Cache or optimize triangulation data used for drawing with fill operation

[obiot]

the current Path2d triangulatePath() method :

melonJS/src/geometries/path2d.js

Lines 55 to 78 in bb2c020

	triangulatePath() {
	var i = 0;
	var points = this.points;
	var vertices = this.vertices;
	var indices = earcut(points.flatMap(p => [p.x, p.y]));
	// pre-allocate vertices if necessary
	while (vertices.length < indices.length) {
	vertices.push(pool.pull("Point"));
	}
	// calculate all vertices
	for (i = 0; i < indices.length; i++ ) {
	var point = points[indices[i]];
	vertices[i].set(point.x, point.y);
	}
	// recycle overhead from a previous triangulation
	while (vertices.length > indices.length) {
	pool.push(vertices[vertices.length-1]);
	vertices.length -= 1;
	}
	return vertices;

does not cache the generated data, forcing melonJS to recalculate every thing when using directly method like fillRect() and friends, and create a huge performance bottleneck.

For reference here below is an extract from a benchmark on fill operation for both rectangle and circle:

melonJS 15.0.0 (M1 Max)	Fill (rect)	Fill (circle)
500 op/s	60 fps	60 fps
1000 op/s	60 fps	32 fps
2500 op/s	35 fps	12 fps
5000 op/s	16 fps	6 fps
10000 op/s	6 fps	4 fps
15000 op/s	4 fps	3 fps

which shows performances dropping when drawing more than 1'000 shapes per frame.