I do this exact thing in
Cryptoglyphs for the bonus timer.
It the circle reduces in sections but resets smoothly, which would simulate what you are trying to achieve.
The way I do it is to create a single section of the circle, place it where I want it and then offset the centre of rotation to the centre of the circle. Then clone the sprite several times, rotating each one so that it creates a complete circle.
Then when you want to reduce or increase the health bar you use a tween to interpolate the rotation of ALL the sections. Each section is interpolated to rotate from its starting position to the end position. So for example, if you want to display 75% health, each section of the health bar is interpolated to rotate 75% towards it's maximum. They overlap each other, obviously, so you could only use a flat coloured image but for the most part that is what you want anyway.
The only other hurdle is at the extreme when all sections rotate beyond the scope of the "wheel". For that, I have grabbed an image of the screen and a place a sprite of it over the top of the sections of health bar which hides them perfectly.
In the videos, on the
Cryptoglyphs page you can see the bonus wheel being reduced incrementally. I will knock up a video when I get home of it smoothly resetting.
Give me a shout if you need any other info.
AGK V2 user - Tier 1 (mostly)
