Wrong face problem

I try to develop the skp to obj.

some skp file have a wrong face orientation

but, in sketchup, show a right .

however i search a sdk documentation

but for that case, there is not

how can i resolve the problem

You need to attach the SKP file, and some code that shows the problem.
Images also help to describe what is happening.

REF: How to post code in the forum

There is also this function for the model object: