# useResource(_:usage:) Ensures kernel calls that the system encodes in subsequent commands have access to a resource. ``` func useResource(_ resource: any MTLResource, usage: MTLResourceUsage) ``` ## Parameters `resource` An [`MTLResource`](/documentation/Metal/MTLResource) instance used in an argument buffer. `usage` How the compute pass can access data, including [`read`](/documentation/Metal/MTLResourceUsage/read) and [`write`](/documentation/Metal/MTLResourceUsage/write) permission. For applicable resources, you may be able to prevent the GPU from unnecessarily decompressing color attachments on some devices by setting `usage` to [`read`](/documentation/Metal/MTLResourceUsage/read) . ## Discussion You can make a resource *resident* (available in GPU memory) for the remaining duration of the compute pass by calling this method. Call the method before encoding function calls that may access the `resource` through an argument buffer. The method ensures the resource is in a format that’s compatible with the kernels that depend on it. > Note: > You don’t need to call this method if you bind a resource for compute kernels to access. The method also informs Metal when to apply hazard tracking for a resource you create with [`MTLHazardTrackingMode.tracked`](/documentation/Metal/MTLHazardTrackingMode/tracked). For a resource you create with [`MTLHazardTrackingMode.untracked`](/documentation/Metal/MTLHazardTrackingMode/untracked), you need to apply an [`MTLFence`](/documentation/Metal/MTLFence) or an [`MTLEvent`](/documentation/Metal/MTLEvent) to account for potential reading and writing hazards. You can reconfigure an individual resource’s `usage` options for subsequent draw calls in the same render pass by calling this method again. Apps typically call this method for a resource in an argument buffer as a part of their *bindless* implementation. For more information about argument buffers and bindless implementations, see [Improving CPU performance by using argument buffers](/documentation/Metal/improving-cpu-performance-by-using-argument-buffers) and [Go bindless with Metal 3](https://developer.apple.com/videos/play/wwdc2022/10101/), respectively. --- 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)