instance mode

[pietroppeter]

with nim macros it could be actually much more painless than in p5js to support instance mode: https://github.com/processing/p5.js/wiki/Global-and-instance-mode

instead of:

const s = ( sketch ) => {

  let x = 100;
  let y = 100;

  sketch.setup = () => {
    sketch.createCanvas(200, 200);
  };

  sketch.draw = () => {
    sketch.background(0);
    sketch.fill(255);
    sketch.rect(x,y,50,50);
  };
};

let myp5 = new p5(s, 'p5sketch1');

we could have:

newP5Instance("p5sketch1"):
  let
    x = 100
    y = 100

  setup:
    createCanvas(200, 200)

  draw:
    background(0)
    fill(255)
    rect(x, y, 50, 50)

and the difference between global and instance mode would just be a macro away (instead of having to add manually sketch.).

and we could actually have in nimib a nbP5Instance which automatically provides a new id and an html container for the sketch in order to have multiple sketches on the same page.

note that I would not know at the moment where to start to build that macro and in particular on how to generate all the closure js syntax (my fallback would be: use emit...).

[pietroppeter]

implemented in #5