, but this doesn't work well. Is this effect achievable with Obi Bones?

If you disable stretching (stretch/shear constraints) then bones will stretch infinitely. Note this isn't the same as disabling "stretch bones" in the ObiBone component: this will simply keep the original bone scale/length intact, but the simulation will still constrain the length and relative position between particles.

The effect you're after is definitely doable using bones.

(26-05-2022, 10:53 PM)pixelpax Wrote: [ -> ]I feel like I almost want to put a rope in the tentacle and just make new control points when it rounds a corner.

Ropes won't work for this however, since they're unable to keep their rest shape and they don't model torsion. Both are required for a bone chain.

(26-05-2022, 10:53 PM)pixelpax Wrote: [ -> ]I've included my example scene, thank you in advance!

I see no attachments to your post. Make sure to click the "Add Attachment" button to the right of your attachment after loading/dragging a new attachment, otherwise it won't actually be added to the post.

kind regards,