Shape module
This module defines the shape (the volume or surface) from which particles can be emitted, and the direction of the start velocity. The options available vary depending on the Shape you choose - Cone and Mesh have slightly different menu options.
Properties
| Property | Function |
|---|---|
| Shape | The shape of the emission volume. |
| Sphere | Uniform emission in all directions. |
| Hemisphere | Uniform emission in all directions on one side of a plane. |
| Cone | Emission from the base or body of a cone. The particles diverge in proportion to their distance from the cone’s centre line. |
| Box | Emission from the body of a box shape. The particles move in the emitter object’s forward (Z) direction. |
| Mesh | Emission from any arbitrary Mesh shape supplied via the Inspector. Mesh contains an extra menu to select whether particles are emitted from the vertices, triangles or edges of the Mesh. |
| MeshRenderer | Emission from a reference to a GameObject’s Mesh Renderer. |
| SkinnedMeshRenderer | Emission from a reference to a GameObject’s Skinned Mesh Renderer. |
| Circle | Uniform emission from the centre of edge of a circle. The particles move only in the plane of the circle. |
| Edge | Emission from a line segment. The particles move in the emitter object’s upward (Y) direction. |
|
Angle (Cone only) |
The angle of the cone at its point. An angle of 0 produces a cylinder while an angle of 90 gives a flat disc. |
|
Radius (Sphere, Hemisphere, Cone, Circle and Edge only) |
The radius of the circular aspect of the shape. |
|
Length (Cone only, when using one of the volume Emit from modes) |
The length of the cone. |
|
Box X, Y, Z (Box only) |
Width, height and depth of the box shape. |
|
Mesh (Mesh, MeshRenderer and SkinnedMeshRenderer only) |
The Mesh that provides the emitter’s shape. |
|
Emit from Shell (Sphere and Hemisphere only) |
Enable this to make particles be emitted from the outer surface rather than the inner volume of the shape. |
|
Emit from (Cone only) |
Selects the part of the cone to emit from: Base, Volume, Base Shell or Volume Shell. |
|
Arc (Circle only) |
The angular portion of a full circle that forms the emitter’s shape. |
|
Emit From Edge (Circle only) |
Enable this to make particles be emitted from the edge of the circle rather than the centre. |
| Single Material | Should the particles be emitted from a particular sub-Mesh (identified by the material index number). If enabled, a numeric field is shown allowing you to specify the material index number. |
| Use Mesh Colors | Use, or disregard, Mesh colors. |
| Normal Offset | Distance away from the surface of the Mesh to emit particles (in the direction of the surface normal) |
| Align to Direction | This will cause particles to be rotated based on their initial direction of travel. To apply a custom rotation direction on top of this setting, configure the Start Rotation setting in the Main module. |
| Random Direction | When enabled, the particles’ initial direction will be chosen randomly. |
Details
All the shapes except Mesh have properties that define their dimensions (such as Radius). These can be edited by dragging the handles on the wireframe emitter shape in the Scene view. The choice of shape affects the region from which particles can be launched but also the initial direction of the particles. For example, a Sphere emits particles outward in all directions, a Cone emits a diverging stream of particles, and a Mesh emits particles in directions that are normal to the surface.
Align to Direction
Use this checkbox to orient 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 is not satisfactory, you can also override it by applying a Start Rotation value in the Main module.
Mesh shape source
Skinned Meshes can be used as a source for a particle emitter. Additionally, MeshRenderer types are supported. Simply assign the Mesh instance in the Shape module to have particles emit from the surface of an instantiated Mesh.
It is possible to choose to emit only from a particular material (sub-Mesh), and to offset the emission position along the Mesh’s normals. This option allows users to offset particles from the surface of a Mesh.
It is also possible to ignore the color of the Mesh.