// 20.03.2004 nick

color COL_Background, COL_Shape;
float globalAngle = 0.0f;
void setup()
{
  size(400,400);
  ellipseMode(CENTER_RADIUS);
  noStroke();
  COL_Background = color(204,0,102);
  COL_Shape = color(0,51,0);

}

void loop()
{
  globalAngle+=0.01f;
  background(COL_Background);

  int sides = 2+mouseX/50;
  float scaler = 1.0f - (((mouseY-(height/2))/(float)height)*2.0f);
  float radius = 100 + ((float)sides * 5.0f);
  drawShape(200,200,radius,sides, globalAngle, scaler, COL_Shape);

}

void drawShape(float x, float y, float radius, int sides, float angle, float scaler, color col)
{

  float segmentAngle = TWO_PI / (float)sides;
  float ox=0,oy=0,oox,ooy,d,mpx,mpy;

  // draw inner poly
  fill(col);
  beginShape(POLYGON);
  for (int i=0;i<sides+1;i++)
  {
    ox = sin((float)i*segmentAngle+angle)*radius;
    oy = cos((float)i*segmentAngle+angle)*radius;
    vertex(x+ox,y+oy);
  }
  endShape();

  for (int i=0;i<sides+1;i++)
  {
    oox=ox;
    ooy=oy;
    ox = sin((float)i*segmentAngle+angle)*radius;
    oy = cos((float)i*segmentAngle+angle)*radius;
    if (i==0) continue;
    d = sqrt(sq(oox-ox)+sq(ooy-oy));
    mpx=(oox+ox)/2;
    mpy=(ooy+oy)/2;
    fill(col);
    ellipse(x+ox,y+oy,(d/4)*scaler,(d/4)*scaler);
    fill(COL_Background);
    ellipse(x+mpx,y+mpy,(d/4)*(2.0f-scaler),(d/4)*(2.0f-scaler));
    fill(200);
    ellipse(x+mpx,y+mpy,(d/4)*(2.0f-scaler)*0.5f,(d/4)*(2.0f-scaler)*0.5f);
  }

  for (int i=0;i<sides+1;i++)
  {
    oox=ox;
    ooy=oy;
    ox = sin((float)i*segmentAngle+angle)*radius;
    oy = cos((float)i*segmentAngle+angle)*radius;
    if (i==0) continue;
    d = sqrt(sq(oox-ox)+sq(ooy-oy));
    mpx=(oox+ox)/2;
    mpy=(ooy+oy)/2;
    fill(200);
    ellipse(x+mpx,y+mpy,(d/4)*(2.0f-scaler)*0.5f,(d/4)*(2.0f-scaler)*0.5f);
  }
}