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magneto

How to instance/copy animated geometry onto points that start when a point appears?

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magneto    142

Hi,

If you have animated point cloud, what's the best way to copy/instance animated geometry on these where the animation for each copy starts as soon as the point appears? Should I use TimeShift? For alembic files, I have to use abcframe? I thought maybe there is an easier way for this.

Because if I just instance them as is, the animation is already finished for all copies if I am at a frame that's greater than the last animated frame of the copied geometry.

 

Thanks :)

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Doum    19

Hey magneto,

 

There is a string attribute called instancefile(I think point to files written on disk) or instancepath(point to geo node inside houdini) which can be set to the path of your geometry ie(instancefile): "/geo/myinstance.$F4.bgeo" and you could create an attribute for the time for each point start at there birth? ie /geo/myinstance.@time.bgeo. But I think it will be only visible at render time? It been a while since I've used instance sorry :).

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magneto    142

Thanks Doum. I want to use this for not just cached geo but also animated/keyframed geo in the network. So alembic, bgeo, and inplace animated/keyframed all require different approaches.

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rich_lord    161

Here's one way to deal with keyframed data. Its pretty cumbersome. I bet with a bit of thought it could be made cleaner.

The copy chop lets you splat an animation down at any time another channel goes above a threshold. I've attached an example.

Heres how it works:

When the points appear, they get an int attribute just for that frame. i@just_appeared = 1

That gets read into chops and used as a template to copy the animation.

 

trigger.hip

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