Submission from Perry Miller for support of OpenFlight15.7's local vertex pool

and mesh primitives.  Converted Perry's code to work with the osg::Geometry
instead of osg::GeoSet.

src/osgPlugins/flt/MeshPrimitiveRecord.cpp

@@ -0,0 +1,145 @@
+// MeshPrimitiveRecords.cpp
+
+#ifdef _WIN32
+#pragma warning(disable:4786) // Truncated debug names.
+#endif
+
+#include "MeshPrimitiveRecord.h"
+#include "Registry.h"
+#include <assert.h>
+
+using namespace flt;
+
+
+////////////////////////////////////////////////////////////////////
+//
+//                       MeshPrimitiveRecord
+//
+////////////////////////////////////////////////////////////////////
+
+RegisterRecordProxy<MeshPrimitiveRecord> g_MeshPrimitiveProxy;
+
+MeshPrimitiveRecord::MeshPrimitiveRecord() : PrimNodeRecord()
+{
+}
+
+
+// virtual
+MeshPrimitiveRecord::~MeshPrimitiveRecord()
+{
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+//
+//  Return the address of the beginning of the vertex indices.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+char *MeshPrimitiveRecord::_getStartOfVertexIndices() const
+{
+  SMeshPrimitive *mesh = this->getData();
+  char *index = (char *) (&(mesh[1]));
+  return index;
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+//
+//  Get the index into the local vertex pool for the given i'th vertex of 
+//  this mesh primitive.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+bool MeshPrimitiveRecord::getVertexIndex ( const uint32 &whichVertex, uint32 &index ) const
+{
+  assert ( whichVertex < this->getNumVertices() );
+
+  // Get pointer to start of vertex indices.
+  char *start = (char *) this->_getStartOfVertexIndices();
+
+  // Need a pointer to the mesh structure.
+  SMeshPrimitive *mesh = this->getData();
+
+  // Move the pointer to the beginning of the requested vertex index. We are 
+  // treating the array of indices as an array of chars (8 bits) so we have to
+  // multiply times the correct elements size (mesh->indexSize) to get the 
+  // correct index.
+  uint32 adjust = whichVertex * ((uint32) mesh->indexSize);
+  start = &start[adjust];
+
+  // The index "adjust" that we just calculated should not walk off the end.
+  assert ( adjust <= mesh->indexSize * mesh->numVerts );
+
+  // Interpret the address "start" correctly...
+  switch ( mesh->indexSize )
+  {
+  case sizeof ( uint32 ): index =           *((uint32 *) start);  break; // No cast required.
+  case sizeof ( uint16 ): index = (uint32) (*((uint16 *) start)); break;
+  case sizeof ( uint8  ): index = (uint32) (*((uint8 *)  start)); break;
+  default:
+
+    assert ( 0 ); // Invalid index size (according to 15.7.0 specs).
+    return false;
+  }
+
+  // It worked.
+  return true;
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+//
+//  Convert the data from big-endian to little-endian.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+void MeshPrimitiveRecord::endian()
+{
+  // Should only be in here for little-endian machines.
+  assert ( flt::isLittleEndianMachine() );
+
+  SMeshPrimitive *mesh = this->getData();
+  ENDIAN ( mesh->primitiveType );
+  ENDIAN ( mesh->indexSize );
+  ENDIAN ( mesh->numVerts );
+
+  // Get pointer to start of vertex indices.
+  char *index = this->_getStartOfVertexIndices();
+
+  // Determine the size of the elements in the array of vertex indices.
+  switch ( mesh->indexSize )
+  {
+  case sizeof ( uint32 ): // 32 bits.
+
+    // Perform byte-swap on all the elements in the array.
+    flt::swapBytesArray ( sizeof ( uint32 ), mesh->numVerts, (uint32 *) index );
+    break;
+
+  case sizeof ( uint16 ): // 16 bits.
+
+    // Perform byte-swap on all the elements in the array.
+    flt::swapBytesArray ( sizeof ( uint16 ), mesh->numVerts, (uint16 *) index );
+    break;
+
+  case sizeof ( uint8 ): // 8 bits.
+
+    // We don't have to swap bytes because there is only one byte.
+    break;
+
+  default:
+
+    assert ( 0 ); // Invalid index size (according to 15.7.0 specs).
+  }
+
+#ifdef _DEBUG
+  // Sanity check. The address immediately following the last element, 
+  // minus the start of this record, should be the size of this record.
+  char *offEndC = &(index[mesh->numVerts * mesh->indexSize]);
+  uint32 offEndI = (uint32) offEndC;
+  uint32 indexI = (uint32) mesh;
+  uint32 diff32 = ( offEndI ) - ( indexI );
+  uint16 diff16 = (uint16) ( diff32 );
+  assert ( mesh->RecHeader._wLength == diff16 );
+#endif
+}