QEM三维模型抽稀算法C++Wraper实例
去年研究了QEM算法,下面简要记录下研究过程
一,QEM三维模型简化算法,介绍见
1.QEM(Quadric Error Mactrics,二次误差测度)模型简化算法,具有兼顾执行效率和模型质量的优点(https://www.cnblogs.com/kekec/archive/2011/12/07/2279320.html)
2.C++源码:http://mgarland.org/software/qslim.html
二,Wraper代码实现
新建CLR C++项目“QSlimWraper”,包含Mesh.h,QSlim.h,QSlim.cpp代码
新建Wraper.cpp,实现qslim_init(),qslim_run()函数,见下面
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
1 #include "Mesh.h" 2 #include "QSlim.h" 3 4 5 using namespace System::Runtime::InteropServices; 6 static void qslim_init() 7 { 8 int i; 9 cerr << "Reading input ..." << endl; 10 cerr << "Cleaning up initial input ..." << endl; 11 int initialVertCount = M0.vertCount(); 12 int initialEdgeCount = M0.edgeCount(); 13 int initialFaceCount = M0.faceCount(); 14 for (i = 0; i < M0.faceCount(); i++) 15 if (!M0.face(i)->plane().isValid()) 16 M0.killFace(M0.face(i)); 17 M0.removeDegeneracy(M0.allFaces()); 18 for (i = 0; i < M0.vertCount(); i++) 19 { 20 if (M0.vertex(i)->edgeUses().length() == 0) 21 M0.vertex(i)->kill(); 22 } 23 cerr << "Input model summary:" << endl; 24 cerr << " Vertices : " << initialVertCount << endl; 25 cerr << " Edges : " << initialEdgeCount << endl; 26 int man = 0, non = 0, bndry = 0, bogus = 0; 27 for (i = 0; i < M0.edgeCount(); i++) 28 switch (M0.edge(i)->faceUses().length()) 29 { 30 case 0: 31 bogus++; 32 break; 33 case 1: 34 bndry++; 35 break; 36 case 2: 37 man++; 38 break; 39 default: 40 non++; 41 break; 42 } 43 if (bogus) 44 cerr << " Bogus : " << bogus << endl; 45 cerr << " Boundary : " << bndry << endl; 46 cerr << " Manifold : " << man << endl; 47 cerr << " Nonmanifold : " << non << endl; 48 49 cerr << " Faces : " << initialFaceCount << endl; 50 } 51 52 static void qslim_run() 53 { 54 decimate_init(M0, pair_selection_tolerance); 55 while (M0.validFaceCount > face_target&& decimate_min_error() < error_tolerance) 56 { 57 decimate_contract(M0); 58 } 59 }
新建QSlimWraper namespace,实现CLR,见下面
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
1 namespace QSlimWraper 2 { 3 public ref struct Point3dWrap 4 { 5 float X; 6 float Y; 7 float Z; 8 int R;//red 9 int G;//green 10 int B;//blue 11 Point3dWrap() 12 { 13 X = 0; 14 Y = 0; 15 Z = 0; 16 } 17 ~Point3dWrap() 18 { 19 } 20 Point3dWrap(float x, float y, float z) 21 { 22 this->X = x; 23 this->Y = y; 24 this->Z = z; 25 } 26 Point3dWrap(float x, float y, float z, int r, int g, int b) 27 { 28 this->X = x; 29 this->Y = y; 30 this->Z = z; 31 this->R = r; 32 this->G = g; 33 this->B = b; 34 } 35 }; 36 37 public ref struct TriangleWrap 38 { 39 int pIndex0; 40 int pIndex1; 41 int pIndex2; 42 int R;//red 43 int G;//green 44 int B;//blue 45 46 TriangleWrap() 47 { 48 this->pIndex0 = -1; 49 this->pIndex1 = -1; 50 this->pIndex2 = -1; 51 } 52 ~TriangleWrap() 53 { 54 } 55 TriangleWrap(int p0index, int p1index, int p2index) 56 { 57 this->pIndex0 = p0index; 58 this->pIndex1 = p1index; 59 this->pIndex2 = p2index; 60 } 61 TriangleWrap(int p0index, int p1index, int p2index, int r, int g, int b) 62 { 63 this->pIndex0 = p0index; 64 this->pIndex1 = p1index; 65 this->pIndex2 = p2index; 66 this->R = r; 67 this->G = g; 68 this->B = b; 69 } 70 }; 71 72 public ref class QSlimWrap 73 { 74 public: 75 QSlimWrap(); 76 ~QSlimWrap(); 77 int ReadFile(char* file); 78 int OutputFile(char* newFile); 79 80 int InportData(cli::array<Point3dWrap^>^ vertices, cli::array<TriangleWrap^>^ faces, int fTarget); 81 int OutputData([Out] cli::array<Point3dWrap^>^% vertices, [Out] cli::array<TriangleWrap^>^% faces); 82 83 int TestParam1(cli::array<Point3dWrap^>^ datas); 84 bool Uninitialize(); 85 86 87 private: 88 Mesh *mesh; 89 int faceTarget; 90 void InitM0(); 91 void ReplaceM(); 92 int Run(); 93 }; 94 95 QSlimWrap::QSlimWrap() 96 { 97 mesh = new Mesh; 98 } 99 100 QSlimWrap::~QSlimWrap() 101 { 102 Uninitialize(); 103 } 104 105 bool QSlimWrap::Uninitialize() 106 { 107 DisposeQS(); 108 if (mesh) 109 { 110 delete mesh; 111 mesh = NULL; 112 } 113 else 114 return false; 115 return true; 116 } 117 118 int QSlimWrap::TestParam1(cli::array<Point3dWrap^>^ datas) 119 { 120 return 12; 121 } 122 123 int QSlimWrap::ReadFile(char* file) 124 { 125 Mesh m; 126 PlyManager::ReadFile(m, file);//result_decix 127 mesh->Vertices = m.Vertices; 128 mesh->Faces = m.Faces; 129 faceTarget = 2 * m.Faces.size() / 3; 130 Run(); 131 return 1; 132 } 133 134 int QSlimWrap::OutputFile(char* newFile) 135 { 136 Mesh m; 137 m.Vertices = mesh->Vertices; 138 m.Faces = mesh->Faces; 139 PlyManager::Output(m, newFile); 140 cerr << "Output File:" << newFile << endl; 141 return 0; 142 } 143 144 void QSlimWrap::InitM0() 145 { 146 for (size_t i = 0;i < mesh->Vertices.size();i++) 147 { 148 Point3d p = mesh->Vertices[i]; 149 Vec3 v(p.X, p.Y, p.Z); 150 //M0.in_Vertex(v); 151 M0.in_VertexEx(v, p.R, p.G, p.B); 152 } 153 for (size_t i = 0;i < mesh->Faces.size();i++) 154 { 155 Triangle t = mesh->Faces[i]; 156 //M0.in_Face(t.P0Index,t.P1Index,t.P2Index); 157 M0.in_FaceEx(t.P0Index, t.P1Index, t.P2Index, t.R, t.G, t.B); 158 } 159 } 160 161 void QSlimWrap::ReplaceM() 162 { 163 mesh->Vertices.swap(std::vector<Point3d>()); 164 mesh->Faces.swap(std::vector<Triangle>()); 165 mesh->Vertices.reserve(M0.vertCount()); 166 mesh->Faces.reserve(M0.faceCount()); 167 int* map = new int[M0.vertCount()]; 168 for (int i = 0;i < M0.vertCount();i++) 169 map[i] = -1; 170 int number = 0, number1 = 0; 171 for (int i = 0;i < M0.vertCount();i++) 172 { 173 if (M0.vertex(i)->isValid()) 174 { 175 real* data = M0.vertex(i)->raw(); 176 //Point3d p((float)data[0], (float)data[1], (float)data[2]); 177 Point3d p((float)data[0], (float)data[1], (float)data[2], M0.vertex(i)->R, M0.vertex(i)->G, M0.vertex(i)->B); 178 map[i] = mesh->AddVertex(p); 179 number++; 180 } 181 else 182 number1++; 183 } 184 cerr << "ReplaceM M0 Vertices valid number: " << number << " not valid number : " << number1 << " total Count:" << M0.vertCount()<< endl; 185 number=0, number1=0; 186 for (int i = 0;i < M0.faceCount();i++) 187 { 188 if (M0.face(i)->isValid()) 189 { 190 Vertex* v0 = M0.face(i)->vertex(0); 191 Vertex* v1 = M0.face(i)->vertex(1); 192 Vertex* v2 = M0.face(i)->vertex(2); 193 //Triangle t(map[v0->uniqID], map[v1->uniqID], map[v2->uniqID]); 194 Triangle t(map[v0->uniqID], map[v1->uniqID], map[v2->uniqID], M0.face(i)->R, M0.face(i)->G, M0.face(i)->B); 195 mesh->AddFace(t); 196 number++; 197 } 198 else 199 number1++; 200 } 201 cerr << "ReplaceM M0 faces valid number: " << number << " not valid number : " << number1 << " total Count:" << M0.faceCount() << endl; 202 delete[] map; 203 } 204 205 int QSlimWrap::Run() 206 { 207 InitM0(); 208 //cerr << "InportData runing fTarget =" << face_target << endl; 209 //qslim_init(); 210 face_target = faceTarget;//2 * m.Faces.size() / 3; 211 error_tolerance = HUGE; 212 will_use_plane_constraint = true; 213 will_use_vertex_constraint = false; 214 will_preserve_boundaries = true; 215 will_preserve_mesh_quality = true; 216 will_constrain_boundaries = true; 217 boundary_constraint_weight = 1.0; 218 will_weight_by_area = false; 219 placement_policy = 1; 220 pair_selection_tolerance = 0.0; 221 qslim_run(); 222 ReplaceM(); 223 return 1; 224 } 225 226 int QSlimWrap::InportData(cli::array<Point3dWrap^>^ vertices, cli::array<TriangleWrap^>^ faces, int fTarget) 227 { 228 int vCount = vertices->LongLength; 229 int fCount = faces->LongLength; 230 faceTarget = fTarget; 231 float v1 = 0, v2 = 0, v3 = 0; 232 int r = 0, g = 0, b = 0; 233 long i1 = 0, i2 = 0, i3 = 0; 234 235 for (long i = 0;i < vCount;i++) 236 { 237 Point3dWrap^ ver = (Point3dWrap^)vertices[i]; 238 Point3d p3d(ver->X, ver->Y, ver->Z, ver->R, ver->G, ver->B); 239 mesh->AddVertex(p3d); 240 } 241 delete[] vertices; 242 243 for (long j = 0;j < fCount;j++) 244 { 245 TriangleWrap^ tg = faces[j]; 246 Triangle t(tg->pIndex0, tg->pIndex1, tg->pIndex2, tg->R, tg->G, tg->B); 247 mesh->AddFace(t); 248 } 249 delete[] faces; 250 cerr << "InportData run before Vertices Count:" << mesh->Vertices.size() << " face_target:" << faceTarget << endl; 251 Run(); 252 cerr << "InportData run completed Vertices Count:" << mesh->Vertices.size() << " faces Count: "<< mesh->Faces.size() <<endl; 253 return 1; 254 } 255 256 257 int QSlimWrap::OutputData([Out] cli::array<Point3dWrap^>^% vertices, [Out] cli::array<TriangleWrap^>^% faces) 258 { 259 int vCount = mesh->Vertices.size(); 260 vertices = gcnew cli::array<Point3dWrap^>(vCount); 261 for (int i = 0;i < vCount;i++) 262 { 263 Point3d v = mesh->Vertices[i]; 264 Point3dWrap^ ver = gcnew Point3dWrap(); 265 ver->X = v.X, ver->Y = v.Y, ver->Z = v.Z, ver->R = v.R, ver->G = v.G, ver->B = v.B; 266 vertices[i] = ver; 267 } 268 mesh->Vertices.clear(); 269 270 int fCount = mesh->Faces.size(); 271 faces = gcnew cli::array<TriangleWrap^>(fCount); 272 for (int i = 0;i < fCount;i++) 273 { 274 Triangle t = mesh->Faces[i]; 275 TriangleWrap^ tw = gcnew TriangleWrap(t.P0Index, t.P1Index, t.P2Index, t.R, t.G, t.B); 276 faces[i] = tw; 277 } 278 279 mesh->Faces.clear(); 280 cerr << "OutputData vertices Count:" << vCount << " faces Count:" << fCount << endl; 281 return 1; 282 } 283 }
三,Wraper验证
新建C# 项目,引用QSlimWraper.dll,验证代码如下:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
1 static void Main(string[] args) 2 { 3 4 QSlimWraper wrap = new QSlimWraper(); 5 unsafe 6 { 7 //Point3d[] test = new Point3d[10]; 8 //for (int i = 0; i < 10; i++) 9 //{ 10 // test[i].X = i + 1; 11 //} 12 13 string str = "E:\\resultXXX2.ply"; 14 IntPtr intPtrStr = (IntPtr)Marshal.StringToHGlobalAnsi(str); 15 sbyte* sbyteStr = (sbyte*)intPtrStr; 16 int res = wrap.ReadFile(sbyteStr); 17 18 str = "E:\\resultXXX2XXX.ply"; 19 intPtrStr = (IntPtr)Marshal.StringToHGlobalAnsi(str); 20 sbyteStr = (sbyte*)intPtrStr; 21 int res1 = wrap.OutputFile(sbyteStr); 22 23 //Point3dWrap[] pts = new Point3dWrap[100]; 24 //for (int i = 0; i < 100; i++) 25 //{ 26 // Point3dWrap aa = new Point3dWrap(); 27 // aa.X = i + 1; 28 // pts[i] = aa; 29 //} 30 //TriangleWrap[] ts = new TriangleWrap[300]; 31 //for (int i = 0; i < 100; i++) 32 //{ 33 // TriangleWrap aa = new TriangleWrap(); 34 // aa.pIndex0 = i; 35 // aa.pIndex1 = i + 100; 36 // aa.pIndex2 = i + 200; 37 // ts[i] = aa; 38 //} 39 ////int iii = wrap.TestParam1(test); 40 //int face_target = 2 * ts.Length / 3; 41 //wrap.InportData(pts, ts, face_target); 42 //Point3dWrap[] point3Ds; 43 //TriangleWrap[] triangles; 44 //wrap.OutputData(out point3Ds, out triangles); 45 wrap.Dispose(); 46 } 47 }
四,示例效果,19800 surfaces to 1000 surfaces
如需要原码可联系