shaderWrite

Set this option if you access the given texture with a write() function in any shader. This option enables the access::write attribute for the texture. For more information about texture functions and access attributes, see Metal Shading Language Guide.

If the texture is a read-write texture that you also access with a read() function in the same shader, set the shaderRead option to enable the access::read_write attribute.

In iOS devices with GPU family 5, Metal doesn’t apply lossless compression to the given texture if you set this option.