After The God Particle... Going on with some tests for the animation of an underwater scene, this time playing with particle system and forces in blender (with which I am not very familiar). The particle system I used to create this shoal of fish is set with a simple fish model (same as [Abstract aquarium](https://skfb.ly/6ypzL)) as render object. The fish particle system was set to a "**Boids**" physics, and tweaking parameters gave the unique fish a smooth movement. A **vortex force field** was then added to the scene to create the swirling motion on the particles. I also added a collision domain (as a cube) to make sure that no fish went outside of a specified volume, but it proved unnecessary... I still have to figure out how to properly export keyframed animations to a fbx file, as the only file I managed to obtain was a 120MB one (for a < 100 tris fish model). A python script which has helped me is [here](https://blender.stackexchange.com/a/7142), but it does not pass the export phase very well...