cam_pos      = [0.541373, 1.30981, -0.355781]';
cam_dir      = [-0.937426, -0.305427, -0.167175]';
cam_up       = [-0.286796, 0.94958, -0.126675]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.26259, 0.0941684, 1.30042]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;