Aux System group

The Aux System is a particle system within the main particle system, thus the name Aux or 'Auxiliary' System. Aux particles are emitted from the main particles system either continuously or when the main particles collide. Aux System is useful for creating effects like particle trails, particle traces and organic lines.

Read about more Aux controls and our 'Emitting Particles from Particles' tutorial on the Aux Subgroups page.

Emit pop-up

Emit turns on the Aux particle system. By default, this option is set to Off.

Choose either of the other options to activate the Aux System. At Bounce Event tells the Aux particles to be emitted at a collision event. At Bounce Event tells the Aux particles to be emitted continuously.

Aux Off | Aux On> Continuously

Emit Probability [%] (Options panel in v1.5)

Emit Probability sets how many of the main particles actually produce Aux particles. Probability is measured in percentage. Low values produce fewer particles. Higher values produce more particles.

Left to right, Emit Probability is low and high.

Particles/sec, Particles/collision

The Emit popup sets the rate of Aux particle emission. Particles are measured in seconds when Continuously is chosen. Particles are measured by collision when At Bounce Event is chosen. Low values create a low emission of Aux particles. Higher values create more emission and more Aux particles.

Left to right, Particles/sec is low and high. Emit set to Continuously.

Life

Life controls the lifespan of the Aux particles, or how long they live onscreen. Low values give the particles a shorter lifespan. High values give the particles a longer lifespan. Has a related Life Randomness parameter in the Aux System> Randomness group.

Velocity

Sets the initial velocity of the Aux particles at birth. Low values make the particles start slower. High values make the particles start faster. This parameter is sometimes referred to as 'Initial Velocity' in Trapcode Particular documentation.

Type pop-up

Type choose the Particle Type used by the Aux System. These are the same choices as the main particles, except that custom particles are not available, which excludes using Sprites or Textured Polygons. See the Particle Types page for an explanation of particles.

The Same as Main option is active by default. This tells the Aux System to use the same Particle Type that the main particle system is using. This option is often helpful in keeping a consistent look to your composition. The main particle type is set in the Particle group> Particle Type popup.

Technical Note: There is a limitation on Aux particles. Aux particles do NOT behave as full Textured Polygons if the main Particle Type is set to Layer> Textured Polygon. The Aux particles do take on the the polygon characteristic of orbiting around the composition camera. However, their rotation is limited since there is only a Rotate Speed control for the Z axis. We intend to improve this Aux functionality in later versions of Trapcode Particular.

At left, main particle is Textured Polygon, Aux particle is Same as Main. In middle, main particle is Textured Polygon, Aux particle is Star. At right, main particle is Star, Aux particle is Same as Main.

Size, Size over Life

Size sets the size of Aux particles. High values create a larger particle. Has a related Size Randomness parameter in the Aux System> Randomness group.

Size over Life controls how this Size varies over the particles' lifespan. Read more on the Over Life page.

Opacity, Opacity over Life

Opacity sets the opacity level of Aux particles. High values give a higher opacity. Low values give more transparency. Has a related Opacity Randomness parameter in the Aux System> Randomness group.

Opacity over Life controls how this Opacity varies over the particles' lifespan. Read more on the Over Life page.

Color, Color over Life

Color sets the coloration of Aux particles.

Color over Life controls how this Color varies over the particles' lifespan. Read more on the Over Life page.

Color From Main [%]

Enables Aux particles to inherit the color from the main particle that created them. Measured in percentage. High values inherit a lot of main particle color. Low values take on less main particle color.

The main particle color is set by the Particle group's Color and Set Color controls.

Left to right, Color From Main set low and high. In the Particle group, Color is red and Set Color is At Birth.

Gravity

Gravity makes the Aux particles fall downwards in a natural way. The particles pick up speed as they fall, just like any object in real world would. Low values make the Aux particles fall slowly. High values make the Aux particles fall more quickly.

Transfer Mode pop-up

The Transfer Mode controls how Aux particles are composited together. There are three options: Normal, Add and Screen. See a similar example on the Glow group page.

- Normal. The normal composite operation.
- Add. Particles are added together. Useful for light effects and fires.
- Screen. Particles are screened together. Useful for light effects and fires.

Rotate Speed

Controls how fast the Aux particles rotate. High values make the particles rotate quickly. Low values make the particles rotate slowly.

Unlike the Rotation group for main particles, this single Rotation value controls rotation only around the Z axis. When keyframing this parameter, all Aux particles born at a certain frame will get the current Rotation Speed.

Feather

Sets the softness of the Aux particles. High values give a feathery soft edge to the particle. Lower values give a more globular, solid edge. See a similar example on the Glow group page.

Control from Main Particles group

These three controls let you modify how and when the Aux particles are emitted by the Aux System. Read more on the Aux Subgroups page.

Physics (Air mode only) group

These three controls give the Aux particles separate settings for three corresponding controls in the Physics> Air group. Read more on the Aux Subgroups page.

Randomness group

These three controls apply a Randomness value to three corresponding controls in the main Aux System group. Read more on the Aux Subgroups page.