Shouldn’t it be more like
particle.velocity -= gravity * deltaTime;?
(I always find it confusing when equations talk about ‘initial’ but actually mean ‘previous’.)
In which case that’s almost exactly what I’m doing with gravity in Physix,
except I’m doing it without the delta time, and I’m factoring in the object’s mass.
Accumulating the delta time and then using a fixed physics step instead tends to get more stable results, or at least according to what seems to be the holy book on the matter.
(Or just assuming that each frame is going to be close enough to 1/60s that it won’t really matter, as I lazily did.
There probably ought to be a coefficient of friction in there somewhere as well, but maybe that’s going overboard?
You’re attempting hair particles?