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I second that! And not only that -- I would also want obstacles to be considered in a semicircle before the beginning of the route and beyond the end of the route.
I want to this both from a strictly safety point of view and from a regulatory point of view. When you fly VFR in darkness you are required (in the en-route phase) to have a minimum altitude of 1000 feet above the highest obstacle within 8 km from the aircraft's estimated position. There is no exception for the start or end points of the route nor for the outside of a turn. Similarly, if I fly in mountainous terrain, I will want a safety margin I can rely on in all directions.
As it is, I don't really trust SkyDemon's MSA calculation, both because of known limitations and because I don't really understand exactly how it works. Considering obstacles at both sides of each leg and within semicircles at both ends of each leg would both satisfy regulatory requirements and be very easy to explain.
I seem to recall from a discussion some years ago that Tim said checking for obstacles within (semi)circles were computationally difficult. If that is still the case, I would be happy if SkyDemon simply used half-squares before and after each leg. Since a half-square is larger than a semicircle some obstacles could be considered that shouldn't be, but the area would really be larger only by a small amount and it is better to err on the side of caution.
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