Module: Seed Surface ()

Description:

This module extends the vector field visualization module Illuminated Streamlines. It allows you to compute illuminated field lines of a vector field with seed points distributed across an arbitrary Surface.

First, load both the vector field and the surface into . Then attach Illuminated Streamlines to the vector field. From the popup menu of Illuminated Streamlines choose Seed Surface. The Seed Surface module automatically connects itself to the first surface found in the Project Tree View. Of course, you may change the surface connection at any time later on. Properties of the illuminated field lines such as base opacity, fade factor, or color will be determined by Illuminated Streamlines.

The Apply button is used to initiate distribution of seeds and recomputation of field lines. Once the incoming vector field has changed or you have modified the number of field lines or the line's length, you must press Apply again in order to update the display.

Connections:

Surface [required]
The surface on which the field lines will be distributed.

DisplayISL [required]
Module of type Illuminated Streamlines which is used to display the illuminated field lines.

Ports:

NumLines

Number of field lines to be displayed. This port will only be visible if distribution mode on surface has been selected. The distribution algorithm tries to achieve a constant seed density per surface area.

Length

The length of the field lines, or more precisely, the number of atomic line segments, in forward respectively backward direction. The lines may stop earlier if a singularity (i.e., zero magnitude) is encountered or if the field's domain is left.

Balance

By default, field lines are equally long in forward and backward direction, corresponding to a balance value of 0. This port allows you to change this behavior. A value of -1 indicates that field lines should extend in backward direction only, while a value of 1 indicates that field lines should extend in forward direction only.

Distribute

This port provides an option menu specifying the seed distribution mode. If at vertices is chosen, a field line is started at each vertex of the surface. If on surface is chosen, a user-defined number of field lines will be uniformly distributed across the surface.