Hi,
Fixed function drawing apis like Graphics2 are very useful (and I'm starting to do a lot of debug drawing now).
Right now, it's very basic so I would like to make changes and redesign to improve it.
A drawing api that I like a lot is p5.js and I'm aiming for something like it: https://p5js.org/reference/#group-Shape
Concept:

var g2 = framebuffer.g2;
g2.begin();

g2.fill(Color.Red);
g2.ellipse(8, 8, 128, 64);
g2.rect(30, 20, 55, 55);

g2.noFill();
g2.beginShape();
g2.vertex(30, 75);
g2.vertex(40, 20);
g2.vertex(50, 75);
g2.vertex(60, 20);
g2.vertex(70, 75);
g2.vertex(80, 20);
g2.endShape();

g2.end();

Are you interested in these changes for Kha?

Very much so.
Important points:
There is an earlier issue on changing g2, please have a look: https://github.com/KTXSoftware/Kha/issues/214
g2 is designed to efficiently map to at least <canvas>, the Java Painter api and WPF - I don't want to break that.

@Robert I'm not sure about using objects for parameters or fixed functions. Parameter objects are much more dynamic and useful in the long term but requires allocation and null checks (as an optional argument). Anyway, think parameters would be better here.
I already implement some shapes, fill, and stroke for GL rendering.
I'll take a look at the others APIs. It seems like webgl or canvas is automatically setup at start up. Can I force canvas rendering in the khafile or Kore?

I like the object parameter thing. Allocations can be avoided using inline constructors.
To force canvas set gl to null right here: https://github.com/KTXSoftware/Kha/blob/master/Backends/HTML5/kha/SystemImpl.hx#L270

@Robert Are the java and wpf targets working?
khamake generate files without error but building from Eclipse and Visual Studio 2015 don't work.
It's the same with a previous version of Kha.

WPF by default compiles to a library but worked last time I tested. Java probably needs a little fixing. Can have a look tonight.

Had a look at the Java backend - looks like that one hasn't been used in ages, will need a little more work than I can do this evening. But I'm on it.

Right.
I'll try again the wpf target.