cam_pos      = [-0.594101, 1.19396, 0.140252]';
cam_dir      = [-0.431847, 0.173413, -0.885119]';
cam_up       = [0.897951, 0.174934, -0.403834]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.112794, 1.28902, 0.307577]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;