This is a representation of a heartline roll. Most comonly found on roller-coasters some popular rides like Steel Vengeance and Cheetah Hunt use the heartline roll. A heartline roll is a inversion that spins a object in a 360 roll while changing the evevation to keep the object on the heartline. Fun Fact, did you know that heartline rolls are sometimes called 0-g-roll becasue you will experince 0 g-force in the roll? The black line here is the heartline.
Very simple code, but efective. Anyone can use my sprite as long as they give me, BCD1313 credit.