How to get the normal direction of a surface ?

[[Mi...]]

Hello everyone,

I have a question for the community. I import a cloud of points that I polygonalize in order to obtain a surface but I do not know how to obtain information on the orientation of the normal vector? 
Someone knows how to do it? Or knows a manipulation to do in order to have this information?

 

Thanks everyone

[[Ja...]]

Im not sure i understand the root question.

A raw 'dumb' point cloud by itself doesnt inherently have normals

The software will take a guess on polygonisation .  The surface normal is coloured grey post polygonisation, you can always check by creating a surface point on it to see the direction of the normal of the surface at the point you clicked.

Does this help?

[[Mi...]]

Thank you for your answer ! 

I'm beginner on this software so can you explain me how to do that ?

[[Mi...]]

Hi Michael.
With your mesh selected hit the Tab key to see it's properties. In the display tab you will see that the Front of the mesh is coloured grey and the Rear of the mesh is coloured green as shown.

 

You can define a surface point on the mesh to see it's normal direction. Use Construct - Point - Surface Point from the menu then Ctrl and left click to define a point on the mesh. The normal direction is shown in the dialog box.

If your normal is incorrect it can easily be flipped. Use select through surface tool and select all of your mesh. From the menu select Operations - Mesh - Invert Selected Normals. Deselecting the mesh (Edit - Selection in 3D - Deselect All) shows the inverted normals of your mesh (grey and green are now inverted).

 

I hope this helps.