Draw rects inside Konva layer bound by a region with uniform distribution - konvajs

Question

I am using Konva.js to render some colourful boxes.
I have a Stage with some set size and regions within that Stage, bound by points (e.g. rectangles, but they can be any polygons).
I then need to add some number of smaller rects inside this area such that they look nice and are uniformly distributed.
E.g.
// these numbers are an example only, irrelevant
let width = 500 * 1.936402653140851;
let height = 500;
// setup stage, boilerplate
var stage = new Konva.Stage({
container: 'container',
width: width,
height: height
});
// region layer - boundaries
var regionLayer = new Konva.Layer({
scale: {x: width/4963, y: height/2563} // these numbers are an example only, irrelevant
});
stage.add(regionLayer);
// for this example, a single region, L-shaped on it's side
let box = new Konva.Line({
name: 'region-1',
points: [1067, 681,
3337, 681,
3337, 987,
3037, 987,
3037, 787,
1067, 787],
closed: true,
fill: 'blue',
opacity: 0.5
});
regionLayer.add(box);
regionLayer.draw();
// layer to draw rects in
let rectsLayer = new Konva.Layer({
scale: {x: width/4963, y: height/2563} // these numbers are an example only, irrelevant
});
for (let i = 0; i < 90; i++) { // e.g. some number up to X
let rect = new Konva.Rect({
width: 20,
height: 20,
fill: 'red',
x: 1067 + 40 * (i + 1),
y: 681 + 20
});
rectsLayer.add(rect);
}
stage.add(rectsLayer);
rectsLayer.draw();
The result of the above is something like this
What I'd like to have, is those boxes filling free area within the boundaries of my polygon only.
I read a whole heap about Delauney triangulation, Voronoi diagrams and sequencing for normal distribution to make it happen, but sadly I came up with zilch on practical approach of doing this.
https://jsfiddle.net/x4aksz1y/2/