Uniform laplacian smoothing and tangential version

xionluhnis · Aug 19, 2014 · 29f218d · 29f218d
1 parent 5a73575
commit 29f218d
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Showing 2 changed files with 59 additions and 1 deletion.
diff --git a/example-visualize/src/ofApp.cpp b/example-visualize/src/ofApp.cpp
@@ -59,12 +59,16 @@ void ofApp::update(){
     Surface_mesh::Face_property<float> fdata;
     switch(prop){
       case OGP_UNIFORM_MEAN_CURVATURE:
+        ofxOpenGP::voronoi_area(mesh);
         vdata = ofxOpenGP::uniform_mean_curvature(mesh);
         break;
       case OGP_MEAN_CURVATURE:
+        ofxOpenGP::voronoi_area(mesh);
+        ofxOpenGP::cot_pair(mesh);
         vdata = ofxOpenGP::mean_curvature(mesh);
         break;
       case OGP_GAUSS_CURVATURE:
+        ofxOpenGP::voronoi_area(mesh);
         vdata = ofxOpenGP::gauss_curvature(mesh);
         break;
       case OGP_VORONOI_AREA:
@@ -172,13 +176,25 @@ void ofApp::keyPressed(int key){
         }
       }
       break;
+    case 's':
+      std::cout << "Smoothing of mesh.\n";
+      ofxOpenGP::laplace_uniform_smooth(mesh);
+      mesh.update_vertex_normals();
+      propChanged = true;
+      break;
+    case 't':
+      std::cout << "Tangential smoothing of mesh.\n";
+      ofxOpenGP::laplace_uniform_smooth(mesh, true);
+      mesh.update_vertex_normals();
+      propChanged = true;
+      break;
     case 'h':
       help = !help;
       break;
     case ' ':
       {
         ofFile file(ofToDataPath(path));
-        ofFileDialogResult res = ofSystemLoadDialog("Chose mesh file (.obj, .off, .ply)", false, file.getEnclosingDirectory());
+        ofFileDialogResult res = ofSystemLoadDialog("Choose mesh file (.obj, .off, .ply)", false, file.getEnclosingDirectory());
         if(!res.bSuccess) return;
         if(!ofFile(res.getPath()).canRead()) return;
         path = res.getPath();

diff --git a/src/ofxOpenGP.h b/src/ofxOpenGP.h
@@ -583,4 +583,46 @@ class ofxOpenGP {
       return col;
     }
 
+    ///////////////////////////////////////////////////////////////////////////
+    ///// Mesh operations /////////////////////////////////////////////////////
+    ///////////////////////////////////////////////////////////////////////////
+    static void laplace_uniform_smooth(Surface_mesh &mesh, bool tangential = false, unsigned int rounds = 5, float eta = 0.5){
+      Surface_mesh::Vertex_property<Vec3> laplace = mesh.vertex_property<Vec3>("v:tmp:vec3f");
+      Surface_mesh::Vertex_property<Normal> normals = mesh.vertex_property<Normal>("v:normal");
+      if(tangential){
+        mesh.update_vertex_normals();
+      }
+      for(unsigned int r = 0; r < rounds; ++r){
+        Surface_mesh::Vertex_iterator v_it, v_end = mesh.vertices_end();
+        for(v_it = mesh.vertices_begin(); v_it != v_end; ++v_it){
+          Vec3 barycenter(0, 0, 0);
+          int val = 0;
+          Surface_mesh::Vertex_around_vertex_circulator vv_it, vv_end;
+          vv_it = vv_end = mesh.vertices(*v_it);
+          do {
+            barycenter += mesh.position(*vv_it);
+            ++val;
+          } while (++vv_it != vv_end);
+          barycenter *= 1.0f / val;
+          Vec3 u = barycenter - mesh.position(*v_it);
+          if(tangential){
+            Normal n = normals[*v_it];
+            float n_norm = n.norm();
+            if(n_norm == 0 || n_norm != n_norm){
+              u = Normal(0, 0, 0);
+            } else {
+              // tangential component of u
+              u = u - n * u.dot(n) / n_norm;
+            }
+          }
+          laplace[*v_it] = u;
+        }
+        // apply shift
+        for(v_it = mesh.vertices_begin(); v_it != v_end; ++v_it){
+          if(mesh.is_boundary(*v_it)) continue;
+          mesh.position(*v_it) += laplace[*v_it] * eta;
+        }
+      }
+    }
+
 };