cam_pos      = [0.17982, 1.70755, 0.834269]';
cam_dir      = [-0.94771, -0.11189, 0.298876]';
cam_up       = [-0.307893, 0.566939, -0.764057]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.111659, 1.08545, 0.760418]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;