# setFragmentBuffer(_:offset:index:) Assigns a buffer to an entry in the fragment shader argument table. ``` func setFragmentBuffer(_ buffer: (any MTLBuffer)?, offset: Int, index: Int) ``` ## Parameters `buffer` An [`MTLBuffer`](/documentation/Metal/MTLBuffer) instance the command assigns to an entry in the fragment shader argument table for buffers. `offset` An integer that represents the location, in bytes, from the start of `buffer` where the fragment shader argument data begins. See the [Metal feature set tables (PDF)](https://developer.apple.com/metal/Metal-Feature-Set-Tables.pdf) to check for offset alignment requirements for buffers in `device` and `constant` address space. `index` An integer that represents the entry in the fragment shader argument table for buffers that stores a record of `buffer` and `offset`. ## Discussion By default, the buffer at each index is `nil`. --- 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)