RANDOM NOTES USED WHILE DEVELOPING DEMO:
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spherical coords:
x=psin(phi)cos(theta)
z=psin(phi)sin(theta)
y=pcos(phi)

polar coords:
x=rcos(theta)
z=rsin(theta)

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phase 0: explosion
cur x, cur y, cur z, phase
dest x, dest y, dest z, theta

generate dest by choosing random theta, and phi (x/y angle)

move from cur to dest at fixed speed
once reach dest, bump phase (set y coord of dest to zero)

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phase 1: falloff
cur x, cur y, cur z, phase
dest x, 0, dest z, theta   (NOTE: dest y = 0)

move from cur to dest at fixed speed
once reach dest, bump phase

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phase 2: spiral in
dr squared, dtheta, r, phase
end r, ?, ?, theta

choose end r
calculate r (distance to new dest)
choose random dr, dtheta

r -= dr, theta -= dtheta

once all reached dest, bump all phase
