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I'm working on the donut tutorial, and got stuck in video 12 where you make the floating particles, managed to do everything correctly until the part where you make them rotate independently. I did everything as shown in the video as you can see in the following image:

What my geo nodes look like

but it isn't working, the particles aren't rotating.

this is my blender file:

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  • $\begingroup$ The reason your #frame driver wasn't actually returning the current frame, was that it was being put through an f-curve. (If you right-click > open up a Drivers Editor with the node selected, you can see it.) Unlike animation f-curves, which are time along the X axis and value along Y, Driver f-curves are expression value along X, and you own mapping of it along Y. Best way out: forget it, and use Scene Time , as Gordon has suggested. $\endgroup$
    – Robin Betts
    Aug 1, 2023 at 16:30

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I don't know what you've done to your particles... I see almost only spheres - and rotation is hard to see on spheres.

I created a new collection with cylinders to see the movement better. Turns out, your rotation setup does work, but very very slow. I've set the Math > Divide node to divide by 0.1 see at least some movement.

As it turns out, the #frame driver used for the animation is no longer working as expected, it is not putting out the frame number as value (as you can see in your screenshot, the current value is 0.916). The tutorial is using an older version of Blender.

Today you can use the Frame output of the Scene Time node to get the frame number.

scene time node

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  • $\begingroup$ Can you show which divide node you changed? $\endgroup$ Aug 1, 2023 at 14:46
  • $\begingroup$ @ThunderCoder The one to the right of the screenshot, the one for the random rotation, but I changed it back because as I explained in my answer, if you use the Frame output of the Scene Time node this is not necessary. The driver #frame does not work properly anymore, in your file it decreases slowly from 1.0 to some small value < 1. $\endgroup$ Aug 1, 2023 at 16:17
  • $\begingroup$ -tau to tau is a pretty silly range for random rotation, but maths was never a big thing in Andrew Price's toots, I guess :D $\endgroup$
    – Robin Betts
    Aug 1, 2023 at 16:53
  • $\begingroup$ @RobinBetts Definitely not 🤣 But anyway, that wasn't the problem here... $\endgroup$ Aug 1, 2023 at 21:41

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