Adding 3D Printing Support to WinRT and Desktop Applications
As mentioned before, Windows 8.1 will include support for 3D printers. In the image below you can see a basic overview of the 3D printer pipeline. Most of the work needed to turn a model into instructions of the printer is done by various pipeline modules in the driver itself. This includes reading the 3MF spool file format, model analysis and repair, slicing into z layers, and creating tool paths.
Application developers will need experience working with DirectX, specifically Direct3D. A sample application is available that demonstrates using the IPrintDocumentPackageTarget interface to create a 3D print job. While everything is largely the same downstream, the way you get an instance of this interface differs between WinRT and desktop development. WinRT applications need to implement the IPrintDocumentPageSource interface while desktop applications call CreateDocumentPackageTargetForPrintJob. With that an IXpsOMPackageWriter3D can be obtained and the 3D mesh that represents the model is written.
Much like a normal printer, the developer of the 3D printer driver may expose an advanced settings dialog with device specific options. This is where the user would be given the opportunity to change the print quality, product density, add supports, etc. The driver will need to provide a separate UI for WinRT and desktop applications.
3D print drivers are part of a new category known as PrintFax.Printer.3D. Windows 8.1 will support both the USB Printer Interface (class 7, type 3) and Serial over USB. The latter is used for legacy hardware and only allows v3 printer drivers. The USB Printer Interface supports v4 printer drivers, which are necessary for the aforementioned advanced settings screen and the ability to auto-install software from the Windows store.
The full driver SDK for 3D printers is not part of the normal Windows Driver Kit. To obtain it you need to write to firstname.lastname@example.org. There is no word on the cost for this kit. The WDK does have a quick start template for v4 print drivers.
For more information watch the 3D Printing with Windows video on Channel 9.