cam_pos      = [-0.797975, 1.32037, -0.0738279]';
cam_dir      = [0.224569, 0.157056, 0.961718]';
cam_up       = [0.52699, 0.810578, -0.25543]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [1.09015, -0.750357, -0.132021]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;