int tubeRes = 32;
  float[] tubeX = new float[tubeRes];
  float[] tubeY = new float[tubeRes];
  PImage img;
  
  void setup() {
    size(640, 360, P3D);
    img = loadImage("berlin-1.jpg");
    float angle = 270.0 / tubeRes;
    for (int i = 0; i < tubeRes; i++) {
      tubeX[i] = cos(radians(i * angle));
      tubeY[i] = sin(radians(i * angle));
    }
    noStroke();
  }
  
  void draw() {
    background(0);
    translate(width / 2, height / 2);
    rotateX(map(mouseY, 0, height, -PI, PI));
    rotateY(map(mouseX, 0, width, -PI, PI));
    beginShape(QUAD_STRIP);
    texture(img);
    for (int i = 0; i < tubeRes; i++) {
      float x = tubeX[i] * 100;
      float z = tubeY[i] * 100;
      float u = img.width / tubeRes * i;
      vertex(x, -100, z, u, 0);
      vertex(x, 100, z, u, img.height);
    }
    endShape();
    beginShape(QUADS);
    texture(img);
    vertex(0, -100, 0, 0, 0);
    vertex(100, -100, 0, 100, 0);
    vertex(100, 100, 0, 100, 100);
    vertex(0, 100, 0, 0, 100);
    endShape();
  }