A particle system in PhysX contains lots of properties that are used to define the simulation behavior of a particle and its interaction with the surrounding objects. These properties can be classified on the basis of their mutability (changeability) when they are defined for a particle system.
The classification of properties on the basis of mutability is as follows:
maxParticles: It specifies the maximum number of particles allowed for a particle system
PxParticleBaseFlag::ePER_PARTICLE_REST_OFFSET: It is a flag for enabling/disabling per-particle rest offset