loadPLYSimple basic automatic detection of normals, color, and alpha properties

modules/surface_matching/include/opencv2/surface_matching/ppf_helpers.hpp

@@ -61,7 +61,7 @@ namespace ppf_match_3d
  *  and whether it should be loaded or not
  *  @return Returns the matrix on successfull load
  */
-CV_EXPORTS Mat loadPLYSimple(const char* fileName, int withNormals);
+CV_EXPORTS Mat loadPLYSimple(const char* fileName, int withNormals = 0);
 
 /**
  *  @brief Write a point cloud to PLY file

modules/surface_matching/src/ppf_helpers.cpp

@@ -69,10 +69,13 @@ std::vector<std::string> split(const std::string &text, char sep) {
 
 
 
-Mat loadPLYSimple(const char* fileName, int withNormals)
+Mat loadPLYSimple(const char* fileName, int withNormals /* = 0 */)
 {
   Mat cloud;
   int numVertices=0;
+  int numCols=3;
+  bool with_color = false;
+  bool with_alpha = false; // alpha transparency
 
   std::ifstream ifs(fileName);
 
@@ -90,41 +93,57 @@ Mat loadPLYSimple(const char* fileName, int withNormals)
     {
       numVertices = atoi(tokens[2].c_str());
     }
+    if (tokens.size() ==3 && tokens[0] == "property")
+    {
+      if(tokens[3]=="nx" || tokens[3]=="normal_x" )
+      {
+        withNormals = true;
+        numCols+=3;
+      }
+      else if(tokens[3]=="r" || tokens[3]=="red" )
+      {
+        with_color = true;
+        numCols+=3;
+      }
+      else if(tokens[3]=="a" || tokens[3]=="alpha" )
+      {
+        with_alpha = true;
+        numCols+=1;
+      }
+    }
     else if (tokens.size() > 1 && tokens[0] == "format")
     {
       if (tokens[1]!="ascii"){
         printf("Cannot read file, only ascii ply format is currently supported...\n");
+        // uncomment below when CV_StsBadArg can be located
+        //OPENCV_ERROR (CV_StsBadArg, "loadPLYSimple", "Cannot read file, only ascii ply format is currently supported...");
         return Mat();
       }
     }
     std::getline(ifs, str);
   }
 
-  if (withNormals)
-    cloud=Mat(numVertices, 6, CV_32FC1);
-  else
-    cloud=Mat(numVertices, 3, CV_32FC1);
+  cloud=Mat(numVertices, numCols, CV_32FC1);
 
   for (int i = 0; i < numVertices; i++)
   {
     float* data = cloud.ptr<float>(i);
+    for (int col = 0; col < numCols; ++col)
+    {
+      ifs >> data[col];
+    }
     if (withNormals)
     {
-      ifs >> data[0] >> data[1] >> data[2] >> data[3] >> data[4] >> data[5];
 
       // normalize to unit norm
       double norm = sqrt(data[3]*data[3] + data[4]*data[4] + data[5]*data[5]);
       if (norm>0.00001)
       {
-        data[3]/=(float)norm;
-        data[4]/=(float)norm;
-        data[5]/=(float)norm;
+        data[3]/=static_cast<float>(norm);
+        data[4]/=static_cast<float>(norm);
+        data[5]/=static_cast<float>(norm);
       }
     }
-    else
-    {
-      ifs >> data[0] >> data[1] >> data[2];
-    }
   }
 
   //cloud *= 5.0f;