What is UnsafeMutablePointer? How to modify the underlying memory?

Question

I am trying to work with SpriteKit\'s SKMutableTexture class but I don\'t know how to work with UnsafeMutablePointer< Void >. I have a vague idea that it

Answer 1

UnsafeMutablePointer is the Swift equivalent of void* - a pointer to anything at all. You can access the underlying memory as its memory property. Typically, if you know what the underlying type is, you'll coerce to a pointer to that type first. You can then use subscripting to reach a particular "slot" in memory.

For example, if the data is really a sequence of UInt8 values, you could say:

let buffer = UnsafeMutablePointer(ptr)

You can now access the individual UIInt8 values as buffer[0], buffer[1], and so forth.