Object Properties

Velocity Type

This setting defines how the Field Force should affect the element (particle or object), i.e., how the velocity that the element already has (or lacks) should be affected. You can select from the following options:

Various modes for a horizontal initial velocity. The Field Force has a contant field layer with the direction Y=-1.

Add to Velocity

This is the usual behavior: the Field Force affects the element with its force and direction and sets the element in motion. A Constant Layer (with Y=-1) would force the element to accelerate increasingly faster in the direction of the floor (the horizontal velocity would remain constant).

Use this mode if you want to create realistic force effects.

Set Absolute Velocity

The existing element velocity will be completely overruled by the Field Force. No force will be in effect and the velocity will be controlled directly by the Fields.

A Constant Layer (with Y=-1) would let the element fall to the floor with a constant velocity (which can also be defined).

In conjunction with the Random Field (Noise), unwanted effects can result when used with this and the following option. Namely, effects can freeze. Noise Random Fields work best if they are mixed subltly with other Fields (or if they are used in a Volume Builder, see also here.)

Change Direction

The existing initial velocity will remain constant but the direction of the velocity will be controlled by the Field Force.

A Constant Layer (wth Y=-1) would let the element fall in the direction of the floor with a constant initial velocity.

This mode is, for example, suited for moving particles along a spline path with the speed of the emitter. To do so, position the emitter on the spline’s starting point.

Strength [-∞..+∞]

This setting can be used to create a velocity or force value, depending on the type of velocity selected.

Consider Mass

All objects controlled by dynamics have a mass. If this mass should be taken into consideration during acceleration, this option should be enabled.

Field

Note that only Fields/ Modifier Layers that can define a direction or use direction vectors can be used here effectively (the Shader Field or Colorizer, for example, cannot be used).

General information regarding Field lists can be found under Field.

Even though various blending options can be found here, not all are really useful in conjunction with vectors. Geometrically, the following make the most sense:

• Normal: Completely overwrites all subsequently arranged vectors.
• Add: Vectors can be added together. The beginning of the 2nd vector will be placed at the end of the 1st. The result is a vector from the beginning of the 1st to the end of the 2nd. This is, for example, how physically correct forces are added.
• Subtract: Subtracts the 2nd vector from the 1st, which reflects a negative addition or addition with the opposite vector.