Comment 262 for bug 260918

Fwink creates a NullRenderer. It adds it to the filter graph. On the CaptureGraphBuilder2, it calls RenderStream(), asking it to link the preview pin to the the default renderer. Then it calls RenderStream() again, asking it to link the output pin to the NullRenderer. Finally it adds the sample grabber in front of the NullRenderer, allowing it to take photos.

Since the camera doesn't have a preview pin, CaptureGraphBuilder2 must support the SmartTeeFilter which creates one by duplicating the output pin. Wine's doesn't have that filter. Furthermore, Wine's CaptureGraphBuilder2 doesn't even link the pins correctly. With my patch above, it at least links both to the NullRenderer, allowing Fwink to take photos, but not show preview video (since that needs the SmartTeeFilter).

Those that believe Fwink worked before must have been using native qcap?