Implementing CAD viewing and Conversion tool for LVO-VROM

The Business Challenge

LVO-VROM, Netherlands deals primarily with
Spatial Planning and Development, Urban Development and Environment Management for the Dutch populace and consequently monitors and manipulates host of CAD design documents related to various projects. These documents need to be uploaded to a repository, viewed during decision-making procedures, printed for official purposes and converted to viewable formats and stored in the repository. Consequently, their  core requirement was that of a CAD viewer that would ideally be able to  view and annotate CAD and other file formats including AutoCAD, MicroStation, DWF, DXF etc and a converter that would convert specified source file types to viewable formats PNG, TIFF, PDF , SVG etc. Moreover, being a government agency with different hierarchies of users, the solution needed to comply with stringent role-based user access rights and privileges.

Web4 helped VROM meet and surpass this requirement of a CAD viewing and conversion tool with its combined solution of eReview-Rendition server. eReview supports a host of file formats  (over 200), including Microsoft Office documents, printer outputs, CAD drawings (such as AutoCAD DWG, DXF, DWF, MicroStation DGN), Portable Document Formats (PDF), Scanned and other Raster Images (such as TIFF, PNG, GIF, and JPEG) and many more. Rendition Server augments eReview to support file conversion. It is  Web Application, leveraging the SOAP mechanism and enabling remote execution of the conversion processes. Being an intelligent viewer, Review allows users to view AutoCad and other design documents in their native format in a web-based environment. Retaining the original elements of the files (such as layers, blocks, xrefs in AutoCAD, brightness, and contrast etc. in scanned images), eReview allows teams to view and annotate the native documents without the help of any originating application. Role-based user- profiling helped in configuring and customizing the product interface according to user roles and hierarchies


The Solution


Web4’ combined solution of eReview-Rendition Server contains two components, viz eReview and Rendition server. eReview contains all the components required for the CADViewer deployment and Rendition Server contains the document upload and conversion tools.

  • eReview’s Multiple Document interface allows a multitude of files in a host of varying formats to be viewed and annotated in a single instance of the viewer
  • On the other hand, the Rendition Server allows conversion of source files to target files. Components called “Convertlets” help process the source files and convert them to target files. This conversion is based on the parameters provided in the SOAP method request. Based on this information the appropriate convertlet gets executed based on the configuration information. Rendition Server uses EVEF, which is the same viewing engine, used in eReview. Hence Rendition Server supports the same native formats as ereview The solutions may be used as an interactive web service to convert files one at a time, or alternatively as a batch process to convert any number of files offline
  • The upload utility is provided with the front-end to upload document using both multipart form upload and java applet based upload utility. There is an Upload Servlet configured to save the metadata information in the database and queue the new document being uploaded for the batch conversion process. The server is configured to trigger the batch conversion process in a specified time. After completion of the conversion process the converted document information is posted back into the database. After each completion or failure of a batch process an e-mail notification is sent to the system administrator
  • Role-based user access mechanism is defined clearly for the solution and eleven specific user profiles have been created based on the requirements of the organization
  • Some specific parameters are introduced to control the display name, user’s role, organization name, user name, markup flag and case id nad are passed through the URL. eReview markups are extremely secure, with author name, date and timestamp being maintained for each markup file. Moreover, the concept of presentation layer and user’s role specific layers was defined specifically for VROM. The presentation layer contains the markup objects which are visible to each user role. The content of this layer can only be compiled by a super user who is called the coordinator. By default, this layer is visible while opening a document. It is possible to overwrite this setting with a parameter in the eReview calling sequence. The user-role specific layers are automatically generated for each user role with “Markup Edit” permission. These user roles can add markup objects to their specific layers. When viewing a file the user roles will only see the presentation layer as well as their own layer, but not the layers of other user roles. The storing of markup files happens automatically by eReview and the markup files are stored alongside the files converted by the rendition server along with the markup version in a predefined directory

Bottomline ROI:

  • eReview, a truly Web-based MDI viewer, in conjunction with the Rendition server converter eliminates the cost involved for installing and maintaining multiple software for native CAD viewing, annotation, file upload, conversion and batch printing. A zero-client administration solution, updates at the server get automatically propagated to the client
  • A well-defined role-based user access mechaniam is mandatory VROM and eReview, with its easily configurable XML driven user-profiling mechanism, fits the bill perfectly. Profiling helps scale the product interface according to the user roles and assignments, ranging from simple tools for novice users to highly developed tools and menus for advanced users
  • Unique markup handling methodology introduced specifically for VROM complements the security and access control requirements of a Government agency by insuring complete markup sanctity

Company Profile

The Dutch Ministry of Housing (LVO VROM) plays a key role in optimizing services in the field of housing, space and environment for the people of Netherlands.
Company Website

Industry: Government

Primary Business Requirement:
Native viewer and document upload & conversion tool to handle in-process CAD files

Web4’s Solution: eReview/Rendition Server