Type Definition ul_sys::ULSurfaceDefinitionLockPixelsCallback

type ULSurfaceDefinitionLockPixelsCallback = Option<unsafe extern "C" fn(user_data: *mut c_void) -> *mut c_void>;

The callback invoked when a Surface's pixel buffer is requested to be locked for reading/writing (should return a pointer to locked bytes).

@param user_data User data pointer uniquely identifying the surface.