What I'm looking for 99.9% of the time is a lot simpler; just what part of a face is shaded at any time between 0900 and 1600.
Effectively, what the result would be if one used TIG's Shadowprojector for every minute of that time, (realistically, every half hour or even hour is plenty to connect the corners later) then combined all the results into a single shadow. Ideally, this would then be expanded to include the entire year, but I tend to find that doing the whole thing for the solstices, then a quick check of morning and evening on the equinoxes gives a pretty solid result, so I'm not averse to doing that.
One benefit of the all-or-nothing approach is that once a point has been determined to be shaded, it no longer needs to be checked for any remaining times in the test period.
Is there a way to pare things down in the settings of Chronolux to do this fairly quickly? Sometimes the areas can get rather large, so any savings is useful.