JSFiddle - React, Tailwind, and code Playground
HTML
<canvas id="myc" height="400" width="400"></canvas>
JavaScript
var c=document.getElementById("myc");
var ctx = c.getContext("2d");
ctx.scale(4, 4)
var theta = 1.5; // angle that will be increased each loop
var outertheta = 1.4;
var step = 2*Math.PI/20; // amount to add to theta each time (degrees)
var r = 10;
var outerR = r+6;
var points = [];
for (i = theta; i <= 2*Math.PI; i += step) {
x = 30 + r * Math.cos(i);
y = 30+ r * Math.sin(i);
ctx.fillRect(x,y,1,1);
points.push([x,y]);
debugger;
}
for (i = 2*Math.PI; i >= outertheta; i -= step) {
x = 30 + (outerR) * Math.cos(i);
y = 30+ (outerR) * Math.sin(i);
ctx.fillRect(x,y,1,1);
points.push([x,y]);
debugger;
}
console.log(points);