PolylineCollection

new Cesium.PolylineCollection(options)

Scene/PolylineCollection.js 159

A renderable collection of polylines.

Example polylines

Polylines are added and removed from the collection using PolylineCollection#add and PolylineCollection#remove.

Performance:

For best performance, prefer a few collections, each with many polylines, to many collections with only a few polylines each. Organize collections so that polylines with the same update frequency are in the same collection, i.e., polylines that do not change should be in one collection; polylines that change every frame should be in another collection; and so on.

Name	Type	Description
options	Object	optional Object with the following properties: Name Type Default Description modelMatrix Matrix4 Matrix4.IDENTITY optional The 4x4 transformation matrix that transforms each polyline from model to world coordinates. debugShowBoundingVolume Boolean false optional For debugging only. Determines if this primitive's commands' bounding spheres are shown.

Example:

// Create a polyline collection with two polylines
var polylines = new Cesium.PolylineCollection();
polylines.add({
  positions : Cesium.Cartesian3.fromDegreesArray([
    -75.10, 39.57,
    -77.02, 38.53,
    -80.50, 35.14,
    -80.12, 25.46]),
  width : 2
});

polylines.add({
  positions : Cesium.Cartesian3.fromDegreesArray([
    -73.10, 37.57,
    -75.02, 36.53,
    -78.50, 33.14,
    -78.12, 23.46]),
  width : 4
});

See:

• PolylineCollection#add
• PolylineCollection#remove
• Polyline
• LabelCollection

Members

Default Value: false

Default Value: Matrix4.IDENTITY

Methods

Performance:

After calling add, PolylineCollection#update is called and the collection's vertex buffer is rewritten - an O(n) operation that also incurs CPU to GPU overhead. For best performance, add as many polylines as possible before calling update.

Returns:

Throws:

• DeveloperError : This object was destroyed, i.e., destroy() was called.

Example:

// Example 1:  Add a polyline, specifying all the default values.
var p = polylines.add({
  show : true,
  positions : ellipsoid.cartographicArrayToCartesianArray([
           Cesium.Cartographic.fromDegrees(-75.10, 39.57),
           Cesium.Cartographic.fromDegrees(-77.02, 38.53)]),
  width : 1
});

See:

• PolylineCollection#remove
• PolylineCollection#removeAll
• PolylineCollection#update

Returns:

See:

• PolylineCollection#get

Throws:

• DeveloperError : This object was destroyed, i.e., destroy() was called.

Example:

polylines = polylines && polylines.destroy();

See:

• PolylineCollection#isDestroyed

Performance:

If polylines were removed from the collection and PolylineCollection#update was not called, an implicit O(n) operation is performed.

Returns:

Throws:

• DeveloperError : This object was destroyed, i.e., destroy() was called.

Example:

// Toggle the show property of every polyline in the collection
var len = polylines.length;
for (var i = 0; i < len; ++i) {
  var p = polylines.get(i);
  p.show = !p.show;
}

See:

• PolylineCollection#length

Returns:

See:

• PolylineCollection#destroy

Performance:

After calling remove, PolylineCollection#update is called and the collection's vertex buffer is rewritten - an O(n) operation that also incurs CPU to GPU overhead. For best performance, remove as many polylines as possible before calling update. If you intend to temporarily hide a polyline, it is usually more efficient to call Polyline#show instead of removing and re-adding the polyline.

Returns:

Throws:

• DeveloperError : This object was destroyed, i.e., destroy() was called.

Example:

var p = polylines.add(...);
polylines.remove(p);  // Returns true

See:

• PolylineCollection#add
• PolylineCollection#removeAll
• PolylineCollection#update
• Polyline#show

Performance:

O(n). It is more efficient to remove all the polylines from a collection and then add new ones than to create a new collection entirely.

Throws:

• DeveloperError : This object was destroyed, i.e., destroy() was called.

Example:

polylines.add(...);
polylines.add(...);
polylines.removeAll();

See:

• PolylineCollection#add
• PolylineCollection#remove
• PolylineCollection#update

Throws:

• RuntimeError : Vertex texture fetch support is required to render primitives with per-instance attributes. The maximum number of vertex texture image units must be greater than zero.