w3_04v5

/*

 * Creative Coding

 * Week 3, 04 - spinning top: curved motion with sin() and cos()

 * by Indae Hwang and Jon McCormack

 * Copyright (c) 2014 Monash University

 *

 * This sketch is the first cut at translating the motion of a spinning top

 * to trace a drawing path. This sketch traces a path using sin() and cos()

 *

 */

​

float[] x;

float[]y;      // current drawing position

float []dx;

float[] dy;    // change in position at each frame

float rad;       // radius for the moving hand

int num;        // number of spinners

​

void setup() {

  size(500, 500);

colorMode(HSB, 360, 100,100);

  num = 2;

  x = new float[num];

  y = new float[num];

  dx = new float[num];

  dy = new float[num];

  // initial position in the centre of the screen

  for(int i=0; i<num; i++){

  x[i] = (250 - i*random(-10,10));

  y[i] = (250 + i*random(-10,10));

​

  // dx and dy are the small change in position each frame

  dx[i] = random(-1, 1);

  dy[i] = random(-1, 1);

  }

  background(125);

}

​

void draw() {

  strokeWeight(2);

  stroke(#A75265, 120);

  fill (h, 23, 90);

  ellipse(x, y, 60, 60);

  h = h + random(3);

  if (h > 360)  {

  h = 0;

  }

for (int i=0; i<num; i++){

rad = radians(frameCount);

​

​

​

  // calculate new position

  x[i] += dx[i];

  y[i] += dy[i];

​

  float max = 1;

  float min = 0.5;

​

  //When the shape hits the edge of the window, it reverses its direction and changes velocity

  if (x[i] > width-100 || x[i] < 100) {

    dx[i] = dx[i] > 0 ? -random(min, max) : random(min, max);

  }

​

  if (y[i] > height-100 || y[i] < 100) {

    dy[i] = dy[i] > 0 ? -random(min, max) : random(min, max);

  }

​

  float bx = x[i] + 100 * sin(rad);

  float by = y[i] + 100 * cos(rad);

​

  noFill();

​

  float radius = 100 * sin(rad*0.1);

  float handX = bx + radius * sin(rad*3);

  float handY = by + radius * cos(rad*3);

  float howLong = (dist(bx, by, handX, handY)+i*10);

  float h = map(howLong, 0, 100, 0, 360);

  stroke(h, 99, 99, 99);

  arc(bx, by, handX/(num*i), handY/(num*i),PI, PI+HALF_PI);

​

}

}

​