笑脸效果图：

processing代码：

void setup(){
  size(1000,1000);//Canvas size
  background(#ffcc33);//Canvas background color
}
void draw(){
strokeWeight(12);//face-width12px
fill(#ffffcc);//face
arc(500,500,200,200,0,TWO_PI);//face-size
strokeWeight(4);
noFill();//eyebrow-l
arc(450,480,50,50,PI,TWO_PI);
noFill();//eyebrow-r
arc(550,480,50,50,PI,TWO_PI);
strokeWeight(2);
fill(#ff9999);//mouth
arc(500,525,80,80,0,PI);
strokeWeight(6);
fill(0);
line(500,500,500,480);
strokeWeight(10);//nose
point(498,502);//nose-l
point(502,502);//nose-r
}