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#include <ShapeConstruct_MakeTriangulation.ixx>
#include <TColStd_SequenceOfInteger.hxx>
#include <Precision.hxx>
#include <gp_Pln.hxx>
#include <gp_Vec.hxx>
#include <Geom_Plane.hxx>
#include <TColStd_Array1OfInteger.hxx>
#include <TColgp_HArray1OfPnt.hxx>
#include <TColgp_SequenceOfPnt.hxx>
#include <TopoDS.hxx>
#include <TopoDS_Shell.hxx>
#include <TopoDS_Face.hxx>
#include <TopoDS_Edge.hxx>
#include <TopoDS_Iterator.hxx>
#include <BRep_Tool.hxx>
#include <BRep_Builder.hxx>
#include <TopTools_HSequenceOfShape.hxx>
#include <BRepBuilderAPI_MakePolygon.hxx>
#include <BRepBuilderAPI_MakeEdge.hxx>
#include <ShapeAnalysis_Edge.hxx>
#include <ShapeAnalysis_Wire.hxx>
#include <ShapeAnalysis_Curve.hxx>
//=======================================================================
//function : IsRightContour (static)
//purpose :
//=======================================================================
Standard_Boolean IsRightContour (const TColgp_SequenceOfPnt& pts, const Standard_Real prec)
{
Standard_Integer len = pts.Length();
if (len < 4) return Standard_True;
TColgp_Array1OfPnt thePts(1,len);
Standard_Integer i; // svv Jan11 2000 : porting on DEC
for (i = 1; i <= len; i++) thePts(i) = pts(i);
gp_XYZ Norm(0,0,0);
if (ShapeAnalysis_Curve::IsPlanar(thePts,Norm,prec)) {
// Make polygonal wire from points
BRepBuilderAPI_MakePolygon mkPoly;
for (i = 1; i <= len; i++) mkPoly.Add(thePts(i));
mkPoly.Close();
mkPoly.Build();
if (mkPoly.IsDone()) {
// Create mean plane
gp_XYZ center(0,0,0);
for (i = 1; i <= len; i++) center += thePts(i).XYZ();
center /= len;
gp_Pnt pc(center); gp_Dir pd(Norm); gp_Pln pl(pc,pd);
Handle(Geom_Plane) thePlane = new Geom_Plane(pl);
BRep_Builder B;
TopoDS_Face theFace;
B.MakeFace(theFace,thePlane,Precision::Confusion());
TopoDS_Wire theWire = mkPoly.Wire();
B.Add(theFace,theWire);
Handle(ShapeAnalysis_Wire) saw = new ShapeAnalysis_Wire(theWire,theFace,prec);
return !saw->CheckSelfIntersection();
}
}
return Standard_False;
}
//=======================================================================
//function : MeanNormal (static)
//purpose :
//=======================================================================
gp_Vec MeanNormal (const TColgp_Array1OfPnt& pts)
{
Standard_Integer len = pts.Length();
if (len < 3) return gp_Vec(0,0,0);
Standard_Integer i;
gp_XYZ theCenter(0,0,0);
for (i = 1; i <= len; i++) theCenter += pts(i).XYZ();
theCenter /= len;
gp_XYZ theNorm(0,0,0);
for (i = 1; i <= len; i++) {
gp_Vec v1(pts(i).XYZ() - theCenter);
gp_Vec v2(pts((i==len)? 1 : i+1).XYZ() - theCenter);
theNorm += (v1^v2).XYZ();
}
return gp_Vec(theNorm).Normalized();
}
//=======================================================================
//function : ShapeConstruct_MakeTriangulation
//purpose :
//=======================================================================
ShapeConstruct_MakeTriangulation::ShapeConstruct_MakeTriangulation (const TColgp_Array1OfPnt& pnts,
const Standard_Real prec)
{
myPrecision = (prec > 0.0)? prec : Precision::Confusion();
// Make polygonal wire from points
BRepBuilderAPI_MakePolygon mkPoly;
for (Standard_Integer i = pnts.Lower(); i <= pnts.Upper(); i++) mkPoly.Add(pnts(i));
mkPoly.Close();
mkPoly.Build();
if (mkPoly.IsDone()) {
myWire = mkPoly.Wire();
Build();
}
}
//=======================================================================
//function : ShapeConstruct_MakeTriangulation
//purpose :
//=======================================================================
ShapeConstruct_MakeTriangulation::ShapeConstruct_MakeTriangulation (const TopoDS_Wire& wire,
const Standard_Real prec)
{
myPrecision = (prec > 0.0)? prec : Precision::Confusion();
myWire = wire;
Build();
}
//=======================================================================
//function : Build
//purpose :
//=======================================================================
void ShapeConstruct_MakeTriangulation::Build()
{
if (myShape.IsNull()) {
// Triangulate polygonal wire
if (!myWire.IsNull()) Triangulate(myWire);
}
}
//=======================================================================
//function : IsDone
//purpose :
//=======================================================================
Standard_Boolean ShapeConstruct_MakeTriangulation::IsDone() const
{
return (!myShape.IsNull());
}
//=======================================================================
//function : Triangulate
//purpose :
//=======================================================================
void ShapeConstruct_MakeTriangulation::Triangulate (const TopoDS_Wire& wire)
{
// Fill sequence of edges
Handle(TopTools_HSequenceOfShape) theEdges = new TopTools_HSequenceOfShape;
for (TopoDS_Iterator ite(wire); ite.More(); ite.Next()) theEdges->Append(ite.Value());
Standard_Integer NbEdges = theEdges->Length();
if (NbEdges < 4) AddFacet(wire);
else {
// Fill array of end points
ShapeAnalysis_Edge sae;
Handle(TColgp_HArray1OfPnt) theAPnt = new TColgp_HArray1OfPnt(1,NbEdges);
for (Standard_Integer i = 1; i <= NbEdges; i++)
theAPnt->SetValue(i,BRep_Tool::Pnt(sae.FirstVertex(TopoDS::Edge(theEdges->Value(i)))));
TopoDS_Wire theNewWire;
// Check planarity on array of points
gp_XYZ Norm(0,0,0);
if (ShapeAnalysis_Curve::IsPlanar(theAPnt->Array1(),Norm,myPrecision)) AddFacet(wire);
else {
// Current contour is not planar - triangulate
TColStd_SequenceOfInteger theSegments;
Standard_Integer cindex = 1, seqFlag = 1;
TColStd_Array1OfInteger llimits(1,2), rlimits(1,2);
llimits.Init(NbEdges+1); rlimits.Init(0);
// Find all "good" planar segments
while (seqFlag) {
// Set up limits for current sequence
Standard_Integer llimit = llimits(seqFlag);
Standard_Integer rlimit = rlimits(seqFlag);
if (rlimit <= llimit) rlimit += NbEdges;
// Check stop condition
if ((rlimit - llimit) > (NbEdges - 2)) break;
TColgp_SequenceOfPnt theSPnt;
// Add 3 points of minimal facet
Standard_Integer lindex = (cindex==1? NbEdges : cindex-1);
Standard_Integer rindex = (cindex==NbEdges? 1 : cindex+1);
theSPnt.Append(theAPnt->Value(lindex));
theSPnt.Append(theAPnt->Value(cindex));
theSPnt.Append(theAPnt->Value(rindex));
// Try prepending points
Standard_Boolean isGood = Standard_True;
while (isGood) {
cindex = (lindex==1? NbEdges : lindex-1);
if (cindex == rindex) { AddFacet(wire); return; }
Standard_Integer cid = cindex;
if (rlimit > NbEdges && cid <= llimit) cid += NbEdges;
if (cid > llimit && cid < rlimit) isGood = Standard_False;
if (isGood) {
theSPnt.Prepend(theAPnt->Value(cindex));
isGood = IsRightContour(theSPnt,myPrecision);
if (isGood) lindex = cindex;
else theSPnt.Remove(1);
}
}
// Try appending points
isGood = Standard_True;
while (isGood) {
cindex = (rindex==NbEdges? 1 : rindex+1);
if (cindex == lindex) { AddFacet(wire); return; }
Standard_Integer cid = cindex;
if (rlimit > NbEdges && cid <= llimit) cid += NbEdges;
if (cid > llimit && cid < rlimit) isGood = Standard_False;
if (isGood) {
theSPnt.Append(theAPnt->Value(cindex));
isGood = IsRightContour(theSPnt,myPrecision);
if (isGood) rindex = cindex;
else theSPnt.Remove(theSPnt.Length());
}
}
// Record new planar segment
theSegments.Append(lindex);
theSegments.Append(rindex);
// Set up new limits
cindex = rindex;
rlimits(seqFlag) = rindex;
if (llimit > NbEdges) llimits(seqFlag) = lindex;
// Set up sequence index
seqFlag = (seqFlag == 1)? 2 : 1;
}
cindex = theSegments.Length();
if (cindex%4 == 0) {
gp_Vec theBaseNorm = MeanNormal(theAPnt->Array1());
// Identify sequence of matching facets
Standard_Integer len = cindex/2, lindex, rindex, seqlen, j;
Standard_Real theC, theC1 = 0.0, theC2 = 0.0;
Standard_Integer ii; // svv Jan11 2000 : porting on DEC
// skl : change "i" to "ii"
for (ii = 0; ii < len; ii++) {
// Compute normal collinearity for facet
lindex = theSegments(ii*2+1);
rindex = theSegments(ii*2+2);
seqlen = ((rindex > lindex)? rindex - lindex + 1 : NbEdges - lindex + rindex + 1);
TColgp_Array1OfPnt theArr(1,seqlen);
for (j = 1; j <= seqlen; j++) {
theArr(j) = theAPnt->Value(lindex);
lindex++;
if (lindex > NbEdges) lindex = 1;
}
theC = theBaseNorm*MeanNormal(theArr);
if (ii%2) theC2 += theC; else theC1 += theC;
}
Standard_Integer best1 = ((theC1 > theC2)? 0 : 2);
// Add "best" planar facets
BRep_Builder B;
TopoDS_Wire theFacetWire;
TopoDS_Edge theLEdge, theSLEdge;
len = cindex/4;
// Check for special case - 1 shared line
Standard_Boolean special = (len == 2 &&
theSegments(best1+1) == theSegments(4+best1+2) &&
theSegments(best1+2) == theSegments(4+best1+1));
Standard_Integer pindex = theSegments((len-1)*4+best1+2);
for (ii = 0; ii < len; ii++) {
lindex = theSegments(ii*4+best1+1);
rindex = theSegments(ii*4+best1+2);
if (special && !theSLEdge.IsNull()) {
TopoDS_Shape aLocalShape = theSLEdge.Reversed();
theLEdge = TopoDS::Edge(aLocalShape);
// theLEdge = TopoDS::Edge(theSLEdge.Reversed());
}
else {
TopoDS_Vertex v1 = sae.FirstVertex(TopoDS::Edge(theEdges->Value(lindex)));
TopoDS_Vertex v2 = sae.FirstVertex(TopoDS::Edge(theEdges->Value(rindex)));
v1.Orientation(TopAbs_FORWARD);
v2.Orientation(TopAbs_REVERSED);
theLEdge = BRepBuilderAPI_MakeEdge(v1,v2);
theSLEdge = theLEdge;
}
// Create new facet wire
B.MakeWire(theFacetWire);
B.Add(theFacetWire,theLEdge.Reversed());
Standard_Integer cur_edge = lindex;
while (cur_edge != rindex) {
TopoDS_Edge theNEdge = TopoDS::Edge(theEdges->Value(cur_edge));
B.Add(theFacetWire,theNEdge);
if (cur_edge == NbEdges) cur_edge = 1;
else cur_edge++;
}
AddFacet(theFacetWire);
if (!special) {
// Add edges to the new wire
if (theNewWire.IsNull()) B.MakeWire(theNewWire);
cur_edge = pindex;
while (cur_edge != lindex) {
TopoDS_Edge theNEdge = TopoDS::Edge(theEdges->Value(cur_edge));
B.Add(theNewWire,theNEdge);
if (cur_edge == NbEdges) cur_edge = 1;
else cur_edge++;
}
B.Add(theNewWire,theLEdge);
pindex = rindex;
}
}
}
// Clear storage variables
theEdges.Nullify();
theAPnt.Nullify();
// Triangulate the rest of edges
if (!theNewWire.IsNull()) Triangulate(theNewWire);
}
}
}
//=======================================================================
//function : AddFacet
//purpose :
//=======================================================================
void ShapeConstruct_MakeTriangulation::AddFacet (const TopoDS_Wire& wire)
{
if (wire.IsNull()) return;
// Fill sequence of points
ShapeAnalysis_Edge sae;
TColgp_SequenceOfPnt pts;
for (TopoDS_Iterator ite(wire); ite.More(); ite.Next())
pts.Append(BRep_Tool::Pnt(sae.FirstVertex(TopoDS::Edge(ite.Value()))));
Standard_Integer i, nbp = pts.Length();
if (nbp < 3) return;
// Create mean plane
Standard_Real cMod, maxMod = 0.0;
gp_XYZ maxVec, Normal(0,0,0);
for (i = 1; i <= nbp; i++) {
gp_XYZ vb(pts(i).XYZ());
gp_XYZ v1(pts(i==nbp? 1 : i+1).XYZ()-vb);
cMod = v1.SquareModulus();
if (cMod == 0.0) continue;
else if (cMod > maxMod) { maxMod = cMod; maxVec = v1; }
gp_XYZ v2(pts(i==1? nbp : i-1).XYZ()-vb);
cMod = v2.SquareModulus();
if (cMod == 0.0) continue;
else if (cMod > maxMod) { maxMod = cMod; maxVec = v2; }
Normal += gp_XYZ(v1^v2);
}
if (Normal.SquareModulus() == 0.0) {
if (maxMod == 0.0)
Normal = gp_XYZ(0,0,1);
else if (maxVec.X() != 0.0)
Normal = gp_XYZ(-maxVec.Y()/maxVec.X(),1,0);
else if (maxVec.Y() != 0.0)
Normal = gp_XYZ(0,-maxVec.Z()/maxVec.Y(),1);
else
Normal = gp_XYZ(1,0,0);
}
gp_Pln Pln(pts(1),gp_Dir(Normal));
Handle(Geom_Plane) thePlane = new Geom_Plane(Pln);
// Mean plane created - build face
BRep_Builder B;
TopoDS_Face theFace;
B.MakeFace(theFace,thePlane,Precision::Confusion());
B.Add(theFace,wire);
// Add new face to the shell
if (myShape.IsNull()) myShape = theFace;
else {
if (myShape.ShapeType() == TopAbs_FACE) {
TopoDS_Face firstFace = TopoDS::Face(myShape);
TopoDS_Shell theShell;
B.MakeShell(theShell);
myShape = theShell;
B.Add(myShape,firstFace);
}
B.Add(myShape,theFace);
}
}
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