9.5.2

390 • CHAPTER 7
OBJECTS MENU • PARTICLES • 391
Rotation
Rotation imposes a velocity vector in the XY plane of the modier that is always tangential to a circle
whose radius connects the particle and the modier’s Z axis. This rotation occurs around. The Z-axis
of the Rotation modier. For an interesting effect, place the modier with its Z-axis parallel to the
direction of the starting point of the particles. This will create a spiral-shaped helical movement.
Attribute manager settings
Object Properties
Angle Speed
Gives the rotation speed of the particles about their Z-axes.
Particles may enter the rotation object on faces with normals that are not aligned to the modier’s
Z-axis. However, half of the surface area on those faces have rotational vectors that will cause the
particles to rebound away from the rotation modier.