Shape module reference

Explore the Shape module properties to define the volume or surface of particleA small, simple image or mesh that is emitted by a particle system. A particle system can display and move particles in great numbers to represent a fluid or amorphous entity. The effect of all the particles together creates the impression of the complete entity, such as smoke. More info
See in Glossary emission, and the direction of the start velocity.

Shapes in the Shape module

The direction of particle emission varies depending on the shape you choose.

Shape	Description
Sphere	Emits particles uniformly in all directions.
Hemisphere	Emits particles uniformly in all directions on one side of a plane.
Cone	Emits particles from the base or body of a cone. The particles diverge in proportion to their distance from the cone’s center line.
Donut	Emits particles from a torus. The particles move outwards from the ring of the torus.
Box	Emits particles from the edge, surface, or body of a box shape. The particles move in the emitter object’s forward (Z) direction.
Mesh	Emits particles from any arbitrary mesh shape supplied via the Inspector.
Mesh Renderer	Emits particles from a reference to a GameObject’s Mesh Renderer.
Skinned Mesh Renderer	Emits particles from a reference to a GameObject’s Skinned Mesh Renderer.
Sprite	Emits particles from a sprite shape supplied via the Inspector.
Sprite Renderer	Emits particles from a reference to a GameObject’s Sprite Renderer.
Circle	Emits particles uniformly from the center or edge of a circle. The particles move only in the plane of the circle.
Edge	Emits particles from a line segment. The particles move in the emitter object’s upward (Y) direction.
Rectangle	Emits particles from a rectangle. The particles move up from the rectangle.

Shape properties

This section details the properties for each Shape.

For some properties in this section, you can use different modes to set their value. For information on the modes you can use, refer to Vary Particle System properties over time.

Sphere, Hemisphere, Circle

Sphere, Hemisphere, and Circle have the same properties.

Property	Description
Radius	Sets the radius of the circular aspect of the shape.
Radius Thickness	Sets the proportion of the volume that emits particles. A value of 0 emits particles from the outer surface of the shape. A value of 1 emits particles from the entire volume. Values between 0 and 1 will use a proportion of the volume.
Arc	Sets the angular portion of a full circle that forms the emitter’s shape.
Mode	Defines how Unity generates particles around the arc of the shape. For information on the Mode dropdown options, refer to Mode dropdown.
Spread	Controls the discrete intervals around the arc where particles can be generated. For example, a value of 0 means that particles can spawn anywhere around the arc, and a value of 0.1 means that particles can only spawn at 10% intervals around the shape.
Speed	Controls the speed the emission position moves around the arc. Set this value to Constant for the value to always remain the same, or Curve for the value to change over time. This property is available only when Mode is Loop or Ping-Pong.
Texture	Selects a texture to use for tinting and discarding particles. Important: You must enable the Read/Write property of the texture to use it in the Shape module component. Use the Game Objects view in Project Auditor (Window > Analysis > Project Auditor) to find and fix similar issues across your project.
Position	Applies an offset to the emitter shape used for spawning particles.
Rotation	Rotates the emitter shape used for spawning particles.
Scale	Changes the size of the emitter shape used for spawning particles.
Align to Direction	Orients particles based on their initial direction of travel. This can be useful if you want to simulate, for example, chunks of car paint flying off a car’s bodywork during a collision. If the orientation isn’t satisfactory, you can override this property by applying a Start Rotation value in the Main module.
Randomize Direction	Blends particle directions towards a random direction. A value of 0 has no effect. A value of 1 completely randomizes the particle direction.
Spherize Direction	Blends particle directions towards a spherical direction, where they travel outwards from the center of their Transform. A value of 0 has no effect. A value of 1 points the particle direction outwards from the center. When Shape is Hemisphere or Circle, a value of 1 behaves identically to when the Shape is Sphere.
Randomize Position	Moves particles by a random amount, up to the specified value. A value of 0 has no effect. Any other value will apply some randomness to the spawning positions of the particles.

Cone

Property	Description
Angle	Sets the angle of the cone at its point. A value of 0 produces a cylinder while a value of 90 produces a flat disc.
Radius	Sets the radius of the circular aspect of the shape.
Radius Thickness	Sets the proportion of the volume that emits particles. A value of 0 emits particles from the outer surface of the shape. A value of 1 emits particles from the entire volume. Values between 0 and 1 will use a proportion of the volume.
Arc	Sets the angular portion of a full circle that forms the emitter’s shape.
Mode	Defines how Unity generates particles around the arc of the shape. For information on the Mode dropdown options, refer to Mode dropdown.
Spread	Controls the discrete intervals around the arc where particles can be generated. For example, a value of 0 means that particles can spawn anywhere around the arc, and a value of 0.1 means that particles can only spawn at 10% intervals around the shape.
Speed	Controls the speed the emission position moves around the arc. Set this value to Constant for the value to always remain the same, or Curve for the value to change over time. This property is available only when Mode is Loop or Ping-Pong.
Length	Sets the length of the cone. This property is available only when Emit from: is Volume.
Emit from:	Chooses the part of the cone to emit particles from: Base or Volume.
Texture	Selects a texture to use for tinting and discarding particles. Important: You must enable the Read/Write property of the texture to use it in the Shape module component. Use the Game Objects view in Project Auditor (Window > Analysis > Project Auditor) to find and fix similar issues across your project.
Position	Applies an offset to the emitter shape used for spawning particles.
Rotation	Rotates the emitter shape used for spawning particles.
Scale	Changes the size of the emitter shape used for spawning particles.
Align to Direction	Orients particles based on their initial direction of travel. This can be useful if you want to simulate, for example, chunks of car paint flying off a car’s bodywork during a collision. If the orientation isn’t satisfactory, you can override this property by applying a Start Rotation value in the Main module.
Randomize Direction	Blends particle directions towards a random direction. A value of 0 has no effect. A value of 1 completely randomizes the particle direction.
Spherize Direction	Blends particle directions towards a spherical direction, where they travel outwards from the center of their Transform. A value of 0 has no effect. A value of 1 points the particle direction outwards from the center, behaving identically to when the Shape is Sphere.
Randomize Position	Moves particles by a random amount, up to the specified value. A value of 0 has no effect. Any other value will apply some randomness to the spawning positions of the particles.

Donut

Property	Description
Radius	Sets the radius of the main donut ring.
Donus Radius	Sets the radius of the outer donut ring.
Radius Thickness	Sets the proportion of the volume that emits particles. A value of 0 emits particles from the outer surface of the shape. A value of 1 emits particles from the entire volume. Values between 0 and 1 will use a proportion of the volume.
Arc	Sets the angular portion of a full circle that forms the emitter’s shape.
Mode	Defines how Unity generates particles around the arc of the shape. For information on the Mode dropdown options, refer to Mode dropdown.
Spread	Controls the discrete intervals around the arc where particles can be generated. For example, a value of 0 means that particles can spawn anywhere around the arc, and a value of 0.1 means that particles can only spawn at 10% intervals around the shape.
Speed	Controls the speed the emission position moves around the arc. Set this value to Constant for the value to always remain the same, or Curve for the value to change over time. This property is available only when Mode is Loop or Ping-Pong.
Texture	Selects a texture to use for tinting and discarding particles. Important: You must enable the Read/Write property of the texture to use it in the Shape module component. Use the Game Objects view in Project Auditor (Window > Analysis > Project Auditor) to find and fix similar issues across your project.
Position	Applies an offset to the emitter shape used for spawning particles.
Rotation	Rotates the emitter shape used for spawning particles.
Scale	Changes the size of the emitter shape used for spawning particles.
Align to Direction	Orients particles based on their initial direction of travel. This can be useful if you want to simulate, for example, chunks of car paint flying off a car’s bodywork during a collision. If the orientation isn’t satisfactory, you can override this property by applying a Start Rotation value in the Main module.
Randomize Direction	Blends particle directions towards a random direction. A value of 0 has no effect. A value of 1 completely randomizes the particle direction.
Spherize Direction	Blends particle directions towards a spherical direction, where they travel outwards from the center of their Transform. A value of 0 has no effect. A value of 1 points the particle direction outwards from the center, behaving identically to when the Shape is Sphere.
Randomize Position	Moves particles by a random amount, up to the specified value. A value of 0 has no effect. Any other value will apply some randomness to the spawning positions of the particles.

Box

Property	Description
Emit from:	Chooses the part of the box to emit particles from: Volume, Edge, or Shell. The default value is Volume.
Texture	Selects a texture to use for tinting and discarding particles.
Position	Applies an offset to the emitter shape used for spawning particles.
Rotation	Rotates the emitter shape used for spawning particles.
Scale	Changes the size of the emitter shape used for spawning particles.
Align to Direction	Orients particles based on their initial direction of travel. This can be useful if you want to simulate, for example, chunks of car paint flying off a car’s bodywork during a collision. If the orientation isn’t satisfactory, you can override this property by applying a Start Rotation value in the Main module.
Randomize Direction	Blends particle directions towards a random direction. A value of 0 has no effect. A value of 1 completely randomizes the particle direction.
Spherize Direction	Blends particle directions towards a spherical direction, where they travel outwards from the center of their Transform. A value of 0 has no effect. A value of 1 points the particle direction outwards from the center, behaving identically to when the Shape is Sphere.
Randomize Position	Moves particles by a random amount, up to the specified value. A value of 0 has no effect. Any other value will apply some randomness to the spawning positions of the particles.

Mesh, Mesh Renderer, Skinned Mesh Renderer

Mesh, Mesh Renderer, and Skinned Mesh Renderer have the same properties.

Property	Description
Type	Choose where to emit particles from: Vertex, Edge, or Triangle. The default value is Vertex.
Mode	Defines how Unity generates particles around the arc of the shape. For information on the Mode dropdown options, refer to Mode dropdown.
Spread	Controls the discrete intervals around the arc where particles can be generated. For example, a value of 0 means that particles can spawn anywhere around the arc, and a value of 0.1 means that particles can only spawn at 10% intervals around the shape.
Speed	Controls the speed the emission position moves around the arc. Set this value to Constant for the value to always remain the same, or Curve for the value to change over time. This property is available only when Mode is Loop or Ping-Pong.
Mesh	Select the mesh that provides the emitter’s shape. Important: You must enable the Read/Write property of the mesh to use it in the Shape module component. Use the Game Objects view in Project Auditor (Window > Analysis > Project Auditor) to find and fix similar issues across your project.
Single Material	Selects whether to emit particles from a particular submesh, identified by the material index number. If enabled, a numeric field appears for you to specify the material index number.
Use Mesh Colors	Modulates particle color with mesh vertex colors. If mesh vertex colors don’t exist, this uses the shader color property `_Color` or `_TintColor` from the material.
Normal Offset	Sets the distance away from the surface of the mesh to emit particles in the direction of the surface normal.
Texture	Selects a texture to use for tinting and discarding particles. Important: You must enable the Read/Write property of the texture to use it in the Shape module component. Use the Game Objects view in Project Auditor (Window > Analysis > Project Auditor) to find and fix similar issues across your project.
Position	Applies an offset to the emitter shape used for spawning particles.
Rotation	Rotates the emitter shape used for spawning particles.
Scale	Changes the size of the emitter shape used for spawning particles.
Align to Direction	Orients particles based on their initial direction of travel. This can be useful if you want to simulate, for example, chunks of car paint flying off a car’s bodywork during a collision. If the orientation isn’t satisfactory, you can override this property by applying a Start Rotation value in the Main module.
Randomize Direction	Blends particle directions towards a random direction. A value of 0 has no effect. A value of 1 completely randomizes the particle direction.
Spherize Direction	Blends particle directions towards a spherical direction, where they travel outwards from the center of their Transform. A value of 0 has no effect. A value of 1 points the particle direction outwards from the center, behaving identically to when the Shape is Sphere.
Randomize Position	Moves particles by a random amount, up to the specified value. A value of 0 has no effect. Any other value will apply some randomness to the spawning positions of the particles.

Sprite and Sprite Renderer

Sprite and Sprite Renderer have the same properties.

Property	Description
Type	Choose where to emit particles from: Vertex, Edge, or Triangle. The default value is Vertex.
Sprite	Selects the sprite that defines the particle emitter’s shape.
Normal Offset	Sets the distance away from the surface of the sprite to emit particles in the direction of the surface normal.
Texture	Selects a texture to use for tinting and discarding particles. Important: You must enable the Read/Write property of the texture to use it in the Shape module component. Use the Game Objects view in Project Auditor (Window > Analysis > Project Auditor) to find and fix similar issues across your project.
Position	Applies an offset to the emitter shape used for spawning particles.
Rotation	Rotates the emitter shape used for spawning particles.
Scale	Changes the size of the emitter shape used for spawning particles.
Align to Direction	Orients particles based on their initial direction of travel. This can be useful if you want to simulate, for example, chunks of car paint flying off a car’s bodywork during a collision. If the orientation isn’t satisfactory, you can override this property by applying a Start Rotation value in the Main module.
Randomize Direction	Blends particle directions towards a random direction. A value of 0 has no effect. A value of 1 completely randomizes the particle direction.
Spherize Direction	Blends particle directions towards a spherical direction, where they travel outwards from the center of their Transform. A value of 0 has no effect. A value of 1 points the particle direction outwards from the center, behaving identically to when the Shape is Sphere.
Randomize Position	Moves particles by a random amount, up to the specified value. A value of 0 has no effect. Any other value will apply some randomness to the spawning positions of the particles.

Edge

Property	Description
Radius	Defines the length of the edge.
Mode	Defines how Unity generates particles around the arc of the shape. For information on the Mode dropdown options, refer to Mode dropdown.
Spread	Controls the discrete intervals around the arc where particles can be generated. For example, a value of 0 means that particles can spawn anywhere around the arc, and a value of 0.1 means that particles can only spawn at 10% intervals around the shape.
Speed	Controls the speed the emission position moves around the arc. Set this value to Constant for the value to always remain the same, or Curve for the value to change over time. This property is available only when Mode is Loop or Ping-Pong.
Texture	Selects a texture to use for tinting and discarding particles. Important: You must enable the Read/Write property of the texture to use it in the Shape module component. Use the Game Objects view in Project Auditor (Window > Analysis > Project Auditor) to find and fix similar issues across your project.
Position	Applies an offset to the emitter shape used for spawning particles.
Rotation	Rotates the emitter shape used for spawning particles.
Scale	Changes the size of the emitter shape used for spawning particles.
Align to Direction	Orients particles based on their initial direction of travel. This can be useful if you want to simulate, for example, chunks of car paint flying off a car’s bodywork during a collision. If the orientation isn’t satisfactory, you can override this property by applying a Start Rotation value in the Main module.
Randomize Direction	Blends particle directions towards a random direction. A value of 0 has no effect. A value of 1 completely randomizes the particle direction.
Spherize Direction	Blends particle directions towards a spherical direction, where they travel outwards from the center of their Transform. A value of 0 has no effect. A value of 1 points the particle direction outwards from the center, behaving identically to when the Shape is Sphere.
Randomize Position	Moves particles by a random amount, up to the specified value. A value of 0 has no effect. Any other value will apply some randomness to the spawning positions of the particles.

Rectangle

Property	Description
Position	Applies an offset to the emitter shape used for spawning particles.
Rotation	Rotates the emitter shape used for spawning particles.
Scale	Changes the size of the emitter shape used for spawning particles.
Align to Direction	Orients particles based on their initial direction of travel. This can be useful if you want to simulate, for example, chunks of car paint flying off a car’s bodywork during a collision. If the orientation isn’t satisfactory, you can override this property by applying a Start Rotation value in the Main module.
Randomize Direction	Blends particle directions towards a random direction. A value of 0 has no effect. A value of 1 completely randomizes the particle direction.
Spherize Direction	Blends particle directions towards a spherical direction, where they travel outwards from the center of their Transform. A value of 0 has no effect. A value of 1 points the particle direction outwards from the center, behaving identically to when the Shape is Sphere.
Randomize Position	Moves particles by a random amount, up to the specified value. A value of 0 has no effect. Any other value will apply some randomness to the spawning positions of the particles.

Mode dropdown options

If Shape is Sphere, Hemisphere, Cone, Donut, Mesh, Mesh Renderer, Skinned Mesh Renderer, Circle, or Edge, the Mode property has the following options:

Value	Description
Random (default)	Generates particles randomly along the radius.
Loop	Generates particles sequentially along the radius of the shape, and loops back to the start at the end of each cycle.
Ping-Pong	Generates particles sequentially along the radius of the shape, and loops back to the start at the end of each cycle. Each consecutive loop happens in the opposite direction to the previous loop.
Burst Spread	Generates particles evenly along the radius. Use this mode for a more evenly distributed spread of particles compared to the default randomized behavior, where particles might clump together unevenly. Burst Spread is best used with burst emissions. This property is available only when Shape is Sphere, Hemisphere, Cone, Donut, Circle, or Edge.

Additional resources

Emission module reference

Velocity over Lifetime module reference