textureLoad and/or textureSampleBaseClampToEdge are required to support external textures textureSampleBaseClampToEdge - https://www.w3.org/TR/WGSL/#textureSampleBaseClampToEdge => already takes a sampler so the assumption is the user has defined one in their WGSL textureLoad(texture, pixelCoords, levelOfDetail) - https://www.w3.org/TR/WGSL/#textureload => does not take a sampler, one can use read on the 2d texture, e.g., in MSL texture.read(pixelCoords, levelOfDetail)