MTLReadWriteTextureTier means

Hi, I'd like to know what is MTLReadWriteTextureTiermeans and how to use it. but I didn't find any documentation related to it. So I think that it's necessary for validation of Pixelformat but I don't make sure.

Additionally, I'm puzzled about Metal-Feature-Set-Tables. It is written that MTLGPUFamilyApple1 doesn't support Depth-16 pixel format in Feature Availability of Metal-Feature-Set-Tables. but in Pixel Format Capabilities, It is written that MTLGPUFamilyApple1 can use MSAA operation in Depth16Unorm. If so, does it really supports Depth-16 pixel format? These confusions make it difficult to handle format validation.


Thanks.