let pal = [];

​

const HOR_ST = 64;

const VER_ST = 64;

const RES = 10;

​

let polygon = [{x:1,y:1},

               {x:10,y:10},

               {x:1,y:19}

              ]

​

function setup() {

  createCanvas(640, 600);

  stroke(255);

  pal.push(PALETTE[floor(random(PALETTE.length))],PALETTE[floor(random(PALETTE.length))])

}

​

function draw() {

  background(255);

  polygon[1] = {

    x:mouseX/RES,

    y:mouseY/RES

  }

  for(let y=0;y<VER_ST;y++){

    let drawing = 0;

    fill(pal[drawing]);

    // do a scanline

    let scy=y+0.5;

    let scx=[];

    for(let i=0;i<polygon.length;i++){

      //line segment is: plgn[i]>plgn[(i+1)%length]

      let p1=polygon[i];

      let p2=polygon[(i+1)%polygon.length]

      if( (scy-p1.y) * (scy-p2.y) > 0 ){ continue; } //check if they intersect at all

      scx.push( p1.x + (p2.x-p1.x) * ((scy-p1.y)/(p2.y-p1.y)) );

    }

    scx.sort(function (a, b) { return a-b; }); //this function return shit stops it from sorting alphabetically but idk why

    for(let x=0;x<HOR_ST;x++){

      //check for intersections

      if(x+0.5 >= scx[0]){

        drawing = 1 - drawing;

        fill(pal[drawing]);

        scx.shift();

      }

      // fill(pal[round(noise(x*0.1,y))]); // cute noise

      drawStitch(x,y);

    }

  }

}

​

function drawStitch(x,y){

  beginShape();

  vertex((x+0.0)*RES,(y+0.0)*RES);

  vertex((x+0.0)*RES,(y+1.0)*RES);

  vertex((x+0.5)*RES,(y+1.5)*RES);

  vertex((x+0.5)*RES,(y+0.5)*RES);

  endShape(CLOSE);

  beginShape();

  vertex((x+1.0)*RES,(y+0.0)*RES);

  vertex((x+0.5)*RES,(y+0.5)*RES);

  vertex((x+0.5)*RES,(y+1.5)*RES);

  vertex((x+1.0)*RES,(y+1.0)*RES);

  endShape(CLOSE);

}