cam_pos      = [0.275851, 1.77756, 0.845282]';
cam_dir      = [-0.935502, -0.269752, 0.228189]';
cam_up       = [-0.341041, 0.52061, -0.782724]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.122817, 1.07738, 0.770107]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;