Edit Pivot of 3D Connected Geometry

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Hello,

I used to work a lot in Maya with mutiple objects that I aligned to each other. To do that I typically manipulated the pivot of one object and then snapped it to a vertice of another object. I'd like to do this in Houdini as well, but I'm having trouble with it. When I create multiple objects within a container, I am unable to modify their pivot manually. Tpyically I'll want to modify pivot and then snap it to one of the points of the object. However, I seem to be unable to manually manipulate a pivot of an object inside a container when I have selected the object with the 3D Connected Geometry setting.

Am I overseeing something or is this approach just not suited for Houdini?

Edited by JohannesKristmann - Oct. 3, 2016 16:22:45
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Something like this?

The boxes corner ( point number 7 ) follows the spheres y pivot. The rest of the box follows too.

Did you also want only the corner point to move/follow while the rest of the box stays the same? I beleive and edit node added could do the trick.

And perhaps a bit of a digression if you want to get a bit more ‘under the hood’ you might want to look a vex - this guy covers an example of doing rotations around a pivot.

http://www.tokeru.com/cgwiki/index.php?title=HoudiniVex [tokeru.com]
Edited by BabaJ - Oct. 4, 2016 17:09:36

Attachments:
Object Corner follow pivot.hiplc (50.8 KB)

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Ok…so..I played with it for a bit..no..edit node isn't it…I used a combination of group and transform node.

Mind you I only did the work for the y axis of pivot point.

If either the sphere or box moves in the y direction the corner of the box will follow where the pivot point is ( in this case just the y value of the pivot point).

Also, there are many other ways to do this. Maybe someone can chime in and show a more simpler way?
Edited by BabaJ - Oct. 4, 2016 17:32:58

Attachments:
Object Corner_Only follow pivot.hiplc (56.3 KB)

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This kind of thing takes a little more work to set up in Houdini, but once set up it's set up and doesn't break.

Here are some orbolt assets that simplify this task https://www.orbolt.com/asset/AlexeyVanzhula::rebound [orbolt.com] https://www.orbolt.com/asset/AlexeyVanzhula::alignBB [orbolt.com]

I also attached a hip file showing some basic pivot editing and translation. The bbox() expression and local variables can be substituted with point() instead.

Attachments:
AlignedBOxes.hiplc (52.4 KB)

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