islaApocalypse/Tools/Scripts
beezm c305fd6565 feat: blueprint v2 envelope — writer, dual-write, round-trip harness (terrain-water task 02)
v2 tagged-section container (D-030): raw ISLA magic + u32 version gate,
[u32 tag][u64 length][payload] sections — params (resolved generation
inputs incl. impact centre), heights f32, biomes u8, towns with the
highway-node flag, four road tiers identified by tag not position.

- BlueprintFormat.cs: the single tag/constant registry.
- BlueprintWriter.WriteV2: blueprint-typed, callable outside a
  generation run; generator and harness are both just callers.
- ExportMapData dual-writes: v2 under the primary seed name, legacy v1
  beside it as _v1.dat (safety net; removal is a future task).
- MapDataParser: LoadMapDataFromPath entry point; v1 parse body
  extracted intact as LoadV1 (v2 reader lands in the next commit).
- RoundTripHarness scene: load v1 -> write v2 -> load v2 -> semantic
  equality, headless, seconds per cycle.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-08-06 07:24:08 -04:00
..
MapGenerator.cs feat: blueprint v2 envelope — writer, dual-write, round-trip harness (terrain-water task 02) 2026-08-06 07:24:08 -04:00
MapGenerator.cs.uid baseline: working salvaged prototype on Godot 4.7.1 (pre-F1) 2026-08-05 01:45:41 -04:00
MapGenerator.md docs: bring all READMEs current with actual code (post-sweep-10 truth pass) 2026-08-05 05:23:58 -04:00
README.md docs: bring all READMEs current with actual code (post-sweep-10 truth pass) 2026-08-05 05:23:58 -04:00
RoundTripHarness.cs feat: blueprint v2 envelope — writer, dual-write, round-trip harness (terrain-water task 02) 2026-08-06 07:24:08 -04:00

/Tools/Scripts — generation logic

C# backend for the offline developer tools. Decoupled from the live server and client.

MapGenerator.cs

Generates the entire 2D blueprint. Roughly in order:

  1. Config — reads ServerConfig.json, which sets MapSize (8192 by default) and the crater radius. The MapSize = 4096 field initialiser is a fallback that is immediately overwritten.
  2. Topography — FastNoiseLite base height plus a mountain spine, minus a squircle distance falloff, giving a guaranteed island. Noise frequency is divided by scaleFactor (MapSize / 1024f) so terrain features stay the same real-world size at any map profile.
  3. Sea level and water — temperature-driven sea level; flood fill separates true ocean from inland lakes; a mainland fill guarantees one contiguous landmass.
  4. The crater — placed along the northern coast and carved to below sea level, but only out to 80 % of its radius, which guarantees a landbridge rather than severing the island.
  5. Biomes and towns — biome zoning by height and temperature; tiered town placement (Capitol, Hubs, Villages, Outposts, POIs) filtered by slope, water proximity and spacing.
  6. Roads — see below.
  7. Export — writes the .dat blueprint, then renders the PNG snapshot.

The road network

AStarGrid2D over the whole map at one node per pixel. Mountains are made expensive rather than impassable (1 + elevation³ × 400), water and the crater are marked solid.

  • Continental loop — highway nodes sorted by radial angle and connected in a ring.
  • Mountain branch — a spur from the loop to the snow hub.
  • County roads — Prim's algorithm daisy-chains remaining towns onto the network. Villages become Rugged roads, everything else Trails.
  • Abandon protocol — a town further than 8 % of the map from the network is skipped rather than pathed to, so one unreachable outpost cannot hang generation.
  • Smoothing — every path is decimated with RamerDouglasPeucker (tolerance 4.0) then smoothed with 4 Chaikin passes.

This is the project's dominant performance problem. At 8K the grid is 67 million nodes, and the weight-setup pass touches every one before the first path is requested. The await yields between stages cannot interrupt a single engine-side GetPointPath call, so a long path still blocks. Full regenerations frequently get abandoned.

The PNG snapshot

SaveMapSnapshot() builds an offscreen SubViewport in code rather than relying on the scene's layout, because Godot's UI layout engine will otherwise crush a 4096+ render down to the editor window size. A MapDrawProxy control re-issues the _Draw() calls into that viewport — GetImage() captures only the base texture and would otherwise miss the roads and towns entirely — and the code awaits two RenderingServer.FramePostDraw signals so the GPU has actually painted before the image is read back.

Road colours on the snapshot, useful for identifying a road: red = Highway, black = Branch, dark brown = Rugged, light brown = Trail.

Outputs

MapData_Seed_<seed>.dat and Map_Seed_<seed>.png, both to user://.

Rules

  1. No magic numbers. Distances, radii and thresholds derive from MapSize or scaleFactor, so the generator behaves identically at 4K and 10K.
  2. Respect the GPU. Anything exporting visual data must await the appropriate frame signals before reading pixels back.