tehAon’s RWG Islands – Island Maps from Random World Generation (Server-Side)

First version.
- **Bridges** (a Bridges row under Causeways, on by default): each causeway rises on ramps of 1 in 8, eased at both
ends, to a concrete span over a gap cut to the sea bed in mid-channel - 10 blocks of clear air over the water, so
boats pass under. The causeway runs dead straight through the bridge zone, at the span's angle (spans come in
15-degree steps). Ramps are painted as road. Checked in a 3.4 client: water under every deck, joints flush, a
motorcycle and a 4x4 across, parapets that stop a bike, a swim through the middle opening.
- **Island worlds from random world generation**: sea on every side of the map, with a shore of bays and
headlands. The game can already do this - one world in sixteen - but has no setting for it.
- **Several islands**: `islands="2"` to `"12"` cuts channels through the land. Towns, traders and
wilderness places are planned round the water by the game itself; every island tested got towns and
at least two traders.
- **Causeways**: a strip of dry land across enough channels to reach every island, each with a road
over it. `causeways="false"` leaves the islands apart.
- Settings in `RWGIslands.xml`: `islands`, `causeways`, `coast`, `channel`.
- **Islands stand in open water.** The channels were one width all along (180 m on an 8 km map), so
several "islands" read on the map as one landmass cut by rivers - Kenny's words on seeing the preview.
A channel is now narrowest where its causeway crosses and opens out away from there into open sea,
and the narrows themselves are wider (330 m at 8 km). About half the map is water where a quarter
was. Beside a causeway the water is held to the channel's width, so the crossing stays short: two
headlands reaching for each other. `open="0"` in the file gives the old canals back;
`tools/planmap/run.sh` draws any plan without the game.
- Fixed with it: a causeway now runs the whole way between its two islands. It used to be drawn only
where those two were the nearest pair, which the wider …