osg::DVRClipGeometry Class Reference

*put brief class description here*

#include <OSGDVRClipGeometry.h>

Inheritance diagram for osg::DVRClipGeometry:

List of all members.

Clipping
*void	buildContours (Real32 dist2RefPlane, bool positiveWinding, const Vec3f &sliceNormal)
	Identifies all contours and links them.
void	linkContour (DVRTriangle *startTriangle, Real32 dist2RefPlane, const Vec3f &viewDir, bool positiveWinding)
	Identifies and links a contour starting with the given triangle.
void	updateActiveTriangles (Real32 dist2RefPlane, const Vec3f &sliceNormal)
	updates the active triangle list
void	addActiveTriangle (DVRTriangle *tri)
	Identifies all contours and links them.
void	addNewActiveTriangles (DVRVertex *vertex, Real32 dist2RefPlane)
	Identifies all contours and links them.
Pnt3f	interpolate (DVRTriangle *tri, Int32 v1, Int32 v2, Real32 dist2RefPlane)
	Identifies all contours and links them.
void	operator= (const DVRClipGeometry &source)
	Identifies all contours and links them.
static void	initMethod (void)
	Identifies all contours and links them.
class	FieldContainer
	Identifies all contours and links them.
class	DVRClipGeometryBase
	Identifies all contours and links them.
Public Types
typedef DVRClipGeometryPtr	Ptr
enum	{ GeometryNodeFieldId = Inherited::NextFieldId, BeaconFieldId = GeometryNodeFieldId + 1, NextFieldId = BeaconFieldId + 1 }
Public Member Functions
Sync
*virtual void	changed (BitVector whichField, UInt32 origin)
Output
*virtual void	dump (UInt32 uiIndent=0, const BitVector bvFlags=0) const
Clipping
*void	initialize (const Matrix &volumeToWorld)
void	resetLocalData (void)
	Reset local data of vertices and triangles.
void	setReferencePlane (const Plane &referencePlane)
	Set the reference plane used in the clipping algorithm.
bool	setNumAddPerVertexAttr (UInt32 additionalPerVertexAttributes)
	set the number of additional per vertex attributes
void	computeSeedVertices (void)
	Compute the seed vertex set.
const DVRTriangleList &	getContours (float dist2RefPlane, bool positiveWinding, const Vec3f &sliceNormal)
	find contour made up by triangles which are cut by the current slice
FieldContainer Get
*virtual FieldContainerType &	getType (void)
virtual const FieldContainerType &	getType (void) const
virtual UInt32	getContainerSize (void) const
Field Get
*SFNodePtr *	getSFGeometryNode (void)
	Get the DVRClipGeometry::_sfGeometryNode field.
SFNodePtr *	getSFBeacon (void)
	Get the DVRClipGeometry::_sfBeacon field.
NodePtr &	getGeometryNode (void)
	Get the value of the DVRClipGeometry::_sfGeometryNode field.
const NodePtr &	getGeometryNode (void) const
	Get the value of the DVRClipGeometry::_sfGeometryNode field.
NodePtr &	getBeacon (void)
	Get the value of the DVRClipGeometry::_sfBeacon field.
const NodePtr &	getBeacon (void) const
	Get the value of the DVRClipGeometry::_sfBeacon field.
Field Set
*void	setGeometryNode (const NodePtr &value)
	Set the value of the DVRClipGeometry::_sfGeometryNode field.
void	setBeacon (const NodePtr &value)
	Set the value of the DVRClipGeometry::_sfBeacon field.
Binary Access
*virtual UInt32	getBinSize (const BitVector &whichField)
virtual void	copyToBin (BinaryDataHandler &pMem, const BitVector &whichField)
virtual void	copyFromBin (BinaryDataHandler &pMem, const BitVector &whichField)
Copy
*virtual FieldContainerPtr	shallowCopy (void) const
Static Public Member Functions
Class Get
*static FieldContainerType &	getClassType (void)
	access the type of the class
static UInt32	getClassTypeId (void)
	access the numerical type of the class
Construction
*static DVRClipGeometryPtr	create (void)
	create a new instance of the class
static DVRClipGeometryPtr	createEmpty (void)
	create an empty new instance of the class, do not copy the prototype
Static Public Attributes
static const osg::BitVector	GeometryNodeFieldMask
static const osg::BitVector	BeaconFieldMask
static const osg::BitVector	MTInfluenceMask
static const BitVector	NextFieldMask
Protected Member Functions
Constructors
*	DVRClipGeometry (void)
	DVRClipGeometry (const DVRClipGeometry &source)
Destructors
*virtual	~DVRClipGeometry (void)
Vertices
*Int32	insertVertex (Int32 idx)
	Insert a vertex in the vertex list.
bool	isLocalMinimum (DVRVertex &vertex)
Triangles
*bool	isCut (DVRTriangle *tri, Real32 dist2RefPlane, DVRVertex *switchedVertices[3])
bool	isBehindPlane (DVRTriangle &tri, Real32 dist2RefPlane)
void	renderTriangle (const DVRTriangle &tri) const
	Use OpenGL to render the triangle.
Triangle Geometry Setup
*bool	buildTriangledGeometry (void)
	create the triangled geometry data structure
Sync
*void	executeSyncImpl (DVRClipGeometryBase *pOther, const BitVector &whichField)
virtual void	executeSync (FieldContainer &other, const BitVector &whichField)
Protected Attributes
Locals
*bool	initialized
	is the clip geometry initialized?
GeometryPtr	geometry
	the core of the geometry node
std::vector< DVRVertex >	_mfVertices
	list of vertices in the triangulated clip geometry
std::vector< DVRTriangle >	_mfTriangles
	list of triangles in the triangulated clip geometry
Matrix	toVolumeSpace
DVRTriangle **	activeTriangles
	the triangles which are cut by the current slice
UInt32	activeTrianglesCount
	is the clip geometry initialized?
UInt32	maxActiveTrianglesCount
	is the clip geometry initialized?
DVRVertex **	seedVertices
	the vertices which are closest to the reference plane
UInt32	seedVerticesCount
	is the clip geometry initialized?
UInt32	maxSeedVerticesCount
	is the clip geometry initialized?
DVRTriangleList	contours
Fields
*SFNodePtr	_sfGeometryNode
SFNodePtr	_sfBeacon
Private Types
typedef DVRClipGeometryBase	Inherited

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Detailed Description

Definition at line 58 of file OSGDVRClipGeometry.h.

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Member Typedef Documentation

typedef DVRClipGeometryBase osg::DVRClipGeometry::Inherited [private]

Reimplemented from osg::DVRClipGeometryBase. Definition at line 62 of file OSGDVRClipGeometry.h.

typedef DVRClipGeometryPtr osg::DVRClipGeometryBase::Ptr [inherited]

Definition at line 91 of file OSGDVRClipGeometryBase.h.

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Member Enumeration Documentation

anonymous enum [inherited]

Enumerator: GeometryNodeFieldId  BeaconFieldId  NextFieldId  Reimplemented from osg::FieldContainer. Definition at line 93 of file OSGDVRClipGeometryBase.h. { GeometryNodeFieldId = Inherited::NextFieldId, BeaconFieldId = GeometryNodeFieldId + 1, NextFieldId = BeaconFieldId + 1 };

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Constructor & Destructor Documentation

DVRClipGeometry::DVRClipGeometry (  void   )  [protected]

Definition at line 65 of file OSGDVRClipGeometry.cpp. References activeTriangles, activeTrianglesCount, initialized, maxActiveTrianglesCount, maxSeedVerticesCount, seedVertices, and seedVerticesCount. : Inherited() { initialized = false; maxActiveTrianglesCount = 4; activeTrianglesCount = 0; maxSeedVerticesCount = 4; seedVerticesCount = 0; activeTriangles = (DVRTriangle **) malloc(maxActiveTrianglesCount * sizeof(DVRTriangle *) ); seedVertices = (DVRVertex **) malloc(maxSeedVerticesCount * sizeof(DVRVertex *) ); }

DVRClipGeometry::DVRClipGeometry (  const DVRClipGeometry &  source  )  [protected]

Definition at line 84 of file OSGDVRClipGeometry.cpp. References activeTriangles, activeTrianglesCount, initialized, maxActiveTrianglesCount, maxSeedVerticesCount, seedVertices, and seedVerticesCount. : Inherited(source) { initialized = false; maxActiveTrianglesCount = 4; activeTrianglesCount = 0; maxSeedVerticesCount = 4; seedVerticesCount = 0; activeTriangles = (DVRTriangle **) malloc(maxActiveTrianglesCount * sizeof(DVRTriangle *) ); seedVertices = (DVRVertex **) malloc(maxSeedVerticesCount * sizeof(DVRVertex *) ); }

DVRClipGeometry::~DVRClipGeometry (  void   )  [protected, virtual]

Definition at line 103 of file OSGDVRClipGeometry.cpp. References activeTriangles, and seedVertices. { if(activeTriangles) free(activeTriangles); // allocation with malloc/realloc!! if(seedVertices) free(seedVertices); // allocation with malloc/realloc!! }

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Member Function Documentation

void DVRClipGeometry::changed (  BitVector  whichField, UInt32  origin )  [virtual]

Reimplemented from osg::FieldContainer. Definition at line 120 of file OSGDVRClipGeometry.cpp. References osg::FieldContainer::changed(), osg::DVRClipGeometryBase::GeometryNodeFieldMask, and initialized. { Inherited::changed(whichField, origin); if ((whichField & GeometryNodeFieldMask)) { initialized = false; } }

void DVRClipGeometry::dump (  UInt32  uiIndent = 0, const BitVector  bvFlags = 0 )  const [virtual]

Implements osg::FieldContainer. Definition at line 131 of file OSGDVRClipGeometry.cpp. References SLOG. { // _sfGeometry.dump(); // _sfBeacon.dump(); SLOG << "Dump DVRClipGeometry NI" << std::endl; }

void DVRClipGeometry::initialize (  const Matrix &  volumeToWorld  )

Prepare the object for clipping a volume's slices (transform it to volume's space) Definition at line 314 of file OSGDVRClipGeometry.cpp. References _mfTriangles, _mfVertices, buildTriangledGeometry(), osg::AttachmentContainerPtr::dcast(), geometry, osg::DVRClipGeometryBase::getBeacon(), osg::NodePtr::getCore(), osg::DVRClipGeometryBase::getGeometryNode(), initialized, osg::TransformationMatrix< ValueTypeT >::inverse(), osg::TransformationMatrix< ValueTypeT >::invert(), osg::TransformationMatrix< ValueTypeT >::mult(), osg::TransformationMatrix< ValueTypeT >::multMatrixPnt(), osg::TransformationMatrix< ValueTypeT >::multMatrixVec(), osg::NullFC, toVolumeSpace, and osg::TransformationMatrix< ValueTypeT >::transpose(). { if(!initialized) { _mfVertices.clear (); _mfTriangles.clear(); if(getGeometryNode() != NullFC) { if(getGeometryNode()->getCore() != NullFC) { geometry = GeometryPtr::dcast(getGeometryNode()->getCore()); if(geometry != NullFC) initialized = buildTriangledGeometry(); } } } if(!initialized) return; Matrix old = toVolumeSpace; toVolumeSpace = volumeToWorld; toVolumeSpace.invert(); NodePtr beacon = getBeacon(); if(beacon != NullFC) { toVolumeSpace.mult(beacon->getToWorld()); } else if(getGeometryNode() != NullFC) { toVolumeSpace.mult(getGeometryNode()->getToWorld()); } Matrix toVolumeSpaceInvT; toVolumeSpace .inverse(toVolumeSpaceInvT); toVolumeSpaceInvT.transpose(); UInt32 numVertices = _mfVertices.size(); // transform vertices to volume's space for(UInt32 i = 0; i < numVertices; i++) { toVolumeSpace.multMatrixPnt(_mfVertices[i].pos, _mfVertices[i].transformedPos); } UInt32 numTriangles = _mfTriangles.size(); // transform triangle normals to volume's space for(UInt32 i = 0; i < numTriangles; i++) { toVolumeSpaceInvT.multMatrixVec(_mfTriangles[i].normal, _mfTriangles[i].transformedNormal); _mfTriangles[i].transformedNormal.normalize(); } }

void DVRClipGeometry::resetLocalData (  void   )

Definition at line 379 of file OSGDVRClipGeometry.cpp. References _mfTriangles, _mfVertices, and osg::DVRVertex::behindPlane. { UInt32 numVertices = _mfVertices.size(); for(UInt32 i = 0; i < numVertices; i++) { DVRVertex &vertex = _mfVertices[i]; vertex.behindPlane = false; } UInt32 numTriangles = _mfTriangles.size(); // initialize the triangles local data for(UInt32 i = 0; i < numTriangles; i++) { _mfTriangles[i].visited = false; _mfTriangles[i].inContour = false; for (UInt32 j = 0; j < 3; j++) _mfTriangles[i].edgeCut[j] = false; } }

void DVRClipGeometry::setReferencePlane (  const Plane &  referencePlane  )

Definition at line 403 of file OSGDVRClipGeometry.cpp. References _mfVertices. { UInt32 numVertices = _mfVertices.size(); for(UInt32 i = 0; i < numVertices; i++) _mfVertices[i].calculatePlaneDistanceTransformed(referencePlane); }

bool DVRClipGeometry::setNumAddPerVertexAttr (  UInt32  additionalPerVertexAttributes  )

basically there are two attributes available, the vertex position and a 3D texture coordinate. If one needs additional attributes, e.g. color, texture coordinates,.., the number of (double) values needed has to be set with this function. Definition at line 776 of file OSGDVRClipGeometry.cpp. References _mfTriangles. { UInt32 numTriangles = _mfTriangles.size(); // update triangles for(UInt32 i = 0; i < numTriangles; i++) { if(!_mfTriangles[i].setNumAddPerVertexAttr( additionalPerVertexAttributes)) { return false; } } return true; }

void DVRClipGeometry::computeSeedVertices (  void   )

Definition at line 411 of file OSGDVRClipGeometry.cpp. References _mfVertices, activeTrianglesCount, initialized, isLocalMinimum(), maxSeedVerticesCount, seedVertices, and seedVerticesCount. { if(!initialized) return; // clear seed vertex list and active triangle list seedVerticesCount = 0; activeTrianglesCount = 0; UInt32 numVertices = _mfVertices.size(); // compute initial seed vertex set for(UInt32 i = 0; i < numVertices; i++) { if(isLocalMinimum(_mfVertices[i])) { if(maxSeedVerticesCount <= seedVerticesCount) { maxSeedVerticesCount *= 2; seedVertices = (DVRVertex **)realloc(seedVertices, maxSeedVerticesCount * sizeof(DVRVertex *) ); } seedVertices[seedVerticesCount++] = &_mfVertices[i]; } } }

const DVRTriangleList & DVRClipGeometry::getContours (  float  dist2RefPlane, bool  positiveWinding, const Vec3f &  sliceNormal )

Definition at line 637 of file OSGDVRClipGeometry.cpp. References buildContours(), contours, initialized, and updateActiveTriangles(). { if(!initialized) return contours; // compute new active triangle set and for this slice // and update seed vertex set updateActiveTriangles(dist2RefPlane, sliceNormal); // build contours from active triangle set buildContours(dist2RefPlane, positiveWinding, sliceNormal); return contours; }

Int32 DVRClipGeometry::insertVertex (  Int32  idx  )  [protected]

if there already exists a vertex at the position of the new vertex they get unified, i.e. the index of the already existent vertex is returned, else a new one is inserted Definition at line 140 of file OSGDVRClipGeometry.cpp. References _mfVertices, geometry, and osg::DVRVertex::pos. Referenced by buildTriangledGeometry(). { for(UInt32 i = 0; i < _mfVertices.size(); i++) { if(_mfVertices[i].pos == geometry->getPositions()->getValue(idx)) return i; } DVRVertex newVertex; newVertex.pos = geometry->getPositions()->getValue(idx); _mfVertices.push_back(newVertex); return _mfVertices.size() - 1; }

bool osg::DVRClipGeometry::isLocalMinimum (  DVRVertex &  vertex  )  [inline, protected]

returns true, iff this vertex is a local minimum with respect to refPlaneDistance. Definition at line 48 of file OSGDVRClipGeometry.inl. References _mfTriangles, _mfVertices, osg::DVRVertex::adjacentTriangles, and osg::DVRVertex::refPlaneDistance. Referenced by computeSeedVertices(). { for(MFInt32::const_iterator triIdx = vertex.adjacentTriangles.begin(); triIdx != vertex.adjacentTriangles.end (); triIdx++) { const Int32 *vertIndices = _mfTriangles[*triIdx].vertices; for(unsigned int j = 0; j < 3; j++) { if (&_mfVertices[vertIndices[j]] != &vertex) { if(_mfVertices[vertIndices[j]].isCloser( vertex.refPlaneDistance)) { return false; } } } } return true; }

bool DVRClipGeometry::isCut (  DVRTriangle *  tri, Real32  dist2RefPlane, DVRVertex *  switchedVertices[3] )  [protected]

returns true, iff the plane with distance dist2RefPlane to the ref plane cuts the triangle. Definition at line 262 of file OSGDVRClipGeometry.cpp. References _mfVertices, osg::DVRTriangle::edgeCut, and osg::DVRTriangle::vertices. Referenced by addNewActiveTriangles(), and updateActiveTriangles(). { bool v[3] = {false, false, false}; bool vertexSwitched; int countSwitchedVertices = 0; switchedVertices[0] = NULL; switchedVertices[1] = NULL; switchedVertices[2] = NULL; // for every vertex, check if it is in front of or behind the current // reference plane and if it has moved behind the plane for(UInt32 i = 0; i < 3; i++) { v[i] = _mfVertices[tri->vertices[i]].isBehindPlane(dist2RefPlane, vertexSwitched); if(vertexSwitched) { vertexSwitched = false; switchedVertices[countSwitchedVertices] = &_mfVertices[tri->vertices[i]]; countSwitchedVertices++; } } bool cut = false; // remember the cut edges for faster (and correct ;-) contour tracing... for(UInt32 i = 0; i < 3; i++) { if(v[i] ^ v[(i + 1) % 3]) { tri->edgeCut[i] = true; cut = true; } else { tri->edgeCut[i] = false; } } return cut; }

bool osg::DVRClipGeometry::isBehindPlane (  DVRTriangle &  tri, Real32  dist2RefPlane )  [inline, protected]

returns true, iff dist2RefPlane is bigger than the distance to the reference plane of all vertices within the triangle. Definition at line 85 of file OSGDVRClipGeometry.inl. References _mfVertices, and osg::DVRTriangle::vertices. { bool switched; bool v[3]; for(unsigned int i = 0; i < 3; i++) { v[i] = _mfVertices[tri.vertices[i]].isBehindPlane(dist2RefPlane,switched); } return (v[0] && v[1] && v[2]); }

void osg::DVRClipGeometry::renderTriangle (  const DVRTriangle &  tri  )  const [inline, protected]

Definition at line 73 of file OSGDVRClipGeometry.inl. References _mfVertices, and osg::DVRTriangle::vertices. { glBegin(GL_TRIANGLES); { for(unsigned int i = 0; i < 3; i++) glVertex3fv( _mfVertices[tri.vertices[i]].transformedPos.getValues()); } glEnd(); }

bool DVRClipGeometry::buildTriangledGeometry (  void   )  [protected]

Definition at line 158 of file OSGDVRClipGeometry.cpp. References _mfTriangles, _mfVertices, osg::DVRVertex::adjacentTriangles, osg::VectorInterface< ValueTypeT, StorageInterfaceT >::cross(), osg::DVRTriangle::cutPnt, osg::DVRTriangle::cutPoint, osg::VectorInterface< ValueTypeT, StorageInterfaceT >::dot(), geometry, osg::TriangleIterator::getNormal(), osg::TriangleIterator::getPositionIndex(), insertVertex(), osg::PointInterface< ValueTypeT, StorageInterfaceT >::negate(), osg::DVRTriangle::normal, osg::VectorInterface< ValueTypeT, StorageInterfaceT >::normalize(), SLOG, and osg::DVRTriangle::vertices. Referenced by initialize(). { // create triangles for(TriangleIterator triangleIt = geometry->beginTriangles(); triangleIt != geometry->endTriangles (); ++triangleIt) { DVRTriangle newTriangle; for(UInt32 i = 0; i < 3; i++) { Int32 vertexIndex = triangleIt.getPositionIndex(i); vertexIndex = insertVertex(vertexIndex); newTriangle.vertices[i] = vertexIndex; _mfVertices[vertexIndex].adjacentTriangles.push_back( _mfTriangles.size()); newTriangle.cutPnt [i] = 0.0; newTriangle.cutPoint[i] = 0.0; } // compute normal and check orientation newTriangle.normal = (_mfVertices[newTriangle.vertices[0]].pos - _mfVertices[newTriangle.vertices[1]].pos).cross( _mfVertices[newTriangle.vertices[0]].pos - _mfVertices[newTriangle.vertices[2]].pos); newTriangle.normal.normalize(); if(newTriangle.normal.dot(triangleIt.getNormal(0)) < 0.0) newTriangle.normal.negate(); _mfTriangles.push_back(newTriangle); } // find neighbouring triangles for(UInt32 i = 0; i < _mfTriangles.size(); i++) { Int32 *vertices = _mfTriangles[i].vertices; for(UInt32 l = 0; l < 3; l++) { const DVRVertex &v0 = _mfVertices[vertices[l]]; const DVRVertex &v1 = _mfVertices[vertices[(l + 1) % 3]]; for(UInt32 j = 0; j < v0.adjacentTriangles.size(); j++) { for(UInt32 k = 0; k < v1.adjacentTriangles.size(); k++) { if(v0.adjacentTriangles[j] == v1.adjacentTriangles[k] && v0.adjacentTriangles[j] != i && v1.adjacentTriangles[k] != i ) { if(_mfTriangles[i].neighbours[l] != -1) { SLOG << "Error: Could not build clip geometry" << std::endl << " one triangle edge shared by more " << "than two triangles" << std::endl; return false; } _mfTriangles[i].neighbours[l] = v1.adjacentTriangles[k]; } } } } } // check for non-closed geometry UInt32 checkCount = 0; for(UInt32 i = 0; i < _mfTriangles.size(); i++) { for(UInt32 j = 0; j < 3; j++) { if(_mfTriangles[i].neighbours[j] == -1) { checkCount++; } } } if(checkCount > 0) { SLOG << "Error: Could not build clip geometry" << std::endl << checkCount << "open edges found!" << std::endl; return false; } return true; }

void DVRClipGeometry::buildContours (  Real32  dist2RefPlane, bool  positiveWinding, const Vec3f &  sliceNormal )  [protected]

Definition at line 614 of file OSGDVRClipGeometry.cpp. References activeTriangles, activeTrianglesCount, contours, osg::DVRTriangle::inContour, and linkContour(). Referenced by getContours(). { contours.clear(); for(UInt32 i = 0; i < activeTrianglesCount; i++) { DVRTriangle* currentTriangle = activeTriangles[i]; // if the triangle is already in a contour we can skip it if(!currentTriangle->inContour) { contours.push_back(currentTriangle); linkContour(currentTriangle, dist2RefPlane, sliceNormal, positiveWinding); } } }

void DVRClipGeometry::linkContour (  DVRTriangle *  startTriangle, Real32  dist2RefPlane, const Vec3f &  viewDir, bool  positiveWinding )  [protected]

Definition at line 442 of file OSGDVRClipGeometry.cpp. References _mfTriangles, osg::DVRTriangle::contourNeighbour, osg::VectorInterface< ValueTypeT, StorageInterfaceT >::cross(), osg::DVRTriangle::cutPnt, osg::DVRTriangle::cutPoint, osg::VectorInterface< ValueTypeT, StorageInterfaceT >::dot(), osg::DVRTriangle::edgeCut, FDEBUG, osg::DVRTriangle::inContour, interpolate(), osg::DVRTriangle::neighbours, and osg::DVRTriangle::transformedNormal. Referenced by buildContours(). { FDEBUG(("DVRClipGeometry - linkcontour dist = %f\n", dist2RefPlane)); bool closed = false; // first, we have to check for the correct winding direction. Pnt3f vertex[2]; bool firstEdge; int first = 0, second = 0; if(startTriangle->edgeCut[0] && startTriangle->edgeCut[1]) { vertex[0] = interpolate(startTriangle, 1, 0, dist2RefPlane); vertex[1] = interpolate(startTriangle, 1, 2, dist2RefPlane); first = 0; second = 1; } else if (startTriangle->edgeCut[1] && startTriangle->edgeCut[2]) { vertex[0] = interpolate(startTriangle, 2, 1, dist2RefPlane); vertex[1] = interpolate(startTriangle, 2, 0, dist2RefPlane); first = 1; second = 2; } else if (startTriangle->edgeCut[0] && startTriangle->edgeCut[2]) { vertex[0] = interpolate(startTriangle, 0, 1, dist2RefPlane); vertex[1] = interpolate(startTriangle, 0, 2, dist2RefPlane); first = 0; second = 2; } // Now we should have both cut points on our edges. // If the cross product of the normal of this triangle with the // vector between the two cut points (cutPoint[1] - cutPoint[0]) // has a positive dot product with the viewing direction, then // the edge with cutPoint[0] on it is the right direction, otherwise // we would have to choose the other direction. Vec3f tmp = vertex[1] - vertex[0]; tmp = tmp.cross(startTriangle->transformedNormal); if(tmp.dot(viewDir) <= 0.0) { firstEdge = false; }else { firstEdge = true; } if(!positiveWinding) firstEdge = !firstEdge; DVRTriangle *current = startTriangle; current->inContour = true; if(firstEdge) { current->cutPnt = vertex[0]; current->cutPoint[0] = vertex[0][0]; current->cutPoint[1] = vertex[0][1]; current->cutPoint[2] = vertex[0][2]; current->contourNeighbour = &_mfTriangles[current->neighbours[first]]; // // debugging -> remove // if(!current->contourNeighbour){ // std::cerr<<"contour neighbour is NULL\n"; // exit(0); // } current = current->contourNeighbour;