what is the difference between

int xoff, yoff;

get_mouse_mickeys(&xoff, &yoff);

and

int oldx, oldy;
int xoff, yoff;
xoff = (mouse_x - oldx);
yoff = (mouse_y - oldy);
oldx = mouse_x;
oldy = mouse_y;

i ask cause the second way works how i want/expect but the mouse mickeys dont work how i want/expect.

Try putting a position_mouse(SCREEN_W/2, SCREEN_H/2) in there and you'll see a big difference. Or try moving the mouse past edge of the screen.

And how do you expect them to work?

And for God's sake, use some capitalization. The shift key on your keyboard isn't just decorative.

I'm using it to rotate a camera in a OpenGL program.

The second way the camera rotates fine, but the first way, the camera will move a few degrees then go back to where it started.

EDIT:: nvm I found the error was in another part of my code. And that the two above work the same.

They don't work the same cross platform. Not all platforms allow mose events once the mouse leaves the window (or hits the edge of the screen) - in which case mouse_x/y will no longer be updated but get_mouse_mickeys() will do something clever to fake continuous mouse movement.

I cant seem to keep the mouse inside the screen on osx. Regardless of where I put position_mouse(320,240)( before or after get_mouse_mickeys ), the x,y output from get_mouse_mickeys is always 0. Any ideas? Allegro 4.2.1.