The Particles to SDF operator can be used to convert input particles into an SDF grid.
Include this flow’s particles: when enabled, the particles in the same flow as this operator will be input into the VDB.
Integrate spin/velocity: when enabled, the same flow’s particles will have their spin/velocity integrated during the input process.
Normally spin/velocity integration happens for a particle at the end of the timestep. Therefore, in order to properly sync VDB data with particle data of the current timestep, spin/velocity must be manually integrated beforehand. Hence, the need for this setting.
Operation: controls which boolean operation will be used to merge the particle data into the VDB.
Use particle meshes: when enabled, each particle’s mesh will be input into the VDB, instead of simply considering the particle as a point with a radius.
When “use particle meshes” is disabled, each particle will be treated as a point with a radius (ie, a sphere).
Absolute radius: the radius of each particle will be set to a specific value.
Radius: the specific radius value.
Shape radius: the radius of each particle will be set to each particle’s shape mesh radius.
Scale radius: the radius of each particle will be set to each particle’s maximum scale dimension.
Multiplier: the multiplier to apply to shape/scale radius values.