PrimitiveCollection

new Cesium.PrimitiveCollection(options)

A collection of primitives. This is most often used with Scene#primitives, but PrimitiveCollection is also a primitive itself so collections can be added to collections forming a hierarchy.
Name Type Description
options Object optional Object with the following properties:
Name Type Default Description
show Boolean true optional Determines if the primitives in the collection will be shown.
destroyPrimitives Boolean true optional Determines if primitives in the collection are destroyed when they are removed.
Example:
var billboards = new Cesium.BillboardCollection();
var labels = new Cesium.LabelCollection();

var collection = new Cesium.PrimitiveCollection();
collection.add(billboards);

scene.primitives.add(collection);  // Add collection
scene.primitives.add(labels);      // Add regular primitive

Members

destroyPrimitives : Boolean

Determines if primitives in the collection are destroyed when they are removed by PrimitiveCollection#destroy or PrimitiveCollection#remove or implicitly by PrimitiveCollection#removeAll.
Default Value: true
Examples:
// Example 1. Primitives are destroyed by default.
var primitives = new Cesium.PrimitiveCollection();
var labels = primitives.add(new Cesium.LabelCollection());
primitives = primitives.destroy();
var b = labels.isDestroyed(); // true
// Example 2. Do not destroy primitives in a collection.
var primitives = new Cesium.PrimitiveCollection();
primitives.destroyPrimitives = false;
var labels = primitives.add(new Cesium.LabelCollection());
primitives = primitives.destroy();
var b = labels.isDestroyed(); // false
labels = labels.destroy();    // explicitly destroy

readonlylength : Number

Gets the number of primitives in the collection.
Determines if primitives in this collection will be shown.
Default Value: true

Methods

add(primitive)Object

Adds a primitive to the collection.
Name Type Description
primitive Object The primitive to add.
Returns:
The primitive added to the collection.
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
Example:
var billboards = scene.primitives.add(new Cesium.BillboardCollection());

contains(primitive)Boolean

Determines if this collection contains a primitive.
Name Type Description
primitive Object optional The primitive to check for.
Returns:
true if the primitive is in the collection; false if the primitive is undefined or was not found in the collection.
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
See:

destroy()undefined

Destroys the WebGL resources held by each primitive in this collection. Explicitly destroying this collection allows for deterministic release of WebGL resources, instead of relying on the garbage collector to destroy this collection.

Since destroying a collection destroys all the contained primitives, only destroy a collection when you are sure no other code is still using any of the contained primitives.

Once this collection 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:
primitives = primitives && primitives.destroy();
See:

get(index)Object

Returns the primitive in the collection at the specified index.
Name Type Description
index Number The zero-based index of the primitive to return.
Returns:
The primitive at the index.
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
Example:
// Toggle the show property of every primitive in the collection.
var primitives = scene.primitives;
var length = primitives.length;
for (var i = 0; i < length; ++i) {
  var p = primitives.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:
Lowers a primitive "down one" in the collection. If all primitives in the collection are drawn on the globe surface, this visually moves the primitive down one.
Name Type Description
primitive Object optional The primitive to lower.
Throws:
See:

lowerToBottom(primitive)

Lowers a primitive to the "bottom" of the collection. If all primitives in the collection are drawn on the globe surface, this visually moves the primitive to the bottom.
Name Type Description
primitive Object optional The primitive to lower to the bottom.
Throws:
See:
Raises a primitive "up one" in the collection. If all primitives in the collection are drawn on the globe surface, this visually moves the primitive up one.
Name Type Description
primitive Object optional The primitive to raise.
Throws:
See:

raiseToTop(primitive)

Raises a primitive to the "top" of the collection. If all primitives in the collection are drawn on the globe surface, this visually moves the primitive to the top.
Name Type Description
primitive Object optional The primitive to raise the top.
Throws:
See:

remove(primitive)Boolean

Removes a primitive from the collection.
Name Type Description
primitive Object optional The primitive to remove.
Returns:
true if the primitive was removed; false if the primitive is undefined or was not found in the collection.
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
Example:
var billboards = scene.primitives.add(new Cesium.BillboardCollection());
scene.primitives.remove(p);  // Returns true
See:
Removes all primitives in the collection.
Throws:
  • DeveloperError : This object was destroyed, i.e., destroy() was called.
See: