3D Model Editor – Find Inconsistently Oriented Surface

Each simple triangle in the mesh structure of the 3D model has three vertices
The order of the three vertices is clockwise or counterclockwise.
In general, all cell vertices on a model are in the same order.
If it is not consistent, that is to say it has both clockwise and counterclockwise orders, it is recognized as a bad structure in some software.
Therefore, we also added a similar function to the online tool 3D model editor.
Firstly load your own model file, do not test with the existing model in the web page directly because it is a good model.
Open the detection model, it will calculate the normal vector of each cell.
Then find out a small number of cells with extremely different orientations,
Finally construct a new red surface, this red surface is the dissonant part.