Method
This node applies a constant velocity to the affected particles. This is typically used to make particles move in a regular, linear fashion, e.g. wind effects or repulsions.
The Mode attribute is used to determine if the velocity is directional with a random spread determined by the Spread Angle attribute, or if it is an attracting or repelling velocity generated from the effector’s position. The magnitude of the velocity is controlled by the Velocity Scale attribute and modulated by a random value which is constant per particle and weighted by the Randomness attribute.
The velocity effect is weighted by a falloff calculated using the distance from the node to the particle. The effect is at 100% up to the distance specified by the Inner Radius attribute, then ramps down to 0% at the distance specified by the Radius attribute.
| Example |
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| This image is taken from the “simple_rain.dfx” sample project. |
| Example Nodegraph |
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Transform
| Name | Description |
|---|---|
| Position X | Move its position along the x-axis in local space. |
| Position Y | Move its position along the y-axis in local space. |
| Position Z | Move its position along the z-axis in local space. |
| Rotation Heading | Rotate the object about the y-axis. |
| Rotation Pitch | Rotate the object about the x-axis. |
| Rotation Bank | Rotate the object about the z-axis. |
| Scale X | Scale along the x-axis. |
| Scale Y | Scale along the y-axis. |
| Scale Z | Scale along the z-axis. |
Inherit Transform Channels
Toggle which transform channels should be inherited. By default, all are on.
Attributes
| Name | Description |
|---|---|
| Velocity Amount | Scale the strength of the affectors velocity on the particles. |
| Spread Angle | Change the angle of spread for the particles. |
| Radius | Alter the outer radius at which the affector is no longer effective. |
| Inner Radius | Alter the inner radius up to which the affector is fully effective. |
| Randomness | How much randomness is added in the particles movement. |
| Mode | Choose what kind of velocity affects the particles. |
| Falloff Shape | The primitive shape used to calculate the falloff weight for the affector.
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| Life Effect Coeffs | How much the particles are affected by the affector at different stages of the particles life cycle. Values 1 and 2 are control points used to control a bezier curve between values 0 and 3. |
Inputs
| Name | Description | Typical Node Input |
|---|---|---|
| Velocity Node | A transform node that overrides the velocity direction and source position. | Null |
| Mask Node | Mask out areas that particles cannot spawn. | Image Plane |
| Affected Emitters | Choose which emitters can be affected by the affector. | Primitive Emitter |
| Procedural Falloff | Use the SDF values from a procedural system to dictate the falloff. | Procedural Root |
| Transform Modifier | Links all transform properties to the input node. | Null |
| Target Node | Always faces the x-axis towards the inputs anchor point. | Null |
| Local Transform Override | Override the transformation values of the node, relative to its parent. | Null |
Outputs
All nodes connected to this node are treated as if flowing to the parent node, and inherits any transformation changes along the chain.
