Obstacles are very useful entities within the Particle Flocker system. They are 3D volumes that particles will try to avoid by utilising Obstacle Avoidance steering, which in turn creates very interesting and intricate flocking simulations.
Obstacles are generally very simple entities with little to no setup, other than choosing their volume dimensions and position within the world. Once placed, particles will always try to avoid flying into obstacles if possible.
The Obstacle Separation attribute on the Particle Flocker node controls how far away from an obstacle’s surface particles will attempt to stay.
If this value is set to 0, particles will be able to get right to the surface of an obstacle without needing to react. If the attribute is given a value greater than 0, particles will attempt to stay outside of this extended separation distance.
Obstacles can use any of the standard volume types within Particle Flocker. You can read about these in the Volume Types section.
Obstacles can also make use of the Mesh Volume type. To create a mesh obstacle you will need to first select a polygon mesh in Maya and then use the Convert Selection To Obstacle button in the Obstacles Rollout.
Mesh obstacles work in the same way as standard obstacles, however they are more computationally expensive and will drastically slow down flocking simulations. It is recommended that you keep poly count low if you are using mesh obstacles.