Tell me if this will work:

Ok so for the game i am making i have a sprite class, within the class i have the two bitmaps. The first bitmap is just the legs of my sprite guy and the second bitmap is the upper body of my sprite guy, both bitmaps are the same size and have the same position. I set it up like this becouse i just want the upper body of my guy to rotate so i had to make the center of that bitmap at the waist. now i am thinking that i will first draw the first bitmap then rotate the DC with SetWorldTransform, tell me if this is the right thing to use, and draw the second bitmap with the same coordinates. Can i use the same corrdinates as i would normally with a not rotated DC? The amount of rotation will be determined by the last mouse position with the current one, so i can tell if they moved the mouse up or down and subtract or add to the angle accordingly. can some one also tell me what the best sin and cos functions will work for this the best. This is all Win32Api.

Sorry if this question seems very spread out and sloppy but thanks for any replies.