Slower Velocity Control for Particle SOP?

Beginners
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Whats the easiest ways to control velocity of particles?

I want to make slower JPG particles fall down.

Right now my simple particle sop system is merging with a tex3 material (jpg’s) in the Geometry COMP, so the look/design is there, but the speed is waaaaaaaaaay too fast.

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Hey @bluewhale,

the initial velocity of particles is controlled from the embitters’ point normals attribute.
There are various ways of controlling this: either use the Point SOP and manipulate the normals value adjusting the nx ny nz parameters available after setting the Keep Normals menu to Add Normals.
Another way to gain control would be to fetch the normals from the SOP with a SOP To CHOP, do your manipulation in CHOPs and then apply it back to the geometry with a CHOP To SOP.

particles
particles1431×427 33.5 KB

In the example here, I’m actually fetching the point positions of the SOP and apply them back as normals - this way the particles radiate from the circle outwards.

Hope this helps
Markus

particles.tox (846 Bytes)

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@snaut Thanks 1000x for your help!

Yes it worked! I experimented with using the PointSOP to make all normals = 0, and now I can just use the ParticleSOP forces to control all velocities.

I’m surprised there isn’t a Velocity Node like in Houdini, nor more tutorials using PointSOP in the Particle pipeline. After heavy digging, I found the first tutorial mentioning PointSop buried inside:
THP 494 & 598 | Audio Reactive Particles | TouchDesigner by Matthew Ragan

Thanks again for your help!

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