Autodesk: keeping it Real

1102 0

Autodesk recently made its DWG libraries available in a new format for developers and customers, allowing the opening and saving of AutoCAD drawings without the presence of AutoCAD.

Question: When is a DWG file not a DWG file?

ANSWER: When it has been created or edited in a non-Autodesk product.

That’s the version that Autodesk, the creator of the global dominating AutoCAD drawing program, would like customers to think. The DWG file format is the most commonly used CAD file format on the planet, with customers creating and storing billions of designs in this proprietary, yet industry pervasive format. Through decades of market dominance in the 2D world Autodesk’s AutoCAD and AutoCAD LT products have forced nearly all of Autodesk’s competitors to offer some level of DWG compatibility within their products. And it’s here, according to Autodesk, that the trouble starts, as they say poorly written third party DWG readers and writers are leading to file corruption within its customers.

However, DWG is a proprietary file format, owned, controlled and updated by Autodesk. The competitors have had to reverse engineer the format to include it in their products, to varying degrees of success. Autodesk’s own DWG libraries have been for internal or ‘close friend’ use for some time but Autodesk is not likely to openly publish the structure of the DWG format anytime soon to help competitors. This new move, the release of RealDWG is an interesting decision to licence the libraries to customers and selected developers, at a cost.

I talked with Mark Strassman from Autodesk on the subject of RealDWG. Strassman explained, “For the past few years we have had a component called Object DBX which is the internal component of AutoCAD that reads and writes DWG files, but it’s mainly an internal technology that’s used in all of Autodesk-based products and we have literally only licensed it to one or two other companies.

“At the same time we are seeing more end-users owning third-party products which they use in conjunction with our products, and since we included error reporting in AutoCAD 2004, we can actually see when and why people are having problems with our products. It turns out that a pretty fair percentage of those errors that we get back are people getting back corrupt or ill-formed DWG files. And we are getting tens of thousands of these instances.

“Developers are asking for access to ObjectDBX and some customers are saying they are having problems with the DWG file. It seemed that making the ObjectDBX more accessible was a step we could take. So we have enhanced the API (Application Programming Interface), we have full.NET APIs, and we have lowered the price, to the same as some of the competitive products out there ($5,000 up front, and then $2,500 a year). We have also enhanced documentation, with work examples, to make it easier to integrate with their applications and renamed it ‘RealDWG’, because ObjectDBX doesn’t mean anything to anyone. We have received hundreds of applications for this and developers are definitely excited and we have customers doing in-house development, for standards checking and data management. We have even had some competitors come and ask too, although in the contract it says it can’t be used for competition but we are talking to them as well. We may be able to share formats with competitors, we can hopefully work something out.”


The move is certainly a new venture for Autodesk, which has vehemently denied wanting to be in the ‘component’ business. But RealDWG sounds like a component technology that will be really useful to many developers and perhaps some of the higher-end AutoCAD users. The nod towards selected competitors is also of interest, although I suspect Autodesk would at least expect reciprocal access to their formats.

The move comes at a time when there is increasing competition for Autodesk’s DWG data. Indeed, Strassman explained, “It seems that a lot of interoperability these days, from third party companies to our competitors, are going for interoperability using our format, using DWG. So given that’s the case, we owe it to our customers to do what we can to make that more seamless.”

Speaking of competitors, SolidWorks has released a free tool for AutoCAD users to translate backwards and forwards between old and new AutoCAD formats (DWG Gateway), as well as giving away a DWG editor with its SolidWorks 3D modelling product. SolidWorks’ intention here is to try and stem the flow of AutoCAD revenue heading in Autodesk’s direction. There’s also a trend of Autodesk’s own customers buying more ‘cheap seats’ in the form of AutoCAD LT, despite Autodesk’s best efforts to hike up the price of that product. Perhaps it could be only a matter of time before 2D drafters look to even cheaper, perhaps non-Autodesk 2D tools?

These DWG initiatives wouldn’t have been possible if it wasn’t for the ready availability of reverse engineered DWG libraries from third party developers, mainly the Open Design Alliance. At this point, it’s worth going over some potted history.


2D CAD products have traditionally cost a considerable amount of money, I’d suggest that this is mainly due to AutoCAD’s dominance in the market, which has helped set the price for professional-level CAD. For most customers, moving to another solution requires retraining, there’s the legacy data issue and as the rest of the industry has standardised on AutoCAD, then it’s a no-brainer, AutoCAD remains dominant.

However, back in the 90s, one US-based developer, Softdesk, which had created most of its vertical developments on AutoCAD had started a secret development program called ‘Phoenix’ to create a clone alternative. The project was to reverse engineer AutoCAD to produce a low-cost AutoCAD clone, covering interface, features, functions and to include support for the precious DWG format. Autodesk bought Softdesk mainly for its AEC products but somehow the Boomerang project managed to be spun out from Softdesk at the time of sale and ended up with Visio, creators of products like Visio Technical (now owned by Microsoft). Visio then put renewed efforts to the development and delivered ‘IntelliCAD’, the first AutoCAD clone that sold for around 10% of the price of AutoCAD. Fortunately for Autodesk, it had released a cut down version of AutoCAD some years previous, and Autodesk used AutoCAD LT to head off IntelliCAD ‘at the pass’. However, at the time Autodesk also started a marketing campaign about ‘100% DWG’, a negative-style’ advert that reminded customers that only Autodesk’s products were guaranteed to be 100% compatible, implying that IntelliCAD, as it was reverse engineered and not an Autodesk product, was going to corrupt or omit important data. Added to this it didn’t help that IntelliCAD was rushed out, it was actually buggy and incomplete. It was a fairly bitter time between the two companies but ultimately IntelliCAD failed to make an impact.

Visio was eventually bought by Mic`rosoft but Microsoft had no intention of competing against Autodesk, and yet again the technology was bailed out of the mothership, this time to go it on its own as ‘open source’ software (like Linux).

Based on this technology, the non-profit OpenDWG Alliance (now called Open Design Alliance) was set up in1998 for CAD companies that needed to compete with Autodesk to pool their knowledge to improve the core reverse-engineered DWG libraries, together with the IntelliCAD Technology Consortium, where for a annual fee, application developers could take IntelliCAD (the AutoCAD clone based on the OpenDWG toolkit) and build DWG-based tools, without having to license any technology from Autodesk. Both organisations are still going strong, with the Open Design Alliance, now expanding to cover Bentley Systems’ officially sanctioned OpenDGN tool kit too. On that note, Bentley is a CAD competitor that has gone to extraordinary lengths to support DWG, with the V8 generation of MicroStation supporting DWG a as native format, should users wish to only work in DWG work mode.

Reaction to RealDWG

In response to Autodesk’s move, Evan Yares, President of the Open Design Alliance explained, “We assume that the RealDWG announcement is targeted specifically at the Alliance, and is intended to win-over some of our members. To the extent that Autodesk is successful in doing this, it could have a negative effect on the Alliance’s ability to serve its members. We are a non-profit consortium, and rely upon membership dues to fund the development of our libraries.

“Autodesk has cranked up its rhetoric machine, making vague allusions to broad problems with third-party DWG compatibility problems, and claiming great concern about this issue. If Autodesk wants to live up to its rhetoric, the solution is clear. All they need to do is publish the specification for the DWG file format.”

” At face value, RealDWG from Autodesk looks like a very late knee-jerk reaction to the OpenDWG concept. The very name implies that there is a non-real DWG “

Similarly, Arnold van der Weide, President of the IntelliCAD consortium (, was keen to point out the negatives of RealDWG. “At the IntelliCAD Technology Consortium we found that currently a majority of DWG files are not generated or edited by products from Autodesk anymore. This offers a challenge not only to the IntelliCAD Technology Consortium but in light of the recent announcement of RealDWG also to Autodesk. Unfortunately RealDWG isn’t available for developers who Autodesk regard as their competitors. With this Autodesk has missed an opportunity to set the one and only single industry DWG standard. At the IntelliCAD Technology Consortium we believe it is time that we work on this single standard which will benefit the whole CAD industry. I therefore call on Autodesk to publish the DWG file format and work with industry to set up an independent DWG certification entity to ensure the quality and consistency of the DWG file format.”


I’m not too sure about demands for Autodesk to openly publish the DWG file format from technology developers that exist to provide Autodesk’s competitors access to the format. Although Bentley has shown some way forward in ‘opening’ DGN there is a catch here and to gain access to those libraries you have to join the Alliance, a pre-requisite of which is to tell everything you know about DWG to the Alliance – obviously excluding Autodesk’s interest to join. However, there is nothing wrong with reverse engineering file formats and for customers this can be liberating when wanting to part company with a CAD vendor.

At face value, RealDWG from Autodesk looks like a very late knee-jerk reaction to the OpenDWG concept. The very name implies that there is a non-real DWG and the pricing is too close to the competition to be anything other than an attack on the many DWG reverse engineers. However, I also believe there could well be many cases when DWGs get passed around a number of Autodesk and non-Autodesk applications which may introduce some levels of corruption. Though here, data corruption is not unheard of within mixed Autodesk products alone.

It strikes me that Autodesk is indeed aware that DWG has become a major interoperability format, though mainly through reverse engineered toolkits and with RealDWG Autodesk may be able to wrestle back a certain amount of control, together with providing more predictable results for customers. The licensing appears to be vague enough to allow Autodesk a case by case decision on which competitors it will work with, although the few customers that want this functionality, together with the many registered Autodesk third party developers will welcome this move.

Autodesk is once again focusing on its formats with a new aggressive air to competition. There has been a big push of DWF against Adobe’s PDF for the ‘open’ engineering publishing format and now with RealDWG Autodesk is looking to protect the company’s considerable interests wherever the native file is read or written. Even if the DWG Alliance has good DWG readers, which it does, everyone would admit that having an equivalent tool from the original vendor would be preferable. Although, if you were competing against Autodesk, I don’t know many that would be too relaxed about relying on Autodesk as a component supplier.

The move certainly has caused a strong reaction from the DWG reverse engineering fraternity which sees RealDWG as a threat, Should members/customers sign up with Autodesk, then there’s less money to reverse engineer the DWG format, which everyone admits is an increasingly complex task. With this release, the cat is most certainly amongst the pigeons.


Leave a comment