Boid Particles do not work with Cake Particles

[najibbasirun]

Hello,

I need to finish this project to use it as an AR project so your add on has helped a little bit but the rotarion of the boids I cant just get it to be correct. So Im trying to make a swarm of fish and it should lead the animation with its head but with your add on its just floating around like dead fishes instead :( pls help

when i turn on object rotation it still gives the same result in render setting
with cake particles:
https://github.com/user-attachments/assets/a21198bc-6d04-4b38-a4bf-8e0c20a609cf

how its supposed to look like
https://github.com/user-attachments/assets/510cec68-c0f1-4a82-9caf-1cba8763a2ed

[Scaryplasmon]

hello there @najibbasirun
thanks for reporting your issue here!

I did not encounter this issue before though, and when testing myself a simple boid simulation everything seems ok on my end
here's a video

boidsim.mp4

As u can see at the end of the video i overlap the particle simulation with the baked objects particles and they match perfectly.

I think to help u debug this better i need at least the details of your simulation or your .blend file

[najibbasirun]

hey, thanks for replying!

yes it works, and i have the boid brain to follow leader and it does even do that too but my fishies are not facing the right way its doing exactly what it is doing in the example video youre showing, floating around idly instead of being moved with its head foward. like how fish should swim! I hope you understand what I mean 😓

the orange fish is the baked one which doesnot overlay perfectly

[Scaryplasmon]

ok i think this is the actual issue
if the fishes don't overlap then there must be some issue with the rotation of the fish object you're baking in.

have you tried to check the object rotation checkbox in the particle system settings under the render tab?

or see how the position/rotation of the fishes changes based on how you change the origin point location and rotation of the fish mesh

to specify what i mean, if the origin is not in the center of the fish, and your fish geometry points on a different axis compared to the conventional object axis.; this sort of issue might arise.

If you need me to debug this further please post a screenshot of your simulation settings and a picture of your fish geometry (paying attention that the object origin is visible), possibly also a picture of the axis origin (you should be able to visualize it by pressing Ctrl + . )

[najibbasirun]

here is the picture of my fish with origin and axis

this is what happens when i turn on and off for object rotation (before baking)

both end up doing the same result that Im having issues with which is floating aimlessly (after baking)

[najibbasirun]

https://github.com/user-attachments/assets/2bb9399e-7bf0-4503-9ae9-180b299ce438
here is a video

is there a way to turn off object rotation in the add on itself (the coding) because it seem to work when I check off object rotation before baking?

[Scaryplasmon]

Thanks the video was really helpful! Also beautiful school of fish! So glad someone is using cake particles for a project like this!

yes there is a way to turn off object rotation in the addon itself, you would have to run the addon code and in case i can help you do that as last resort

the thing though is that would not be a fix if i understood your simulation correctly, you need the particles to rotate during the simulation am i right?

also if i didn't understood badly you said it yourself that if u check off the object rotation before baking it works right?
that means that the issue must lie in the object orientation to begin with. (even if from the picture you shared doesn't look like)

is there any issue with the results when turning off object rotation before baking? like would that result please you or do the fish swim badly afterwards?
if there isnt, then we're done just uncheck it before baking.

if instead they swim upside down or something else then maybe changing the mesh orientation accordingly might help.
(meaning u enter in edit mode and you rotate the whole mesh around its origin to manually fix this orientation issue, like this the object orientation will stay the same but the geometry will point in the right direction)

feel free to share more videos or snaps o your attempts, we're getting close to the root issue!

[najibbasirun]

omg youre right! fixing the orientation of the model in edit mode made it work!! (object rotation must be turn on) thank you so much!! Im so happy hopefully I get to see them swim in my uni AR project :D

[Scaryplasmon]

Glad you made it work! 💯
If you feel like it do share a video of your project when it's ready!
Would love to post this work on the cake particles page, crediting you, if you like!

Best of luck with your AR project! Happy Blending @najibbasirun!

[najibbasirun]

oh Id like that! once it is finish of course, right now I am having trouble exporting it into glb 😓😂

It only wants to copy the NLA strip of one baked fish animation and leave the rest...any tips? I think its my export settings Im not sure what Im doing wrong

[Scaryplasmon]

hi @najibbasirun, yeah it's tricky to export glb with the addon
I think it's so tricky that the next update i'll probably expose some default export option so that it can be done with one click

So glb/gltf is heavily optimized for armature animation rather than a lot of objects exports

for this reason when i tried i got the same exact results as you!

but i've find the right export settings,

• Select all the objects particles
• Check Selected Objects under the Include panel

• Go Under Animation tab and select Scene and Very Important uncheck Split Animation by Object

this should work just fine, but feel free to ask for additional help if it doesn't!

(The reason why this option breaks the export i think is because Cake Particles avoids performance issue by reusing the same object data for all the baked particles (a bit like a particle system does already))

Looking forward to see the project once it's done! 😸

[najibbasirun]

hi again @Scaryplasmon,

I dont have anyone else to ask about .glb export may I know if I can contact you further on how to export regarding on .glb settings? Im trying to export a flat plane with animated UVs and I tried a few settings and its not registering the animation of my UVs. Ive packed them into NLA tracks and it still does not want to read :(

I hope you can help as Im doing this all alone and my team is relying on me for the 3d aspect 😔

2025-08-25.23-17-39.mp4

[Scaryplasmon]

hi there @najibbasirun no worries! i understand how difficult it could be to not have someone to help you with this stuff. On this topic i recommend https://blenderartists.org/ where i was lucky enough to find some amazing people that taught me a lot and helped me when i was starting out!

To get to your question, not super sure but i really don't think you can export UV animations in .glb format! :(
That is actually a nice animation u got there, gg!
also where are you exporting? and how is your UV animation done?
Is it done with the UVproject modifier? Are you just animating the UV coordinates in the material? in both cases it's really impossible to get that out of blender through .glb export.

Depending on where you're exporting there are a certain amount of tricks that u can do.
first and easiest one of them all is doing a flipbook or animate UVs in the software you're exporting to.
Do let me know what u plan to do this or where you're exporting it cause usually this sort of tricks Must be replicated in the software in which they end up.

[najibbasirun]

Hello!

Yea Im learning the hard truth the glb does not support 2d sprites... but I did learn that a few people suggested on the blender stack that you can do one big long UV containing all of your sprites and animate the UV moving across the 3d mesh plane. SO the answe is animating the UV coordinates in the material. I followed a facial rig tutorial that suggested this and animated them by using keying sets.

2025-08-26.08-53-15.mp4

So thats what I did, I just dont know how to export it now with this trick

[Scaryplasmon]

hi @najibbasirun sorry for the late reply, very busy days of work these ones!

This is is exactly what i was talking about, great work!
unfortunately as far as i know glb cannot store this type of informations.

What are you planning to do with this glb? what is the the landing software in this case? are u exporting to unity, unreal, godot or something else? or is this gonna go directly onto some webgl renderer?

Depending on this there are quite a few things that u can do to export your animation

Mainly reimporting the Texture and Animating the UVs or to better say the shader in the software of export would have to animate the UV coordinates to make the UVs slide over the texture like you're doing in Blender.

So to Answer i do need to know the software of landing in this case! :) hope this helps!

[najibbasirun]

thats okay! Im using a webgl renderer mywebar.com by devar

youre once again right the webgl has a extension to input apng format which I never heard of but hopefully will make it work! woohoo!