Cocoa listen for mouse move events when the mouse moves, not the cursor

Question

I'm developing a game in Cocoa, and I want to rotate the camera when the user moves the mouse, and the screen is limiting the camera movement. I hid the mouse cursor, but I want to listen when the physical mouse moves, not when the mouse cursor moves. I've heard about IOKit but that seems to be too low level. If it is any high-level way to do that, then how? And else, how do I use IOKit.

Ken Thomases Ken Thomases · Accepted Answer · 2017-05-03T16:16:13

When you hide the cursor, call CGAssociateMouseAndMouseCursorPosition(FALSE). That will make it so that mouse movement does not move the cursor.

You will continue to get NSEventTypeMouseMoved, NSEventTypeLeftMouseDragged, NSEventTypeRightMouseDragged, and NSEventTypeOtherMouseDragged events as the mouse is moved (depending on whether buttons are pressed during the move). Because the cursor isn't moving, the locationInWindow won't be meaningful. It will continue to report the last location from when you disassociated the cursor from the mouse. However, the deltaX and deltaY properties will indicate how far and in what direction the mouse moved.

Cocoa listen for mouse move events when the mouse moves, not the cursor

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