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 * ***** BEGIN GPL LICENSE BLOCK *****
 *
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 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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/** \file blender/freestyle/intern/view_map/ViewEdgeXBuilder.cpp
 *  \ingroup freestyle
 *  \brief Class to build view edges and the underlying chains of feature edges...
 *  \author Stephane Grabli
 *  \date 27/10/2003
 */

#include <list>

#include "SilhouetteGeomEngine.h"
#include "ViewEdgeXBuilder.h"
#include "ViewMap.h"

#include "../winged_edge/WXEdge.h"

using namespace std;

namespace Freestyle {

void ViewEdgeXBuilder::Init(ViewShape *oVShape)
{
	if (NULL == oVShape)
		return;

	// for design conveniance, we store the current SShape.
	_pCurrentSShape = oVShape->sshape();
	if (0 == _pCurrentSShape)
		return;

	_pCurrentVShape = oVShape;

	// Reset previous data
	//--------------------
	if (!_SVertexMap.empty())
		_SVertexMap.clear();
}

void ViewEdgeXBuilder::BuildViewEdges(WXShape *iWShape, ViewShape *oVShape, vector<ViewEdge*>& ioVEdges,
                                      vector<ViewVertex*>& ioVVertices, vector<FEdge*>& ioFEdges,
                                      vector<SVertex*>& ioSVertices)
{
	// Reinit structures
	Init(oVShape);

	/* ViewEdge *vedge; */ /* UNUSED */
	// Let us build the smooth stuff
	//----------------------------------------
	// We parse all faces to find the ones that contain smooth edges
	vector<WFace*>& wfaces = iWShape->GetFaceList();
	vector<WFace*>::iterator wf, wfend;
	WXFace *wxf;
	for (wf = wfaces.begin(), wfend = wfaces.end(); wf != wfend; wf++) {
		wxf = dynamic_cast<WXFace*>(*wf);
		if (false == ((wxf))->hasSmoothEdges()) // does it contain at least one smooth edge ?
			continue;
		// parse all smooth layers:
		vector<WXFaceLayer*>& smoothLayers = wxf->getSmoothLayers();
		for (vector<WXFaceLayer*>::iterator sl = smoothLayers.begin(), slend = smoothLayers.end(); sl != slend; ++sl) {
			if (!(*sl)->hasSmoothEdge())
				continue;
			if (stopSmoothViewEdge((*sl))) // has it been parsed already ?
				continue;
			// here we know that we're dealing with a face layer that has not been processed yet and that contains
			// a smooth edge.
			/* vedge =*/ /* UNUSED */ BuildSmoothViewEdge(OWXFaceLayer(*sl, true));
		}
	}

	// Now let's build sharp view edges:
	//----------------------------------
	// Reset all userdata for WXEdge structure
	//----------------------------------------
	//iWShape->ResetUserData();

	WXEdge *wxe;
	vector<WEdge*>& wedges = iWShape->getEdgeList();
	//------------------------------
	for (vector<WEdge*>::iterator we = wedges.begin(), weend = wedges.end(); we != weend; we++) {
		wxe = dynamic_cast<WXEdge*>(*we);
		if (Nature::NO_FEATURE == wxe->nature())
			continue;

		if (!stopSharpViewEdge(wxe)) {
			bool b = true;
			if (wxe->order() == -1)
				b = false;
			BuildSharpViewEdge(OWXEdge(wxe, b));
		}
	}

	// Reset all userdata for WXEdge structure
	//----------------------------------------
	iWShape->ResetUserData();

	// Add all these new edges to the scene's feature edges list:
	//-----------------------------------------------------------
	vector<FEdge*>& newedges = _pCurrentSShape->getEdgeList();
	vector<SVertex*>& newVertices = _pCurrentSShape->getVertexList();
	vector<ViewVertex*>& newVVertices = _pCurrentVShape->vertices();
	vector<ViewEdge*>& newVEdges = _pCurrentVShape->edges();

	// inserts in ioFEdges, at its end, all the edges of newedges
	ioFEdges.insert(ioFEdges.end(), newedges.begin(), newedges.end());
	ioSVertices.insert(ioSVertices.end(), newVertices.begin(), newVertices.end());
	ioVVertices.insert(ioVVertices.end(), newVVertices.begin(), newVVertices.end());
	ioVEdges.insert(ioVEdges.end(), newVEdges.begin(), newVEdges.end());
}

ViewEdge *ViewEdgeXBuilder::BuildSmoothViewEdge(const OWXFaceLayer& iFaceLayer)
{
	// Find first edge:
	OWXFaceLayer first = iFaceLayer;
	OWXFaceLayer currentFace = first;

	// bidirectional chaining.
	// first direction
	list<OWXFaceLayer> facesChain;
	unsigned size = 0;
	while (!stopSmoothViewEdge(currentFace.fl)) {
		facesChain.push_back(currentFace);
		++size;
		currentFace.fl->userdata = (void *)1; // processed
		// Find the next edge!
		currentFace = FindNextFaceLayer(currentFace);
	}
	OWXFaceLayer end = facesChain.back();
	// second direction
	currentFace = FindPreviousFaceLayer(first);
	while (!stopSmoothViewEdge(currentFace.fl)) {
		facesChain.push_front(currentFace);
		++size;
		currentFace.fl->userdata = (void *)1; // processed
		// Find the previous edge!
		currentFace = FindPreviousFaceLayer(currentFace);
	}
	first = facesChain.front();

	if (iFaceLayer.fl->nature() & Nature::RIDGE) {
		if (size < 4) {
			return 0;
		}
	}

	// Start a new chain edges
	ViewEdge *newVEdge = new ViewEdge;
	newVEdge->setId(_currentViewId);
	++_currentViewId;

	_pCurrentVShape->AddEdge(newVEdge);

	// build FEdges
	FEdge *feprevious = NULL;
	FEdge *fefirst = NULL;
	FEdge *fe = NULL;
	for (list<OWXFaceLayer>::iterator fl = facesChain.begin(), flend = facesChain.end(); fl != flend; ++fl) {
		fe = BuildSmoothFEdge(feprevious, (*fl));
		if (feprevious && fe == feprevious)
			continue;
		fe->setViewEdge(newVEdge);
		if (!fefirst)
			fefirst = fe;
		feprevious = fe;
	}
	// Store the chain starting edge:
	_pCurrentSShape->AddChain(fefirst);
	newVEdge->setNature(iFaceLayer.fl->nature());
	newVEdge->setFEdgeA(fefirst);
	newVEdge->setFEdgeB(fe);

	// is it a closed loop ?
	if ((first == end) && (size != 1)) {
		fefirst->setPreviousEdge(fe);
		fe->setNextEdge(fefirst);
		newVEdge->setA(0);
		newVEdge->setB(0);
	}
	else {
		ViewVertex *vva = MakeViewVertex(fefirst->vertexA());
		ViewVertex *vvb = MakeViewVertex(fe->vertexB());

		((NonTVertex *)vva)->AddOutgoingViewEdge(newVEdge);
		((NonTVertex *)vvb)->AddIncomingViewEdge(newVEdge);

		newVEdge->setA(vva);
		newVEdge->setB(vvb);
	}

	return newVEdge;
}

ViewEdge *ViewEdgeXBuilder::BuildSharpViewEdge(const OWXEdge& iWEdge)
{
	// Start a new sharp chain edges
	ViewEdge *newVEdge = new ViewEdge;
	newVEdge->setId(_currentViewId);
	++_currentViewId;
	unsigned size = 0;

	_pCurrentVShape->AddEdge(newVEdge);

	// Find first edge:
	OWXEdge firstWEdge = iWEdge;
	/* OWXEdge previousWEdge = firstWEdge; */ /* UNUSED */
	OWXEdge currentWEdge = firstWEdge;
	list<OWXEdge> edgesChain;
#if 0 /* TK 02-Sep-2012 Experimental fix for incorrect view edge visibility. */
	// bidirectional chaining
	// first direction:
	while (!stopSharpViewEdge(currentWEdge.e)) {
		edgesChain.push_back(currentWEdge);
		++size;
		currentWEdge.e->userdata = (void *)1; // processed
		// Find the next edge!
		currentWEdge = FindNextWEdge(currentWEdge);
	}
	OWXEdge endWEdge = edgesChain.back();
	// second direction
	currentWEdge = FindPreviousWEdge(firstWEdge);
	while (!stopSharpViewEdge(currentWEdge.e)) {
		edgesChain.push_front(currentWEdge);
		++size;
		currentWEdge.e->userdata = (void *)1; // processed
		// Find the previous edge!
		currentWEdge = FindPreviousWEdge(currentWEdge);
	}
#else
	edgesChain.push_back(currentWEdge);
	++size;
	currentWEdge.e->userdata = (void *)1; // processed
	OWXEdge endWEdge = edgesChain.back();
#endif
	firstWEdge = edgesChain.front();

	// build FEdges
	FEdge *feprevious = NULL;
	FEdge *fefirst = NULL;
	FEdge *fe = NULL;
	for (list<OWXEdge>::iterator we = edgesChain.begin(), weend = edgesChain.end(); we != weend; ++we) {
		fe = BuildSharpFEdge(feprevious, (*we));
		fe->setViewEdge(newVEdge);
		if (!fefirst)
			fefirst = fe;
		feprevious = fe;
	}
	// Store the chain starting edge:
	_pCurrentSShape->AddChain(fefirst);
	newVEdge->setNature(iWEdge.e->nature());
	newVEdge->setFEdgeA(fefirst);
	newVEdge->setFEdgeB(fe);

	// is it a closed loop ?
	if ((firstWEdge == endWEdge) && (size != 1)) {
		fefirst->setPreviousEdge(fe);
		fe->setNextEdge(fefirst);
		newVEdge->setA(0);
		newVEdge->setB(0);
	}
	else {
		ViewVertex *vva = MakeViewVertex(fefirst->vertexA());
		ViewVertex *vvb = MakeViewVertex(fe->vertexB());

		((NonTVertex *)vva)->AddOutgoingViewEdge(newVEdge);
		((NonTVertex *)vvb)->AddIncomingViewEdge(newVEdge);

		newVEdge->setA(vva);
		newVEdge->setB(vvb);
	}

	return newVEdge;
}

OWXFaceLayer ViewEdgeXBuilder::FindNextFaceLayer(const OWXFaceLayer& iFaceLayer)
{
	WXFace *nextFace = NULL;
	WOEdge *woeend;
	real tend;
	if (iFaceLayer.order) {
		woeend = iFaceLayer.fl->getSmoothEdge()->woeb();
		tend = iFaceLayer.fl->getSmoothEdge()->tb();
	}
	else {
		woeend = iFaceLayer.fl->getSmoothEdge()->woea();
		tend = iFaceLayer.fl->getSmoothEdge()->ta();
	}
	// special case of EDGE_VERTEX config:
	if ((tend == 0.0) || (tend == 1.0)) {
		WVertex *nextVertex;
		if (tend == 0.0)
			nextVertex = woeend->GetaVertex();
		else
			nextVertex = woeend->GetbVertex();
		if (nextVertex->isBoundary()) // if it's a non-manifold vertex -> ignore
			return OWXFaceLayer(0, true);
		bool found = false;
		WVertex::face_iterator f = nextVertex->faces_begin();
		WVertex::face_iterator fend = nextVertex->faces_end();
		while ((!found) && (f != fend)) {
			nextFace = dynamic_cast<WXFace*>(*f);
			if ((0 != nextFace) && (nextFace != iFaceLayer.fl->getFace())) {
				vector<WXFaceLayer*> sameNatureLayers;
				nextFace->retrieveSmoothEdgesLayers(iFaceLayer.fl->nature(), sameNatureLayers);
				// don't know... Maybe should test whether this face has also a vertex_edge configuration.
				if (sameNatureLayers.size() == 1) {
					WXFaceLayer *winner = sameNatureLayers[0];
					// check face mark continuity
					if (winner->getFace()->GetMark() != iFaceLayer.fl->getFace()->GetMark())
						return OWXFaceLayer(NULL, true);
					if (woeend == winner->getSmoothEdge()->woea()->twin())
						return OWXFaceLayer(winner, true);
					else
						return OWXFaceLayer(winner, false);
				}
			}
			++f;
		}
	}
	else {
		nextFace = dynamic_cast<WXFace*>(iFaceLayer.fl->getFace()->GetBordingFace(woeend));
		if (!nextFace)
			return OWXFaceLayer(NULL, true);
		// if the next face layer has either no smooth edge or no smooth edge of same nature, no next face
		if (!nextFace->hasSmoothEdges())
			return OWXFaceLayer(NULL, true);
		vector<WXFaceLayer*> sameNatureLayers;
		nextFace->retrieveSmoothEdgesLayers(iFaceLayer.fl->nature(), sameNatureLayers);
		// don't know how to deal with several edges of same nature on a single face
		if ((sameNatureLayers.empty()) || (sameNatureLayers.size() != 1)) {
			return OWXFaceLayer(NULL, true);
		}
		else {
			WXFaceLayer *winner = sameNatureLayers[0];
			// check face mark continuity
			if (winner->getFace()->GetMark() != iFaceLayer.fl->getFace()->GetMark())
				return OWXFaceLayer(NULL, true);
			if (woeend == winner->getSmoothEdge()->woea()->twin())
				return OWXFaceLayer(winner, true);
			else
				return OWXFaceLayer(winner, false);
		}
	}
	return OWXFaceLayer(NULL, true);
}

OWXFaceLayer ViewEdgeXBuilder::FindPreviousFaceLayer(const OWXFaceLayer& iFaceLayer)
{
	WXFace *previousFace = NULL;
	WOEdge *woebegin;
	real tend;
	if (iFaceLayer.order) {
		woebegin = iFaceLayer.fl->getSmoothEdge()->woea();
		tend = iFaceLayer.fl->getSmoothEdge()->ta();
	}
	else {
		woebegin = iFaceLayer.fl->getSmoothEdge()->woeb();
		tend = iFaceLayer.fl->getSmoothEdge()->tb();
	}

	// special case of EDGE_VERTEX config:
	if ((tend == 0.0) || (tend == 1.0)) {
		WVertex *previousVertex;
		if (tend == 0.0)
			previousVertex = woebegin->GetaVertex();
		else
			previousVertex = woebegin->GetbVertex();
		if (previousVertex->isBoundary()) // if it's a non-manifold vertex -> ignore
			return OWXFaceLayer(NULL, true);
		bool found = false;
		WVertex::face_iterator f = previousVertex->faces_begin();
		WVertex::face_iterator fend = previousVertex->faces_end();
		for (; (!found) && (f != fend); ++f) {
			previousFace = dynamic_cast<WXFace*>(*f);
			if ((0 != previousFace) && (previousFace != iFaceLayer.fl->getFace())) {
				vector<WXFaceLayer*> sameNatureLayers;
				previousFace->retrieveSmoothEdgesLayers(iFaceLayer.fl->nature(), sameNatureLayers);
				// don't know... Maybe should test whether this face has also a vertex_edge configuration
				if (sameNatureLayers.size() == 1) {
					WXFaceLayer *winner = sameNatureLayers[0];
					// check face mark continuity
					if (winner->getFace()->GetMark() != iFaceLayer.fl->getFace()->GetMark())
						return OWXFaceLayer(NULL, true);
					if (woebegin == winner->getSmoothEdge()->woeb()->twin())
						return OWXFaceLayer(winner, true);
					else
						return OWXFaceLayer(winner, false);
				}
			}
		}
	}
	else {
		previousFace = dynamic_cast<WXFace*>(iFaceLayer.fl->getFace()->GetBordingFace(woebegin));
		if (0 == previousFace)
			return OWXFaceLayer(NULL, true);
		// if the next face layer has either no smooth edge or no smooth edge of same nature, no next face
		if (!previousFace->hasSmoothEdges())
			return OWXFaceLayer(NULL, true);
		vector<WXFaceLayer*> sameNatureLayers;
		previousFace->retrieveSmoothEdgesLayers(iFaceLayer.fl->nature(), sameNatureLayers);
		// don't know how to deal with several edges of same nature on a single face
		if ((sameNatureLayers.empty()) || (sameNatureLayers.size() != 1)) {
			return OWXFaceLayer(NULL, true);
		}
		else {
			WXFaceLayer *winner = sameNatureLayers[0];
			// check face mark continuity
			if (winner->getFace()->GetMark() != iFaceLayer.fl->getFace()->GetMark())
				return OWXFaceLayer(NULL, true);
			if (woebegin == winner->getSmoothEdge()->woeb()->twin())
				return OWXFaceLayer(winner, true);
			else
				return OWXFaceLayer(winner, false);
		}
	}
	return OWXFaceLayer(NULL, true);
}

FEdge *ViewEdgeXBuilder::BuildSmoothFEdge(FEdge *feprevious, const OWXFaceLayer& ifl)
{
	WOEdge *woea, *woeb;
	real ta, tb;
	SVertex *va, *vb;
	FEdgeSmooth *fe;
	// retrieve exact silhouette data
	WXSmoothEdge *se = ifl.fl->getSmoothEdge();

	if (ifl.order) {
		woea = se->woea();
		woeb = se->woeb();
		ta = se->ta();
		tb = se->tb();
	}
	else {
		woea = se->woeb();
		woeb = se->woea();
		ta = se->tb();
		tb = se->ta();
	}

	Vec3r normal;
	// Make the 2 Svertices
	if (feprevious == 0) { // that means that we don't have any vertex already built for that face
		Vec3r A1(woea->GetaVertex()->GetVertex());
		Vec3r A2(woea->GetbVertex()->GetVertex());
		Vec3r A(A1 + ta * (A2 - A1));

		va = MakeSVertex(A, false);
		// Set normal:
		Vec3r NA1(ifl.fl->getFace()->GetVertexNormal(woea->GetaVertex()));
		Vec3r NA2(ifl.fl->getFace()->GetVertexNormal(woea->GetbVertex()));
		Vec3r na((1 - ta) * NA1 + ta * NA2);
		na.normalize();
		va->AddNormal(na);
		normal = na;

		// Set CurvatureInfo
		CurvatureInfo *curvature_info_a =
		        new CurvatureInfo(*(dynamic_cast<WXVertex*>(woea->GetaVertex())->curvatures()),
		                          *(dynamic_cast<WXVertex*>(woea->GetbVertex())->curvatures()), ta);
		va->setCurvatureInfo(curvature_info_a);
	}
	else {
		va = feprevious->vertexB();
	}

	Vec3r B1(woeb->GetaVertex()->GetVertex());
	Vec3r B2(woeb->GetbVertex()->GetVertex());
	Vec3r B(B1 + tb * (B2 - B1));

	if (feprevious && (B - va->point3D()).norm() < 1.0e-6)
		return feprevious;

	vb = MakeSVertex(B, false);
	// Set normal:
	Vec3r NB1(ifl.fl->getFace()->GetVertexNormal(woeb->GetaVertex()));
	Vec3r NB2(ifl.fl->getFace()->GetVertexNormal(woeb->GetbVertex()));
	Vec3r nb((1 - tb) * NB1 + tb * NB2);
	nb.normalize();
	normal += nb;
	vb->AddNormal(nb);

	// Set CurvatureInfo
	CurvatureInfo *curvature_info_b =
	        new CurvatureInfo(*(dynamic_cast<WXVertex*>(woeb->GetaVertex())->curvatures()),
	                          *(dynamic_cast<WXVertex*>(woeb->GetbVertex())->curvatures()), tb);
	vb->setCurvatureInfo(curvature_info_b);

	// Creates the corresponding feature edge
	fe = new FEdgeSmooth(va, vb);
	fe->setNature(ifl.fl->nature());
	fe->setId(_currentFId);
	fe->setFrsMaterialIndex(ifl.fl->getFace()->frs_materialIndex());
	fe->setFace(ifl.fl->getFace());
	fe->setFaceMark(ifl.fl->getFace()->GetMark());
	if (feprevious == 0)
		normal.normalize();
	fe->setNormal(normal);
	fe->setPreviousEdge(feprevious);
	if (feprevious)
		feprevious->setNextEdge(fe);
	_pCurrentSShape->AddEdge(fe);
	va->AddFEdge(fe);
	vb->AddFEdge(fe);

	++_currentFId;
	ifl.fl->userdata = fe;
	return fe;
}

bool ViewEdgeXBuilder::stopSmoothViewEdge(WXFaceLayer *iFaceLayer)
{
	if (NULL == iFaceLayer)
		return true;
	if (iFaceLayer->userdata == 0)
		return false;
	return true;
}

int ViewEdgeXBuilder::retrieveFaceMarks(WXEdge *iEdge)
{
	WFace *aFace = iEdge->GetaFace();
	WFace *bFace = iEdge->GetbFace();
	int result = 0;
	if (aFace && aFace->GetMark())
		result += 1;
	if (bFace && bFace->GetMark())
		result += 2;
	return result;
}

OWXEdge ViewEdgeXBuilder::FindNextWEdge(const OWXEdge& iEdge)
{
	if (Nature::NO_FEATURE == iEdge.e->nature())
		return OWXEdge(NULL, true);

	WVertex *v;
	if (true == iEdge.order)
		v = iEdge.e->GetbVertex();
	else
		v = iEdge.e->GetaVertex();

	if (((WXVertex *)v)->isFeature())
		return 0; /* XXX eeek? NULL? OWXEdge(NULL, true/false)?*/

	int faceMarks = retrieveFaceMarks(iEdge.e);
	vector<WEdge*>& vEdges = (v)->GetEdges();
	for (vector<WEdge*>::iterator ve = vEdges.begin(), veend = vEdges.end(); ve != veend; ve++) {
		WXEdge *wxe = dynamic_cast<WXEdge*>(*ve);
		if (wxe == iEdge.e)
			continue; // same edge as the one processed

		if (wxe->nature() != iEdge.e->nature())
			continue;

		// check face mark continuity
		if (retrieveFaceMarks(wxe) != faceMarks)
			continue;

		if (wxe->GetaVertex() == v) {
			// That means that the face necesarily lies on the edge left.
			// So the vertex order is OK.
			return OWXEdge(wxe, true);
		}
		else {
			// That means that the face necesarily lies on the edge left.
			// So the vertex order is OK.
			return OWXEdge(wxe, false);
		}
	}
	// we did not find:
	return OWXEdge(NULL, true);
}

OWXEdge ViewEdgeXBuilder::FindPreviousWEdge(const OWXEdge& iEdge)
{
	if (Nature::NO_FEATURE == iEdge.e->nature())
		return OWXEdge(NULL, true);

	WVertex *v;
	if (true == iEdge.order)
		v = iEdge.e->GetaVertex();
	else
		v = iEdge.e->GetbVertex();

	if (((WXVertex *)v)->isFeature())
		return 0;

	int faceMarks = retrieveFaceMarks(iEdge.e);
	vector<WEdge *>& vEdges = (v)->GetEdges();
	for (vector<WEdge *>::iterator ve = vEdges.begin(), veend = vEdges.end(); ve != veend; ve++) {
		WXEdge *wxe = dynamic_cast<WXEdge *>(*ve);
		if (wxe == iEdge.e)
			continue; // same edge as the one processed

		if (wxe->nature() != iEdge.e->nature())
			continue;

		// check face mark continuity
		if (retrieveFaceMarks(wxe) != faceMarks)
			continue;

		if (wxe->GetbVertex() == v) {
			return OWXEdge(wxe, true);
		}
		else {
			return OWXEdge(wxe, false);
		}
	}
	// we did not find:
	return OWXEdge(NULL, true);
}

FEdge *ViewEdgeXBuilder::BuildSharpFEdge(FEdge *feprevious, const OWXEdge& iwe)
{
	SVertex *va, *vb;
	FEdgeSharp *fe;
	Vec3r vA, vB;
	if (iwe.order) {
		vA = iwe.e->GetaVertex()->GetVertex();
		vB = iwe.e->GetbVertex()->GetVertex();
	}
	else {
		vA = iwe.e->GetbVertex()->GetVertex();
		vB = iwe.e->GetaVertex()->GetVertex();
	}
	// Make the 2 SVertex
	va = MakeSVertex(vA, true);
	vb = MakeSVertex(vB, true);

	// get the faces normals and the material indices
	Vec3r normalA, normalB;
	unsigned matA(0), matB(0);
	bool faceMarkA = false, faceMarkB = false;
	if (iwe.order) {
		normalB = (iwe.e->GetbFace()->GetNormal());
		matB = (iwe.e->GetbFace()->frs_materialIndex());
		faceMarkB = (iwe.e->GetbFace()->GetMark());
		if (!(iwe.e->nature() & Nature::BORDER)) {
			normalA = (iwe.e->GetaFace()->GetNormal());
			matA = (iwe.e->GetaFace()->frs_materialIndex());
			faceMarkA = (iwe.e->GetaFace()->GetMark());
		}
	}
	else {
		normalA = (iwe.e->GetbFace()->GetNormal());
		matA = (iwe.e->GetbFace()->frs_materialIndex());
		faceMarkA = (iwe.e->GetbFace()->GetMark());
		if (!(iwe.e->nature() & Nature::BORDER)) {
			normalB = (iwe.e->GetaFace()->GetNormal());
			matB = (iwe.e->GetaFace()->frs_materialIndex());
			faceMarkB = (iwe.e->GetaFace()->GetMark());
		}
	}
	// Creates the corresponding feature edge
	fe = new FEdgeSharp(va, vb);
	fe->setNature(iwe.e->nature());
	fe->setId(_currentFId);
	fe->setaFrsMaterialIndex(matA);
	fe->setbFrsMaterialIndex(matB);
	fe->setaFaceMark(faceMarkA);
	fe->setbFaceMark(faceMarkB);
	fe->setNormalA(normalA);
	fe->setNormalB(normalB);
	fe->setPreviousEdge(feprevious);
	if (feprevious)
		feprevious->setNextEdge(fe);
	_pCurrentSShape->AddEdge(fe);
	va->AddFEdge(fe);
	vb->AddFEdge(fe);
	//Add normals:
	va->AddNormal(normalA);
	va->AddNormal(normalB);
	vb->AddNormal(normalA);
	vb->AddNormal(normalB);

	++_currentFId;
	iwe.e->userdata = fe;
	return fe;
}

bool ViewEdgeXBuilder::stopSharpViewEdge(WXEdge *iEdge)
{
	if (NULL == iEdge)
		return true;
	if (iEdge->userdata == 0)
		return false;
	return true;
}

SVertex *ViewEdgeXBuilder::MakeSVertex(Vec3r& iPoint)
{
	SVertex *va = new SVertex(iPoint, _currentSVertexId);
	SilhouetteGeomEngine::ProjectSilhouette(va);
	++_currentSVertexId;
	// Add the svertex to the SShape svertex list:
	_pCurrentSShape->AddNewVertex(va);
	return va;
}

SVertex *ViewEdgeXBuilder::MakeSVertex(Vec3r& iPoint, bool shared)
{
	SVertex *va;
	if (!shared) {
		va = MakeSVertex(iPoint);
	}
	else {
		// Check whether the iPoint is already in the table
		SVertexMap::const_iterator found = _SVertexMap.find(iPoint);
		if (shared && found != _SVertexMap.end()) {
			va = (*found).second;
		}
		else {
			va = MakeSVertex(iPoint);
			// Add the svertex into the table using iPoint as the key
			_SVertexMap[iPoint] = va;
		}
	}
	return va;
}

ViewVertex *ViewEdgeXBuilder::MakeViewVertex(SVertex *iSVertex)
{
	ViewVertex *vva = iSVertex->viewvertex();
	if (vva)
		return vva;
	vva = new NonTVertex(iSVertex);
	// Add the view vertex to the ViewShape svertex list:
	_pCurrentVShape->AddVertex(vva);
	return vva;
}

} /* namespace Freestyle */