Drawing Non-overlapping Circles

https://www.dwitter.net/d/15017

Javascript...

with(x)t?onmousedown=onmousemove=e=>{beginPath(Z=99*e.buttons),arc(X=e.x,Y=e.y,(A.map(a=>Z=(R=((a.X-X)**2+(a.Y-Y)**2)**.5)>a.Z+Z?Z:R-a.Z),Z),0,7);Z>0&&A.push({X,Y,Z}),fill()}:(c.width=568,A=[]);