From Santosh Gaikwad, ply plugin, based on Equalizer and other LGPL compatible sources.

"Attached is the osg-plugin for reading ply ( Stanford Triangle Format )  file. I have written  the plugin according to OSG standard and  have also added cmake build system. The plugin is working fine on both Linux and Windows and should behave similarly on other OS as well."

"I developed this plugin while working on a project based on Equalizer. So VertexData which I am using is taken from equalizer and modified to make them work as separate OSG plugin.
Before contributing this plugin to OSG community, I asked project manager of Equalizer project Stefen regarding potential licensing issues and this is what he has said

"The kd-Tree (VertexBuffer*) is LGPL-licensed, and the base ply loader (ply*) is BSD. As long as you leave the copyright notices intact, there is no issue."

so I think using these files in OSG should not be a problem.

As far as author of ReaderWriterPLY.cpp  is concerned I am the author. I am working for Darshan3d which is a subsidiary of VizExperts thats why I have put VizExperts copyright."

src/osgPlugins/ply/ReaderWriterPLY.cpp

@@ -0,0 +1,81 @@
+/*
+ * PLY  ( Stanford Triangle Format )  File Loader for OSG
+ * Copyright (C) 2009 by VizExperts Limited
+ * All rights reserved.
+ *
+ * This program is  free  software;  you can redistribute it and/or modify it
+ * under the terms of the  GNU Lesser General Public License  as published by 
+ * the  Free Software Foundation;  either version 2.1 of the License,  or (at 
+ * your option) any later version.
+ *
+ * This  program  is  distributed in  the  hope that it will  be useful,  but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or  FITNESS FOR A  PARTICULAR PURPOSE.  See the  GNU Lesser General Public  
+ * License for more details.
+ *
+ * You should  have received  a copy of the GNU Lesser General Public License
+ * along with  this program;  if not, write to the  Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <osgDB/Registry>
+#include <osgDB/ReadFile>
+#include <osgDB/FileUtils>
+#include <osgDB/FileNameUtils>
+
+
+#include "vertexData.h"
+
+using namespace osg;
+using namespace osgDB;
+using namespace std;
+
+///////////////////////////////////////////////////////////////////////////////
+//!
+//! \class ReaderWriterPLY
+//! \brief This is the Reader for the ply file format
+//!
+//////////////////////////////////////////////////////////////////////////////
+class ReaderWriterPLY : public osgDB::ReaderWriter
+{
+public:
+    ReaderWriterPLY()
+    {
+        supportsExtension("ply","Stanford Triangle Format");
+    }
+
+    virtual const char* className() { return "ReaderWriterPLY"; }
+    virtual ReadResult readNode(const std::string& fileName, const osgDB::ReaderWriter::Options*) const;
+protected:
+};
+
+// register with Registry to instantiate the above reader/writer.
+REGISTER_OSGPLUGIN(ply, ReaderWriterPLY)
+
+///////////////////////////////////////////////////////////////////////////////
+//!
+//! \brief Function which is called when any ply file is requested to load in
+//! \osgDB. Load read ply file and if it successes return the osg::Node
+//! 
+///////////////////////////////////////////////////////////////////////////////
+osgDB::ReaderWriter::ReadResult ReaderWriterPLY::readNode(const std::string& filename, const osgDB::ReaderWriter::Options* options) const
+{
+    // Get the file extension
+    std::string ext = osgDB::getFileExtension(filename);
+    
+    // If the file extension does not support then return that file is not handled
+    if (!acceptsExtension(ext)) return ReadResult::FILE_NOT_HANDLED;
+
+    // Check whether or not file exist or not  
+    std::string fileName = osgDB::findDataFile(filename, options);
+    if (fileName.empty()) return ReadResult::FILE_NOT_FOUND;
+
+    //Instance of vertex data which will read the ply file and convert in to osg::Node
+    ply::VertexData vertexData;
+    osg::Node* node = vertexData.readPlyFile(filename.c_str());
+
+    if (node) 
+        return node;
+
+    return ReadResult::FILE_NOT_HANDLED;
+}