Howto edit ArmA 3 water / ocean depth heightmap elevations.
See Water Color for detailed info how ArmA 3 water system works.
Buldozer loads way too long with large satellites resolutions, without layers dir its fast but that is a moot point as the ground is pure white where you cannot see details. It is horrible to edit large ocean depths and especially long coastlines. However buldozer is the only tool you can really fine tune the “final arma3 result” for coastlines.
You should do the large scale editing with L3DT and only do final touches in buldozer.
L3DT is very nice to edit large areas of ocean depths, but is pretty useless for precise coastline work because you cant tell precisely where the satellite and water is.
Precisely? Well talking about arma3 buldozer precisely here of course.
You can however do “good enough” work with L3DT texture map view using even 20 pixel brush gets you acceptable results (compared to loading heightmap into buldozer for half an hour, heh).
L3DT Texture Map needs to be power of two sizes! for example 2867 x 2867 resolution does not work as it adds ugly stretch marks, but 2048 x 2048 works OK. Do not use odd resolutions.
Howto lower SRTM 0m ocean elevations to -5m.
Use 10 pixel brush when lowering elevations near the coastline, you can do pretty accurate work with it but still maintain at least some speed of how much ocean you cover. Brushes like 25 pixel or above are bit too large for near coastline work. Use heightfield tools → smooth, to make the edge between -5m and -50m smoother as even though its underwater and possibly rarely seen in-game, its still great to have it smooth instead of 45 meter hard drop. Smooth tool 10 pixel brush and nCycles of 5 should be quite nice.
Lower the initial coastline to maybe like -3m or -5m shallow water, do this with 10 or 20 pixel brush, then take mass 100 pixel brush and lower the main ocean further from the coast into -50m depth or more.
Deep ocean work is best done with as large brush as your computer can handle, in our AMD Athlon FX-4170 4.2Ghz Quad Core system anything above 100 pixel brush will start to lag so much that it is not enjoyable to edit anymore.
make satellite texture with good colors for buldozer use, not sure what these colors would be but at least dark blue ocean color for underwater elevations is bad because its hard to see (difficult to explain).