The vortex template
| Parameter | Description |
|---|---|
| Appearance | Influences the appearance of spiralling vortices. They can be displayed as single or double spiral. |
| Arrow colour | Allows to specify a distinct arrow color. |
| Arrow direction | Arrows can be set to point in clockwise or counter clockwise direction, independently of the vortex style. |
| Arrow size | The size of the displayed arrow glyphs in pixels. |
| Auto adjust size | If this option is true, the extent and orientation of a vortex is measured at each time step. If this option is false, only the position of the vortex center is determined and the orientation and extent are kept fixed. |
| Center | The center of the vortex template in domain coordinates. |
| Colour | Colour used to render the vortex template. |
| Halo colour | Colour of the halo surrounding the template. Can also be used to create a contour line-e ect. |
| Number of arrows | Number of arrows displayed in the vortex template. Has to be >= 0. |
| Radius1 | Radius of the underlying ellipse parallel to the X-axis. |
| Radius2 | Radius of the underlying ellipse parallel to the Y-axis. |
| Revolutions | Number of revolutions if drawn as spiral. |
| Rotation | Rotation around the vortex center in degree, with respect to the X-axis. |
| Show trajectory | If this flag is true, the trajectory of the vortex is displayed. The trajectory starts at the current time step and extends backwards in time for Trajectory length time steps. |
| Style | Defines if a vortex template is rendered as ellipse, clock-wise spiral or counter clock-wise spiral. |
| Thickness | Line thickness used to draw the ellipse/spirals. Valid values must be >= 0. |
| Threshold | Threshold in &, relative to absolute vorticity value at the vortex core. The extent of the vortex is measured in gradient and co-gradient direction until the vorticity magnitude drops below the specified threshold. |
| Trajectory length | Length in time steps of the trajectory. |
Characteristic curve templates
| Parameter | Description |
|---|---|
| Arrow colour | Allows to specify a distinct arrow color. |
| Arrow size | The size of the arrows in pixels. |
| Colour | Colour used to render a characteristic curve. |
| Drawing style | Allows to choose between regular line-style representation, and streamlet/droplet representation. |
| Fixed start frame | Is this value is set, path line integration is started from the frame specified with Start frame, otherwise integration is started from the currently displayed frame. |
| Halo color | Colour of the halo surrounding the template. Can also be used to create a contour line-e ect. |
| Integration steps | The characteristic curve is integrated for at max this number of steps. Integration can be aborted, if e.g. integration reaches a domain boundary. |
| Line end | Second point in domain coordinates of the seeding line of a time line. |
| Line start | First point in domain coordinates of the seeding line of a time line. |
| Number of arrows | Number of arrows displayed along a characteristic curve template. Has to be 0. |
| Number of samples | Number of samples of a time line, that are uniformly spaced on the line speci ed by line start and line end. |
| Number of speed lines | Number of speed lines, used to display the trajectory of a time line. |
| Origin | Seeding point in domain coordinates from where the integration of a characteristic curve is started. |
| Render as particles | Allows to render a streak line's individual particles. |
| Show arrows | Determines if the arrows along a characteristic curve are displayed. |
| Show trajectory | If true, the trajectory of a time line is displayed. |
| Smoothness | Kernel half-size of the box lter used to smooth a characteristic curve. |
| Start frame | Positive frame number from which the integration of a path, streak or time line is started. |
| Step length | Step length multiplier for the RK4 integrator. Each particle of a time line is integrated about 1/steplength steplengh times for the transition between two consecutive time steps. |
| Step size | Step size multiplier for the RK4 integrator. |
| Thickness | Line thickness used to draw a characteristic curve. Accepted values must be >= 0. |
Geometric primitives
| Parameter | Description |
|---|---|
| Center | The center of a geometric primitive. |
| Colour | Colour of a primitive template. |
| End point | End point of a B-Spline curve in domain coordinates. |
| Height | The height of a geometric primitive in domain space. |
| Length | The length of a ow arrow in domain coordinates. |
| Number of control points | Number of control points for B-Splines curves. |
| Start point | Start point of a B-Spline curve or flow arrow in domain coordinates. |
| Style | The drawing style of a primitive template. This can be e.g. solid, outline, or hatched. |
| Width | The width of a geometric primitive. |
The speed line template
| Parameter | Description |
|---|---|
| Colour | Main colour of the speed line. Can be different from the colour of its parent object. |
| Halo colour | Halo colour of the speed line.Can be different from the colour of its parent object. |
| Transparency mode | Can be one of the following values: Constant, Increasing, decreasing. In case of increasing or decreasing, the increase/decrease of the transparency is started from the first vertex near the parent object and proceeds throughout the entire speed line. |
| Thickness mode | Can be one of the following values: Constant, Increasing, decreasing. In case of increasing or decreasing, the growing/shrinking process is started from the first vertex near the parent object and proceeds throughout the entire speed line. |
| Max thickness | The maximum thickness of the speed line. If the thickness mode is set to constant, this thickness is used as default thickness for the speed line. |
| Max transparency | The maximum transparency value of the speed line. If the transparency mode is set to constant, this value is used as default transparency value for the speed line. |
| Min thickness | The minimal thickness of a speed line. Only used, if thickness mode is set to increasing or decreasing. |
| Min transparency | The minimal transparency value of a speed line. Only used, if transparency mode is set to increasing or decreasing. |
| Number of time steps | Number of time steps used to integrate the speed line backwards in time. |
| Show trajectory | The trajectory of a moving object is only shown, if this flag is set to true. |