Add points to packed geo

[MargotDS]

Hello!

I am trying for a while now to add certain points to a packed mesh, I need the specific positions of those points on that mesh but I dont seem to find a way to merge them together. So in other words what I am trying to find is a way to pack an object with a specific amount and specific placed points and not just 1 point at the origin or centroid. What I want to accomplish is that the points follow a wire with a pointdeform and then bend the feather according to the wire simulation but now the points and the mesh are not "glued" together so only the points follow and the mesh stays stiff. 

 

Thank you for reading  

 

[StepbyStepVFX]

Hello,

Packed primitives (if this is what you are using), are just a way to encapsulate your geometry so that, precisely, you only manipulate it like a solid object, using only one point (and one primitive, that contains that point) to bear all the attributes required for a RBD simulation, for example.

So if you want to work again on the base geomatry, you have to « unpack » your packed object, with the unpacked node.

Why are you using packed geomtery ? Is it for simulation purpose ? For instancing ? Depending on that, maybe it will be easier to work only on the unpacked mesh. You can also use your sim and the attributes P, V and W from your packed prim and apply them to other meshes than the packed one (separate animation from the feather from you sim).

With more info on what you are trying to achieve, we may be able to help you more :-)

[MargotDS]

Hey! Thank you for the quick answer!

So why I packed is because my feather excist out +-4000 points (in "low poly") and I want to make a full feathered animal(over 10 000 feathers) with an animation and simulation. Or do you think there is a better way to prevent crashing my laptop?  

And in my head the simple solution would be if I could get the geomety of the feather but packed with only a certain amount of point that can follow the wire simulation(see picture) so what I am atually looking for is to add points on a fixed position to a packed geo. I am fairly new to houdini and I feel like I sometimes miss a simple solution because I just didnt know a certain node existed.

[StepbyStepVFX]

I understand better. You want to simulate all 10000 feathers using wire solver (each wire containting only a few points to represent a low version of each feather ?), and instance and pointdeform a packed version of a feather on each wire ?

If yes, I would then make the wire sim first, and afterward loop over each wire (divide and conquer : you replace memory problem by using more space on disk), pointdeform my highres feather and save it to disk (.bgeo), and use it later as a "packed disk sequence primitive" (File Sop setup on packed disk sequencet). And depending on your computer strength, to save time, I would do it by bunch of 1000 wires (you can handle 1000 feathers at a time ? 4 million points is not killing a good laptop), and you would reach 10 sequences of 1000 feathers that you just need to load later for rendering...

If not, if you want to only animate one template feather (but I doubt it if your animal is moving), it is even easier : save your animation of one pointdeformed feather to disk (.bgeo), and instance it on your animal through a File Sop setup on Packed Disk Sequence.

All apologizes if I make you loose your time and does not answer correclty / understand correctly your problem, but your this topic is quite interesting :-)

Edited April 25, 2018 by StepbyStepVFX

[MargotDS]

No I am superglad that you are willing to help! I will definitely try it out since I am making this for my graduation work so the more research I do the more the teachers like me  even if it doesnt work out it is the research that counts  

[StepbyStepVFX]

1 hour ago, MargotDS said:

No I am superglad that you are willing to help! I will definitely try it out since I am making this for my graduation work so the more research I do the more the teachers like me  even if it doesnt work out it is the research that counts  

Indeed, this is in this kind of situation that you learn the most ! Let me know if « divide and conquer » works on your problem.