ParticleTraceGroup

class cee.ug.ParticleTraceGroup()

Specification of a particle trace group (both parameters and attributes) in a RemoteModel.

To visualize features of a vector field, it is possible to define streamlines: the paths of massless particles through the flow. Streamlines can be computed based on the specification of single points. Animating the movement of particles along these streamlines gives a powerful and direct tool for visualizing the features of a flow.

Particle traces are defined by a vector result specifying the vector field and an array of trace seed points. The particles traces use 3D primitives such as cylinders, spheres, or comets to visualize the traces. A scalar result can be mapped as fringes onto these primitives.

Particle traces can be animated. All particle trace groups must have the same number of animation steps. You specify this with Animation.particleTraceAnimationStepCount. You can start the animation with Animation.runParticleTraceAnimation.

To create a particle trace group, use RemoteModel.addParticleTraceGroup.

Example: Show a grid of traces

var modelDir = myModel.modelDirectory;

// Create a grid of 10x10 points to use a seed points
var center = new cee.Vec3(-0.017, -0.00726, 0.0016);
var seedPoints = cee.ug.ParticleTraceUtils.computeGridPoints(center,
                 new cee.Vec3(1,0,0), 10, 10, 0.0005);

// Create the particle trace group
var ptGroup = myModel.addParticleTraceGroup();
ptGroup.seedPointArray = seedPoints;
ptGroup.vectorResultId = modelDir.vectorResultArray[0].id;
ptGroup.mapScalarResultId = modelDir.scalarResultArray[0].id;
ptGroup.radius = 0.00015;

// Set model to outline to show the cutting planes
myModel.setDrawStyleAllParts(cee.ug.DrawStyle.OUTLINE);

This code sample produces the following image in the 3D Viewer:

None

Accessors

cee.ug.ParticleTraceGroup.color()
get color(): Color3Like

The color of the particle traces. This property only applies if mapScalarResultId is set to -1.

The default is white (1,1,1)

Returns: Color3Like

set color(clr: Color3Like): void

Parameters

Returns: void

cee.ug.ParticleTraceGroup.extrapolateRatioLength()
get extrapolateRatioLength(): number

The ratio length relative to the frame bounding box to test when moving out of the part

This controls how far to extrapolate the particle trace when leaving a part and entering another part The Ratio is given as a fraction of the bounding box of the current frame.

Returns: number

set extrapolateRatioLength(ratio: number): void

Parameters

ratio: number

Returns: void

cee.ug.ParticleTraceGroup.id()
get id(): number

The id of the particle trace group. This is assigned by the system when you call RemoteModel.addParticleTraceGroup and is used to identify the group.

Returns: number

cee.ug.ParticleTraceGroup.ignoreClipping()
get ignoreClipping(): boolean

Set whether the particle traces in this group should ignore clipping.

The default is false, which means that the traces will be clipped.

Returns: boolean

set ignoreClipping(ignore: boolean): void

Parameters

ignore: boolean

Returns: void

cee.ug.ParticleTraceGroup.isPrecomputed()
get isPrecomputed(): boolean

Is true if the particle trace group is precomputed and cannot be changed

Returns: boolean

cee.ug.ParticleTraceGroup.mapScalarResultId()
get mapScalarResultId(): number

The id of the scalar result to show on the particle traces.

This id must refer to one of the scalar results in ModelDirectory.scalarResultArray. You can change the settings for the scalar with the ScalarSettings object.

Set to -1 to show no scalars on the traces. In this case the value of color will be applied.

Returns: number

set mapScalarResultId(resultId: number): void

Parameters

resultId: number

Returns: void

cee.ug.ParticleTraceGroup.massedParticleParameters()
get massedParticleParameters(): MassedParticleParameters

Massed particle trace parameters.

If these paramers are set (not undefined), the particle traces will be computed based on massed particles with the given properties.

Returns: MassedParticleParameters

set massedParticleParameters(params: MassedParticleParameters): void

Parameters

Returns: void

cee.ug.ParticleTraceGroup.maximumNumberOfPointsToCompute()
get maximumNumberOfPointsToCompute(): number

Sets the maximum number of points to compute for this group

This controls the maximum number of increments that will be computed for each trace in this group.

Returns: number

set maximumNumberOfPointsToCompute(ratio: number): void

Parameters

ratio: number

Returns: void

cee.ug.ParticleTraceGroup.pointSamplingPulseCount()
get pointSamplingPulseCount(): number

Spheres and comets are emitted at regular intervals. This value specifies how many pulses there should be in the model.

The default is 5.

Returns: number

set pointSamplingPulseCount(numPulses: number): void

Parameters

numPulses: number

Returns: void

cee.ug.ParticleTraceGroup.radius()
get radius(): number

The radius of the particle trace geometry (cylinder, sphere, comet), in world coordinates.

The default is 0.005 of the extent of the bounding box.

Returns: number

set radius(radius: number): void

Parameters

radius: number

Returns: void

cee.ug.ParticleTraceGroup.relativeCometLength()
get relativeCometLength(): number

The length of the tail of the comets. It is specified in time and is a fraction of the global total time range for all particles in this group.

For example, if the total trace time is 2, and the relativeCometLength is 0.01, then the length of the tail will be 0.02.

The default is 0.1

Returns: number

set relativeCometLength(relLength: number): void

Parameters

relLength: number

Returns: void

cee.ug.ParticleTraceGroup.seedPointArray()
get seedPointArray(): readonly  Vec3Like[]

An array of seed points. Each point will result in a particle trace going through the point. If traceBothDirections is set to true, the trace will be computed both forwards and backwards from this point. If it set to false, only the forward computation will be done. All traces share the same settings, as defined by other properties of the ParticleTraceGroup.

You can use the ParticleTraceUtils.computeGridPoints static function to generate a grid of points based on a point and normal.

Returns: readonly  Vec3Like[]

set seedPointArray(pointArr: readonly  Vec3Like[]): void

Parameters

pointArr: readonly  Vec3Like[]

Returns: void

cee.ug.ParticleTraceGroup.traceBothDirections()
get traceBothDirections(): boolean

If set to true, the trace will be computed both forwards and backwards from the seed point(s).

If set to false, the trace will only be computed forwards from the seed point(s).

Returns: boolean

set traceBothDirections(bothDirections: boolean): void

Parameters

bothDirections: boolean

Returns: void

cee.ug.ParticleTraceGroup.vectorResultId()
get vectorResultId(): number

The vector result to compute the traces in. This property is mandatory and must refer to one of the vector results in ModelDirectory.vectorResultArray.

Returns: number

set vectorResultId(resultId: number): void

Parameters

resultId: number

Returns: void

cee.ug.ParticleTraceGroup.visible()
get visible(): boolean

Visibility of the particle trace group. Use this to show or hide a particle trace group in the 3D Viewer.

Returns: boolean

set visible(visible: boolean): void

Parameters

visible: boolean

Returns: void

cee.ug.ParticleTraceGroup.visualizationStyle()
get visualizationStyle(): ParticleTraceVisualizationStyle

The visualization type to use for the particle traces. This can be set to cylinders, spheres or comets.

Returns: ParticleTraceVisualizationStyle

set visualizationStyle(style: ParticleTraceVisualizationStyle): void

Parameters

Returns: void

Methods

cee.ug.ParticleTraceGroup.getAsProperties()
getAsProperties(): ParticleTraceGroupProperties

Gets the settings for this particle trace group as a Plain Old JavaScript Object (POJO).

Returns: ParticleTraceGroupProperties

cee.ug.ParticleTraceGroup.setFromProperties()
setFromProperties(props: Partial): void

Applies the settings in the given properties object to this particle trace group

Parameters

props: Partial

Returns: void