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| Since | 18.5 |
Overview ¶
This node takes the incoming static points and replicates clusters of points around them in some arbitrary “blob” shapes that capture an explosion’s initial form when Burst Type is set to Explosion or Muzzle Flash.
Points are scattered onto the surface of a “blob” shape when the burst shape is generated.
When Burst Type is set to Shockwave, the points are generated onto a three dimensional sphere, and can be limited to a specific slice on this sphere, giving you a flat shockwave ring spreading on ground or a three dimensional dome blast shape.
When Burst Type is set to Blast Rings, the points are generated onto multiple flat two dimensional rings that are aligned inside a three dimensional dome. This can be used to create rings spreading above the fireball as the dome blast shape expands. This type of behavior can be observed mostly on very large scale, such as nuclear explosions.
These leading points are then trailed towards the center of the explosion to give a desirably dense point distribution inside the burst shape. Finally, each point is animated outwards from the center of the burst to give a sense of expansion.
Note
It is important that the number of incoming points stay constant over time.
Warning
When working on explosions from a fast moving object, it is possible to animate the position (P) of the incoming points, however other attributes controlling burst properties should never be animated over time.
Burst components ¶
A burst is made of replicated clusters of points or what we call burst components. Each burst component represents a source attribute for pyro simulations. For each component, one of the following source attributes can be selected, which creates the corresponding point attribute.
-
Density (
density), represented as grey color. -
Temperature (
temperature), represented as blue color. -
Divergence (
divergence), represented as orange color. -
Burn (
burn), represented as yellow color. -
Color (
Cd), which you determine. -
Alpha (
Alpha), represented by purple color.
The output of this node will be a mix of burst components, each responsible for sourcing its own specified attribute. These attributes should be rasterized into volumes using the 
Volume Rasterize Attributes SOP, at which point they can be sourced into a pyro simulation. The Source Attribute (source_name by default) is created on points to ensure that each component only contributes to rasterization of its own attribute. For example, the temperature attribute will be set to 0 for points from the burn component, so using these burn points during temperature rasterization would lower the values in the final source volume.
The velocity (v) attribute is a special exception. By default, v is appended to the Source Attribute of each point, signaling that all points should be used when rasterizing the velocity field. You can use Cull Velocity in the Quick Setups menu if you prefer to have only one burst component contribute to velocity rasterization.
Note
Prefix Attribute Name provides a way to prefix the source attribute’s name with burst_. This is useful for differentiating between sources created by this node and the 
Pyro Trail Source SOP.
Tip
Run the Source Volume option from the Quick Setups menu to quickly create a Volume Rasterize Attributes node that is automatically appended and updated based on the parameters on this node.
Customizing bursts ¶
You can also generate multiple bursts with one node. By default, all bursts will have the same properties, as set by the node’s parameters (such as Initial Size, Direction, etc.). To vary these properties for each burst, select the Set Varying option on the menu next to the corresponding parameter. This will use a different random value in the provided range for each input point. These generated random numbers are seeded with point number by default; to use a custom integer attribute instead, set Randomization By to Seed Attribute. This will ensure that randomized properties will remain the same for an input point even if points are shuffled or removed from the input, provided the value of the Seed Attribute stays the same.
You can also manually override parameter values with attributes. For example, if the input geometry has a pscale point attribute, its values can be used instead of the global Initial Size. This allows you to finely control the size of each burst. To this end, the menu next to the corresponding parameter must also be set to Use Attribute.
Parameters that can be controlled by point attributes are listed in the table below.
Parameter Name |
Range |
Attribute Name |
Attribute Type |
|---|---|---|---|
Initial Size |
0 to ∞ |
|
float |
Direction |
(-1,-1,-1) to (1,1,1) |
|
vector |
Rings per Burst |
0 to ∞ |
|
integer |
Spread Start Angle |
0 to 180 |
|
float |
Spread Angle |
0 to 180 |
|
float |
Azimuth Start Angle |
0 to 360 |
|
float |
Azimuth Angle |
0 to 360 |
|
float |
Distribution Length |
0 to ∞ |
|
float |
Roundness |
0 to 1 |
|
float |
Muzzle Length |
0 to ∞ |
|
float |
Number of Trailings |
0 to ∞ |
|
integer |
Trailing Separation |
0.001 to ∞ |
|
float |
Trailing Depth |
0 to 1 |
|
float |
Start Frame |
∞ to ∞ |
|
float |
Frame Duration |
1 to ∞ |
|
integer |
Outward Expansion |
0 to ∞ |
|
float |
Interior Expansion |
0 to ∞ |
|
float |
Exterior Expansion |
0 to ∞ |
|
float |
Directional Expansion |
0 to ∞ |
|
float |
Directional Translation |
0 to ∞ |
|
float |
Points with attributes corresponding to the name of the burst components will act as a multiplier on that source value. This provides fine control over each burst’s source values. A source attribute with a value of 0 will not create the corresponding burst component. For example, you can set the density attribute to 0 on some selected points, and those bursts will not generate a density component.
Burst Component |
Attribute Name |
Attribute Type |
|---|---|---|
Density |
|
float |
Temperature |
|
float |
Divergence |
|
float |
Burn |
|
float |
Color |
|
vector |
Alpha |
|
float |
Explosion types ¶
-
Single explosion:
-
Single burst method uses a single input point to generate a burst. This can be used for a single fireball or a smaller explosion.
-
Multi burst method uses multiple input points to generate multiple bursts for a single explosion (3-4 points are recommended). The input points should be scattered in a relatively close distance to each other, and their
startframevalues should also differ by a couple of frames to prevent all of the bursts from triggering simultaneously.Compared to single burst, this method can create more interesting explosion shapes.
-
-
Consecutive explosions:
-
Consecutive multi burst method uses multiple clusters of points to represent each explosion. Each cluster should contain 3-4 points, same as the multi burst method. The
startframeattribute values for points inside a cluster should be very close to each other with only a couple of frame difference, while the averagestartframevalue for each cluster can vary to time the explosions. In this case, you may want to run each explosion as a separate pyro simulation.
-
Parameters ¶
Group
The subset of the input points to use for burst generation. Leave this blank to use all points.
Guide Display
Set this menu to Proxy Shape to visualize the hull of the generated burst shape. The proxy shape remains visible even after the its burst has ended.
Quick Setups
This menu lets you run some simple scripted setups to help with the most common tasks.
Single Input Point
Creates an 
Add node with a single point that is ready to be positioned where you need the explosion to happen.
Color by Start Frame
Creates an 
Attribute Wrangle node upstream that helps you visualize the startframe point attribute over time to see when each input point is triggered.
Cull Velocity
Creates an Attribute Wrangle node downstream that modifies the Source Attribute to ensure that a single burst component will contribute to velocity rasterization.
Source Volume
Creates a Volume Rasterize Attributes node that is linked and automatically updated based on the parameters on this node.
Pyro Simulation
Creates a simple setup to quickly simulate a simple explosion.
Initialize
Force Uniform will set all parameter override menus to Set Uniform; use this if you want all burst properties to be controlled by the parameter interface. Use Attribute will look for incoming attributes and corresponding parameters will be set to Use Attribute.
Additional Guides
Turn on this checkbox to see trails as guides while displaying this node. This can help synchronize the animation of different elements. It can accept a white-space separated list of 
Pyro Trail Path nodes.
Randomization By
Controls how the random selection is seeded for parameters that are using Set Varying. Topology changes on the input geometry can shift element numbers, causing a different random selection to be used. Seed Attribute lets you provide an integer attribute to make sure the random value is not dependent on element order.
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.
Seed Attribute
The integer type attribute to use for random selection for parameters that are using Set Varying.
Burst Shape ¶
Burst Type
Sets the specific burst shape this node will generate.
Explosion
Generates a generic 'blob' shape suitable for explosions.
Muzzle Flash
Generates an 'elongated blob' shape along a direction (specified by Direction), making it suitable for a flash coming out of a firearm, or a powerful ground explosions bursting towards the sky.
Shockwave
Generates an arbitrary slice on a three dimensional sphere, making it suitable for a flat ground shockwave or three dimensional blast in a dome shape.
Blast Rings
Generates a set of flat rings that align with a dome blast as it expands through the air. This type of behavior can be observed mostly on a very large scale, such as a nuclear explosion.
Shape Offset
Controls random selection for the burst shape. Change this value to obtain different burst shapes.
Initial Size
The starting size of the burst. 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.
Initial Size Scale
Scales the existing pscale attribute by this amount when the menu is set to Scale Attribute. This allows you to quickly scale your burst without needing to adjust the attribute value.
Variation
Sets the maximum allowed variation. Sizes will be between Initial Size - Variation and Initial Size + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Direction
The direction of the burst. For example, you can change the direction to make the burst come out from the side of a building. This vector also controls how Directional Expansion is applied.
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.
Variation
Sets the maximum allowed variation in degrees. The varied direction will spread out in a cone shape from Direction.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Rings per Burst
The number of rings to generate per input point, when Burst Type is set to Blast Rings. Increase this parameter to create more rings. The rings are distributed inside the already expanded blast dome. Therefore, some of the rings are only generated as the blast expands over 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.
Variation
Sets the maximum allowed variation in degrees. Start angles will be between Spread Angle Start - Variation and Spread Angle Start + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Distribution Length
When Shape is set to Blast Rings, the rings are generated on a line representing the burst direction (as set by Direction). This parameter sets the length of the line in world units. It also influences when each ring gets generated inside the expanding blast dome.
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.
Variation
Sets the maximum allowed variation for Line Length. The generated values will be between Line Length - Variation to Line Length + Variation.
Change Distribution Along Height
Turning on this parameter lets you control the distribution of the rings along the distribution length (as set by Distribution Length) using a ramp parameter, when Shape is set to Blast Rings.
Distribution Ramp
Lets you control the distribution along the distribution length (as set by Distribution Length), when Shape is set to Blast Rings. The horizontal axis represents the distribution length, while the vertical axis represents the probability of generating a point in that region. Where the ramp is set to 0, no rings will be generated at its corresponding length.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Spread Start Angle
Sets the minimum angle the scattered points can spread out from the burst’s direction vector (as set by Direction), when Burst Type is set to Shockwave.
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.
Variation
Sets the maximum allowed variation in degrees. Start angles will be between Spread Angle Start - Variation and Spread Angle Start + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Spread 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.
Variation
Sets the maximum allowed variation in degrees. Spread angles will be between Spread Angle - Variation and Spread Angle + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Azimuth Start Angle
Controls how points are scattered around the burst direction (as set by Direction), when Burst Type is set to Shockwave or Blast Rings. Therefore, you can use it to generate points on only one side of the burst. By default, the value of 0 will create points on the +X axis and they rotate 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.
Variation
Sets the maximum allowed variation in degrees. The generated values will be between Azimuth Start Angle - Variation to Azimuth Start Angle + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Azimuth Angle
Controls how points are scattered around the burst direction (as set by Direction), when Burst Type is set to Shockwave or Blast Rings. Therefore, you can use it to generate points on only one side of the burst. Increasing this value will spread out the points from the Azimuth Start Angle around the burst direction both clock wise and counter-clockwise. A value of 360 will create points 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.
Variation
Sets the maximum allowed variation in degrees. The generated values will be between Azimuth Angle - Variation and Azimuth Angle + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Roundness
Controls the symmetry of the generated shape. A value of 1 will use the same length for all seeded spikes, while lower values will add more irregular-sized spikes.
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.
Variation
Sets the maximum allowed variation. The generated values will fall between Roundness - Variation and Roundness + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Muzzle Length
Controls the length of the muzzle shape along it’s direction (set by Direction), when Burst Type is set to Muzzle Flash.
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.
Variation
Sets the maximum allowed variation. The generated values will fall between Roundness - Variation and Roundness + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Add Shape Noise
Adds noise to the shape, creating a more interesting shape for the blast, when Burst Type is set to Shockwave or Blast Rings.
Amplitude
Controls the strength of the noise. The stronger the value, the more the shape will differ from it’s original shape.
Size
Controls the base feature size of the generated noise. This value applies to each axis.
Offset
The offset along the Y-axis. Change the value of the Offset if the current noise pattern is undesirable.
Roughness
The scale increment between iterations of fractal noise. The higher the value the larger the “jaggedness” added to the output.
Number of Trailings
Controls the number of seeded spikes when generating the shape.
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.
Variation
Sets the maximum allowed variation in spike counts. The generated values will be between Number of Trailings - Variation and Number of Trailings + Variation.
Seed
Controls random selection for the burst shape. Change this value to obtain different burst shapes.
Trailing Separation
Sets the point density for source points. Smaller values will create denser point clouds for the burst, which will also yield more details in the rasterized source volumes. Larger values are suitable for background explosions.
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.
Variation
Sets the maximum allowed variation for trailing separation. The generated values will fall between Trailing Separation - Variation and Trailing Separation + Variation.
Seed
Controls random selection for the burst shape. Change this value to obtain different burst shapes.
Trailing Length
Sets the length of the trailings, measured in world units. The trailing will end at the center of the burst even if the value is set to a much longer length. Shorten the length if you want the source attribute present only on the outer shell of the burst. Use the +/- button to quickly randomize the value per point.
Variation
Sets the maximum allowed variation. Trailing lengths will be between Trailing Length - Variation and Trailing Length + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Trailing Thickness
Sets the width of the trails at the inner end of the trailing. Larger values will thicken the spikes at the base, but the burst shape will get destroyed if Trailing Thickness is set too large. Use the +/- button to quickly randomize the value per point.
Variation
Sets the maximum allowed variation for trailing thickness. The generated values will be between Trailing Thickness - Variation and Trailing Thickness + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Point Separation
Sets the point density for source points, when Burst Type is set to Shockwave or Blast Rings. Smaller values will create denser point clouds for the burst, which will also yield more details in the rasterized source volumes. Larger values are suitable for background bursts.
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.
Variation
Sets the maximum allowed variation for trailing separation. The generated values will fall between Trailing Separation - Variation and Trailing Separation + Variation.
Seed
Controls random selection for the burst shape. Change this value to obtain different burst shapes.
Trailing Depth
Sets the width of the trailing towards the inside of the shape, when Burst Type is set to Shockwave or Blast Rings. Smaller values will create denser point clouds for the burst, which will also yield more details in the rasterized source volumes. Larger values are suitable for background bursts.
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.
Variation
Sets the maximum allowed variation for trailing separation. The generated values will fall between Trailing Separation - Variation and Trailing Separation + Variation.
Seed
Controls random selection for the burst shape. Change this value to obtain different burst shapes.
Burst Animation ¶
Provides controls to procedurally animate the initial burst shape to get the sense of expansion. Some of the properties can be overwritten per burst component on the Burst Component tab.
Start Frame
Sets the frame on which the bursts triggers.
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.
Offset
Offsets the existing startframe attribute by this amount when the menu is set to Shift Forward or Shift Backward. This allows you to quickly shift the trigger frame without needing to adjust the attribute value.
Variation
Sets the maximum allowed variation in frames. Start frames will be between Start Frame and Start Frame + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Frame Duration
Sets the length of the expansion animation in frames.
Note
The corresponding attribute (life) must be expressed in seconds, whereas this parameter sets the duration in frames. You can set the life attribute in frames using an 
Attribute Adjust Float node by setting Unit Settings to Duration.
Tip
Scale Over Duration under Burst Components allows you to control the magnitude of source values over the duration of expansion. This is useful if you want to continue sourcing velocity after the primary source (such as density or temperature) itself is finished. To do so, you can increase Frame Duration and turn on Scale Over Duration. The default Duration Ramp will ensure that the source attribute is ramped down for the last leg of expansion, while the velocity attribute maintains its correct value.
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.
Variation
Sets the maximum allowed variation in frames. Durations will be between Frame Duration and Frame Duration + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Outward Expansion
Controls the fully expanded size of the burst in all directions. The value acts as a multiplier on top of Initial Size.
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.
Variation
Sets the maximum allowed variation. The generated values will be between Outward Expansion and Outward Expansion + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Expansion Over Duration Ramp
Controls how the burst inflates over the duration of its expansion. The horizontal axis of this ramp represents time, and the vertical axis is the amount of expansion. With the default ramp, the bursts will expand more quickly at the beginning of their lives.
Interior Expansion
Controls the fully expanded size of the interior ring of the shockwave in all directions. The value acts as a multiplier on top of Initial Size.
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.
Variation
Sets the maximum allowed variation. The generated values will be between Outward Expansion and Outward Expansion + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Interior Expansion Over Duration Ramp
Controls how the interior ring of the shockwave inflates over the duration of its expansion. The horizontal axis of this ramp represents time, and the vertical axis is the amount of expansion. With the default ramp, the shockwave will expand more quickly at the beginning of their lives.
Exterior Expansion
Controls the fully expanded size of the exterior ring of the shockwave in all directions. The value acts as a multiplier on top of Initial Size.
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.
Variation
Sets the maximum allowed variation. The generated values will be between Outward Expansion and Outward Expansion + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Exterior Expansion Over Duration Ramp
Controls how the exterior ring of the shockwave inflates over the duration of its expansion. The horizontal axis of this ramp represents time, and the vertical axis is the amount of expansion. With the default ramp, the shockwave will expand more quickly at the beginning of its life.
Directional Expansion
Sets the fully expanded size of the burst in its Direction. This value acts as a multiplier on top of Initial Size and Outward Expansion.
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.
Variation
Sets the maximum allowed variation. The generated values will fall between Directional Expansion and Directional Expansion + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Directional Translation
Sets translation on the burst in its 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.
Variation
Sets the maximum allowed variation. The generated values will fall between Directional Expansion and Directional Expansion + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Burst Components ¶
Default Value
A global scale on all source attribute values, except color sources (Cd).
Scale Over Duration
Provides a ramp to control the source attribute values over the duration of the burst expansion. This will not apply to color sources (Cd). Turn this on if you want the burst to reduce emission as it reaches its end of life.
Duration Ramp
Controls how the source values change over the lifetime of the burst. The left side is the start of the burst, while the right side of the ramp represents the end of the burst. This will not apply to color sources (Cd).
Scale Along Trailing
Provides a ramp to control the source attribute values over the trailings of the burst. This will not apply to color sources (Cd). Turn this on if you want the burst to emit larger source values near the center of the burst.
Trailing Ramp
Controls how the source values change across the trailings. The left side is the inside of the burst, while the right side of the ramp represents the outer tip of the trailings.
Number of Sources
Sets the number of source components that are created for each burst.
Create Source
The corresponding burst component will only be created when Create Source is turned on. Turn this off to quickly disable a component.
Attribute
Sets the source attribute for this burst component. Burst points that have a value of 0 for this attribute will not generate a burst component.
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.
Prefix Attribute Name
This will prefix the source attribute with the burst_. This is useful for differentiating between sources creating with this operator and those generated by the Pyro Trail Source SOP.
Source Value Scale
Scales the value of the source attribute for this burst component. Use the +/- button to quickly randomize the value per incoming point.
Variation
Sets the maximum allowed variation. The generated values will be between Source Value Scale - Variation and Source Value Scale + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Enable Noise
Changes the source value for the generated source points by a noise pattern.
Noise Operation
Sets how the noise pattern is combined with the source value. When this is set to Add, the generated noise values will be between negative Amplitude and positive Amplitude, and will be added to the source value. The values are between 0 and Amplitude when this is set to Multiply, and the final source value is obtained by multiplying it with noise.
Amplitude
Sets the strength of the noise.
Size
Controls base feature size of the generated noise. The value applies to each axis.
Offset
The offset into the noise field. Change the value of the Offset if the current noise pattern is undesirable.
Roughness
The scale increment between iterations of fractal noise. Higher values of Roughness produce finer details in the noise, while lower values yield a smoother noise field.
Base Color
Sets a constant color value for generated source points. The Base Color can be varied per trailing by enabling Hue Shift, Saturation, or Value.
Color
Sets the base color value for the source points. Hue Shift will be with respect to this color.
Hue Shift
When this checkbox is turned on, the hue is varied per trailing. Shifting by 0 produces the chosen Color, and other values correspond to moving along the color wheel.
Hue Shift Min
The minimum amount of hue shift. Each trailing will be given a hue shift between this minimum and Hue Shift Max.
Hue Shift Max
The maximum amount of hue shift. Each trailing will be given a hue shift between Hue Shift Min and this maximum.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Saturation
When this checkbox is turned on, color saturation is varied per trailing. Higher saturation corresponds to more vibrant colors.
Saturation Min
The minimum color saturation to use. Each trailing will be given a saturation value between this minimum and Saturation Max.
Saturation Max
The maximum color saturation to use. Each trailing will be given a saturation value between Saturation Min and this maximum.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Value
When this checkbox is turned on, the value of the color will be varied per trailing. Value controls color brightness, with lower values producing darker colors.
Value Min
Minimum value to use for colors. Each trailing will be given a value between this minimum and Value Max.
Value Max
Maximum value to use for colors. Each trailing will be given a value between Value Min and this maximum. The maximum to decrease the intensity from Color.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Noise Color
Sets the color value based on a noise pattern. The generated one-dimensional noise pattern is mapped through the Color Over Noise ramp.
Mix Strength
Use Mix Strength to blend between the base color and the color generated by the noise pattern. The default value of 1 means that the noise color will overwrite the base color.
Size
Controls base feature size of the generated noise. The value applies to each axis.
Offset
The offset into the noise field. Change the value of the Offset if the current noise pattern is undesirable.
Roughness
The scale increment between iterations of fractal noise. Higher values of Roughness produce finer details in the noise, while lower values yield a smoother noise field.
Color Over Noise
A one-dimensional noise value is generated for each point. Color Over Noise ramp specifies how this single number is converted to a color. Left and right sides of this ramp correspond to noise values of 0 and 1, respectively.
Start Frame
Offsets the start frame value only for this burst component from the value set by Start Frame on the Burst Animation tab. Use this to shift the timing of certain components for a burst. For example, you can set Start Frame to 5 to start emitting the respective component 5 frames after the initial burst triggers. Use the +/- button to quickly randomize the value per input point.
Variation
Sets the maximum allowed variation in frames. Start frame offsets will be between Start Frame and Start Frame + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Expansion Scale
Scales the outward expansion only for this burst component from the value set by Outward Expansion on the Burst Animation tab. This override is useful for making some burst components physically bigger than others. Use the +/- button to quickly randomize the value per input point.
Variation
Sets the maximum allowed variation. Expansion scales will fall between Expansion Scale - Variation to Expansion Scale + Variation.
Seed
Controls random selection for variation. Change the value of the Seed if the current variation is undesirable.
Seed Offset
When this checkbox is turned on, it shifts the global Shape Offset by this amount for this component. Use this to create shape variation between burst components.
Output Attributes ¶
This tab controls additional attributes that can be generated by this node. Source Attributes are the ones needed for rasterization, while Generic Attributes control other attributes you might need for custom adjustments.
Source Attribute
When this checkbox is turned on, this string attribute will be created to isolate only the relevant points for each output volume. For example, when rasterizing the burn attribute, only points whose Source Attribute value has burn in it will be considered.
Particle Scale
When this checkbox is turned on, a pscale point attribute will be created to store the representative size of each generated source point. Particle Scale acts as a multiplier for values of this attribute.
Velocity
When this checkbox is turned on, output points will have a v point attribute storing their velocity. Velocity acts as a multiplier for values of the v attribute.
Add Velocity Noise
Adds noise to the generated velocity values. Use this to break up the velocity field and produce more interesting motion during the simulation.
Amplitude
Sets how much to change the generated velocity values. When set to 0, the noise will have no effect.
Size
Controls base feature size of the generated noise. The value applies to each axis.
Offset
The offset into the noise field. Change the value of the Offset if the current noise pattern is undesirable.
Roughness
The scale increment between iterations of fractal noise. Higher values of Roughness produce finer details in the noise, while lower values yield a smoother noise field.
Copy Input Attributes
Copies custom created point attributes from the input points to the generated points. This will ignore copying all internally used attributes.
Attributes
Only copy attributes whose names match this pattern. The default * copies all attributes. This will ignore copying all internally used attributes.
Normalized Age
The point attribute storing a zero to one value which start to increase from 0 when the burst component is created until 1 when the burst component is killed.
Trailing Position
The point attribute storing the position of each source point along its trailing.
Rest Position
When this checkbox is turned on, it creates an attribute to store the position of each point at the start of the burst. Unlike P, the rest position will not change as the burst points move.
Randomization Attribute
When this checkbox is turned on, the burstid point attribute will be created to store the value used by the Randomization By parameter.
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