This allows specifying how many times per second an effect should be
triggered for a particle source instead of triggering the effect every
frame. This will allow modders to achieve more consistent particle
effects regardless of FPS.
The current particle system uses dynamic allocation of particle
instances for keeping track of particle instances. This adds unnecessary
overhead in case the code does not need a handle to this particle which
is the case in pretty much all instances.
The new non-persistent particles are stored in a standard vector without
dynamic allocation which should make the processing steps using this
vector much faster and allow better scalability in case more particles
are used by a mission.
Previously, the source orientation was always aligned to the world so it
couldn't adapt to a weapon that changes direction. This fixes that by
introducing a "relative" mode for source orientations that is enabled by
default and disabled if the direction is set explicitly.
asarium