Triangle.Using p5.js library.
function setup() {
createCanvas(720, 400);
}
function draw() {
background(0, random(128, 255), random(128, 255));
noStroke(0);
for (var i = 0; i < 20; i++) {
// triangle a
var x1 = random(0, 360);
var y1 = random(0, 200);
var x2 = random(360, 720);
var y2 = random(200, 400);
var x3 = random(0, 360);
var y3 = random(0, 200);
// triangle b
var x4 = random(360, 720);
var y4 = random(0, 200);
var x5 = random(0, 360);
var y5 = random(200, 400);
var x6 = random(360, 720);
var y6 = random(0, 200);
fill(random(0, 128), random(128, 255), random(0, 128), random(50, 150));
triangle(x1, y1, x2, y2, x3, y3);
triangle(x4, y4, x5, y5, x6, y6);
}
frameRate(1);
}