BlendBounceClock

Clock.pde

color[] colors = new color[4];
PVector[] vertices = new PVector[4];


int colorIndexOffset = 0;

long lastTime = 0;

void setup()
{
  size(800, 800, P3D);

  colors[0] = color(0, 255, 0);
  colors[1] = color(255, 255, 0);
  colors[2] = color(255, 0, 0);
  colors[3] = color(0, 0, 255);

  vertices[0] = new PVector(0, 0, 0);
  vertices[1] = new PVector(width, 0, 0);
  vertices[2] = new PVector(width, height, 0);
  vertices[3] = new PVector(0, height, 0);
}


void draw()
{
  long inc = 1000;

  long thisTime = millis() % inc;

  if (thisTime < lastTime)
  {
    colorIndexOffset = (colorIndexOffset + 1) % 4;
  }

  lastTime = thisTime;

  background(255);
  pushMatrix();

  noStroke();
  beginShape(QUADS);
  for (int i = 0; i < 4; ++i)
  {
    color fromColor = colors[(colorIndexOffset + i) % 4];
    color toColor = colors[(colorIndexOffset + 1 + i) % 4];
    float amount = tween(thisTime, 0.0, inc, 0.0, 1.0);

    color c = lerpColor(fromColor, toColor, amount);
    fill(c);

    vertex(vertices[i].x, vertices[i].y, vertices[i].z);
  }
  endShape();
  popMatrix();
}


float tween(float value, float inputMin, float inputMax, float outputMin, float outputMax)
{
  float t = value - inputMin;
  float c = outputMax - outputMin;
  float d = inputMax - inputMin;
  float b = outputMin;

  return easeOut(t, b, c, d);
}


float elasticEaseInOut(float t, float b, float c, float d) {
  if (t==0) return b;  
  if ((t/=d/2)==2) return b+c;
  float p=d*(.3f*1.5f);
  float a=c;
  float s=p/4;

  if (t < 1) {
    float postFix =a*pow(2, 10*(t-=1)); // postIncrement is evil
    return -.5f*(postFix* sin( (t*d-s)*(2*PI)/p )) + b;
  }
  float postFix =  a*pow(2, -10*(t-=1)); // postIncrement is evil
  return postFix * sin( (t*d-s)*(2*PI)/p )*.5f + c + b;
}


float easeIn (float t, float b, float c, float d) {
  return c - easeOut (d-t, 0, c, d) + b;
}

float easeOut(float t, float b, float c, float d) {
  if ((t/=d) < (1/2.75f)) {
    return c*(7.5625f*t*t) + b;
  } else if (t < (2/2.75f)) {
    float postFix = t-=(1.5f/2.75f);
    return c*(7.5625f*(postFix)*t + .75f) + b;
  } else if (t < (2.5/2.75)) {
    float postFix = t-=(2.25f/2.75f);
    return c*(7.5625f*(postFix)*t + .9375f) + b;
  } else {
    float postFix = t-=(2.625f/2.75f);
    return c*(7.5625f*(postFix)*t + .984375f) + b;
  }
}

float easeInOut(float t, float b, float c, float d) {
  if (t < d/2) return easeIn (t*2, 0, c, d) * .5f + b;
  else return easeOut (t*2-d, 0, c, d) * .5f + c*.5f + b;
}