utils.js

function lerp(A, B, t){
  return A+(B-A)*t;
} // TODO: Find out what this function is typically used for
//@dev This function helps to create shapes with a specific percentage away from the given parameters

function getIntersection(A,B,C,D){
    const tTop=(D.x-C.x)*(A.y-C.y)-(D.y-C.y)*(A.x-C.x);
    const uTop=(C.y-A.y)*(A.x-B.x)-(C.x-A.x)*(A.y-B.y);
    const bottom=(D.y-C.y)*(B.x-A.x)-(D.x-C.x)*(B.y-A.y);

    if(bottom!=0){
        const t=tTop/bottom;
        const u=uTop/bottom;
        if(t>=0 && t<=1 && u>=0 && u<=1){
            return {
                x:lerp(A.x,B.x,t),
                y:lerp(A.y,B.y,t),
                offset:t
            }
        }
    }

    return null;
}

function polysIntersect(poly1, poly2){
  for (let i = 0; i < poly1.length; i++) {
    for (let j = 0; j < poly2.length; j++) {
      const touch = getIntersection(
        poly1[i],
        poly1[(i + 1) % poly1.length],
        poly2[j],
        poly2[(j + 1) % poly2.length]
      )
      if(touch){
        return true;
      }
    }
  }
  return false;
}

function getRGBA(value){
    const alpha=Math.abs(value);
    const R=value<0?0:255;
    const G=R;
    const B=value>0?0:255;
    return "rgba("+R+","+G+","+B+","+alpha+")";
}