Animation Update #2 – “We live as particles.”

Today I took the fish we created last week and started making particle effects to work with the mesh. As of yet this is in-complete because we hit a big problem which was that we couldn’t rotate the meshes based on movement direction, which theoretically the  ‘rotate mesh by velocity’ checkbox should be enabling. (I will return to solve this later.)

However the main thing we were testing was how the silhouettes played with the light, and it was a success!

As far as I am aware particle effect meshes can’t have animation applied, and the textured materials don’t look at all pleasant or doesn’t accept lighting because they are dynamic, however I managed to achieve some pretty cool effects within the limitations discovered;

  • A local vector orbit applied to the particles meant that the fish ‘jittered’ around their position in space, meaning that no singular fish was still for an extended period of time, helping to break up the sameness.
  • Randomizing values such as spawn position, size, rotation, colour and velocity meant that the shoal looked more believable.
  • Using our water shader material as the active material  for the mesh meant that I had control over the shoal’s Y and Z translation, also helped to break up the silhouette and to give the appearance of a tight shoal moving together.
  • Particle Effect meshes will be most effectively used above the player blocking the light or at some distance from the camera, making effective use of the depth of field modifier as to best show off the silhouettes and avoid the glaring issues with this technology.

Suggestions for improvements:

  • Larger turning circle, particle effect range & velocity based direction – ensures fish is always facing the correct direction.
  • Work out how to effectively implement vector point following / avoidance, simulates AI beviours based on particle effect world space.
  • Matinee the particle effect emitter and give particles a behaviour to move forward as a group, OR
  • Hide the particle emitter behind a rock or seaweed clump and set particle behaviour to move forward X units, with a lifetime of 10~ seconds. This will mean that there is a constant stream of fish moving through the scene.
  • Add more curves to the timelines of the particle effects to introduce behaviours such as rotation over time, velocity over time, colour over time – provides more visual variety.
  • Experiment with AI fish behaviour either for shoals or singular fish, it will be a lot more flexible and solve problems I have discovered with the particle effect technique.

Look at my particle effect gallery here on

 Ralph Waldo Emerson
We live in succession, in division, in parts, in particles. Meantime within man is the soul of the whole; the wise silence; the universal beauty, to which every particle is equally related; the eternal ONE.