One planet, one coastline, everywhere
Tirawen is one continuous torus-shaped world, about the size of the Moon, with roughly 37.9 million square kilometres of surface, three major continents, one connected ocean, and hundreds of islands worth sailing to. Both axes wrap, so travelling far enough in any direction brings you back around.
The important part is consistency. The world you see from orbit is the same world you walk across on foot. A bay seen from far away is still there when you arrive, and the coastline never shifts between the map and the ground under your boots.
Terrain is built from a deterministic system: every point's height comes from its position, so the same place always produces the same result. That terrain logic lives in three places, Python (the reference), Rust (the server and the in-engine generator), and GDScript (the client), and the build checks they agree, because if one thinks a spot is land while another thinks it is ocean, gameplay breaks.
The coastline gets its own protection: fine detail fades out near sea level, so noise cannot turn ocean into land or land into ocean. Erosion runs across the whole wrapped planet rather than per chunk, carving real drainage. A floating-origin system shifts the active area back near zero before large-coordinate precision degrades.
- Topology: flat torus (both axes wrap). 6,150 km per axis, roughly 37.9 million km² of surface.
- Sea level 0 m (fixed). Three major continents, plus islands and islets.
- Generator parity across Python, Rust, and GDScript, gated in CI: 3,000,000 cross-build samples, zero mismatches.
- Coastline gate: 2,300,000 boundary cells checked, zero land/ocean flips.
- Erosion: planet-wide hydraulic flow accumulation, torus-wrapped, ocean cells excluded.