Inherit Velocity module
This module controls how the speed of particles reacts to movement of their parent object over time.
Using the Inherit Velocity module
This module is part of the Particle SystemA component that simulates fluid entities such as liquids, clouds and flames by generating and animating large numbers of small 2D images in the scene. More info
See in Glossary component. When you create a new Particle System GameObjectThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary, or add a Particle System component to an exiting GameObject, Unity adds the Inherit Velocity module to the Particle System. By default, Unity disables this module. To create a new Particle System and enable this module:
- Click GameObject > Effects > Particle System.
- In the InspectorA Unity window that displays information about the currently selected GameObject, asset or project settings, allowing you to inspect and edit the values. More info
See in Glossary, find the Particle System component. - In the Particle System component, find the Inherit Velocity module fold-out.
- To the left of the fold-out header, enable the checkbox.
API
Since this module is part of the Particle System component, you access it through the ParticleSystem class. For information on how to access it and change values at runtime, see the Inherit Velocity module API documentation.
Properties
For some properties in this section, you can use different modes to set their value. For information on the modes you can use, see Varying properties over time.
| Property | Function |
|---|---|
| Mode | Specifies how the emitter velocity is applied to particles |
| Current | The emitter’s current velocity will be applied to all particles on every frame. For example, if the emitter slows down, all particles will also slow down. |
| Initial | The emitter’s velocity will be applied once, when each particle is born. Any changes to the emitter’s velocity made after a particle is born will not affect that particle. |
| Multiplier | The proportion of the emitter’s velocity that the particle should inherit. |
Details
This effect is very useful for emitting particles from a moving object, such as dust clouds from a car, smoke from a rocket, steam from a steam train’s chimney, or any situation where the particles should initially be moving at a percentage of the speed of the object they appear to come from. This module only has an effect on the particles when Simulation Space is set to WorldThe area in your scene in which all objects reside. Often used to specify that coordinates are world-relative, as opposed to object-relative.
See in Glossary in the Main module.
It is also possible to use curves to influence the effect over time. For example, you could apply a strong attraction to newly created particles, which reduces over time. This could be useful for steam train smoke, which would drift off slowly over time and stop following the train it was emitted from.
Unity calculates the emitter’s velocity in one of two ways:
* Based on the velocity of an attached RigidbodyA component that allows a GameObject to be affected by simulated gravity and other forces. More info
See in Glossary component
* Based on how far the Particle System’s Transform componentA Transform component determines the Position, Rotation, and Scale of each object in the scene. Every GameObject has a Transform. More info
See in Glossary travelled during the current frame
To specify the method Unity uses, see the Main module’s Emitter Velocity property: