A flow field uses an array of vectors to control the movement of particles within.
It is especially useful for such things as chaotic movement, fluid movement, movement controlled by procedural formula and noise-controlled movement.
A flow field is an area of 3D space, divided up into a grid of smaller cubes or cells.
Each cell contains a parameter which is a velocity vector: a direction and speed of movement.
When a particle enters a cell, its direction is transformed to match that of the vector in the cell.
As it moves through the field it will enter other cells containing velocity vectors, that change its movement again; this will continue until the particle leaves the field.
The crucial factor in a velocity field is the arrangement of the vectors; these could be completely random or they could force the particle to follow a path.
xpFlowfield offers a number of ways to set these vectors.
General tab settings menu.
On, by default, this box can be unchecked to disable xpFlowField.