[Openflipper] How to get face area and how to iterate vertices of a face in counterclockwise

Dear Openflipper, We have two questions. Hopefully we can get answers from you. 1). We can not use the following formula to get the right face area . 0.5* (((p1-p0) * (p2-p0)).norm()); For instance, the right value should be 0.145643363, but we got 0.0874207. x y z 0.2649 0.1398 4.8136 0.7567 0.0491 4.8185 0.6181 -0.0791 4.2549 i j k 0.4918 -0.0907 0.0049 0.3532 -0.2189 -0.5587 0.0517467 0.27649934 -0.07562 0.002677721 0.076451885 0.005718 0.084848 0.145643 2). How to iterate vertices of a face in counterclockwise? Thank you very much! Best Regards, Xianyong Liu.