Intersection of tangent surfaces


I have two surface to intersect. One surface is perfectly tangent to the
inside of the other surface.

I used IntTools_FaceFace but it seems that this case is not handled.
I see that from IntPolyh_Intersection, are found some sectionLines and one tangentZone
but they are partial and are not able to produce the exact solution.

How can I handle such a case?


marlanzo's picture

I add here a brep file containing the two surfaces.
Use the following instructions in DRAW to reproduce the case.

restore twosurfaces.brep shape
explode shape
intersect ints shape_1 shape_2
dump ints

(int is empty).

Evgeny Lodyzhehsky's picture

Dear marco lanzoni,

1. The comьand "intersect" is intended to work with geometry (curves, surfaces)
The objects shape_1, shape_2 are faces (shapes).
So the fact that "...(int is empty)..." is Ok.

2. The face 'shape_2' is self-intersected shape.
You can have a look using the command:
>bopcheck shape_2
The direct usage of 'shape_2' is impossible.
So you need to take away the self-intersection first.

Let's allow that there are not self-intersecions in 'shape_2':
>mksurface s2 shape_2
>mkface f2 s2
The face 'f2' is not self-intersected. Fell a difference with 'shape_2"

Then intersect the shapes 'shape_1', 'f2':
>bop shape_1 f2
>bopsection t
Is the shape 't' what you wanted?