js for dwg viewer in B/S

https://github.com/autodesk-forge/

https://sharecad.org/zh/DWGOnlinePlugin

http://3d-viewers.com/license.html

https://sourceforge.net/projects/js-cad/files/?source=navbar

https://github.com/mmik005/js-cad

https://github.com/qcad/qcad

http://duchangyu.github.io/51CTO/#/25

https://github.com/LibreCAD/LibreCAD

http://www.qcad.org/en/component/content/article/78-qcad/111-qcad-compilation-from-sources

https://github.com/Autodesk-Forge/design.automation-custom-data-viewer

DWG to PNG:

https://github.com/loftuxab/alfresco-vector-transformations-module