3D Compositing with Action > Action: The Particle System > Customizing the Particle Stream >
Using Custom Particles

You can create particle streams using your own 3D objects or text. You can also use the shape of any surface for each particle. For example, create custom particles using a light source, 3D object, or surface as a particle generator. See Generating Particles.

To use a 3D object or text as a custom particle:

1. From the node bin, add a particle generator to your scene.
2. In the schematic, double-click the Particle Generator node to access the Generator menu.

   (a) Interactive Type box(b) Render Type box

3. From the Render Type box, select Node as the particle type and change the Interactive Type box to Node to view the 3D object or text as you make changes to your particle stream.
4. Import the 3D object or create the text. See Importing 3D Models or Changing 3D Text Properties.
   TipThe 3D object or text used for the custom particle can also include a deformation mesh. See Deforming Models and Surfaces.
5. In Schematic view, rename your 3D object or text “ParticleDraw”. This name is case sensitive so make sure it is typed exactly as shown.
6. Parent the particle generator to the 3D object or text.

   If you want to add transformations, such as rotating all the particles, parent the particle generator to the axis of the 3D object or text as shown in the next step.

7. Hide the 3D object or text.

   The particle generator uses the 3D object or text named ParticleDraw. The following figure shows the schematic and the result of using the letter A as a custom particle and a light source as the particle generator.

To use a surface as a custom particle:

1. Add a particle generator.

   You can use a light source, 3D object, or surface as a particle generator. See Generating Particles.

2. Select Node as the particle type in the Render Type box. To view the surface as you make changes to your particle stream, change the Interactive Type box to Node as well. See Setting Particle Rendering Properties.
3. Add a surface to the scene. It can be an image, a bilinear, a bicubic, or an extended bicubic surface. See Adding Surfaces.
   NoteYou do not have to apply media to the surface because the particle generator only uses the surface's shape and not its media. To have an image appear on each particle, you have to apply a texture to the particle generator. See Applying Textures to Particles.
4. Rename your surface “ParticleDraw”. This name is case sensitive so make sure it is typed exactly as shown.
5. Parent the particle generator to the surface.

   If you want to add transformations, such as rotating all the particles, parent the particle generator to the axis of the surface as shown in the next step.

6. Hide the surface.

   The following figure shows the schematic and the result of using a bicubic surface as a custom particle and a light source as the particle generator. The shape of the bicubic surface is animated and its axis is used to rotate the particles.

NoteYou can animate the shape of a bilinear, bicubic, or extended bicubic surface, and have the particles reflect the animation.