# Adding mipmap filtering to samplers Specify how the GPU samples mipmaps in your textures. ## Discussion By default, samplers sample data only from mipmap `0`. If your texture contains more than one mipmap, and you want it to sample the lower-level mipmaps, you need to specify this behavior when you create the texture sampler. ### Create the sampler in your app If you’re creating an [`MTLSamplerState`](/documentation/Metal/MTLSamplerState) instance, create the [`MTLSamplerDescriptor`](/documentation/Metal/MTLSamplerDescriptor) instance and set its [`mipFilter`](/documentation/Metal/MTLSamplerDescriptor/mipFilter) property. The following code uses linear filtering for the minification and magnification filter, and uses linear filtering for mipmaps. This combination is usually called *trilinear filtering*. With this configuration, the GPU chooses the two mipmaps nearest in size and generates a sample by linearly filtering four pixels from each mipmap. Then it blends those two values with a linear interpolation to generate the final sample. ```swift let descriptor = MTLSamplerDescriptor() descriptor.minFilter = MTLSamplerMinMagFilter.linear descriptor.magFilter = MTLSamplerMinMagFilter.linear descriptor.mipFilter = MTLSamplerMipFilter.linear let sampler = device.makeSamplerState(descriptor: descriptor) ``` Alternatively, any of these filters could filter from the nearest pixel, instead of a linear filter, resulting in fewer sampled pixels but lower quality. Ultimately, you need to decide the right tradeoffs between sampling performance and quality for your app. ### Create the sampler in your shader If you prefer to create samplers in your shader, specify the mipmap filtering there instead of in your app: ```metal constexpr sampler s(filter::linear, mip_filter::linear) ``` --- 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)