I'm wondering if any consideration has been given to adding support for DNC charts
? These are MIL-STD-2407 VPF (Vector Product Format) charts
. The base file format is actually more suitable for charts than S-57 is (S-57 was never intended for full charts - it was originally intended only for chart update data).
Unfortunately, DNC has got a bad wrap among navigators in the Navy
here. For Canadian waters and some areas of American waters, the charts that were put into DNC format were done a long time ago and were converted by hand from raster charts
(ie: some summer student at a computer overlaying vector chart objects on top of the positions shown on raster charts). So the chart data is terrible and even dangerous to navigate off of. This is the case for almost all Canadian DNCs and most American ones that are for areas where there are no S-57 charts (some Alaskan waters for example).
In any case, despite the fact that some of the DNC charts are low quality, the file format is excellent, and the new DNC charts coming out now are excellent quality. Supporting DNC would be great for OpenCPN