10. November 2010

I edited the patch by adding a start click without starting the animation -not before clicking the end point.

PVector     startPos = new PVector();
PVector     endPos = new PVector();
int         curTime = 0;
int         animSpeed = 5;
int         animTime = 2000;
boolean     drawFlag=false;
boolean     flagDir=true;    //direction
boolean     pressedOnce=false;

void setup()
{
  size(640, 480);
  smooth();
}

void draw() {
  curTime += animSpeed;
  background(51);
  // calc. the animation time

  //VARIANTE 1
  /*if(curTime== animTime)
   flagDir=false;
   else if(curTime== 0)
   flagDir=true;
   
   if(!flagDir)
   curTime -= animSpeed;
   else
   curTime += animSpeed;*/

  //VARIANTE 2
  if(curTime==animTime || curTime==0)
    animSpeed*=-1;

  // calc. the current time in the animation
  float normTime = curTime * 1.0 / animTime;  //prozentzahl von 0..1 ;

  if(drawFlag)
  {
    stroke(255);
    line(startPos.x,startPos.y, endPos.x,endPos.y);


    // calculate the position of the circle on the line
    PVector dir = PVector.sub(endPos,startPos);

    PVector pos = PVector.add( startPos, PVector.mult(dir,normTime));
    ellipse(pos.x,pos.y, 20,20);
  }
}

void mousePressed()
{
  if(pressedOnce) {
    endPos.set(mouseX,mouseY,0);   
    curTime = 0;
    drawFlag=true;
    pressedOnce=false;
  }
  else {
    startPos.set(mouseX,mouseY,0);
    pressedOnce=true;
    drawFlag=false;
  }
}

void mouseDragged()
{
}

void mouseReleased()
{
  println("pressedOnce: " +pressedOnce +" | " + "drawFlag: "+drawFlag);
}