topical media & game development

topical media & game development
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _
#javascript-processing-example-topic-motion-puff.htm / htm

  <!DOCTYPE html>
  <html><head>
  <script src="javascript-processing-example-processing.js"></script>
  <script src="javascript-processing-example-init.js"></script>
  <link rel="stylesheet" href="javascript-processing-example-style.css">
  </head><body><h1><a href="http://ejohn.org/blog/processingjs/">Processing.js</a></h1>
  <h2>Puff</h2>
  
  <p>by Ira Greenberg.  
  
  Series of ellipses simulating a multi-segmented 
  organism, utilizing a follow the leader algorithm.
  Collision detection occurs on the organism's head, 
  controlling overall direction, and on the individual 
  body segments, controlling body shape and jitter.</p>
  
  <p><a href="http://processing.org/learning/topics/puff.html"><b>Original Processing.org Example:</b> Puff</a><br>
  <script type="application/processing">
  // for puff head
  float headX;
  float headY;
  float speedX = .7;
  float speedY = .9;
  
  // for puff body
  int cells = 1000;
  float[]px= new float[cells];
  float[]py= new float[cells];
  float[]radiiX = new float[cells];
  float[]radiiY = new float[cells];
  float[]angle = new float[cells];
  float[]frequency = new float[cells];
  float[]cellRadius = new float[cells];
  
  void setup(){
    
    size(200, 200);
    // begin in the center
    headX = width/2;
    headY = height/2;
  
    //fill body arrays
    for (int i=0; i< cells; i++){
      radiiX[i] = random(-7, 7); 
      radiiY[i] = random(-4, 4);
      frequency[i]= random(-9, 9);
      cellRadius[i] = random(16, 30);
    }
    frameRate(30);
  }
  
  void draw(){
    background(0);
    noStroke();
    fill(255, 255, 255, 5);
  
    //follow the leader
    for (int i =0; i< cells; i++){
      if (i==0){
        px[i] = headX+sin(radians(angle[i]))*radiiX[i];
        py[i] = headY+cos(radians(angle[i]))*radiiY[i];
      } 
      else{
        px[i] = px[i-1]+cos(radians(angle[i]))*radiiX[i];
        py[i] = py[i-1]+sin(radians(angle[i]))*radiiY[i];
  
        //check collision of body
        if (px[i] >= width-cellRadius[i]/2 || px[i] <= cellRadius[i]/2){
          radiiX[i]*=-1;
          cellRadius[i] = random(1, 40);
          frequency[i]= random(-13, 13);
        }
        if (py[i] >= height-cellRadius[i]/2 || py[i] <= cellRadius[i]/2){
          radiiY[i]*=-1;
          cellRadius[i] = random(1, 40);
          frequency[i]= random(-9, 9);
        }
      }
      // draw puff
      ellipse(px[i],  py[i],  cellRadius[i],  cellRadius[i]);
      // set speed of body
      angle[i]+=frequency[i];
    }
  
    // set velocity of head
    headX+=speedX;
    headY+=speedY;
  
    //check boundary collision of head
    if (headX >= width-cellRadius[0]/2 || headX <=cellRadius[0]/2){
      speedX*=-1;
    }
    if (headY >= height-cellRadius[0]/2 || headY <= cellRadius[0]/2){
      speedY*=-1;
    }
  }
  </script><canvas width="200" height="200"></canvas></p>
  <div style="overflow: hidden; height: 0px; width: 0px;"></div>
  
  <pre><b>// All Examples Written by <a href="http://reas.com/">Casey Reas</a> and <a href="http://benfry.com/">Ben Fry</a>
  // unless otherwise stated.</b>
  // for puff head
  float headX;
  float headY;
  float speedX = .7;
  float speedY = .9;
  
  // for puff body
  int cells = 1000;
  float[]px= new float[cells];
  float[]py= new float[cells];
  float[]radiiX = new float[cells];
  float[]radiiY = new float[cells];
  float[]angle = new float[cells];
  float[]frequency = new float[cells];
  float[]cellRadius = new float[cells];
  
  void setup(){
    
    size(200, 200);
    // begin in the center
    headX = width/2;
    headY = height/2;
  
    //fill body arrays
    for (int i=0; i&lt; cells; i++){
      radiiX[i] = random(-7, 7); 
      radiiY[i] = random(-4, 4);
      frequency[i]= random(-9, 9);
      cellRadius[i] = random(16, 30);
    }
    frameRate(30);
  }
  
  void draw(){
    background(0);
    noStroke();
    fill(255, 255, 255, 5);
  
    //follow the leader
    for (int i =0; i&lt; cells; i++){
      if (i==0){
        px[i] = headX+sin(radians(angle[i]))*radiiX[i];
        py[i] = headY+cos(radians(angle[i]))*radiiY[i];
      } 
      else{
        px[i] = px[i-1]+cos(radians(angle[i]))*radiiX[i];
        py[i] = py[i-1]+sin(radians(angle[i]))*radiiY[i];
  
        //check collision of body
        if (px[i] &gt;= width-cellRadius[i]/2 || px[i] &lt;= cellRadius[i]/2){
          radiiX[i]*=-1;
          cellRadius[i] = random(1, 40);
          frequency[i]= random(-13, 13);
        }
        if (py[i] &gt;= height-cellRadius[i]/2 || py[i] &lt;= cellRadius[i]/2){
          radiiY[i]*=-1;
          cellRadius[i] = random(1, 40);
          frequency[i]= random(-9, 9);
        }
      }
      // draw puff
      ellipse(px[i],  py[i],  cellRadius[i],  cellRadius[i]);
      // set speed of body
      angle[i]+=frequency[i];
    }
  
    // set velocity of head
    headX+=speedX;
    headY+=speedY;
  
    //check boundary collision of head
    if (headX &gt;= width-cellRadius[0]/2 || headX &lt;=cellRadius[0]/2){
      speedX*=-1;
    }
    if (headY &gt;= height-cellRadius[0]/2 || headY &lt;= cellRadius[0]/2){
      speedY*=-1;
    }
  }</pre>
  </body></html>
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _
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