PointPrimitiveCollection

new Cesium.PointPrimitiveCollection(options)

A renderable collection of points.

Points are added and removed from the collection using PointPrimitiveCollection#add and PointPrimitiveCollection#remove.
Performance:

For best performance, prefer a few collections, each with many points, to many collections with only a few points each. Organize collections so that points with the same update frequency are in the same collection, i.e., points that do not change should be in one collection; points 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 point from model to world coordinates.
debugShowBoundingVolume Boolean false optional For debugging only. Determines if this primitive's commands' bounding spheres are shown.
blendOption BlendOption BlendOption.OPAQUE_AND_TRANSLUCENT optional The point blending option. The default is used for rendering both opaque and translucent points. However, if either all of the points are completely opaque or all are completely translucent, setting the technique to BillboardRenderTechnique.OPAQUE or BillboardRenderTechnique.TRANSLUCENT can improve performance by up to 2x.
Example:
// Create a pointPrimitive collection with two points
var points = scene.primitives.add(new Cesium.PointPrimitiveCollection());
points.add({
  position : new Cesium.Cartesian3(1.0, 2.0, 3.0),
  color : Cesium.Color.YELLOW
});
points.add({
  position : new Cesium.Cartesian3(4.0, 5.0, 6.0),
  color : Cesium.Color.CYAN
});
See:

Members

blendOption : BlendOption

The point blending option. The default is used for rendering both opaque and translucent points. However, if either all of the points are completely opaque or all are completely translucent, setting the technique to BillboardRenderTechnique.OPAQUE or BillboardRenderTechnique.TRANSLUCENT can improve performance by up to 2x.
Default Value: BlendOption.OPAQUE_AND_TRANSLUCENT

debugShowBoundingVolume : Boolean

This property is for debugging only; it is not for production use nor is it optimized.

Draws the bounding sphere for each draw command in the primitive.

Default Value: false

length : Number

Returns the number of points in this collection. This is commonly used with PointPrimitiveCollection#get to iterate over all the points in the collection.

modelMatrix : Matrix4

The 4x4 transformation matrix that transforms each point in this collection from model to world coordinates. When this is the identity matrix, the pointPrimitives are drawn in world coordinates, i.e., Earth's WGS84 coordinates. Local reference frames can be used by providing a different transformation matrix, like that returned by Transforms.eastNorthUpToFixedFrame.
Default Value: Matrix4.IDENTITY
Example:
var center = Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883);
pointPrimitives.modelMatrix = Cesium.Transforms.eastNorthUpToFixedFrame(center);
pointPrimitives.add({
  color : Cesium.Color.ORANGE,
  position : new Cesium.Cartesian3(0.0, 0.0, 0.0) // center
});
pointPrimitives.add({
  color : Cesium.Color.YELLOW,
  position : new Cesium.Cartesian3(1000000.0, 0.0, 0.0) // east
});
pointPrimitives.add({
  color : Cesium.Color.GREEN,
  position : new Cesium.Cartesian3(0.0, 1000000.0, 0.0) // north
});
pointPrimitives.add({
  color : Cesium.Color.CYAN,
  position : new Cesium.Cartesian3(0.0, 0.0, 1000000.0) // up
});
See:

Methods

add(pointPrimitive) → PointPrimitive

Creates and adds a point with the specified initial properties to the collection. The added point is returned so it can be modified or removed from the collection later.
Performance:

Calling add is expected constant time. However, the collection's vertex buffer is rewritten - an O(n) operation that also incurs CPU to GPU overhead. For best performance, add as many pointPrimitives as possible before calling update.

Name Type Description
pointPrimitive Object optional A template describing the point's properties as shown in Example 1.
Returns:
The point that was added to the collection.
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
Examples:
// Example 1:  Add a point, specifying all the default values.
var p = pointPrimitives.add({
  show : true,
  position : Cesium.Cartesian3.ZERO,
  pixelSize : 10.0,
  color : Cesium.Color.WHITE,
  outlineColor : Cesium.Color.TRANSPARENT,
  outlineWidth : 0.0,
  id : undefined
});
// Example 2:  Specify only the point's cartographic position.
var p = pointPrimitives.add({
  position : Cesium.Cartesian3.fromDegrees(longitude, latitude, height)
});
See:

contains(pointPrimitive) → Boolean

Check whether this collection contains a given point.
Name Type Description
pointPrimitive PointPrimitive optional The point to check for.
Returns:
true if this collection contains the point, false otherwise.
See:

destroy() → undefined

Destroys the WebGL resources held by this object. Destroying an object allows for deterministic release of WebGL resources, instead of relying on the garbage collector to destroy this object.

Once an object is destroyed, it should not be used; calling any function other than isDestroyed will result in a DeveloperError exception. Therefore, assign the return value (undefined) to the object as done in the example.
Returns:
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
Example:
pointPrimitives = pointPrimitives && pointPrimitives.destroy();
See:

get(index) → PointPrimitive

Returns the point in the collection at the specified index. Indices are zero-based and increase as points are added. Removing a point shifts all points after it to the left, changing their indices. This function is commonly used with PointPrimitiveCollection#length to iterate over all the points in the collection.
Performance:

Expected constant time. If points were removed from the collection and PointPrimitiveCollection#update was not called, an implicit O(n) operation is performed.

Name Type Description
index Number The zero-based index of the point.
Returns:
The point at the specified index.
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
Example:
// Toggle the show property of every point in the collection
var len = pointPrimitives.length;
for (var i = 0; i < len; ++i) {
  var p = pointPrimitives.get(i);
  p.show = !p.show;
}
See:

isDestroyed() → Boolean

Returns true if this object was destroyed; otherwise, false.

If this object was destroyed, it should not be used; calling any function other than isDestroyed will result in a DeveloperError exception.
Returns:
true if this object was destroyed; otherwise, false.
See:

remove(pointPrimitive) → Boolean

Removes a point from the collection.
Performance:

Calling remove is expected constant time. However, the collection's vertex buffer is rewritten - an O(n) operation that also incurs CPU to GPU overhead. For best performance, remove as many points as possible before calling update. If you intend to temporarily hide a point, it is usually more efficient to call PointPrimitive#show instead of removing and re-adding the point.

Name Type Description
pointPrimitive PointPrimitive The point to remove.
Returns:
true if the point was removed; false if the point was not found in the collection.
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
Example:
var p = pointPrimitives.add(...);
pointPrimitives.remove(p);  // Returns true
See:

removeAll()

Removes all points from the collection.
Performance:

O(n). It is more efficient to remove all the points 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:
pointPrimitives.add(...);
pointPrimitives.add(...);
pointPrimitives.removeAll();
See: