KBE3D / KBCore / Cesium / PrimitiveCollection

类: PrimitiveCollection

A collection of primitives. This is most often used with Scene#primitives, but <code>PrimitiveCollection</code> is also a primitive itself so collections can be added to collections forming a hierarchy.

示例

const billboards = new Cesium.BillboardCollection();
const labels = new Cesium.LabelCollection();

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

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

参数

Object with the following properties:

参数

Determines if the primitives in the collection will be shown.

参数

Determines if primitives in the collection are destroyed when they are removed.

属性

show

show: boolean

Determines if primitives in this collection will be shown.

---

destroyPrimitives

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.

Examples

// Example 1. Primitives are destroyed by default.
const primitives = new Cesium.PrimitiveCollection();
const labels = primitives.add(new Cesium.LabelCollection());
primitives = primitives.destroy();
const b = labels.isDestroyed(); // true

// Example 2. Do not destroy primitives in a collection.
const primitives = new Cesium.PrimitiveCollection();
primitives.destroyPrimitives = false;
const labels = primitives.add(new Cesium.LabelCollection());
primitives = primitives.destroy();
const b = labels.isDestroyed(); // false
labels = labels.destroy();    // explicitly destroy

---

length

readonly length: number

Gets the number of primitives in the collection.

---

primitiveAdded

readonly primitiveAdded: Event

An event that is raised when a primitive is added to the collection. Event handlers are passed the primitive that was added.

---

primitiveRemoved

readonly primitiveRemoved: Event

An event that is raised when a primitive is removed from the collection. Event handlers are passed the primitive that was removed. <p> Note: Depending on the destroyPrimitives constructor option, the primitive may already be destroyed. </p>

方法

add()

add(primitive: any, index?: number): any

Adds a primitive to the collection.

参数

primitive

any

The primitive to add.

index?

number

The index to add the layer at. If omitted, the primitive will be added at the bottom of all existing primitives.

返回

any

The primitive added to the collection.

示例

const billboards = scene.primitives.add(new Cesium.BillboardCollection());

---

remove()

remove(primitive?: any): boolean

Removes a primitive from the collection.

参数

primitive?

any

The primitive to remove.

返回

boolean

true if the primitive was removed; false if the primitive is undefined or was not found in the collection.

示例

const billboards = scene.primitives.add(new Cesium.BillboardCollection());
scene.primitives.remove(billboards);  // Returns true

---

removeAll()

removeAll(): void

Removes all primitives in the collection.

返回

void

---

contains()

contains(primitive?: any): boolean

Determines if this collection contains a primitive.

参数

primitive?

any

The primitive to check for.

返回

boolean

true if the primitive is in the collection; false if the primitive is undefined or was not found in the collection.

---

raise()

raise(primitive?: any): void

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.

参数

primitive?

any

The primitive to raise.

返回

void

---

raiseToTop()

raiseToTop(primitive?: any): void

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.

参数

primitive?

any

The primitive to raise the top.

返回

void

---

lower()

lower(primitive?: any): void

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.

参数

primitive?

any

The primitive to lower.

返回

void

---

lowerToBottom()

lowerToBottom(primitive?: any): void

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.

参数

primitive?

any

The primitive to lower to the bottom.

返回

void

---

get()

get(index: number): any

Returns the primitive in the collection at the specified index.

参数

index

number

The zero-based index of the primitive to return.

返回

any

The primitive at the index.

示例

// Toggle the show property of every primitive in the collection.
const primitives = scene.primitives;
const length = primitives.length;
for (let i = 0; i < length; ++i) {
  const p = primitives.get(i);
  p.show = !p.show;
}

---

isDestroyed()

isDestroyed(): boolean

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

返回

boolean

True if this object was destroyed; otherwise, false.

---

destroy()

destroy(): void

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. <br /><br /> 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. <br /><br /> Once this collection is destroyed, it should not be used; calling any function other than <code>isDestroyed</code> will result in a DeveloperError exception. Therefore, assign the return value (<code>undefined</code>) to the object as done in the example.

返回

void

示例

primitives = primitives && primitives.destroy();

构造函数

构造函数

new PrimitiveCollection(options?: { show?: boolean; destroyPrimitives?: boolean; }): PrimitiveCollection

参数

options?

show?

boolean

destroyPrimitives?

boolean

返回

PrimitiveCollection