From cfdf4640527de775167e187859f8159227193700 Mon Sep 17 00:00:00 2001 From: Vadim Pisarevsky Date: Tue, 9 Aug 2011 15:11:32 +0000 Subject: [PATCH] initial (buggy) C++ version of Delaunay triangulation --- samples/cpp/delaunay2.cpp | 955 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 955 insertions(+) create mode 100644 samples/cpp/delaunay2.cpp diff --git a/samples/cpp/delaunay2.cpp b/samples/cpp/delaunay2.cpp new file mode 100644 index 0000000000..4bf9f341af --- /dev/null +++ b/samples/cpp/delaunay2.cpp @@ -0,0 +1,955 @@ +#include +#include + +namespace cv +{ + +class CV_EXPORTS_W Subdiv2D +{ +public: + + enum + { + PTLOC_ERROR = -2, + PTLOC_OUTSIDE_RECT = -1, + PTLOC_INSIDE = 0, + PTLOC_VERTEX = 1, + PTLOC_ON_EDGE = 2 + }; + + enum + { + NEXT_AROUND_ORG = 0x00, + NEXT_AROUND_DST = 0x22, + PREV_AROUND_ORG = 0x11, + PREV_AROUND_DST = 0x33, + NEXT_AROUND_LEFT = 0x13, + NEXT_AROUND_RIGHT = 0x31, + PREV_AROUND_LEFT = 0x20, + PREV_AROUND_RIGHT = 0x02 + }; + + CV_WRAP Subdiv2D(); + CV_WRAP Subdiv2D(Rect rect); + CV_WRAP void initDelaunay(Rect rect); + + CV_WRAP int insert(Point2f pt); + CV_WRAP void insert(const vector& ptvec); + CV_WRAP int locate(Point2f pt, CV_OUT int& edge, CV_OUT int& vertex); + + CV_WRAP int findNearest(Point2f pt, CV_OUT Point2f* nearestPt=0); + CV_WRAP void getTriangleList(CV_OUT vector& triangleList); + CV_WRAP void getVoronoiFacetList(const vector& idx, CV_OUT vector >& facetList); + + CV_WRAP Point2f getVertex(int vertex, CV_OUT int* firstEdge=0) const; + + CV_WRAP int getEdge( int edge, int nextEdgeType ) const; + CV_WRAP int nextEdge(int edge) const; + CV_WRAP int rotateEdge(int edge, int rotate) const; + CV_WRAP int symEdge(int edge) const; + CV_WRAP int edgeOrg(int edge, CV_OUT Point2f* orgpt=0) const; + CV_WRAP int edgeDst(int edge, CV_OUT Point2f* dstpt=0) const; + +protected: + int newEdge(); + void deleteEdge(int edge); + int newPoint(Point2f pt, bool isvirtual, int firstEdge=0); + void deletePoint(int vtx); + void setEdgePoints( int edge, int orgPt, int dstPt ); + void splice( int edgeA, int edgeB ); + int connectEdges( int edgeA, int edgeB ); + void swapEdges( int edge ); + int isRightOf(Point2f pt, int edge) const; + void calcVoronoi(); + void clearVoronoi(); + + struct CV_EXPORTS Vertex + { + Vertex(); + Vertex(Point2f pt, bool _isvirtual, int _firstEdge=0); + bool isvirtual() const; + bool isfree() const; + int firstEdge; + int type; + Point2f pt; + }; + struct CV_EXPORTS QuadEdge + { + QuadEdge(); + QuadEdge(int edgeidx); + bool isfree() const; + int next[4]; + int pt[4]; + }; + + vector vtx; + vector qedges; + int freeQEdge; + int freePoint; + bool validGeometry; + + int recentEdge; + Point2f topLeft; + Point2f bottomRight; +}; + + +int Subdiv2D::nextEdge(int edge) const +{ + CV_DbgAssert((size_t)(edge >> 2) < qedges.size()); + return qedges[edge >> 2].next[edge & 3]; +} + +int Subdiv2D::rotateEdge(int edge, int rotate) const +{ + CV_DbgAssert((size_t)(edge >> 2) < qedges.size()); + return (edge & ~3) + ((edge + rotate) & 3); +} + +int Subdiv2D::symEdge(int edge) const +{ + CV_DbgAssert((size_t)(edge >> 2) < qedges.size()); + return edge ^ 2; +} + +int Subdiv2D::getEdge(int edge, int nextEdgeType) const +{ + CV_DbgAssert((size_t)(edge >> 2) < qedges.size()); + edge = qedges[edge >> 2].next[(edge + nextEdgeType) & 3]; + return (edge & ~3) + ((edge + (nextEdgeType >> 4)) & 3); +} + +int Subdiv2D::edgeOrg(int edge, CV_OUT Point2f* orgpt) const +{ + CV_DbgAssert((size_t)(edge >> 2) < qedges.size()); + int vidx = qedges[edge >> 2].pt[edge & 3]; + if( orgpt ) + { + CV_DbgAssert((size_t)vidx < vtx.size()); + *orgpt = vtx[vidx].pt; + } + return vidx; +} + +int Subdiv2D::edgeDst(int edge, CV_OUT Point2f* dstpt) const +{ + CV_DbgAssert((size_t)(edge >> 2) < qedges.size()); + int vidx = qedges[edge >> 2].pt[(edge + 2) & 3]; + if( dstpt ) + { + CV_DbgAssert((size_t)vidx < vtx.size()); + *dstpt = vtx[vidx].pt; + } + return vidx; +} + + +Point2f Subdiv2D::getVertex(int vertex, CV_OUT int* firstEdge) const +{ + CV_DbgAssert((size_t)vertex < vtx.size()); + if( firstEdge ) + *firstEdge = vtx[vertex].firstEdge; + return vtx[vertex].pt; +} + + +Subdiv2D::Subdiv2D() +{ + validGeometry = false; + freeQEdge = 0; + freePoint = 0; + recentEdge = 0; +} + +Subdiv2D::Subdiv2D(Rect rect) +{ + validGeometry = false; + freeQEdge = 0; + freePoint = 0; + recentEdge = 0; + + initDelaunay(rect); +} + + +Subdiv2D::QuadEdge::QuadEdge() +{ + next[0] = next[1] = next[2] = next[3] = 0; + pt[0] = pt[1] = pt[2] = pt[3] = 0; +} + +Subdiv2D::QuadEdge::QuadEdge(int edgeidx) +{ + next[0] = edgeidx; + next[1] = edgeidx+3; + next[2] = edgeidx+2; + next[3] = edgeidx+1; + + pt[0] = pt[1] = pt[2] = pt[3] = 0; +} + +bool Subdiv2D::QuadEdge::isfree() const +{ + return next[0] <= 0; +} + +Subdiv2D::Vertex::Vertex() +{ + firstEdge = 0; + type = -1; +} + +Subdiv2D::Vertex::Vertex(Point2f _pt, bool _isvirtual, int _firstEdge) +{ + firstEdge = _firstEdge; + type = (int)_isvirtual; + pt = _pt; +} + +bool Subdiv2D::Vertex::isvirtual() const +{ + return type > 0; +} + +bool Subdiv2D::Vertex::isfree() const +{ + return firstEdge <= 0; +} + +void Subdiv2D::splice( int edgeA, int edgeB ) +{ + int& a_next = qedges[edgeA >> 2].next[edgeA & 3]; + int& b_next = qedges[edgeB >> 2].next[edgeB & 3]; + int a_rot = rotateEdge(a_next, 1); + int b_rot = rotateEdge(b_next, 1); + int& a_rot_next = qedges[a_rot >> 2].next[a_rot & 3]; + int& b_rot_next = qedges[b_rot >> 2].next[b_rot & 3]; + std::swap(a_next, b_next); + std::swap(a_rot_next, b_rot_next); +} + +void Subdiv2D::setEdgePoints(int edge, int orgPt, int dstPt) +{ + qedges[edge >> 2].pt[edge & 3] = orgPt; + qedges[edge >> 2].pt[(edge + 2) & 3] = dstPt; +} + +int Subdiv2D::connectEdges( int edgeA, int edgeB ) +{ + int edge = newEdge(); + + splice(edge, getEdge(edgeA, NEXT_AROUND_LEFT)); + splice(symEdge(edge), edgeB); + + setEdgePoints(edge, edgeDst(edgeA), edgeOrg(edgeB)); + return edge; +} + +void Subdiv2D::swapEdges( int edge ) +{ + int sedge = symEdge(edge); + int a = getEdge(edge, PREV_AROUND_ORG); + int b = getEdge(sedge, PREV_AROUND_ORG); + + splice(edge, a); + splice(sedge, b); + + setEdgePoints(edge, edgeDst(a), edgeDst(b)); + + splice(edge, getEdge(a, NEXT_AROUND_LEFT)); + splice(sedge, getEdge(b, NEXT_AROUND_LEFT)); +} + +int Subdiv2D::isRightOf(Point2f pt, int edge) const +{ + Point2f org, dst; + edgeOrg(edge, &org); + edgeDst(edge, &dst); + double cw_area = cvTriangleArea( pt, dst, org ); + + return (cw_area > 0) - (cw_area < 0); +} + + +int Subdiv2D::newEdge() +{ + if( freeQEdge == 0 ) + { + qedges.push_back(QuadEdge()); + freeQEdge = (int)(qedges.size()-1); + } + int edge = freeQEdge*4; + freeQEdge = qedges[edge >> 2].next[1]; + qedges[edge >> 2] = QuadEdge(edge); + return edge; +} + +void Subdiv2D::deleteEdge(int edge) +{ + CV_DbgAssert((size_t)(edge >> 2) < (size_t)qedges.size()); + splice( edge, getEdge(edge, PREV_AROUND_ORG) ); + int sedge = symEdge(edge); + splice(sedge, getEdge(sedge, PREV_AROUND_ORG) ); + + edge >>= 2; + qedges[edge].next[0] = -1; + qedges[edge].next[1] = freeQEdge; + freeQEdge = edge; +} + +int Subdiv2D::newPoint(Point2f pt, bool isvirtual, int firstEdge) +{ + if( freePoint == 0 ) + { + vtx.push_back(Vertex()); + freePoint = (int)(vtx.size()-1); + vtx[freePoint].type = -1; + vtx[freePoint].firstEdge = 0; + } + int vidx = freePoint; + freePoint = vtx[vidx].firstEdge; + vtx[vidx] = Vertex(pt, isvirtual, firstEdge); + + return vidx; +} + +void Subdiv2D::deletePoint(int vidx) +{ + CV_DbgAssert( (size_t)vidx < vtx.size() ); + vtx[vidx].firstEdge = freePoint; + vtx[vidx].type = -1; + freePoint = vidx; +} + +int Subdiv2D::locate(Point2f pt, int& _edge, int& _vertex) +{ + int vertex = 0; + + int i, maxEdges = (int)(qedges.size() * 4); + int edge = recentEdge; + + CV_Assert(edge > 0); + + if( pt.x < topLeft.x || pt.y < topLeft.y || pt.x >= bottomRight.x || pt.y >= bottomRight.y ) + CV_Error( CV_StsOutOfRange, "" ); + + int location = PTLOC_ERROR; + + int right_of_curr = isRightOf(pt, edge); + if( right_of_curr > 0 ) + { + edge = symEdge(edge); + right_of_curr = -right_of_curr; + } + + for( i = 0; i < maxEdges; i++ ) + { + int onext_edge = nextEdge( edge ); + int dprev_edge = getEdge( edge, PREV_AROUND_DST ); + + int right_of_onext = isRightOf( pt, onext_edge ); + int right_of_dprev = isRightOf( pt, dprev_edge ); + + if( right_of_dprev > 0 ) + { + if( right_of_onext > 0 || (right_of_onext == 0 && right_of_curr == 0) ) + { + location = PTLOC_INSIDE; + break; + } + else + { + right_of_curr = right_of_onext; + edge = onext_edge; + } + } + else + { + if( right_of_onext > 0 ) + { + if( right_of_dprev == 0 && right_of_curr == 0 ) + { + location = PTLOC_INSIDE; + break; + } + else + { + right_of_curr = right_of_dprev; + edge = dprev_edge; + } + } + else if( right_of_curr == 0 && + isRightOf( vtx[edgeDst(onext_edge)].pt, edge ) >= 0 ) + { + edge = symEdge( edge ); + } + else + { + right_of_curr = right_of_onext; + edge = onext_edge; + } + } + } + + recentEdge = edge; + + if( location == PTLOC_INSIDE ) + { + Point2f org_pt, dst_pt; + edgeOrg(edge, &org_pt); + edgeDst(edge, &dst_pt); + + double t1 = fabs( pt.x - org_pt.x ); + t1 += fabs( pt.y - org_pt.y ); + double t2 = fabs( pt.x - dst_pt.x ); + t2 += fabs( pt.y - dst_pt.y ); + double t3 = fabs( org_pt.x - dst_pt.x ); + t3 += fabs( org_pt.y - dst_pt.y ); + + if( t1 < FLT_EPSILON ) + { + location = PTLOC_VERTEX; + vertex = edgeOrg( edge ); + edge = 0; + } + else if( t2 < FLT_EPSILON ) + { + location = PTLOC_VERTEX; + vertex = edgeDst( edge ); + edge = 0; + } + else if( (t1 < t3 || t2 < t3) && + fabs( cvTriangleArea( pt, org_pt, dst_pt )) < FLT_EPSILON ) + { + location = PTLOC_ON_EDGE; + vertex = 0; + } + } + + if( location == PTLOC_ERROR ) + { + edge = 0; + vertex = 0; + } + + _edge = edge; + _vertex = vertex; + + return location; +} + + +inline bool +isPtInCircle3( Point2f pt, Point2f a, Point2f b, Point2f c) +{ + const double eps = FLT_EPSILON*0.125; + double val = ((double)a.x * a.x + (double)a.y * a.y) * cvTriangleArea( b, c, pt ); + val -= ((double)b.x * b.x + (double)b.y * b.y) * cvTriangleArea( a, c, pt ); + val += ((double)c.x * c.x + (double)c.y * c.y) * cvTriangleArea( a, b, pt ); + val -= ((double)pt.x * pt.x + (double)pt.y * pt.y) * cvTriangleArea( a, b, c ); + + return val > eps ? 1 : val < -eps ? -1 : 0; +} + + +int Subdiv2D::insert(Point2f pt) +{ + int curr_point = 0, curr_edge = 0, deleted_edge = 0; + int location = locate( pt, curr_edge, curr_point ); + + if( location == PTLOC_ERROR ) + CV_Error( CV_StsBadSize, "" ); + + if( location == PTLOC_OUTSIDE_RECT ) + CV_Error( CV_StsOutOfRange, "" ); + + if( location == PTLOC_VERTEX ) + return curr_point; + + if( location == PTLOC_ON_EDGE ) + { + deleted_edge = curr_edge; + recentEdge = curr_edge = getEdge( curr_edge, PREV_AROUND_ORG ); + deleteEdge(deleted_edge); + } + else if( location == PTLOC_INSIDE ) + ; + else + CV_Error_(CV_StsError, ("Subdiv2D::locate returned invalid location = %d", location) ); + + assert( curr_edge != 0 ); + validGeometry = false; + + curr_point = newPoint(pt, false); + int base_edge = newEdge(); + int first_point = edgeOrg(curr_edge); + setEdgePoints(base_edge, first_point, curr_point); + splice(base_edge, curr_edge); + + do + { + base_edge = connectEdges( curr_edge, symEdge(base_edge) ); + curr_edge = getEdge(base_edge, PREV_AROUND_ORG); + } + while( edgeDst(curr_edge) != first_point ); + + curr_edge = getEdge( base_edge, PREV_AROUND_ORG ); + + int i, max_edges = qedges.size()*4; + + for( i = 0; i < max_edges; i++ ) + { + int temp_dst = 0, curr_org = 0, curr_dst = 0; + int temp_edge = getEdge( curr_edge, PREV_AROUND_ORG ); + + temp_dst = edgeDst( temp_edge ); + curr_org = edgeOrg( curr_edge ); + curr_dst = edgeDst( curr_edge ); + + if( isRightOf( vtx[temp_dst].pt, curr_edge ) > 0 && + isPtInCircle3( vtx[curr_org].pt, vtx[temp_dst].pt, + vtx[curr_dst].pt, vtx[curr_point].pt ) < 0 ) + { + swapEdges( curr_edge ); + curr_edge = getEdge( curr_edge, PREV_AROUND_ORG ); + } + else if( curr_org == first_point ) + break; + else + curr_edge = getEdge( nextEdge( curr_edge ), PREV_AROUND_LEFT ); + } + + return curr_point; +} + +void Subdiv2D::insert(const vector& ptvec) +{ + for( size_t i = 0; i < ptvec.size(); i++ ) + insert(ptvec[i]); +} + +void Subdiv2D::initDelaunay( Rect rect ) +{ + float big_coord = 3.f * MAX( rect.width, rect.height ); + float rx = (float)rect.x; + float ry = (float)rect.y; + + vtx.clear(); + qedges.clear(); + + recentEdge = 0; + validGeometry = false; + + topLeft = Point2f( rx, ry ); + bottomRight = Point2f( rx + rect.width, ry + rect.height ); + + Point2f ppA( rx + big_coord, ry ); + Point2f ppB( rx, ry + big_coord ); + Point2f ppC( rx - big_coord, ry - big_coord ); + + vtx.push_back(Vertex()); + qedges.push_back(QuadEdge()); + + freeQEdge = 0; + freePoint = 0; + + int pA = newPoint(ppA, false); + int pB = newPoint(ppB, false); + int pC = newPoint(ppC, false); + + int edge_AB = newEdge(); + int edge_BC = newEdge(); + int edge_CA = newEdge(); + + setEdgePoints( edge_AB, pA, pB ); + setEdgePoints( edge_BC, pB, pC ); + setEdgePoints( edge_CA, pC, pA ); + + splice( edge_AB, symEdge( edge_CA )); + splice( edge_BC, symEdge( edge_AB )); + splice( edge_CA, symEdge( edge_BC )); + + recentEdge = edge_AB; +} + + +void Subdiv2D::clearVoronoi() +{ + size_t i, total = qedges.size(); + + for( i = 0; i < total; i++ ) + qedges[i].pt[1] = qedges[i].pt[3] = 0; + + total = vtx.size(); + for( i = 0; i < total; i++ ) + { + if( vtx[i].isvirtual() ) + deletePoint((int)i); + } + + validGeometry = false; +} + + +static Point2f computeVoronoiPoint(Point2f org0, Point2f dst0, Point2f org1, Point2f dst1) +{ + double a0 = dst0.x - org0.x; + double b0 = dst0.y - org0.y; + double c0 = -0.5*(a0 * (dst0.x + org0.x) + b0 * (dst0.y + org0.y)); + + double a1 = dst1.x - org1.x; + double b1 = dst1.y - org1.y; + double c1 = -0.5*(a1 * (dst1.x + org1.x) + b1 * (dst1.y + org1.y)); + + double det = a0 * b1 - a1 * b0; + + if( det != 0 ) + { + det = 1. / det; + return Point2f((float) ((b0 * c1 - b1 * c0) * det), + (float) ((a1 * c0 - a0 * c1) * det)); + } + + return Point2f(FLT_MAX, FLT_MAX); +} + + +void Subdiv2D::calcVoronoi() +{ + // check if it is already calculated + if( validGeometry ) + return; + + clearVoronoi(); + int i, total = (int)qedges.size(); + + // loop through all quad-edges, except for the first 3 (#1, #2, #3 - 0 is reserved for "NULL" pointer) + for( i = 4; i < total; i++ ) + { + QuadEdge& quadedge = qedges[i]; + + if( quadedge.isfree() ) + continue; + + int edge0 = (int)(i*4); + Point2f org0, dst0, org1, dst1; + + if( !quadedge.pt[3] ) + { + int edge1 = getEdge( edge0, NEXT_AROUND_LEFT ); + int edge2 = getEdge( edge1, NEXT_AROUND_LEFT ); + + edgeOrg(edge0, &org0); + edgeDst(edge0, &dst0); + edgeOrg(edge1, &org1); + edgeDst(edge1, &dst1); + + Point2f virt_point = computeVoronoiPoint(org0, dst0, org1, dst1); + + if( fabs( virt_point.x ) < FLT_MAX * 0.5 && + fabs( virt_point.y ) < FLT_MAX * 0.5 ) + { + quadedge.pt[3] = qedges[edge1 >> 2].pt[3 - (edge1 & 2)] = + qedges[edge2 >> 2].pt[3 - (edge2 & 2)] = newPoint(virt_point, true); + } + } + + if( !quadedge.pt[1] ) + { + int edge1 = getEdge( edge0, NEXT_AROUND_RIGHT ); + int edge2 = getEdge( edge1, NEXT_AROUND_RIGHT ); + + edgeOrg(edge0, &org0); + edgeDst(edge0, &dst0); + edgeOrg(edge1, &org1); + edgeDst(edge1, &dst1); + + Point2f virt_point = computeVoronoiPoint(org0, dst0, org1, dst1); + + if( fabs( virt_point.x ) < FLT_MAX * 0.5 && + fabs( virt_point.y ) < FLT_MAX * 0.5 ) + { + quadedge.pt[1] = qedges[edge1 >> 2].pt[1 + (edge1 & 2)] = + qedges[edge2 >> 2].pt[1 + (edge2 & 2)] = newPoint(virt_point, true); + } + } + } + + validGeometry = true; +} + + +static int +isRightOf2( const Point2f& pt, const Point2f& org, const Point2f& diff ) +{ + double cw_area = ((double)org.x - pt.x)*diff.y - ((double)org.y - pt.y)*diff.x; + return (cw_area > 0) - (cw_area < 0); +} + + +int Subdiv2D::findNearest(Point2f pt, Point2f* nearestPt) +{ + if( !validGeometry ) + calcVoronoi(); + + int vertex = 0, edge = 0; + int loc = locate( pt, edge, vertex ); + + if( loc != PTLOC_ON_EDGE && loc != PTLOC_INSIDE ) + return vertex; + + vertex = 0; + + Point2f start; + edgeOrg(edge, &start); + Point2f diff = pt - start; + + edge = rotateEdge(edge, 1); + + int i, total = (int)vtx.size(); + + for( i = 0; i < total; i++ ) + { + Point2f t; + + for(;;) + { + CV_Assert( edgeDst(edge, &t) > 0 ); + if( isRightOf2( t, start, diff ) >= 0 ) + break; + + edge = getEdge( edge, NEXT_AROUND_LEFT ); + } + + for(;;) + { + CV_Assert( edgeOrg( edge, &t ) > 0 ); + + if( isRightOf2( t, start, diff ) < 0 ) + break; + + edge = getEdge( edge, PREV_AROUND_LEFT ); + } + + Point2f tempDiff; + edgeDst(edge, &tempDiff); + edgeOrg(edge, &t); + tempDiff -= t; + + if( isRightOf2( pt, t, tempDiff ) >= 0 ) + { + vertex = edgeOrg(rotateEdge( edge, 3 )); + break; + } + + edge = symEdge( edge ); + } + + if( nearestPt && vertex > 0 ) + *nearestPt = vtx[vertex].pt; + + return vertex; +} + +void Subdiv2D::getTriangleList(vector& triangleList) +{ + vector processed(vtx.size(), false); + processed[0] = true; + + calcVoronoi(); + triangleList.clear(); + + for( size_t i = 4; i < qedges.size(); i++ ) + { + if( qedges[i].isfree() ) + continue; + int e0 = (int)(i*4), e1 = rotateEdge(e0, 1), e; + int vidx0 = edgeOrg(e1), vidx1 = edgeDst(e1); + Point2f a, b, c; + if( !processed[vidx0] ) + { + edgeOrg(e0, &a); + edgeDst(e0, &b); + e = getEdge(e0, NEXT_AROUND_LEFT); + edgeDst(e, &c); + triangleList.push_back(Vec6f(a.x, a.y, b.x, b.y, c.x, c.y)); + processed[vidx0] = true; + } + if( !processed[vidx1] ) + { + edgeDst(e0, &a); + edgeOrg(e0, &b); + e = getEdge(e0, PREV_AROUND_RIGHT); + edgeOrg(e, &c); + triangleList.push_back(Vec6f(a.x, a.y, b.x, b.y, c.x, c.y)); + processed[vidx1] = true; + } + } +} + +void Subdiv2D::getVoronoiFacetList(const vector& idx, CV_OUT vector >& facetList) +{ + calcVoronoi(); + facetList.clear(); + + vector buf; + + size_t i, total; + if( idx.empty() ) + i = 4, total = vtx.size(); + else + i = 0, total = idx.size(); + + for( ; i < total; i++ ) + { + int k = idx.empty() ? (int)i : idx[i]; + + if( vtx[k].isvirtual() ) + continue; + int edge = rotateEdge(vtx[k].firstEdge, 1), t = edge; + + // gather points + buf.clear(); + do + { + buf.push_back(vtx[edgeOrg(t)].pt); + t = getEdge( t, NEXT_AROUND_LEFT ); + } + while( t != edge ); + + facetList.push_back(buf); + } +} + +} + +using namespace cv; +using namespace std; + +static void help() +{ + cout << "\nThis program demostrates iterative construction of\n" + "delaunay triangulation and voronoi tesselation.\n" + "It draws a random set of points in an image and then delaunay triangulates them.\n" + "Usage: \n" + "./delaunay \n" + "\nThis program builds the traingulation interactively, you may stop this process by\n" + "hitting any key.\n"; +} + + +static void draw_subdiv_point( Mat& img, Point2f fp, Scalar color ) +{ + circle( img, fp, 3, color, CV_FILLED, 8, 0 ); +} + +static void draw_subdiv( Mat& img, Subdiv2D& subdiv, Scalar delaunay_color ) +{ + vector triangleList; + subdiv.getTriangleList(triangleList); + vector pt(3); + + for( size_t i = 0; i < triangleList.size(); i++ ) + { + Vec6f t = triangleList[i]; + pt[0] = Point(cvRound(t[0]), cvRound(t[1])); + pt[1] = Point(cvRound(t[2]), cvRound(t[3])); + pt[2] = Point(cvRound(t[4]), cvRound(t[5])); + line(img, pt[0], pt[1], delaunay_color, 1, CV_AA, 0); + line(img, pt[1], pt[2], delaunay_color, 1, CV_AA, 0); + line(img, pt[2], pt[0], delaunay_color, 1, CV_AA, 0); + } +} + +static void locate_point( Mat& img, Subdiv2D& subdiv, Point2f fp, Scalar active_color ) +{ + int e0=0, vertex=0; + + subdiv.locate(fp, e0, vertex); + + if( e0 > 0 ) + { + int e = e0; + do + { + Point2f org, dst; + if( subdiv.edgeOrg(e, &org) > 0 && subdiv.edgeDst(e, &dst) > 0 ) + line( img, org, dst, active_color, 3, CV_AA, 0 ); + + e = subdiv.getEdge(e, Subdiv2D::NEXT_AROUND_LEFT); + } + while( e != e0 ); + } + + draw_subdiv_point( img, fp, active_color ); +} + + +void paint_voronoi( Mat& img, Subdiv2D& subdiv ) +{ + vector > facets; + subdiv.getVoronoiFacetList(vector(), facets); + + vector ifacet; + vector > ifacets(1); + + for( size_t i = 0; i < facets.size(); i++ ) + { + ifacet.resize(facets[i].size()); + for( size_t j = 0; j < facets[i].size(); j++ ) + ifacet[j] = facets[i][j]; + + Scalar color; + color[0] = rand() & 256; + color[1] = rand() & 256; + color[2] = rand() & 256; + fillConvexPoly(img, ifacet, color, 8, 0); + + ifacets[0] = ifacet; + polylines(img, ifacets, true, Scalar(), 1, CV_AA, 0); + } +} + + +int main( int, char** ) +{ + help(); + + Scalar active_facet_color(0, 0, 255), delaunay_color(255,255,255); + Rect rect(0, 0, 600, 600); + + Subdiv2D subdiv(rect); + Mat img(rect.size(), CV_8UC3); + + img = Scalar::all(0); + string win = "Delaunay Demo"; + imshow(win, img); + + for( int i = 0; i < 200; i++ ) + { + Point2f fp( (float)(rand()%(rect.width-10)+5), + (float)(rand()%(rect.height-10)+5)); + + locate_point( img, subdiv, fp, active_facet_color ); + imshow( win, img ); + + if( waitKey( 100 ) >= 0 ) + break; + + subdiv.insert(fp); + img = Scalar::all(0); + draw_subdiv( img, subdiv, delaunay_color ); + imshow( win, img ); + + if( waitKey( 100 ) >= 0 ) + break; + } + + img = Scalar::all(0); + paint_voronoi( img, subdiv ); + imshow( win, img ); + + waitKey(0); + + return 0; +}