You can find all particle types in a scene by selecting the Particle Types filter in the explorer.
After you define the particle emitter object and the emission properties in the Emission property editor (see previous section), you can edit the characteristics of particles. The characteristics of these particles are collectively referred to as a particle type.
Particle types are like the recipes or templates that describe what each group of particles looks like. They define the particles’ physical characteristics such as their mass, size, and life span, as well as their color and interaction with natural forces and obstacles.
The particle points defined for a particle type belong to a cluster, which makes it easy to identify a particle’s owner. You can find the particle types in the Clusters list under the cloud’s node in the explorer. Because the particles associated to a particle type belong to a cluster, you can, for example, use a different shader on each particle type in a cloud (see Using the Particle Shaders) or deform the particles for each particle type using cluster-based deforms (see Creating Goals for Particles).
You can have an unlimited number of particle types and apply them to any emitter object in any scene, one at a time. As well, you can have multiple emitters using the same particle type. This lets you create a “library” of particle types presets (see Saving and Loading Particle Type Presets) that you can apply to any emitter in any particle system in any scene.
To create a new particle type
1. Do one of the following:
- Open the Emission property editor. To access this editor, select the particle cloud and choose Inspect > Emissions and select the appropriate emission property.
or
- If you have the ParticlesOp property editor open, click the Emission tab.
2. Select an existing particle type to use from the ParType list, or click the New button beside the ParType list to create the new particle type.
This automatically associates the new particle type to this emitter
3. Click the Edit button to modify or assign properties to the particle type, as described in the next section.
To create a new particle type with no emitter
• Choose Create > Particles > New Particle Type > Billboard, Blob, or Sphere.
This creates a new particle type with a specific shader attached to the particles to give them the appropriate surface (see The Basic Particle Render Type Shaders).
After you create a particle type this way, you must associate it to an emitter and particle cloud as described in Adding Multiple Particle Emitters to the Same Cloud.
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You can find all particle types in a scene by selecting the Particle Types filter in the explorer. |
The fundamental characteristics of each particle type are set in their property editors. The default particle type used in particle emission is called PType, and it appears at the top of the Emission property editor in the ParType list. You can modify the default particle type and save it under a new name.
1. In the Emission property editor, click the Edit button beside the ParType list to display the Particle Type property editor for the current particle type, or click the PType tab below the Emission property page.
2. The Overview page in the Particle Type (PType) property editor contains the most commonly used parameters for particle types. Setting parameters here is the same as setting them on their respective pages in this property editor.
Click the General tab and modify the particle type properties as summarized in the following illustration.
Animating and Varying the Particle Type Parameters
Many of the particle type parameters have animation controls that let you vary the way in which their values are animated. Once you set keys for their values, you can choose to have the animation “defined” in a number of ways such as from Birth, Age, and Absolute (for Color and Size, you can also use Age %).
For example, to animate the particle speed, select Age for the Allowed Linear Velocity Range - Max parameter to slow down a particle over its lifetime, or use Abs(olute) to slow down all particles at the same time. See Animating Particle Type Parameters for information on all of these.
Many of the particle type parameters also have Var (variation) and Seed parameters which let you add variation to the parameter’s value. For information on this, see Adding Variation to Particles.
Other Pages in the Particle Type Property Editor
For information on the other pages of the Particle Type property editor:
• Events—see Creating a Particle Event. This is available only for the Particles simulator, but you can create collision events with obstacles with any of the particle-based simulators by using the standard method of setting obstacles (see Setting Up Obstacles).
• Envir(onment)—see Setting Up Forces for Each Particle Type.
• Noise—see Adding Noise to Particles. This is available only for the Particles simulator.
• Interpart(icle Collisions)—see Making Particles Collide with or Avoid Each Other. This is available only for the Particles simulator.
• Fluid—see Defining the Fluid Particle Type. This is available only for the Fluid simulator.
• Explosion—see Setting Up the Structures. This is available only for the Explosion simulator.
• Color—see Setting a Particle’s Color.
• Sprite—see Rendering Sprites. This is available only for the Particles simulator.
• Instancing—see Creating Instances of Objects to Attach to Particles. This is available only for the Particles and Fluid simulators.
Setting the Particle’s Lifetime
You alone have the power to decide how long a particle lives by using the options in the Life section of the Particle Type > General page:
• Max Life controls the maximum length of time (in seconds) that the particle exists once it is emitted.
• Live Forever makes the particles live for such a long time that it seems like forever (69,999 frames, to be exact). This option is useful for effects such as creating static clouds in conjunction with an initial state (see Creating an Initial State for Particles). As well, you may want to select this option to have the particles always available as you’re tweaking their parameters.
However, if you need an effect to work based on the Max Life value that determines the particles’ life span (particles animated with Age%), selecting the Live Forever option eliminates that possibility. This includes using the Particle Gradient shader.
Setting the Particle’s Mass and Size
Size controls the size of the particle when it is born, in Softimage units. The farther away a particle appears in the viewing area, the smaller it appears when it is rendered. To have a particle change size over its lifetime, you can use the animation controls beside this parameter. For an example, see Creating a Size Shift with Age %.
Mass specifies the mass of particles, which determines how swiftly they react to the forces applied to them (except gravity) and how they react in a collision with an obstacle. The more massive a particle, the more difficult it is to change its motion. Therefore, to make a change in a particle’s motion, you need to apply stronger forces to a particle with more mass than to particle with less mass.
Gravity, however, is a little different from the other forces. Gravity is a force directly proportional to the particle mass. The more massive the particle, the stronger the gravity force applied to it. As a result, several particles of different masses will all have the same motion if the only force acting upon them is gravity.
Saving and Loading Particle Type Presets
Each time you edit properties in a property editor, you can save your settings as a preset. Presets are simply data files with a .preset file extension that contain property information. Animation information, however, is not saved as part of the preset.
Presets let you work more efficiently because you can save the modified properties and reuse them as needed. As well, presets lets you transport information between scenes. With particle types, all the particle type information set in its property editor is saved, as well as its render tree (see Connecting Shaders in a Particle Render Tree).
To save a preset
1. Open the Particle Type property editor and click the Preset icon and choose Save Preset from the menu.
You can also save presets with the Particle Type page inside the Emission and ParticlesOp property editors. Just make sure that the Particle Type page is active (click its tab at the top of the current property editor).
2. In the Save Preset browser, select the folder in which you wish to save the preset. It is recommended that you do not save your presets in the DSPresets folder.
3. In the File Name text box, enter the name you wish to give the preset, then click OK.
To load a preset
1. Open a Particle Type property editor and click the Preset icon and choose Load Preset from the menu.
2. Make sure that you have the correct property editor open for the preset that you saved.
3. In the Load Preset browser, select the preset you wish to load and click OK.
The selected preset parameter values appears, replacing those of the currently displayed property set.
After you’ve worked with particles for awhile, you may have a number of particle types defined that you no longer want to keep. To delete them, you need to use the explorer.
However, before you delete them, make sure that they’re not currently in use in a scene: if they are, you won’t be able to delete them.
To delete a particle type
1. In the explorer, select the Scene > Particle Types scope.
2. From the ParTypes > List, select the particle types you want to delete.
3. Do one of the following:
- Press Delete.
- Right-click the particle type and choose Delete.
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