cam_pos      = [0.604583, 1.58414, 0.270656]';
cam_dir      = [-0.829812, -0.44375, -0.338376]';
cam_up       = [-0.233305, 0.826697, -0.511997]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.674221, 0.460068, 1.05008]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;