I’m still working on Line-Of-Sight (LOS) and suspect I will be doing so for some time to come.
I have made a lot of progress, however I’m trying to produce results that approach real-world fidelity and this takes time.
The task has turned out to be more difficult than originally envisaged. This is because the terrain model used by the map isn’t real world – it is heavily quantised into flat contours rather than real-world slopes and undulations.
As a result, I’m having to tweak the LOS routines so that even with the limitations of the terrain modelling they will still produce reasonable results.
Here are some screenshots of the progress so far – red zones are shadow zones that cannot be seen by the observer.
Two screen shots of the Granicus map. These show the effects on Line-Of-Sight as an observer – the red circle – moves Southward towards the hills. (Click for a larger version).
Here is a close up of the hills where the observer is approximately 2 km away. Note that there are still shadow zones, but on the whole the observer can see a fair proportion of the hill. (Click for a larger image)
As the observer gets nearer to the hill – marked by the red circle – the visibility of the hill actually drops! This may seem a little odd, but I have a lot of hill walking experience (see my other blog at http://ukbackpacker.wordpress.com) and this does bear out my experience. For a close up observer to see more, the hill contour slope would need to be more consistent as it rises or be of a concave shape – neither of which is the case here. (Click for a larger image)
Two screen shots of the woods as the observer moves Southward. These woods have been set with a density that allows one to observe units up to 100 mtrs in. This is configurable on a woods by woods basis. (Click for a larger image)
There is still a lot of work to do, but I am quite proud of it so far, especially the way it models the closing down of LOS as one approaches a hill – I’m not sure that I have seen any other wargame model this! 🙂