Hi Paul, 2012/8/31 Paul HAYDON <cadmana...@live.com.au>
> I've recently used Quantum GIS (QGIS) to create a region about my GPS > routes so as to capture the fuel stops (for example, within 10km of my > chosen path). I would think if someone could establish the coastline as a > perimeter, then it could be generated by the same means. > Yes, the offset/buffer can be calculated with QGIS. I've done this before, unfortunately I didn't take any notes at that time so I would have to find my way again. But the key problem is that the boundary is not calculated from the coastline directly. Instead of the coastline an artificial line called baseline is used (cf. [1]). Bascially this cuts off a couple of bays - (the black areas in [2]). So looking at [2] the baseline (and border) run from the northern tip of Fraser island straight west towards Bundaberg. If you would to the calculation from the coastline the border would rather have a bend to the south inbetween. That's why I personally would prefer trying to get import permission as and only use the coastline as a backup solution. > I'm not sure what distance the territorial waters go to, > That's the easy part: It's 12 nautical miles (from the baseline). Anyway, I'd be happy to collaborate on this if you think it will help. > You're definetly welcome! Michael -------- [1] http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dmaritime [2] http://www.ga.gov.au/image_cache/GA3746.pdf
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