cam_pos      = [0.491374, 1.50336, 0.307139]';
cam_dir      = [-0.582511, 0.447224, -0.678728]';
cam_up       = [0.624664, 0.78059, -0.0217674]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.691698, 0.580752, 0.976309]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;