cam_pos      = [0.497913, 1.49872, 0.298469]';
cam_dir      = [-0.64583, 0.337403, -0.684881]';
cam_up       = [0.467869, 0.883779, -0.00580316]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.802422, 0.431163, 0.969081]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;