| 参数名称 | 类型 | 描述信息 | ||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
options |
object |
|
Experimental
This feature is not final and is subject to change without Cesium's standard deprecation policy.
参考:
成员(属性)
boundingVolume : BoundingSphere
Bounding volume for all primitives in the collection, including both
shown and hidden primitives.
Total byte length of buffers owned by this collection. Includes any unused
space allocated by
primitiveCountMax, even if no primitives have
yet been added in that space.
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.
-
默认值:
false
Default capacity of buffers on new collections. A quantity of elements:
number of vertices in the vertex buffer, primitives in the primitive
buffer, etc. This value is arbitrary, and collections cannot be resized,
so specific per-buffer capacities should be provided in the collection
constructor when available.
Number of primitives in collection. Must be <=
primitiveCountMax.
Maximum number of primitives this collection can contain. Must be >=
primitiveCount.
-
默认值:
BufferPrimitiveCollection.DEFAULT_CAPACITY
Determines if primitives in this collection will be shown.
-
默认值:
true
Number of vertices in collection. Must be <=
vertexCountMax.
Maximum number of vertices this collection can contain. Must be >=
vertexCount.
-
默认值:
BufferPrimitiveCollection.DEFAULT_CAPACITY方法
Duplicates the contents of this collection into the result collection.
Result collection is not resized, and must contain enough space for all
primitives in the source collection. Existing primitives in the result
collection will be overwritten.
Useful when allocating more space for a collection that has reached its capacity, and efficiently transferring features to the new collection.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
collection |
BufferPrimitiveCollection.<T> | |
result |
BufferPrimitiveCollection.<T> |
使用示例:
const result = new BufferPrimitiveCollection({ ... }); // allocate larger 'result' collection
BufferPrimitiveCollection.clone(collection, result); // copy primitives from 'collection' into 'result'add(options, result) → BufferPrimitive
Adds a new primitive to the collection, with the specified options. A
BufferPrimitive instance is linked to the new primitive, using
the 'result' argument if given, or a new instance if not. For repeated
calls, prefer to reuse a single BufferPrimitive instance rather than
allocating a new instance on each call.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
options |
BufferPrimitiveOptions | |
result |
BufferPrimitive |
返回值:
get(index, result) → BufferPrimitive
Makes the given
BufferPrimitive a view onto this collection's
primitive at the given index, for use when reading/writing primitive
properties. When iterating over a large collection, prefer to reuse
the same BufferPrimitive instance throughout the loop — rebinding
an existing instance to a different primitive is cheap, and avoids
allocating in-memory objects for every object.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
index |
number | |
result |
BufferPrimitive |
返回值:
The BufferPrimitive instance passed as the
'result' argument, now bound to the specified primitive index.
使用示例:
const primitive = new BufferPrimitive();
for (let i = 0; i < collection.primitiveCount; i++) {
collection.get(i, primitive);
primitive.setColor(Color.RED);
}
Returns true if this object was destroyed; otherwise, false.
返回值:
True if this object was destroyed; otherwise, false.
Sorts primitives of the collection.
Because sorting changes the indices (but not the feature IDs) of primitives
in the collection, the function also returns an array mapping from previous
index to new index. When sorting repeatedly, the array can be reused and
passed as the 'result' argument for each call.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
sortFn |
function | |
result |
Uint32Array |
返回值:
Mapping from previous index to new index.
Returns a JSON-serializable array representing the collection. This encoding
is not memory-efficient, and should generally be used for debugging and
testing.
返回值:
List of JSON-serializable objects, one for each
primitive in the collection.
使用示例:
console.table(collection.toJSON());| 参数名称 | 类型 | 描述信息 |
|---|---|---|
frameState |
object |