Click the green flag! Adjust the 'Time Multiplier' slider to alter the flow of time. You'll see an osu! slider animation. I put a lot of effort into copying all the visual effects as closely as possible and I think I did a pretty good job. This project can load any slider and display it. It also supports red anchor points. All the slider's data in inside the lists 'SliderData' and 'curvePoints'. If you changed any coordinates you have to run 'Load Bezier Slider Body' after. This code could be used for an osu! client clone in scratch. My algoritm might not be very efficient because my knowledge of bézier curves is limited, so feel free to improve it!
Bézier curves: https://en.wikipedia.org/wiki/B%C3%A9zier_curve Osu!: https://osu.ppy.sh/ Update 4-2-18: Changed the slider and added the 'Time Multiplier' option.