Lesson 4.1 – Basic Leap Examples

Using Gestures:

import de.voidplus.leapmotion.*;

LeapMotion leap;


void setup(){
    size(800, 500);
    background(255);
    // leap = new LeapMotion(this).withGestures(); // with all gestures
     leap = new LeapMotion(this).withGestures("swipe"); // Leap detects only swipe gestures.
}

void draw(){
}

// ----- SWIPE GESTURE -----

void leapOnSwipeGesture(SwipeGesture g, int state){
  
          int  id                  = g.getId();
          PVector position_start      = g.getStartPosition();
          PVector position            = g.getPosition();

    switch(state){
        case 1: // Start
            break;
        case 2: // Update
            break;
        case 3: // Stop
            position.sub(position_start);
            position.normalize();
            if(position.x >= 0) {
               println("towards right");
            } else {
              println("towards left");
            }
             break;
        }
}

Finding hand positions:

import de.voidplus.leapmotion.*;

LeapMotion leap;

void setup(){
  size(1000, 800);
  leap = new LeapMotion(this);
}

void draw(){
  background(255);


  // ========= get hand locations from Leapmotion =========
  for(Hand hand : leap.getHands()){

    // ----- Variables -----
    PVector hand_position    = hand.getPosition();
    boolean hand_is_left     = hand.isLeft();
    boolean hand_is_right    = hand.isRight();
    
   if(hand_is_left) {
         // println("left"+hand_position);
          fill(0,0,255);
          ellipse(hand_position.x, hand_position.y, 16, 16);
    } 
  if(hand_is_right) {
        fill(255,0,0);
          //println("right"+hand_position);
          ellipse(hand_position.x, hand_position.y, 16, 16);
    } 
   }
}