- runtime: HEADLESS_FRAME_PATH, STICK_DEADZONE / STICK_LEFT_X/Y, key and
byte codes as char literals throughout (`k == 'w'`, `fill(rt_map, ' ', …)`)
- ludic.gameplay/stats: drop the duplicate `stat_field` (it answered "atk"
for every build stat); Stats.base uses stats_field_name
- ludic.shooter: compare aim modes and fire patterns with AimMode.* and
WeaponPattern.* instead of raw ints; STICK_RIGHT_X/Y
- ludic.npcai: DecisionMade / brain_set_state use AiState.*
- examples/games/menu.ludic uses Font.load / Ui.* with FONT_PATH and
BACKDROP named; strings.ludic header says what it prints
- whole tree: `x = x + 1` → `x += 1` (single-term right-hand sides only),
`0 - x` → `-x`, ASCII codes → char literals; every .ludic and every
```ludic fence reformatted with the fixed formatter (whitespace only)
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Grid.* operates on the Map tilemap (Map.size/Map.row): a cell is passable unless
it is out of bounds or holds the caller's `wall` tile (a char code, e.g. '#'), so
any impassable glyph works. Everything is integer and deterministic.
- Grid.line(x0,y0,x1,y1) -> []Cell Bresenham line cells (LOS/raycast base)
- Grid.blocked(x,y,wall) -> bool the shared passability test
- Grid.line_of_sight(x0,y0,x1,y1,wall) unobstructed straight line?
- Grid.flood(x,y,wall) -> []Cell 4-connected reachable region (BFS)
- Grid.a_star(x0,y0,x1,y1,wall) -> []Cell shortest 4-connected path (A*,
Manhattan heuristic), empty if unreachable
The engine (runtime/native/grid.ludic, ~150 lines of Ludic, C-free) is spliced
into a game via core.ludic since it reads the tilemap runtime; returned Cell
slices are ordinary Ludic slices (`len` / `[i]`; each cell has `.x` `.y`).
Pathfinding lives under Grid rather than a `Path` namespace — that name is
already the filesystem-paths library (#10).
Verified against Python references: a 1500-case fuzzer over random maps agrees
exactly on A* path length (optimal, == BFS), flood-fill count, and line-of-sight.
examples/library/grid.ludic asserts the behaviour and is wired into `x test`
(now 61 passed); docs: a Grid section + 5 per-symbol pages, inventory/coverage
green. Seed reseeded; the C-free bootstrap fixpoint holds.
Scope: this lands the Grid.*/pathfinding half of #24. The ECS Query.* helpers
(count/first, and nearest/within which want a runtime spatial index) remain the
tracked follow-up the issue calls out as blocked.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>