cam_pos      = [0.561396, 1.68262, 1.86347]';
cam_dir      = [0.498874, -0.169787, -0.849881]';
cam_up       = [-0.147449, 0.949699, -0.27628]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-1.13587, -0.349979, -0.596831]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;