cam_pos      = [0.358565, 1.81803, 0.835782]';
cam_dir      = [-0.935111, -0.273074, 0.225826]';
cam_up       = [-0.322624, 0.392504, -0.86131]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.194929, 1.16811, 0.60533]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;