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Unity Engine


Unity Engine


BlobBuilder

Creates blob assets.
Read time 2 minutesLast updated 2 days ago

Definition

public struct BlobBuilder : IDisposable

Remarks

A blob asset is an immutable data structure stored in unmanaged memory. Blob assets can contain primitive types, strings, structs, arrays, and arrays of arrays. Arrays and structs must only contain blittable types. Strings must be of type BlobString (or a specialized unmanaged string type).
To use a BlobBuilder object to create a blob asset:
  1. Declare the structure of the blob asset as a struct.
  2. Create a BlobBuilder object.
  3. Call the BlobBuilder.ConstructRoot method, where
    T
    is the struct defining the asset structure.
  4. Initialize primitive values defined at the root level of the asset.
  5. Allocate memory for arrays, structs, and BlobString instances at the root.
  6. Initialize the values of those arrays, structs, and strings.
  7. Continue allocating memory and initializing values until you have fully constructed the asset.
  8. Call BlobBuilder.CreateBlobAssetReference to create a reference to the blob asset in memory.
  9. Dispose the BlobBuilder object.
Use the BlobAssetReference<T> returned by BlobBuilder.CreateBlobAssetReference to reference the blob asset. You can use a BlobAssetReference<T> as a field of an IComponentData struct. More than one entity can reference the same blob asset.
Call BlobAssetReference<T>.Dispose to free the memory allocated for a blob asset.
Blob assets cannot be modified once created. Instead, you must create a new blob asset, update any references to the old one and then dispose of it.

Constructors

Constructor

Description

BlobBuilder(Unity.Collections.AllocatorManager.AllocatorHandle,System.Int32)Constructs a BlobBuilder object.

Properties

Property

Description

IsCreatedReturns true if this BlobBuilder has been allocated.

Methods

Method

Description

AllocateAllocates enough memory to store
length
elements of struct
T
.
ConstructCopies an array of structs to an array in a blob asset after allocating the necessary memory.
ConstructRootCreates the top-level fields of a single blob asset.
CreateBlobAssetReferenceCompletes construction of the blob asset and returns a reference to the asset in unmanaged memory.
DisposeDisposes of this BlobBuilder instance and frees its temporary memory allocations.
SetPointerSets a BlobPtr to point to the given object inside the blob.