OLED black smearing test for Processing 3.4

oledtest.pde

// OLED black smearing test for Processing 3.4.
// Black smearing = changing pixels to and from pure black is slower than changing to and from other colours.
//
// Code by @marcedwards from @bjango.

void setup() {
  size(360, 360, P2D);
  frameRate(60);
  smooth(8);
  noStroke();
}

void draw() {
  background(0);

  float ypos = easeInOutSin(easeTriangle(timeCycle(40))) * 140;

  fill(40);
  rect(100, ypos + 30, 160, 160);

  fill(200);
  rect(130, ypos + 60, 100, 100);

  //render(40);
}

float timeCycle(int totalframes, int offset) {
  return float((frameCount + offset) % totalframes) / float(totalframes);
}

float timeCycle(int totalframes) {
  return timeCycle(totalframes, 0);
}

float easeTriangle(float t) {
  return t<0.5 ? t*2 : 2-(t*2);
}

float easeInOutSin(float t) {
  return 0.5+sin(PI*t-PI/2)/2;
}

void render(int frames, String foldername) {
  saveFrame(foldername + "/frame####.png");
  if (frameCount == frames) {
    exit();
  }
}

void render(int frames) {
  render(frames, "render");
}

void render(String foldername) {
  render(100, foldername);
}

void render() {
  render(100, "render");
}