VDB Visualize Velocity Copernicus node

Traces streamers through a velocity VDB.

On this page	Parameters Inputs Outputs
Since	21.0

This operation visualizes a Velocity VDB by tracing trails through it. The result is geometry of the polylines and points of the streamers.

Parameters ¶

Trail per Voxel

Instead of scattering a fixed number of streamers, every voxel in the plane is used as a streamer source. This can get heavy with high resolutions.

Number Trails

Scatter a fixed number of streamer sources in the source plane. This ensures the density is the same regardless of resolution, so the visualization does not become too slow or crowded.

Plane

What axis to extract from the volume. This is local to the volume’s space. Rotated or transformed volumes will have a corresponding rotated or transformed plane.

Relative Location

Controls if the slicing plane will be relative to the volume or in world coordinates. Relative ensures that volumes will always generate a slice through their data; but absolute ensures that animated volumes don’t have their slices jump around.

Position

The center of the point to start slicing from when in world coordinate mode.

Offset

Where the plane should be positioned inside the volume. In Relative Location mode, this is a relative coordinate, with -1..1 being the total range, so 0 means the center of the volume.

In world coordinate mode, this is added to the world-axis perpendicular to the selected plane. Note that if the volume is rotated this will not align with the volume’s axes.

Trail Length

How long the trail should be in seconds.

Maximum Velocity

The speed of each point on the trail is visualized after dividing by the maximum velocity.

Inputs ¶

A Vector VDB of velocities to trace streamers in.

Outputs ¶

trail

A Geometry containing streamers through the provided velocity VDB.

See also

Copernicus nodes

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Bake Geometry Textures

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Blend

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Block Begin

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Block End

End of a block, declaring its outputs.
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Cable Pack

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Crop

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Cryptomatte Decode

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Derivative

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Distort

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Dot Product

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Edge Detect by Normal

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Error

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Feather

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Fetch

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File

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Fill Connected

Flood fills the connected regions of a layer.
Flip

Flips a layer horizontally, vertically, or diagonally.
Flow Block Begin

Start of a Flow simulation block.
Flow Block End

End of a Flow simulation block.
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Font

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Fractal Noise

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Fractal Noise 3D

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Function

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Geometry to Layer

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Glow

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HSV Adjust

Converts between RGB and HSV color spaces, or modifies HSV.
Heat Distort

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Heat Distort by Layer

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Height to Normal

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Height to Shadow

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HeightField Visualize

Visualizes layers as colored heightfields.
Hex Tile

Randomly tiles texture.
Histogram

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Hyperbolic Tile

Generates hyperbolic polygon tiles for texture patterns.
ID to Mask

Creates a mask from an ID layer based on filtering parameters.
ID to Mono

Converts an ID layer into a mono layer.
ID to RGB

Converts an ID layer into an RGB layer.
ID to SDF

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Illegal Pixel

Detects and then fixes or highlights illegal pixels in images.
Input

Fetches the input to a subnetwork.
Integrate Volume

Simple integration of a VDB along camera rays.
Invert

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Invoke Block

Runs a block using inputs plugged into this node.
Invoke Geometry

Runs a program saved into geometry using inputs plugged into this node.
Julia Fractal

Computes the Julia set to create a fractal.
Kuwahara Filter

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Lattice Deform

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Layer

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Layer Attribute Create

Adds or edits user-defined metadata on a layer.
Layer Attribute Delete

Removes user-defined metadata from a layer.
Layer Properties

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Layer from Curves

Render Curves into a Layer.
Layer from VDB

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Layer to Geometry

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Layer to Points

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Lens Distort

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Light

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Live Video

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Mask from Curves

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Match Camera

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Match UDIM

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Median

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Mirror

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Mono

Converts a layer to mono.
Mono to ID

Converts a mono layer into an ID layer.
Mono to RGB

Converts a mono layer into an RGB layer.
Mono to RGBA

Converts a mono layer into an RGBA layer.
Mono to SDF

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OCIO Transform

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ONNX Inference

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OpenCL

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Output

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Pixelate

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Polar to UV

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Position Map

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Position Sample

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Preview Material

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Changes the activation of VDBs in a Pyro simulation.
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Applies a force around an axis to a velocity VDB.
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Start of a Pyro simulation block.
Pyro Block End

End of a Pyro simulation block.
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Configures a Pyro simulation.
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Pyro Disturbance

Applies disturbance to a velocity VDB to break up still air.
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Pyro Source from Points

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Pyro Turbulence

Apply turbulence to a velocity VDB.
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RGBA to RGB

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RGBA to UV

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Rasterize Geometry

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Rasterize Volume

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Ray Trace

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Reaction-Diffusion Block Begin

Start of a Reaction-Diffusion simulation block.
Reaction-Diffusion Block End

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Remap

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Resample

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SDF Blend

Combines two Mono SDF layers.
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SDF to RGB

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Imports SOP geometry into Copernicus.
SOP Invoke

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SOP Invoke Graph

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Scatter Shapes

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Scatter on Curves

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Segment by Connectivity

Segment a layer into connected components.
Segment by Value

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Sequence Blend

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Sharpen

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Slap Comp Import

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Slope Direction

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Smooth Fill

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Solve Poisson Multigrid

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Space Transform

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Stamp Points

Stamps layers from point positions.
Stash

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Statistics

Outputs the average, minimum and maximum values of the input layer
Statistics by ID

Compute statistics for each ID island.
Streak Blur

Streaks an image, adding a motion blur effect.
Subnetwork

Used to organize a collection of COPs into one node.
Surface Dither

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Swirl

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Switch

Selects an input layer.
Switch If Wired

Selects an input based on what is connected.
Switch by Type

Selects an output layer by the type of the inputs.
Tile Pattern

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Tone Map

Applies a filmic tone mapping curve to compress a high dynamic range input into a displayable range.
Transform 2D

Transforms a layer in 2D.
Transform 3D

Transforms a layer in 3D.
Triplanar

Generates a texture by projecting X, Y, and Z textures onto the position layer.
Triplanar Hex Tile

Seamless texturing and normal mapping of triplanar projections without visible repetitions.
Triplanar UV

Generates UVs in three orthogonal projections.
Two Way Switch If Wired

Selects between two inputs based on if you wire in another input.
UV Map

Generates a UV Map.
UV Map by ID

Creates a UV Map for each connected ID island.
UV Sample

Samples an input layer using a UV layer.
UV Transform

Transforms the values of a UV layer in 2d space.
UV to Polar

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UV to RGB

Joins a UV and mono layer into an RGB layer.
UV to RGBA

Joins two UV layers into an RGBA layer.
VDB Activate from Points

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VDB Leaf Points

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VDB Position Map

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VDB Reshape

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VDB Visualize

Creates multi-volume visualization.
VDB Visualize Slice

Extracts a slice from a VDB as Geometry for visualization.
VDB Visualize Tree

Builds a geometry visualizing the topology of a VDB.
VDB Visualize Velocity

Traces streamers through a velocity VDB.
VDB from Layer

Sets VDB values from the closest values in a layer.
Vector Transform

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Vector Transform 2D

Transforms the values of a UV layer in 2D space.
Vignette

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Wipe

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Worley Noise

Generates Worley noise.
Worley Noise 3D

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Wrangle

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Z Composite

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