l.TRIANGLES;
    var offset = 0;
    var count = 16 * 6;
    gl.drawArrays(primitiveType, offset, count);

    // Call drawScene again next frame
    requestAnimationFrame(drawScene);
  }
}

// Fill the current ARRAY_BUFFER buffer
// with the values that define a letter 'F'.
function setGeometry(gl) {
  var positions = new Float32Array([
          // left column front
          0,   0,  0,
          0, 150,  0,
          30,   0,  0,
          0, 150,  0,
          30, 150,  0,
          30,   0,  0,

     