suzanne.soy/FreeCAD
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

PartDesign, Transformed features: Improved intersection check

Browse Source
This commit is contained in:
jrheinlaender 2012-10-22 16:02:01 +02:00 committed by logari81
parent 1c158ef924
commit 32628462c2
3 changed files with 54 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
src/Mod/Part/App/PartFeature.cpp
View File

@ -27,14 +27,16 @@
# include <gp_Trsf.hxx>
# include <gp_Ax1.hxx>
# include <BRepBuilderAPI_MakeShape.hxx>
# include <BRepAlgoAPI_Common.hxx>
# include <TopTools_ListIteratorOfListOfShape.hxx>
# include <TopExp.hxx>
# include <TopTools_IndexedMapOfShape.hxx>
# include <Standard_Failure.hxx>
// includes for findAllFacesCutBy()
# include <TopoDS_Face.hxx>
# include <gp_Dir.hxx>
# include <gp_Pln.hxx> // for Precision::Confusion()
# include <Bnd_Box.hxx>
# include <BRepBndLib.hxx>
#endif
@ -333,3 +335,34 @@ std::vector<Part::cutFaces> Part::findAllFacesCutBy(
return result;
}
const bool Part::checkIntersection(const TopoDS_Shape& first, const TopoDS_Shape& second, const bool quick) {
Bnd_Box first_bb, second_bb;
BRepBndLib::Add(first, first_bb);
first_bb.SetGap(0);
BRepBndLib::Add(second, second_bb);
second_bb.SetGap(0);
// Note: Both tests fail if the objects are touching one another at zero distance!
if (first_bb.IsOut(second_bb))
return false; // no intersection
//if (first_bb.Distance(second_bb) > Precision::Confusion())
// return false;
if (quick)
return true; // assumed intersection
// Try harder
BRepAlgoAPI_Common mkCommon(first, second);
// FIXME: Error in boolean operation, return true by default
if (!mkCommon.IsDone())
return true;
if (mkCommon.Shape().IsNull())
return true;
TopExp_Explorer xp;
xp.Init(mkCommon.Shape(),TopAbs_SOLID);
if (xp.More())
return true;
return false;
}

10
src/Mod/Part/App/PartFeature.h
View File

@ -135,6 +135,16 @@ PartExport
std::vector<cutFaces> findAllFacesCutBy(const TopoDS_Shape& shape,
const TopoDS_Shape& face, const gp_Dir& dir);
/**
* Check for intersection between the two shapes. Only solids are guaranteed to work properly
* There are two modes:
* 1. Bounding box check only - quick but inaccurate
* 2. Bounding box check plus (if necessary) boolean operation - costly but accurate
* Return true if the shapes intersect, false if they don't
*/
PartExport
const bool checkIntersection(const TopoDS_Shape& first, const TopoDS_Shape& second, const bool quick = true);
} //namespace Part

30
src/Mod/PartDesign/App/FeatureTransformed.cpp
View File

@ -30,8 +30,6 @@
# include <TopExp.hxx>
# include <TopExp_Explorer.hxx>
# include <TopTools_IndexedMapOfShape.hxx>
# include <Bnd_Box.hxx>
# include <BRepBndLib.hxx>
# include <Precision.hxx>
# include <BRepBuilderAPI_Copy.hxx>
#endif
@ -114,10 +112,6 @@ App::DocumentObjectExecReturn *Transformed::execute(void)
supportShape.setTransform(Base::Matrix4D());
TopoDS_Shape support = supportShape._Shape;
// Prepare a bounding box for intersection tests
Bnd_Box support_bb;
BRepBndLib::Add(support, support_bb);
// NOTE: It would be possible to build a compound from all original addShapes/subShapes and then
// transform the compounds as a whole. But we choose to apply the transformations to each
// Original separately. This way it is easier to discover what feature causes a fuse/cut
@ -162,9 +156,7 @@ App::DocumentObjectExecReturn *Transformed::execute(void)
return new App::DocumentObjectExecReturn("Transformation failed", (*o));
// Check for intersection with support
Bnd_Box transformed_bb;
BRepBndLib::Add(mkTrf.Shape(), transformed_bb);
if (support_bb.Distance(transformed_bb) > Precision::Confusion()) {
if (!Part::checkIntersection(support, mkTrf.Shape(), false)) {
Base::Console().Warning("Transformed shape does not intersect support %s: Removed\n", (*o)->getNameInDocument());
// Note: The removal happens in getSolid() after the fuse. If we remove here,
// the histories get messed up and we get a crash
@ -193,11 +185,6 @@ App::DocumentObjectExecReturn *Transformed::execute(void)
}
// Check for intersection of the original and the transformed shape
// Note: For performance reasons, we only check for intersection of bounding boxes
Bnd_Box original_bb;
BRepBndLib::Add(shape, original_bb);
original_bb.SetGap(0);
for (std::vector<TopoDS_Shape>::const_iterator s = v_transformedShapes.begin(); s != v_transformedShapes.end(); s++)
{
// If there is only one transformed feature, this check is not necessary (though it might seem
@ -205,12 +192,7 @@ App::DocumentObjectExecReturn *Transformed::execute(void)
if (v_transformedShapes.size() == 1)
break;
Bnd_Box transformed_bb;
BRepBndLib::Add(*s, transformed_bb);
transformed_bb.SetGap(0);
if (!original_bb.IsOut(transformed_bb))
// if (original_bb.Distance(transformed_bb) < Precision::Confusion())
// FIXME: Both tests fail if the objects are touching one another at zero distance
if (Part::checkIntersection(shape, *s, false))
return new App::DocumentObjectExecReturn("Transformed objects are overlapping, try using a higher length or reducing the number of occurrences", (*o));
// Note: This limitation could be overcome by fusing the transformed features instead of
// compounding them, probably at the expense of quite a bit of performance and complexity
@ -220,6 +202,14 @@ App::DocumentObjectExecReturn *Transformed::execute(void)
// features might overlap, even if the original and the first shape don't overlap!
if (this->getTypeId() != PartDesign::MultiTransform::getClassTypeId())
break;
else {
// Check intersection with all other transformed shapes as well
std::vector<TopoDS_Shape>::const_iterator s2 = s;
s2++;
for (; s2 != v_transformedShapes.end(); s2++)
if (Part::checkIntersection(*s, *s2, false))
return new App::DocumentObjectExecReturn("Transformed objects are overlapping, try using a higher length or reducing the number of occurrences", (*o));
}
}
// Fuse/Cut the compounded transformed shapes with the support