Fix Orientation

I've been looking in the documentation and I don't see a MakeShell member function for BRepBuilder. The only available functions appear to be: Add, MakeCompound, MakeCompSolid, Remove, MakeEdge, MakeFace, MakeVertex, UpdateEdge, UpdateFace, UpdateVertex.

Also is there any way you could provide a more specific example of what you mean when you say use BRepBuilder::MakeShell and add the faces? I really don't know where to begin. Are there some samples you could point me toward? How much code/how long should it take me to get that done?

I have to go to work at 3pm until 8pm, but hopefully I'll be able to work on this stuff while I'm at work.

To everyone:
If anyone has already written an STL loader to load an STL file into a TopoDS_Shape I would greatly appreciate it if I could use it. I'm between sharp rocks and a lot of hard places right now, just a lot of due dates flying around plus im moving out of my apartment into a house. :-/

Stephane,

Thank you soooo much for all of your help. Once I used the BRepOffsetAPI_Sewing functionality it all worked, I then just have to Reverse the surface as it seems to be sewing them inside out. I appreciate your help more than you will ever know. But I am late to work so I need to go. Thanks!

I've attached the FINISHED function at the end of this reply. It should import an stl file located at 'FileName' and return its equivalent TopoDS_Shape.

Thanks to Stephane Routelous, PG, and Patrik Müller for making this happen.

----------------------------------------------------------------------
TopoDS_Shape
importedFile(string FileName)
{
OSD_Path aFile((char*)FileName.c_str());
Standard_Boolean ReturnValue = Standard_True;

Handle(StlMesh_Mesh) aSTLMesh = RWStl::ReadFile(aFile);

TopoDS_Shell ResultShell;
BRep_Builder ShellBuilder;
ShellBuilder.MakeShell(ResultShell);

Standard_Integer NumberDomains = aSTLMesh->NbDomains();
Standard_Integer iND;
gp_XYZ p1, p2, p3;
TopoDS_Vertex Vertex1, Vertex2, Vertex3;
TopoDS_Face AktFace;
TopoDS_Wire AktWire;
BRep_Builder B;
Standard_Real x1, y1, z1;
Standard_Real x2, y2, z2;
Standard_Real x3, y3, z3;

StlMesh_MeshExplorer aMExp (aSTLMesh);

// BRepBuilderAPI_MakeWire WireCollector;
for (iND=1;iND<=NumberDomains;iND++)
{
for (aMExp.InitTriangle (iND); aMExp.MoreTriangle (); aMExp.NextTriangle ())
{
aMExp.TriangleVertices (x1,y1,z1,x2,y2,z2,x3,y3,z3);
p1.SetCoord(x1,y1,z1);
p2.SetCoord(x2,y2,z2);
p3.SetCoord(x3,y3,z3);

if ((!(p1.IsEqual(p2,0.0))) && (!(p1.IsEqual(p3,0.0))))
{
Vertex1 = BRepBuilderAPI_MakeVertex(p1);
Vertex2 = BRepBuilderAPI_MakeVertex(p2);
Vertex3 = BRepBuilderAPI_MakeVertex(p3);

AktWire = BRepBuilderAPI_MakePolygon( Vertex1, Vertex2, Vertex3, Standard_True);

if( !AktWire.IsNull())
{
AktFace = BRepBuilderAPI_MakeFace( AktWire);
if(!AktFace.IsNull())
ShellBuilder.Add(ResultShell,AktFace);
}
}
}
}

BRepOffsetAPI_Sewing sew;
sew.Add(ResultShell);
sew.Perform();
TopoDS_Shape newshape = sew.SewedShape();

newshape.Reverse();

return newshape;
}
----------------------------------------------------------------------

I spoke just a wee bit too soon. For some reason I can't take the union of one of the stl files that I imported and a (BRepPrimAPI_MakeBox) box.

When I try and take the union it fails with the BRepAlgoAPI_BooleanOperation::ErrorStatus() of value 110. I looked in the documentation and it states that: If the error is more than 100 - The error is during second part of the operation.

The second part of the operation is aparently building the result of the operation after the interference has already been calculated.

There doesn't appear to be anything else in the documentation that says anything about why it would error in this second part of the operation. Do you know what might be happening?