For all issues regarding the Forums use, please, refer to the Forum Rules.

Our Solutions

Need professional assistance?
Consider our:

Support Offerings


Need to speed up your development?
Have a look at our:

Samples & Tools


Need some functionality extending standard OCCT capabilities?
Check out our:

Adv. Components

Related pages

Normal of a triangle

Anonymous's picture


I have a problem to obtain the normal of a triangle (or a face)

Here is a litle example of what i did:

1/ I define a Face which have 3 vertices A:(0,0,0) B:(1,0,0) and C(1,1,0) 2/ I try to obtain U,V parameters with GeomAPI_ProjectPointOnSurf

the projectio of A gave me U=-1 V=0 and the projection of C gave me U=0 V=1 3/ I try to obtain the normal of the face by using BRepAdaptator_Surface BAS(myTrg); BRepLProp_SLProps (BAS,U,V,0,0);

When I asked the normal with U,V of C , the return was the right answers but when I ask the normal with U,V from A the function returned NAN,NAN,NAN ?

Have you an idea ? xav

Contact us

Attention: DO NOT use this form for all kind of request for the removal of your personal data. Please follow this link for such cases.