If I have a Ptr Foo, where Foo has a bar :: Word32 field, I can get that field's value like:
bPeekByteOff @Word32 fooPtr $ bFieldOffsetOf @"bar" (undefined :: Foo)
It would be nice to not have to explicitly specify the type of the field when getting it, as that should be determinable by the field name. It would also be nice to have a single function that covers this, like readField from Graphics.Vulkan.Marshal.