Geometry Nodes

Github would be pretty good for something like this!

For blender files?
best to go on gumroad, thereā€™s a large community of users there :slight_smile: This would lead to more users discovering your file

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I have a strange speed variation at a GN bicycle chain. For demonstration purposes i moved the smaller half-curve out of its place, so you can see how the chain curve is constructed. When i press play, the chain movement is variing from right speed to slow and back to normal. I imagine it could be because i pulled the initial curve circle apart, with two resulting segments between the two half circles, where the point density is near 0. Thatā€™s why i resampled the curve, but the behaviour is still there. Do i think it wrong, or is this an expected behaviour?

I have a suspicion that you are changing the length of the spline part, which is causing the difference in speed. But you are trying to discrete it, using the count, by this you only subdivide, without taking into account the length, so the problem remains. Use length accounting
Ok i checked
this approach itself is bad

I have tried both: count and length. No difference.

Yes, it looks like this is basically a flawed method for creating a chain.
This is more correct


https://cdn.discordapp.com/attachments/340195875399663617/919949948496265226/sdfhb.blend

That helped indeed with the speed alternating, but now i have a solid gap :laughing:


Your attribute transfer made me thinkā€¦ maybe you are close to the solution, but maybe transfering the IDs somehow? My brainā€¦

discard the rotation part of the curve
you only need a factor shift

Oh! Makes sense to animate it only once :slight_smile: Awesome help! Thx
ā€¦oh no! It doesnā€™t. Let me have a breakā€¦

I think it is an optical illusion similar to this. Why Do Wheels Sometimes Roll Backwards In Videos? - YouTube

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This behavior is very strange, why sometimes this works and sometimes not?

Can anyone provide an easy way to transfer attributes thought instancing, when objects touching and have a different count of vertexes?

Instances do not inherit the parentā€™s attributes at the moment.
try to do the transfer of the attribute by index from the vertices

Or you wait until tomorrow for a new build.
https://developer.blender.org/rBf5ce243a56a22d71830c8c131d736737613aaaa4

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Talk about customer service lol
While youā€™re there Jacques, how are users meant to nest instances ? is that supposed to happen automatically when instancing collections of collections ? Iā€™m still kinda vague on the concept

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Iā€™m mostly just curious, is this section in the manual helpful at all? Instances ā€” Blender Manual

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Iā€™m always preaching to rtfm and there I am not following my own advice. Thanks Hans. To be real, I thought this was some distant projectā€¦ so didnā€™t think of looking up the doc. Now I understand what this is about. So, mostly an optimization that avoids realizing instances whenever stuff is instanced recursively -if I understand correctly.

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Manual is clear enough. Although when I recreate the example from there the, spreadsheet only shows as many instances as there are spheres, but cones arenā€™t counted. This gives the impression that sphere and its cones are merged into a single mesh before being instanced on the plane. Is this a limitation of the spreadsheet or am I missing something?

The spreadsheet only shows the top-level instances. Ideally we would implement something like an outliner tree view to see the full tree of nested instances. Understandably that gets a bit complicated though.

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My current thing about nested instance is that I need the realize node to have level controls, otherwise onec you nest it, you cannot come back. I saw somewhere that there was a plan about this but I donā€™t know the details, hope we have that soon.

Are there already dates when we could expect to have mesh edit nodes like extrude, bevel or recalc normals? Knowing is better than patiently hoping. Of course i could do the mirrored mesh parts differently than just scaling along one axis by -1, but this way the nodetree is much nicer, soā€¦ please!

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