- // try to build face on plane or on any surface under the edges of the wire
- BRepBuilderAPI_MakeFace MK (theWire, isPlanarWanted);
- if (MK.IsDone()) {
- theResult = MK.Shape();
- return;
+ TCollection_AsciiString aWarning;
+
+ // Workaround for Mantis issue 0020956
+ if (isPlanarWanted) {
+ // Count the number of points in the wire.
+ // Collect the first three points.
+ gp_Pnt p1, p2, p3;
+ bool is3Pnts(false);
+ bool p1set(false), p2set(false), p3set(false);
+ BRepTools_WireExplorer wexpl(theWire);
+ for (; wexpl.More(); wexpl.Next()) {
+ if (!p1set) {
+ p1set = true;
+ p1 = BRep_Tool::Pnt(wexpl.CurrentVertex());
+ }
+ else if (!p2set) {
+ p2set = true;
+ p2 = BRep_Tool::Pnt(wexpl.CurrentVertex());
+ }
+ else if (!p3set) {
+ p3set = true;
+ is3Pnts = true;
+ p3 = BRep_Tool::Pnt(wexpl.CurrentVertex());
+ }
+ else {
+ is3Pnts = false;
+ break;
+ }
+ }
+
+ // Construct a plane for the case of three points in the wire.
+ gp_Pln plane;
+ if (is3Pnts) {
+ gce_MakePln mkPln(p1, p2, p3);
+ if (mkPln.IsDone()) {
+ plane = mkPln.Value();
+ }
+ else {
+ is3Pnts = false;
+ }
+ }
+
+ // Construct a face based on the plane (in case of three points in the wire) or
+ // allow MakeFace to build the plane itself (in case of the number of points is greater than 3).
+ if (is3Pnts) {
+ BRepBuilderAPI_MakeFace MK (plane, theWire, isPlanarWanted);
+ if (MK.IsDone()) {
+ theResult = MK.Shape();
+ return aWarning;
+ }
+ }
+ else {
+ BRepBuilderAPI_MakeFace MK (theWire, isPlanarWanted);
+ if (MK.IsDone()) {
+ theResult = MK.Shape();
+ return aWarning;
+ }
+ }
+ }
+ else {
+ // try to build face on plane or on any surface under the edges of the wire
+ BRepBuilderAPI_MakeFace MK (theWire, isPlanarWanted);
+ if (MK.IsDone()) {
+ theResult = MK.Shape();
+ return aWarning;
+ }