When to use WPF and when to use other technologies

WPF and DirectShow

If you want to do capture (audio or video), or have your own DirectShow filter graph, you will have to code directly to DirectShow in WPF v1. You will then take the content and host it in WPF through HwndHost.

However, if all you want to do is play your own format, you can just provide a DirectShow CODEC for it, and then folks will be able to use the format through the Media element and fully integrate it as part of other WPF content, without limitations.

update 05/23/07 - here is an interesting posting of using WIC for getting DShow content into your WPF application Jeremiah Morrill's blog entry.

WPF and Direct3D

My simple axiom on the 3D front is:

if you already have domain knowledge in Direct3D (or OpenGL), you should stick with using Direct3D for WPF v1.

Now, to provide more context on my guidance. We make 3D a lot easier to use in WPF, and by a much larger developer audience than the one that uses 3D today. We also make it usable on the Web (in a xbap), we make it print, we make it remote, and we make it easier to integrate 3D with 2D, UI controls, and Documents (including as part of XAML). But, in using WPF, you give up a bit of the flexibility and direct hardware control that you get with the lower level APIs. We also manage your data (sometimes I refer to this as "managed graphics", to go along with managed code) and in doing so there is a bit of overhead, which costs you some performance (this is very dependent on the scenario, and we are tunning this code to reduce the cost based on scenarios that early adopters are sending in, so don't wait if you run into problems).

We did not optimize our architecture in this initial version for twitch games or high end scientific vizualization scenarios, so if you want to tackle something along those lines, give it a try and see if it meets your needs. Similar to the DirectShow case, once you get your content going, you use hwndHost to merge it with your WPF content.

Some scenarios for this involve providing a new UI for a Direct3D based application, or hosting a 3D modeler/editor within your WPF application.

WPF and GDI/GDI+

For those interested in factoids - GDI and GDI+ are part of our team, and some of the WPF developers/program managers/testers were part of those efforts many years ago (and many of us were involved in VML as well).

If you can't let go of raster ops, need 1-pixel wide lines, or need to load EMF/WMF files, then you will likely need to use GDI/GDI+, and then HwndHost. We are looking at how to tackle raster ops through effects, as well as provide scale invariant lines, in the future. WMF and EMF are a bit trickier, as we are trying to strike towards secure by default (even at the cost of functionality) and also because of expectations in terms of compatibility. I fully expect that some of you in the develop community will add value to the platform by developing EMF/WMF CODECs to be used within WPF applications.