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) _

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graphic-processing-site-examples-Topics-Interaction-Reach1-Reach1.pde / pde
Reach 1. Based on code from Keith Peters (www.bit-101.com) The arm follows the position of the mouse by calculating the angles with atan2(). 

  
  
   
  float x = 100;
  float y = 100;
  float x2 = 100;
  float y2 = 100;
  float segLength = 30;
  
  void setup() {
    size(200, 200);
    smooth(); 
    strokeWeight(20.0);
    stroke(0, 100);
  }
  
  void draw() {
    background(226);
    
    float dx = mouseX - x;
    float dy = mouseY - y;
    float angle1 = atan2(dy, dx);  
    
    float tx = mouseX - cos(angle1) * segLength;
    float ty = mouseY - sin(angle1) * segLength;
    dx = tx - x2;
    dy = ty - y2;
    float angle2 = atan2(dy, dx);  
    x = x2 + cos(angle2) * segLength;
    y = y2 + sin(angle2) * segLength;
    
    segment(x, y, angle1); 
    segment(x2, y2, angle2); 
  }
  
  void segment(float x, float y, float a) {
    pushMatrix();
    translate(x, y);
    rotate(a);
    line(0, 0, segLength, 0);
    popMatrix();
  }
[] 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) _

(C) Æliens 20/2/2008

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