cam_pos      = [-0.260834, 0.520184, 1.4182]';
cam_dir      = [0.880245, 0.464294, -0.0979795]';
cam_up       = [-0.386533, 0.821346, 0.419504]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.36608, 0.440754, -1.20026]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;