From 84d8eeb7cb686acec741750c96f34df8b46b272b Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Tue, 11 Dec 2012 09:55:48 +0000
Subject: [PATCH] First cut of generating lines from .trk data

---
 src/osgPlugins/trk/ReaderWriterTRK.cpp | 109 +++++++++++++++++++++++--
 1 file changed, 101 insertions(+), 8 deletions(-)

diff --git a/src/osgPlugins/trk/ReaderWriterTRK.cpp b/src/osgPlugins/trk/ReaderWriterTRK.cpp
index ae034f13f..dad4a58e5 100644
--- a/src/osgPlugins/trk/ReaderWriterTRK.cpp
+++ b/src/osgPlugins/trk/ReaderWriterTRK.cpp
@@ -1,9 +1,9 @@
 // Released under the OSGPL license, as part of the OpenSceneGraph distribution.
 //
 // specification : http://www.trackvis.org/docs/?subsect=fileformat
+//
 #include <osg/Geode>
-
-#include <osg/GL>
+#include <osg/io_utils>
 
 #include <osgDB/FileNameUtils>
 #include <osgDB/FileUtils>
@@ -69,20 +69,113 @@ class ReaderWriterTRK : public osgDB::ReaderWriter
             if (fin.fail()) return ReadResult::ERROR_IN_READING_FILE; 
 
             OSG_NOTICE<<"Read header successfuly ["<<header.id_string<<"]"<<std::endl;
-            OSG_NOTICE<<"version = "<<header.version<<std::endl;
-            int swaped_version = header.version;
-            osg::swapBytes(swaped_version);
-            if (header.version>swaped_version)
+            bool requiresByteSwap = header.hdr_size!=1000;
+            if (requiresByteSwap)
             {
-                OSG_NOTICE<<"Requires byteswap"<<std::endl;
+                OSG_NOTICE<<"Requires byteswap, but not implemented yet."<<std::endl;
+                return ReadResult::FILE_NOT_HANDLED;
             }
             else
             {
                 OSG_NOTICE<<"No byteswap required"<<std::endl;
             }
+
+            OSG_NOTICE<<"version = "<<header.version<<std::endl;
+            OSG_NOTICE<<"dim = "<<header.dim[0]<<", "<<header.dim[1]<<", "<<header.dim[2]<<std::endl;
+            OSG_NOTICE<<"voxel_size = "<<header.voxel_size[0]<<", "<<header.voxel_size[1]<<", "<<header.voxel_size[2]<<std::endl;
+            OSG_NOTICE<<"origin = "<<header.origin[0]<<", "<<header.origin[1]<<", "<<header.origin[2]<<std::endl;
+            OSG_NOTICE<<"n_scalars = "<<header.n_scalars<<std::endl;
+            OSG_NOTICE<<"n_properties = "<<header.n_properties<<std::endl;
+
+            osg::Matrixf matrix(reinterpret_cast<const float*>(header.vox_to_ras));
+            OSG_NOTICE<<"vox_to_ras="<<matrix<<std::endl;
             
+            OSG_NOTICE<<"invert_x="<<static_cast<int>(header.invert_x)<<std::endl;
+            OSG_NOTICE<<"invert_y="<<static_cast<int>(header.invert_y)<<std::endl;
+            OSG_NOTICE<<"invert_z="<<static_cast<int>(header.invert_z)<<std::endl;
+            OSG_NOTICE<<"swap_xy="<<static_cast<int>(header.swap_xy)<<std::endl;
+            OSG_NOTICE<<"swap_yz="<<static_cast<int>(header.swap_yz)<<std::endl;
+            OSG_NOTICE<<"swap_zx="<<static_cast<int>(header.swap_zx)<<std::endl;
+            OSG_NOTICE<<"n_count="<<header.n_count<<std::endl;
+            OSG_NOTICE<<"hdr_size="<<header.hdr_size<<std::endl;
+
+            if (header.n_count==0)
+            {
+                OSG_NOTICE<<"No tracks stored."<<std::endl;
+                return ReadResult::FILE_NOT_HANDLED;
+            }
+
+            int n_s = header.n_scalars;
+            int n_p = header.n_properties;
+
+            osg::ref_ptr<osg::Geode> geode = new osg::Geode;
+
+            osg::ref_ptr<osg::Geometry> geometry = new osg::Geometry;
+            geode->addDrawable(geometry.get());
             
-            return ReadResult::FILE_NOT_HANDLED;
+            osg::ref_ptr<osg::Vec3Array> vertices = new osg::Vec3Array;
+            geometry->setVertexArray(vertices.get());
+
+            osg::ref_ptr<osg::DrawElementsUInt> lines = new osg::DrawElementsUInt(GL_LINES);
+            geometry->addPrimitiveSet(lines.get());
+
+            for(int i=0; i<header.n_count; ++i)
+            {
+                // read track
+                // OSG_NOTICE<<"reading track #"<<i<<std::endl;
+
+                int n_points=0;
+                fin.read(reinterpret_cast<char*>(&n_points),4);
+                if (fin.fail()) break;
+
+                // OSG_NOTICE<<"  n_points="<<n_points<<std::endl;
+
+                int n_floats_per_vertex = (3+n_s);
+                int n_point_floats = n_floats_per_vertex*n_points;
+                float* point_data = new float[n_point_floats];
+                fin.read(reinterpret_cast<char*>(point_data), n_point_floats*4);
+                if (fin.fail()) break;
+                
+                if (n_p!=0)
+                {
+                    float* property_data = new float[n_p];
+                    fin.read(reinterpret_cast<char*>(&property_data), n_p*4);
+                    if (fin.fail()) break;
+
+                    delete [] property_data;
+
+                }
+
+                if (n_points>0)
+                {
+                    // record the index of the first vertex of the new track
+                    int vi = vertices->size();
+
+                    // add the vertices of the track
+                    for(int pi=0; pi<n_points; ++pi)
+                    {
+                        float* vptr = &point_data[pi*n_floats_per_vertex];
+                        vertices->push_back(osg::Vec3(vptr[0],vptr[1],vptr[2]));
+                    }
+
+                    // add the line segmenets for track
+                    for(int pi=0; pi<n_points-1; ++pi, ++vi)
+                    {
+                        lines->push_back(vi);
+                        lines->push_back(vi+1);
+                    }
+                }
+
+                delete [] point_data;
+            }
+            
+            if (fin.fail())
+            {
+                OSG_NOTICE<<"Error on reading track file."<<std::endl;
+                return ReadResult::ERROR_IN_READING_FILE;
+            }
+
+            return geode.release();
         }
 
         virtual ReadResult readNode(const std::string& file, const osgDB::ReaderWriter::Options* options) const