Module: Particle Pathlines ()

Description:

This module displays as a set of particles a 3D vector field (HxVectorField3). When connected to a Time Series Control module, particles are animated. Each particle is evaluated in the vector field and moves according to the vector direction and velocity. Therefore, the animation of the particles actually corresponds to a motion in time and pathlines can be represented, contrary to particles displayed in Particle Plot or streamlines in Illuminated Streamlines, which correspond to the interpretation of an instantaneous capture of the flow.

When velocities are expressed in m/s, they are converted to geodetic coordinates (lon, lat) before being interpreted, since the location coordinates of these velocities are also in geodetic. The conversion consists of a scale depending on the [lon,lat] location, thus different for all particles.

When a scalar field is connected to the colorfield port, particles color are evaluated according to this colorField. Otherwise, colors are taken from the length of the direction vectors.

Connections:

Data [required]
HxVectorField3 representing the vectors that handle direction and velocity of particles. Direction is used for particles trajectories. Length is used for particles velocity.

Colorfield [optional]
An optional scalar field which, if present, will be used for pseudo-coloring. It is usually useful to create a scalar field from the vector field using the Magnitude module.

Colormap [optional]
Associated colormap. This port is hidden if the Data or Colorfield port is connected to an Unstructured Model Field. In that case, the colormap of the data set is used for the display.

Ports:

Scale factor

This port controls the scale applied to the particles.

Size factor

This port controls the size (in the direction) applied to the particles.

Value factor

This port controls the multiplicated factor applied to the particle velocity.

Resolution

This port handles the regular distribution of particles in the field bounding box.

Reset

When hit, this button replace the particles at their original location.

Options

Glyph used to display a particle

• Sphere
• Cone

Interpolation used to compute particles trajectory

• Simple Euler interpolation.
• Complex Runge Kutta interpolation.

Direction parameters to display particles

• None particles have no direction.
• Use particles are oriented according to direction vector with uniform length.
• Use as length particles are oriented according to direction vector with corresponding length.

Border

This port controls the particles behaviour when the trajectory is out of the bounding box.

• Continuous if set, particles can move from X positive border to X negative border and reverse.
• Clamp if set, particles positions are limited to the Y borders of the field.

Trajectory

This port handles the trajectory properties of the particles.

Shape style controls the shape displayed to represent the trajectory

• None No trajectory is displayed.
• Line Displays trajectory as a line.
• Extrusion Displays trajectory as an extrusion.

Keep trace: when checked, trajectories of particles gone out of field bounding box are still displayed.

Colormap

Associated colormap used to colorize the particles. See Connections section.

Box

This port is only displayed in projection mode. This port controls the projected seed box of the particles. The seed box is composed of a black shape representation and green little boxes that handle the manipulation. When active, the seed box determines the origin of the particles. Pressing reset resizes the box to the bounding box of the connected data.

When projecting the particles (see Projection Settings), only the lower left corner of the green boxes is used to compute the projected shape. Other boxes won't be synchronized with the box geometry.

Box center

This port is only displayed in projection mode. This port controls the center of the projected seed box. When projecting the particles, it can happen that the value entered be erroneous. In that case, the old value is displayed again.

Box scale

This port is only displayed in projection mode. This port controls the scale factor of the projected seed box. When projecting the particles, it can happen that the value entered be erroneous. In that case, the old value is displayed again.