Boundary handling is performed in particle-based simulation. Slab cut ball processing defines the boundary volumes for interaction with particles in particle-based simulation. The slab cut balls are used for collision detection of a solid object with particles. The solid object may be divided into a plurality of independent slab cut balls for efficient collision detection without a bounding volume hierarchy. The division of the solid object may be handled in repeating binary division operations. Processing speed may be further increased by determining the orientation of each slab cut ball based on the enclosed parts of the boundary rather than testing multiple possible orientations.