V. CONCLUSION
As the basis of 3D geographic language, 3D symbolic
model has broken through the abstract representation of the
traditional 1D literal expression and 2D graphical
symbolization. It promotes the emergence of 3D and multi-
dimensional language. It enables the traditional expression of
2D and static geographical language to develop into 3D and
dynamic scenes. The research on 3D symbolic model has a
very important significance for further understanding the
essence of 3D GIS and promoting 3D model standardization
and expanding the application of 3D GIS and so on