cam_pos      = [-0.889394, 1.65915, -0.74652]';
cam_dir      = [-0.230749, 0.274523, 0.933484]';
cam_up       = [0.0229758, 0.960644, -0.276831]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [1.29375, 0.056433, 0.303207]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;