CGMatter
Free Lite version comes with only collider collection, density, and radius controls! Doesn't includes splash controls, direction, and cutoff!
Rain Simulator
Rain simulator is a light-weight setup for photorealistic rain. A fully procedural drag n' drop solution!
(blue/green for visual clarity in gif)
Simulate 100,000's (or millions) of particles in seconds! Solver has been optimized for scene performance and accurate collisions.
(blue/green for visual clarity in gif)
(blue/green for visual clarity in gif)
Control both the rain itself and collision splashes!
Documentation
Colliders (collection) - collection of objects for rain to collide with.
Z Cutoff (float) - z value under which rain will be automatically deleted.
Density (float) - rain particles spawned per area.
Size (float) - radius of rain particles.
Direction (vector) - direction of rain velocity.
Speed (float) - scales the direction vector.
Randomize (float) - add randomization to the direction.
Droplets (integer) - Number of particles generated on splash.
Lifespan (integer) - Average frame lifespan of splash particles.
Speed (float) - Emission speed of splash particles.
Installation
Install like any other addon. Drag the zip right into Blender and hit confirm. The rain simulator will show up in Shift + A > Mesh > Rain