Arc Algorithm based on Bresenham Circle routine

[MaBecker]

This coding looks very promising to me, What do you think @gfwilliams ?

source: https://www.scattergood.io/arc-drawing-algorithm/
formated and copied to https://gist.github.com/MaBecker/071ca5440565dc9163a8e35a0cf2c5fc

[gfwilliams]

Thanks - what's the use case for this out of interest?

My concern is that if it goes in, it will only be able to be for some boards - some of them like the original Espruino that are too tight on flash storage will have to leave it out.

... And we do already have drawEllipse: https://github.com/espruino/Espruino/blob/master/libs/graphics/graphics.c#L532

I think it got mentioned in a post on the forum, but if difference between start and end angles is less than 180 degrees it should be possible to implement it just using drawEllipse (which I believe uses the same algorithm) and then just setting the clipRect, which feels like it would only add 100 bytes max and could probably be kept in for all boards...

[MaBecker]

there is no use case at the moment. Was interested in how to draw arcs and because of this post: https://forum.espruino.com/comments/16966259/
I will work on this and let you know about the size. A js version that use poly would be nice too. Will talk to @muet (allobjects) about this. If I remember correctly he has a js version of gauges which is not part of the ui at the moment.