# vertexAttributeData(forAttributeNamed:) Returns the vertex data for the specified attribute. ``` func vertexAttributeData(forAttributeNamed name: String) -> MDLVertexAttributeData? ``` ## Parameters `name` The attribute name for which to retrieve data. See Vertex Attributes for standard attribute names. ## Return Value The vertex data for the specified attribute, or `nil` if the mesh does not contain vertex data for the specified attribute. ## Discussion Calling this data is equivalent to using the mesh’s [`vertexDescriptor`](/documentation/ModelIO/MDLMesh/vertexDescriptor) object to find the index of the [`MDLMeshBuffer`](/documentation/ModelIO/MDLMeshBuffer) object corresponding to the specified vertex attribute in the mesh’s [`vertexBuffers`](/documentation/ModelIO/MDLMesh/vertexBuffers) array, then using the vertex buffer’s [`map()`](/documentation/ModelIO/MDLMeshBuffer/map()) method to gain read-only access to the vertex buffer’s data. > Important: > The buffer’s storage remains mapped for as long as the returned ``doc://com.apple.modelio/documentation/ModelIO/MDLVertexAttributeData`` object exists, potentially restricting other uses of that storage. For example, if a buffer’s storage is shared with GPU memory, that buffer may be unavailable for use in rendering until the data object is deallocated. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)