So, this took a lot of time to make, and lots of algebra and trig, and there are still a few glitches, but here it is! This only lets you drag along the x-axis, and keeps the y-axis the same, but calculates the relative x and relative y of the object. in 2-D, it isn't that exciting, but this could be transferred into 3-D, with the camera pointing from the bottom up forwards, and it is a birds-eye view. the mouse would only be able to drag along the x and z axis of the screen.