The Spin Operator produces a dynamic effect that usually occurs when an object is experiencing a force that has an offset from its pivot point. This also includes objects sliding on a plane, since they too can create rotational motion around any axis.

ON - (Bool) This input data stream determines whether the operator is considered 'on' or 'off'. You can connect other operators to this input channel such as a Bool Helper to activate/deactivate the whole operator.

Time - (Time) This input data stream is used to define the local time for the operator when the user wants to override the default system time.

Particle - (Particle) This input data stream reads in the currently selected particle group that is to have its particles be affected by spin forces. The data stream MUST be connected and will be highlighted yellow if it is not.

Rotation - (Rotation) This input data stream sets the absolute rotational value of the particle. The rotation is performed around the axis selected below in this operator.

Attack Time - (Frame) This input data stream is used to override the Attack Time spinner value.

Spin Time(s) - (Scalar) This input data stream is used to override the Spin Time per second spinner value.

Spin Time Variation - (Scalar) This input data stream is used to override the Spin Time Variation % spinner value.

Phase - (Angle) This input data stream is used to override the Phase deg. spinner value.

Phase Variation - (Scalar) This input data stream is used to override the Phase deg. Variation % spinner value.

Bearing Friction - (Scalar) This input data stream is used to override the Bearing Friction spinner value.

Speed Dependence - (Scalar) This input data stream is used to override the Speed Dependence spinner value.

Size Dependence - (Scalar) This input data stream is used to override the Size Dependence spinner value.

Axis Type - (Integer) This input data stream takes an integer value that represents the Type of Axis that will control the particles' spin. Valid input values are 0 through 2, where:

• 0 = Random
• 1 = Direction of Travel
• 2 = User Defined

Axis - (Direction) This input data stream is used to override the three Axis spinner values. This value is only used when the Axis Type is set to User Defined.

Axis Variation - (Angle) This input data stream is used to override the Variation deg. spinner value.

No Operator Outputs.

Use this rollout menu to control the Spin effect of a particle.

Attack Time - Increase this spinner's value to give the particles a little bit of reaction time before they reach their full spinning speed. The value is set in frames.

Spin Time [s] - This parameter sets the amount of time it takes to do a full 360 degrees rotation for each single particle. For example, a value of 10 for example will make the particle do a single revolution in 10 seconds. Lower values will produce faster spin rates, while higher values will create slower spinning.

Variation % - Increase this value to assign different spinning speed rates to each particle. Higher values will add more variety to the spin speeds between particles.

Phase deg - This spinner sets the starting angle for a particle. Usually the spin of a particle starts at a 0 degree angle. You may shift this starting angle with the help of the Phase parameter.

    Variation % - Increase this value to assign a different phase value to each single particle. Higher values will add more variety to the angular phase when particles are born.

Bearing Friction - This spinner value sets the time it takes until the particle starts spinning.

thinkingParticles is able to simulate real world effects like spinning particles or objects. Imagine an exploding car - heavy parts (like the engine block) need higher energy values to get accelerated by the blast wave while smaller parts such as doors, screws, tires, debris and so on receive a much higher angular acceleration from the same blast. Therefore, the two Dependency types like you connect the spinning speed of a particle to the size of the particle or even the actual particle speed. The idea behind this feature is that usually bigger parts (size) are heavier than smaller parts and also faster moving particles are lighter than slower moving particles.

Speed - This spinner controls how much dependence the spin speed has on the velocity of the travelling particle. Faster particles will spin faster than their slower moving counterparts. A value of 1.0 will make the spin speed fully speed dependent. All values higher than 1.0 will act as a multiplier for the spin speed dependence.

Size - This spinner controls how much dependence the spin speed has on the relative sizes of the particle. Smaller particles will spin faster than their larger counterparts. A value of 1.0 will make the spin speed fully speed dependent. All values higher than 1.0 will act as a multiplier for the spin speed dependence.

Choose the spin axis that you want to use for your DynamicSet from this drop down list.

Random - Choosing this option applies a random axis to each particle as it is born for spinning.

Direction of Travel - Choosing this option creates a spin axis that is perpendicular to the direction the particle is traveling. This is good for things like bullets, where you want the particle to be spinning and not tumbling end over end. A good way to visualize the direction of travel is to select the particle Group in the Particle Group Tree View and set the display to Drops. This will show you the relative paths each particle is taking.

User Defined - If you need to set a specific spin axis for each particle, you can do so by choosing this option. When you choose this option, the three axis spinners become active so you can set the axis manually. By default, the particles rotate around their local Z-Axis (0,0,1). If you want to spin the particles around their Y-axis you would set the parameters to 0,1,0 and so on.

Variation deg - To prevent all particles from spinning around the exact same user defined angle, use this spinner to increase the angle variation.