Add simple example that compute Shape Diameter Function using ray tracing and exploiting VCG library indexing structure

apps/sample/trimesh_ray/trimesh_ray.cpp

@@ -0,0 +1,146 @@
+#include <vector>
+
+using namespace std;
+
+// VCG headers for triangular mesh processing
+#include<vcg/simplex/edge/base.h>
+#include<vcg/simplex/vertex/base.h>
+#include<vcg/simplex/face/base.h>
+#include <vcg/complex/trimesh/base.h>
+#include <vcg/complex/trimesh/update/topology.h>
+#include <vcg/complex/trimesh/update/edges.h>
+#include <vcg/complex/trimesh/update/bounding.h>
+#include <vcg/complex/trimesh/update/quality.h>
+#include <vcg/complex/trimesh/update/color.h>
+#include <vcg/complex/trimesh/update/flag.h>
+#include <vcg/complex/trimesh/clean.h>
+#include <vcg/complex/intersection.h>
+#include <vcg/space/index/grid_static_ptr.h>
+#include <vcg/space/index/spatial_hashing.h>
+#include <vcg/complex/trimesh/closest.h>
+
+// VCG File Format Importer/Exporter
+#include <wrap/io_trimesh/import.h>
+#include <wrap/io_trimesh/export_ply.h>
+
+using namespace vcg;
+
+class MyFace;
+class MyEdge;
+class MyVertex;
+
+struct MyUsedTypes : public UsedTypes<	Use<MyVertex>		::AsVertexType,
+                                        Use<MyEdge>			::AsEdgeType,
+																				Use<MyFace>			::AsFaceType>{};
+
+
+class MyVertex  : public Vertex< MyUsedTypes, vertex::Coord3f, vertex::BitFlags, vertex::Normal3f, vertex::Mark,vertex::Color4b, vertex::Qualityf>{};
+class MyFace    : public Face  <MyUsedTypes, face::VertexRef,face::BitFlags,face::Mark, face::Normal3f> {};
+
+class MyMesh : public tri::TriMesh< vector<MyVertex>, vector<MyFace > >{};
+
+typedef vcg::GridStaticPtr<MyMesh::FaceType, MyMesh::ScalarType> TriMeshGrid;
+
+int main(int argc,char ** argv)
+{
+  if (argc<2)
+	{
+		printf("\n");
+    printf("    Compute an approximation of the shape diameter function\n");
+    printf("    Usage: trimesh_intersection <filename> [angle samplenum]\n\n");
+    printf("       <filename>        Mesh model for which to compute the sdf (PLY format).\n");
+    printf("       angle             the wideness (degree) of the cone of ray that must be shot from each vertex (default 45)\n");
+    printf("       samplenum         the oversampling factor (0 -> one ray, 1, 9 ray, 2-> 25 rays (default 2)\n");
+
+		return 0;
+	}
+
+	MyMesh m;
+
+	// open a mesh
+	int err = tri::io::Importer<MyMesh>::Open(m,argv[1]);
+	if(err) 
+	{
+		printf("Error in reading %s: '%s'\n",argv[1],tri::io::Importer<MyMesh>::ErrorMsg(err));
+		exit(-1);  
+	}
+// the other parameters
+  float widenessRad = math::ToRad(20.0);
+
+  if(argc>2) {
+    widenessRad = math::ToRad(atof(argv[2]));
+    printf("Setting wideness to %f degree\n",atof(argv[2]));
+  }
+
+  int n_samples=2;
+  if(argc>3) {
+    n_samples = atoi(argv[3]);
+    printf("Setting oversampling to %i \n",n_samples);
+  }
+
+	// some cleaning to get rid of bad file formats like stl that duplicate vertexes..
+	int dup = tri::Clean<MyMesh>::RemoveDuplicateVertex(m);
+	int unref =  tri::Clean<MyMesh>::RemoveUnreferencedVertex(m);
+
+	if (dup > 0 || unref > 0)
+		printf("Removed %i duplicate and %i unreferenced vertices from mesh %s\n",dup,unref,argv[1]);
+
+  // updating
+  tri::UpdateBounding<MyMesh>::Box(m);
+  tri::UpdateNormals<MyMesh>::PerFaceNormalized(m);
+  tri::UpdateNormals<MyMesh>::PerVertexAngleWeighted(m);
+  tri::UpdateNormals<MyMesh>::NormalizeVertex(m);
+  tri::UpdateFlags<MyMesh>::FaceProjection(m);
+	// Create a static grid (for fast indexing) and fill it
+	TriMeshGrid static_grid;
+	static_grid.Set(m.face.begin(), m.face.end());
+	std::vector<TriMeshGrid::Cell *> intersected_cells;
+  typedef MyMesh::ScalarType ScalarType;
+
+  float t;
+  MyMesh::FaceType *rf;
+  MyMesh::VertexIterator vi;
+  float maxDist=m.bbox.Diag();
+  float offset= maxDist / 10000.0;
+
+
+  ScalarType deltaRad=widenessRad/(ScalarType)(n_samples*2);
+
+  tri::UpdateQuality<MyMesh>::VertexConstant(m,0);
+  for(vi=m.vert.begin();vi!=m.vert.end();++vi)
+  {
+    vcg::Ray3f ray;
+    ray.SetOrigin((*vi).cP()-((*vi).cN()*offset));
+    Point3f dir0 = -(*vi).cN();
+    int cnt=0;
+    ScalarType theta_init,phi_init,ro;
+    dir0.ToPolarRad(ro,theta_init,phi_init);
+    for (int x=-n_samples;x<=n_samples;x++)
+      for (int y=-n_samples;y<=n_samples;y++)
+      {
+        ScalarType theta=theta_init+x*deltaRad;
+        ScalarType phi=phi_init+y*deltaRad;
+
+        if (theta<0) theta=2.0*M_PI+theta;
+
+        Point3f dir;
+        dir.FromPolarRad(ro,theta,phi);
+        dir.Normalize();
+        ray.SetDirection(dir);
+
+        rf = tri::DoRay<MyMesh,TriMeshGrid>(m,static_grid,ray,maxDist,t);
+        if(rf)
+        {
+          (*vi).Q()+=t;
+          cnt++;
+        }
+      }
+    if(cnt>0)
+      (*vi).Q()/=cnt;
+  }
+  tri::UpdateColor<MyMesh>::VertexQualityRamp(m);
+  tri::io::ExporterPLY<MyMesh>::Save(m,"Pippo.ply",tri::io::Mask::IOM_VERTCOLOR+tri::io::Mask::IOM_VERTQUALITY);
+
+	return 0;
+}
+

apps/sample/trimesh_ray/trimesh_ray.pro

@@ -0,0 +1,10 @@
+TARGET = trimesh_ray
+LIBPATH += 
+DEPENDPATH += . 
+INCLUDEPATH += . ../../..
+CONFIG += console stl 
+TEMPLATE = app
+SOURCES += trimesh_ray.cpp ../../../wrap/ply/plylib.cpp
+
+# Mac specific Config required to avoid to make application bundles
+CONFIG -= app_bundle