dop pop attributes used by the solver to compute movement?

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Hi, I was wondering, which pop attributes does the dop-pop solver uses to compute movement, also what's their mathematical relationship?
I've got so far:
v
force
targetv
airresist


the reason is that I'm not sure about the targetv-airresist force v interactions and I'd like to build a boids based crowd system and mix the use of pop fields and pop wrangles where I further manipulate v directly.

Many thanks
http://www.lucavfx.com [lucavfx.com]
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Easiest way to find out what attributes are used is to set up a DOP net and look in the Geometry spreadsheet. You're certainly missing things like @mass and the various spin/orientation attribs.

Unfortunately (as far as I know) you can't dive into the multi solver at the heart of the POP solver to see how it does what it does, but it's probably going to be a collection of simple physics equations. Stuff like accel = force/mass, v += accel/timestep etc.

If you don't use the force attrib, you can manipulate velocity directly (much like the way things like POP Advect etc give you the choice of whether to advect by applying a force or by setting velocity).

And you could probably work out what the airresist / targetv stuff is doing by setting some attribs manually, then stepping to the next frame and seeing what's happened (though that's a little hackery)
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just dive into POP Solver, most of the math is visible inside
Tomas Slancik
FX Supervisor
Method Studios, NY
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