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

the normal vector of point is opposite

xiangchunkong's picture

I get the Normal vector of points on the model with two way:
first way:
1.use Geom_Surface::D1(u,v,pt,vec1,vec2)
2.vecResult = vec1^vec2(cross product)

second way:
1.use BRepGProp_Face propsface(face);propsface.Normal(SRU,SRV,gpPt,vecResult);

i get the normal vector of the point ,but sometime the normal vector is opposite that direction toward the models's inside

Thanks for any help