cam_pos      = [0.771744, 1.72683, 1.15997]';
cam_dir      = [-0.410335, 0.101752, -0.906241]';
cam_up       = [-0.379795, 0.884404, 0.271266]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-1.10268, -0.605808, 0.431262]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;