Tom Arah explains why the new Windows Presentation Foundation in Windows Vista is set to revolutionize computer-based design.

Recently I’ve looked at the history of computer-based design for both print and screen. It’s been a strange story with many twists and turns...

resulting in today’s current state of play in which Adobe, which effectively started the whole ball rolling back in 1985 with its invention of the PostScript PDL (page description language), has come to totally dominate. In particular, through its recent takeover of Macromedia, Adobe is now in the position to merge today’s three most important electronic design media – Acrobat PDF, Flash SWF and Web HTML - to create its new “Apollo” platform (since renamed to AIR the Adobe Integrated Runtime). This “Adobe Engagement Platform” promises the best of all worlds – highly designed documents, dynamic multimedia, rich interaction, advanced programmability and live content – provided through both browser-hosted internet applications and local desktop programs.

In Adobe’s Engagement Platform the future of design is a cross between interactive desktop application, live web site and rich document

With its current combination of underlying technologies and best-of-breed authoring applications it might look as if Adobe’s position is unassailable and that the company will single-handedly determine the future of cross-platform and cross-media design. However there is one other software giant with the developers, resources, vision and sheer market clout to take on Adobe on its own territory - and that is precisely what Microsoft is planning to do with the long anticipated and much delayed launch of Windows Vista.
What makes Vista so significant for designers is its next-generation screen and print display subsystem, Windows Presentation Foundation (WPF) previously known as Avalon. Whereas Windows XP’s GDI+ simply extended Windows’ longstanding GDI (Graphics Device Interface), WPF represents a total rethink and rewrite with a new focus on design in the round rather than just graphics handling. As such it introduces a whole host of crucial advances such as the core re-routing of all presentation tasks through DirectX to offload processing onto the graphics card and away from the CPU wherever possible.
The biggest change in WPF is even more fundamental, as Microsoft at last provides true vector-based screen rendering – just as Adobe attempted to provide with Display PostScript over 20 years ago. The resulting resolution and device independence finally enables WPF to offer true “DPI scaling” which means that as screen pixel density increases, vector icons and graphics and, crucially, text will all improve in quality rather than shrinking in size as is the case currently. This is hugely important as it will enable a designer to specify a particular size safe in the knowledge that that is what the end user will actually see. Or rather that this optimal version is what they will see when viewing at 100% and with the correct DPI setting, as the end user will always be able to override these settings for their own viewing comfort – a factor that is crucial for ensuring in-built accessibility.