Area inside a closed TopoDS_Wire on the surface of a TopoDS_Shell

Hi!

I am also interested in that question. Does OCC offer surface area computation algorithms besides computation of the surface area of a whole shell?

Isn't this a very basic and important task?

Benjamin

Hello,

I have not tested the following, but it should work:
1) Project wire onto face
2) ensure wire is only on the face you want (may have to trim)
3) Use BRepFeat_SplitShape to split the face and the wire
4) Use BRepGProp::SurfaceProperties and GProp_GProps::Mass to get the area of that face
BRepGProp::SurfaceProperties(shape, props);
double aGeomArea = props.Mass();

Good luck

Hello Mohamed,

A possible approach to solving your problem could consist of the following steps:
- Apply General Fuse operation to your shell and wire
- Find the wire contour inside the new shell
- Find the faces that contain edges of that contour
- Select faces that are inside the contour
- Create a new shell out of them

Here is a simple example in Draw how to apply General Fuse operation to a shell and a wire:

# Load modeling commands
pload MODELING
# Create a shell
polyline p1 0 0 0 10 0 0 10 5 0 10 10 0 0 10 0 0 0 0
prism r1 p1 0 0 10
# Create a wire
polyline p2 10 2 2 10 8 2 10 8 8 10 2 8 10 2 2
# Clear arguments (optional, only needed if calling repeatedly)
bcleartools
bclearobjects
# Apply General Fuse
baddobjects r1 p2
bapibuild r
# Show the result
axo; donly r; fit

We shall be glad to offer our additional assistance in the frames of a support program, if you are interested.
Contact us at http://www.opencascade.com/contact for more information.

Best regards,
Forum supervisor