The trails can be launched in a spherical shape around the incoming points or along the burst’s direction (as set by Direction) when this is set to Line. Use Sphere if you want trails launching from the center of the explosion or Line when you want trails shooting out from the rising mushroom cloud.

The starting size of the burst in which trails will be launched. A value of 1 means the diameter of the burst is roughly 1 unit.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

The direction of the burst. You can change the direction to make the trails come out from the side of a building, for example.

When Shape is set to Sphere, this vector also corresponds to spread angle of 0. When using Line (Shape), the Direction controls the line that shoots out trails.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Controls the random scattering of starting points for trails. Change this value to obtain different trails for the same set of shape parameters.

The number of trails to generate per input point. Increase this parameter to create more trails.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

When Shape is set to Sphere, it sets the minimum angle the scattered points can spread out from the burst’s direction vector (as set by Direction). Set Guide Display to Distribution Guide to help visualize the given angle.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

When Shape is set to Sphere, it sets the angle trails can spread from Spread Start Angle towards the opposite of burst direction (as set by Direction). Set this to 180 degrees on a node with default settings to make the trails shoot out in all directions. Set Guide Display to Distribution Guide to help visualize the given angle.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

When Shape is set to Line, the trails are generated around a line representing the burst direction (as set by Direction). This parameter sets how far away this line should be created from its input point in world units.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

When Shape is set to Line, the trails are generated around a line representing the burst direction (as set by Direction). This parameter sets the length of the line in world units.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Azimuth controls how trails are generated around the burst direction (as set by Direction), therefore you can use it to generate trails only on a desired side of the explosion. By default, the value of 0 will create trails on the +X axis and they are rotated around the burst direction vector counter-clockwise as the value increases.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Azimuth controls how trails are generated around the burst direction (as set by Direction), therefore you can use it to generate trails only on a desired side of the explosion. Increasing this value will spread out the trails from the Azimuth Start Angle around the burst direction both clockwise and counter-clockwise. The value of 360 means that trails will be created all around the burst direction.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Removes some of the trails based on a noise pattern. Use this to create more interesting trail patterns. When this checkbox is turned on, Number of Trails might need to be increased to compensate for the removed trails.

Controls base feature size of the generated noise. The value applies to each axis.

The offset along the Y-axis. Change this value if the current noise pattern is undesirable.

The scale increment between iterations of fractal noise. The higher the value, the larger the “jaggedness” added to the output.

When Shape is set to Line, this controls the radius in which the points can be scattered along the length of the line. When the ramp’s value is 1, the radius is equal to Initial Size.

Sets the length (magnitude) of the launch velocity for the trails. Increase this to make the trails shoot out faster and cover larger distances during their life time.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Controls “verticality” of the paths for points further away from the center, when Shape is set to Line. The spread angle refers to the angle between the burst’s direction (as set by Direction) and a path’s starting velocity vector. Therefore, a spread angle of 0 will result in a path that’s aimed in the burst’s direction, and a spread angle of 90 will result in a path that starts out perpendicular to the burst’s direction. In the common case of Direction pointing away from Gravity, values near 90 will produce paths that are shooting out horizontally at the top of the emission line. Use the +/- button to quickly randomize the value per trail. The spread angle for the starting point of a path is fully determined by its distance to the burst center along the direction. When this distance is at Line Start or its sum with Line Length, spread angle will be set to Bottom Spread Angle and Top Spread Angle, respectively. The spread angle is linearly interpolated for distances between them.

Controls “verticality” of the paths for points closer to the center, when Shape is set to Line. The spread angle refers to the angle between the burst’s direction (as set by Direction) and a path’s starting velocity vector. Therefore, a spread angle of 0 will result in a path that’s aimed in the burst’s direction, and a spread angle of 90 will result in a path that starts out perpendicular to the burst’s direction. In the common case of Direction pointing away from Gravity, values near 90 will produce paths that are shooting out horizontally at the bottom of the emission line. Use the +/- button to quickly randomize the value per trail. The spread angle for the starting point of a path is fully determined by its distance to the burst center along the direction. When this distance is at Line Start or its sum with Line Length, spread angle will be set to Bottom Spread Angle and Top Spread Angle, respectively. The spread angle is linearly interpolated for distances between them.

When this checkbox is turned on, it changes the direction of the trails based on a noise pattern. Use this to randomize and create more variation in the trail directions.

Sets the strength of the noise. Higher values will create more variation between the trails.

Controls base feature size of the generated noise. The value applies to each axis.

The offset along the Y-axis. Change this value if the current noise pattern is undesirable.

The scale increment between iterations of fractal noise. The higher the value, the larger the “jaggedness” added to the output.

When this checkbox is turned on, it changes the length (magnitude) of the launch velocity for the trails based on a noise pattern. Increasing launch velocity makes the trails shoot out faster and cover more distance during their lifetime.

Sets how much of the launch velocity can be scaled down from its original length. The value of 1 means, that no velocities will be shorter than their original length.

Sets how much of the launch velocity can be scaled up from it’s original length. The value of 1 means, that no velocities will be longer than their original length.

Controls base feature size of the generated noise. The value applies to each axis.

The offset along the Y-axis. Change this value if the current noise pattern is undesirable.

The scale increment between iterations of fractal noise. The higher the value, the larger the “jaggedness” added to the output.

Limits the magnitude of the launch velocity. Use it to limit the minimum or the maximum launch speeds.

Limits the minimum launch speed.

Limits the maximum launch speed.

Sets the air resistance for the projectiles. Higher values will result in faster loss of energy and shorter travel distance. A Drag of zero will produce a symmetric arc.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Sets the mass for the projectile. Higher values will cause the projectile to more strongly resist drag and travel a longer distance.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Sets the force that attracts the projectile towards the ground. Set all components to zero if you want straight trails, which are not affected by gravity.

The number of divisions in the path for every second of time. Usually one wants a division per frame, thus this is often related to your frames per second.

Sets how many times to divide the trail into further segments. The larger the number, the more points will be created for each curve to help with post-deformations. You do not need to change this parameter from the default, if you do not intend to apply any post-deformation.

This node sets the startframe primitive attribute on the generated curves to indicate when each trail is to start. This parameter can be used to control timing of the projectiles. The startframe attribute gets set on the incoming points before the trails are seeded; therefore, all points created from the same input point will have the same start frame. Use Offset per Point to vary the start frame per scattered point. Use the button to the right of this parameter to visualize start frames for scattered points; grey points haven’t triggered at the current frame, while red ones have.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Sets the maximum allowed start frame offset for each trail. You need to turn this on to vary the start frames for trails generated from the same input point. This will set the offset value as unit of frames, when you only need couple of frames as offset. However, if you need an offset longer than a few seconds, using As Time Duration might be a better alternative. Random Distribution will pick startframe values between Start Frame and Start Frame + Offset per Point, which can be useful when Shape is set to Sphere. Use Along Direction when Shape is set to Line to start the trails gradually along the burst’s direction (as set by Direction).

When Shape is set to Line, this ramp allows you to start the trails that are closer to the burst center before ones that are further away. The left side of the ramp applies to trails that are the closest to the burst center, while the right side is for trails that are the furthest. When the ramp’s value is set to 0, it will set startframe to the value given by Start Frame. When the ramp’s value is 1, it will set startframe to Start Frame + Offset per Point.

Sets the length of the trails in frames. Higher values produce longer trails.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Sets how fast the projectile is moving on the trail path. Lowering this value will make the projectiles move slower, while increasing this value will make them move faster.

Click the randomization button on the right side of this parameter to randomize the value per incoming element. This will create/select a corresponding attribute adjust node to give you greater control over the parameter’s value.

Sets the maximum allowed variation for Speed Scale. The generated scales will be between Speed Scale and Speed Scale + Variation.

Controls the random selection for variation. Change this value if the current variation is undesirable.

Turning on this checkbox lets you clip projectiles that fall below Clip Height on the Y-axis.

The height to use for clipping. Trajectories will terminate once the Y coordinate falls below this value.

Turns on a basic collision detection system for the path to collide with objects.

The SOP path to the geometry the projectile paths need to collide with. If the geometry contains a kill primitive attribute that is set to 1, trajectories will terminate when they hit that primitive; otherwise, they will bounce and continue.

The maximum number of allowed bounces for projectile paths. After this number of bounces, the path will terminate. Set this to 0, if you want to eliminate all projectiles on the first collision hit.

Specifies what fraction of the original speed is maintained on collision in the direction of the collision normal. A value of 1 will simply reverse this normal component of velocity, whereas smaller values will also reduce it. A value of 0 will kill the projectile upon collision.

Specifies what fraction of the original speed is maintained in the tangential plane of the collision. A value of 1 will leave the tangential velocity unaffected; a value of 0 will eliminate the tangential component of velocity after the collision.

Copies custom created point attributes from the input points to the generated trails. This will ignore copying all internally used attributes.

Only copy attributes whose names match this pattern. The default * copies all attributes. This will ignore copying all internally used attributes.

When this checkbox is turned on, attributes will be promoted from input points to curve primitives that they generate.

The primitive attribute storing a unique id attribute for each generated path.

The primitive attribute storing the index number of the generated trails.

The primitive attribute storing length of the velocity vector at the start of each trail.

The primitive attribute storing the time when the trail ends.

When this checkbox is turned on, the trailid primitive attribute will be created to store the value used by the Randomization By parameter.