기체 입자는 기체의 한 입자를 시뮬레이션합니다. 각각 입자는 개별적으로 추적되며 고유한 이름과 인자 4개가 있습니다:
- position: The X/Y position of the particle relative, to the center of the world.
- velocity: the velocity of the particle. Unit: meters/second.
- force: the force with which the particle is moving around.
- mass: the mass of the particle. This influences forces with which the particle interacts with other items.