LeapShodou (LeapMotion で書道？)

import com.onformative.leap.LeapMotionP5; 

float colR=0, colG=0, colB=0; 

LeapMotionP5 leap; 

PVector fp; 

PVector pfp; 

void setup() { 

  size(800, 800); 

  leap = new LeapMotionP5(this); 

  background(191); 

  fp = leap.getTip(leap.getFinger(0)); 

  pfp=fp; 

} 

void draw() { 

  fp = leap.getTip(leap.getFinger(0)); 

  float thickness = 20 - fp.dist(pfp); 

  println("thickness="+thickness); 

  if(thickness > 0) { 

    strokeWeight(thickness); 

    stroke(colR, colG, colB); 

    line(pfp.x,pfp.y,fp.x,fp.y); 

  } 

  pfp=fp; 

} 

public void stop() { 

  leap.stop(); 

} 

void keyPressed() { 

  switch(key) { 

    case ' ': 

        background(191); 

        break; 

    case 'r': // Red 

        colR=255; colG=0; colB=0; 

        break; 

    case 'w': // White 

        colR=255; colG=255; colB=255; 

        break; 

    case 'k': // Black 

        colR=0; colG=0; colB=0; 

        break; 

  } 

}