cam_pos      = [-0.853996, 1.50374, -1.24339]';
cam_dir      = [-0.378722, 0.236701, 0.89473]';
cam_up       = [-0.0722883, 0.956224, -0.283568]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [1.22717, 0.228856, 0.458893]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;