3dbox

PGraphics cubeA, cubeB, cubeC;
int frames = 240;
float theta;

void setup() {
  size(500, 500, P3D);
  cubeA = createGraphics(width, height, P3D);
  cubeB = createGraphics(width, height, P3D);
  cubeC = createGraphics(width, height, P3D);
  blendMode(DARKEST);
}

void draw() {
  background(255);
  drawCube(cubeA, 1, 2, #ffffff);
  drawCube(cubeB, 2, 1, #ffffff);
  drawCube(cubeC, 1, 1, #ffffff);
  image(cubeA, 0, 0);
  image(cubeB, 0, 0);
  image(cubeC, 0, 0);
  theta +=TWO_PI/frames;
  if (frameCount<=frames) saveFrame("image-###.tif");
}

void drawCube(PGraphics cube, float xd, float yd, color col) {
  cube.beginDraw();
  cube.lights();
  cube.clear();
  cube.noStroke();
  cube.fill(col);
  cube.translate(cube.width/2, cube.height/2);
  cube.rotateX(theta*xd);
  cube.rotateY(theta*yd);
  cube.box(cube.width/3);
  cube.endDraw();
}