cam_pos      = [0.325161, 1.7841, 0.832879]';
cam_dir      = [-0.935111, -0.273074, 0.225826]';
cam_up       = [-0.32245, 0.391465, -0.861848]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.195437, 1.16873, 0.603974]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;