Demo: Read a ChemDraw File
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For background, see previous D-F articles on the ChemDraw CDX file format and the CDX HexDumper utility.
Being able to visualize the contents of arbitrary CDX files this way is an important aid to debugging and a prerequisite to developing full-featured graphical display capability.
It's a pretty safe bet that any organic chemist who has written a report, submitted a journal manuscript, or filed a patent has used ChemDraw. As a result, ChemDraw files are everywhere in chemistry.
If you've spent any time watching how chemists work, the need to manipulate CDX files may be obvious. Even so, I'd like to offer a specific example taken from a recent project that illustrates that the need to work with CDX files can come from some unlikely places.
Reagents is iOS Organic Chemistry reference app that I co-developed with James Ashenhurst. It makes heavy use of ChemDraw CDX files to display structures and reaction schemes.
These structures and reactions schemes are automatically pre-rendered through AppleScript automation of the ChemDraw application. Although this works, it's far from optimal. For example, Reagents runs on iPad 3 (retina) displays. To prevent pixellation, our horizontal resolution measures in the thousands of pixels. The large size of the resulting images means more storage space and longer download times. But the biggest problem lies in the fact that every time we make changes to these ChemDraw files, we must regenerate the corresponding raster image.
It would be so much better to dynamically render these ChemDraw files inside an iOS UI element such as UIWebView.
We'd also like to do interesting things with the ChemDraw files themselves. I won't spill the beans here, but suffice it to say that if we're successful you'll be seeing one or more new iOS apps that repurpose the Reagents content in some interesting ways.
Given the centrality of the CDX file format in chemistry, we're starting there first.