LW - RF Particle Importer

Owned by thomas (Unlicensed)
Last updated: 25 Jun, 2013
4 min read

The "RF Particle Importer displacement" plugin loads RealFlow particle BIN or PXY (proxy) sequence with the selected attributes. There are two ways to add a RealFlow particle system to the scene. The first method is to add the RF Particle Importer manually:

  1. Select "Items" tab and add a "Null" object to the scene, or press Ctrl/Cmd + N.
  2. Press p to open the object properties window.
  3. Select "Deform" tab.
  4. Add the "RF Particle Importer" displacement plugin.
  5. Open the GUI by double-clicking on the "RF Particle Importer" plugin.
  6. Click on the "File Path" button and select one BIN or PXY file from the sequence.

The plugin tries to recognize the name of the particle system and the padding size from the file name, and the start/end frame of the sequence. When the particles are loaded successfully, the "Null" object is renamed to the name of the particle system.

 


How to add the "RF Particle Importer" displacement plugin.

 

An alternative method to add RealFlow particles is using the "Next Limit Plug-in Manager" master plugin which executes the above steps automatically. From the master window the particles can be imported as HyperVoxel particles or as partigons with the “Import As” option. HyperVoxel particles do not have a surface, they can be rendered only with the HyperVoxel plugin as surface, volume or sprite objects. Partigons, on the other hand, act like normal objects and can be surfaced in the "Surface Editor".

Memory management and speed can be balanced via the "Cache Mode" feature which has the following options: "Current Frame", "Core Frames", "All Frames". In "Current Frame" mode the user only loads the current frame into the memory. This mode has the lowest memory usage but it reads the next file from the disc in every frame. "Core Frames" holds the neighborhood of the current frame in the memory. The core size can be dynamically set. "All Frames" caches the whole sequence.

"Start/End" frames are set automatically after a correct file path is given. Later this can be changed, so the plugin will only render the particles inside the specified interval.

"LOD" (Level of Detail) is used for filtering the particles in the viewport. Complex fluid systems can be displayed with fewer guide particles in the viewport.

Frames of the sequence can be shifted, the current frame can be locked, and also the whole sequence can be inverted.

Motion blur interpolation is supported. There are two methods for the interpolation described below.

The speed and characteristic of the animation can be controlled via an envelope called "Playback", where 0% means the start frame, 100% means the end frame of the selected animation. When the animation is changed, float frames have to be rendered from the RealFlow particle sequence, thus the particles are interpolated.You can find an example how to use the "Playback" envelope in the tutorial section.

The transformation (translation, rotation, scale) of the holder "Null" object is applied to the particles.

 


"RF Particle Importer" plugin parameters.

 

The setup properties on the "RF Particle Importer" window are as follows:

  • "File Path" is the path of one of the Real Flow particle files from the BIN or PXY sequence.
  • "Name" is a read-only field. The name of the particle system comes from the name of the RealFlow particle file and is recognized automatically when a particle file is opened.
  • "Padding" describes the padding size of the Real Flow particle file and is recognized automatically when opening a particle file.
  • "Cache Mode" defines disc and memory usage: "Current Frame" reads the current file from the disk, "Core Frames" reads frames inside the ''Cache Core'', and "All Frames" reads all frames inside the specified start/end range
  • "Cache Core" determines the radius for Core Frames mode.
  • "Level of Detail" is the level of detail of displayed particles in percent.
  • "Interpolation" describes the used method for motion blur and playback calculation: "Deform" reads the BIN file of the current and next frame and interpolates using the two values. With this method all the attributes (e.g. density or pressure) can be interpolated, except for the last frame. "Velocity" calculates float frame position by the velocity attribute. It is very fast, but the attributes are unchanged.
  • "Start frame" and "End Frame" define the start and end frame of the sequence.
  • "Offset" is the shifting of the imported sequence.
  • "Lock Current Frame" keeps the current frame displayed.
  • "Lock Last Frame" keeps the last imported frame displayed.
  • "Invert Sequence" inverts the file sequence.
  • "Playback envelope" is a flag to use envelope to control the animation.
  • "Edit…" opens the "Graph Editor" with the playback envelope.
  • "Reset" sets a linear envelope between the selected start and end frame.
  • "Viewport Interpolation" displays the interpolated particles in the viewport. Disabling this option can save time for displaying simulations with a high number of particles.

Every particle has several attributes like age, number of neighbors or physical parameters. These can be set on the "Particles" tab of the "RF Particle Importer window". The attributes are separated into two groups: vector and scalar attributes. The user can define for every attribute that he wants to keep the original value stored in the particle file ("Keep"), wants to override it by a custom expression ("Add") or does not want any value for the attribute ("No").

A particle holds the following attributes:

  • Velocity vector
  • Force vector
  • Vorticity vector
  • Normal vector
  • Texture vector
  • Number of neighbors
  • Information bit
  • Age of the particle
  • Isolation time
  • Viscosity
  • Density
  • Pressure
  • Mass
  • Temperature
  • Id of the current particle

 


RF Particle Importer attribute parameters.