Functions to create primitives and other shapes

[sainsaji]

It would be nice to have some functions that would create:

• ellipses
• rounded rectangles
• curves
• triangles
• Arcs

At least circles and triangles

[matsuura-h]

I added 6 functions (ellipse / filled ellipse / circle / filled circle / triangle / filled triange) to this library. But these functions are based on BSD License code, LovyanGFX. I didn't know how to handle the two licenses, MIT and BSD, so I created a fork. Please try it if you like. https://github.com/matsuura-h/gc9a01py/tree/main

I would also be happy if you could tell me how to handle licenses.