JS30 Challenge Day 8 - Fun with Canvas

Github Link

Most of the terms used in this program are canvas specific. I am leaving those terms to the video itself. 

A nice way to set an implicit function

()=>{}

Example:

canvas.addEventListener('mousedown', ()=>isDrawing=true);

An ES6 way to define multiple variables in one statement

 [lastX, lastY] = [e.offsetX, e.offsetY];