Chroma COLLADA

Current G4DAE material handling are just names, need:

1. implement the GDML G4 material (and surface) wavelength array properties into COLLADA extra tags
2. hmm maybe GDML does not cover wavelength dependant props, will need to devise xml format and handling for that

GDML wavelength dependant properties

• http://lcgapp.cern.ch/project/simu/framework/GDML/doc/GDMLmanual.pdf
• google:optical surfaces gdml
• google:gdml wavelength dependant properties
• http://microboone-docdb.fnal.gov/cgi-bin/RetrieveFile?docid=1000;filename%3DTDRFinal.pdf;version%3D1
• http://geant4.cern.ch/support/ReleaseNotes4.9.3.html

GDML: it is now possible to customise the reader as well as the writer to treat ad-hoc user extensions to the GDML schema. The GDML writer now also supports dumping of optical surface properties associated with surfaces and materials.

• http://www-geant4.kek.jp/lxr/source/persistency/gdml/schema/
• http://www-geant4.kek.jp/lxr/source/persistency/gdml/schema/gdml.xsd