# TODO

## ~~Distance-based sound effects~~ ✓
Implemented: `audio_set_listener()`, `audio_play_sound_at()` with linear
attenuation and stereo panning. Used by enemy death, asteroid impact, and
powerup pickup.

## ~~Spacecraft art and entity~~ ✓
Implemented: spacecraft PNG spritesheet (5 frames, 80x48 each), full entity
with state machine (FLYING_IN → LANDING → LANDED → TAKEOFF → FLYING_OUT →
DONE), engine/synth sounds, thruster particles, level intro sequence with
deferred player spawn.

## ~~Large map support (5000x5000)~~ ✓
Audited and fixed all engine bottlenecks for maps up to 8192x8192:
- `MAX_MAP_SIZE` constant (8192) replaces hard-coded 4096 caps in tilemap
  loader and editor resize. Tile layers allocate fine at 5000x5000 (~143 MB).
- Dynamic line reader in `tilemap_load()` replaces fixed 16 KB `fgets` buffer;
  handles arbitrarily long tile rows without truncation.
- `MAX_ENTITY_SPAWNS` raised from 128 to 512; `MAX_EXIT_ZONES` from 8 to 16.
- Entity distance culling: `entity_update_all()` skips entities beyond 2×
  screen width from the camera; `entity_render_all()` skips entities outside
  the viewport + 64 px margin. Player, spacecraft, and drone use
  `ENTITY_ALWAYS_UPDATE` flag to opt out of culling.
- Editor flood fill replaced with scanline algorithm — O(height) stack usage
  instead of O(area), safe for very large maps.
- Verified: tilemap rendering already viewport-culled, physics queries are O(1)
  local tile lookups, float precision fine up to ~1M pixels (62 K tiles).

## ~~Spacecraft at level exit~~ ✓
Implemented: `spacecraft_spawn_exit()` with `is_exit_ship` flag. Proximity
trigger in `level.c` spawns exit ship when player is within ~2 screen widths
of an exit zone. Ship flies in, lands near exit. Player overlaps landed ship →
player deactivated, ship takes off, camera holds still, level transition fires
after ship departs (SC_DONE).

## ~~Asteroid refinement~~ ✓
Implemented: base speed 120→200, accel 200→350, respawn 3→6s, stagger 0-3→0-8s,
random horizontal drift (±60 px/s), moon level reduced from 24 to 8 asteroids.

## ~~Moon campaign: 3 levels with spacecraft transitions~~ ✓
Implemented: 3 moon levels connected by spacecraft takeoff/landing sequences.
- **moon01.lvl** (1000 tiles) — Exit triggers spacecraft, transitions to moon02.
- **moon02.lvl** (200 tiles) — Crater fields, tighter platforming. Spacecraft
  intro, 7 asteroids, unarmed. Exit to moon03.
- **moon03.lvl** (150 tiles) — Dark side, hardest moon terrain. Spacecraft
  intro, 5 asteroids, unarmed until gun powerup near exit. Exit to level01.
- **level01.lvl** — Space station with spacecraft landing intro (arriving from moon).

## ~~Level generator: height zones (verticality)~~ ✓
Implemented: tall level support (46 tiles, two screens) with height zones.
- Camera vertical look-ahead (30px lead when player moves vertically > 50 px/s)
- All segment generators (`gen_flat`, `gen_pit`, `gen_platforms`, `gen_corridor`,
  `gen_arena`, `gen_shaft`, `gen_transition`) accept `ground_row` parameter —
  platforms, enemies, and hazards are placed relative to the zone's ground level
- `SEG_CLIMB` connector segment type: vertical shaft with alternating platforms,
  wall openings, optional moving platform and enemies, bridges height zones
- `levelgen_generate()` assigns zones per theme: Surface → LOW (row 43),
  Base → HIGH (row 17), Station → alternates. `SEG_CLIMB` auto-inserted at
  zone boundaries. Single-theme levels stay at standard 23-tile height.
- Station generator unchanged (23 tiles, corridor envelope constrains)
- Tall test level: `assets/levels/tall_test.lvl` (40x46)

## ~~Jetpack boost blue flame effects~~ ✓
Implemented: `particle_emit_jetpack_boost_burst()` (electric blue core +
blue-white flare, 18 particles mixed into regular burst) and
`particle_emit_jetpack_boost_trail()` (blue sparks + pale blue wisps,
3 particles/frame). Both activate only when `jetpack_boost_timer > 0`.
Burst fires on dash start, trail emits each frame during dash.

## ~~Pause menu~~ ✓
Implemented: extracted bitmap font from `editor.c` into shared `engine/font`
module (`font.h`/`font.c`). Added `MODE_PAUSED` game state to `main.c` with
semi-transparent overlay, menu items (Resume / Restart / Quit), up/down
navigation, confirm with jump/enter. Restart reloads file-based levels or
regenerates procedural levels.

## ~~Laser turret hazard~~ ✓
Implemented: `ENT_LASER_TURRET` entity with state machine (IDLE → CHARGING →
FIRING → COOLDOWN). Beam uses per-pixel raycast via `tilemap_is_solid()`.
Player damage via point-to-line distance check. Rendering with
`SDL_RenderDrawLine` and perpendicular offset for beam thickness.
Two variants: `laser_turret` (fixed, aims left) and `laser_turret_track`
(rotates toward player at 1.5 rad/s during idle/charge, locks on fire).
Both registered in entity registry with editor icons.

## ~~New enemies: Charger and Spawner~~ ✓
Implemented in `enemy.h`/`enemy.c`:
- **Charger** — Ground patrol → ALERT (0.5 s telegraph) → CHARGE (150 px/s
  rush) → STUNNED (0.8 s on wall hit, reverses). 2 HP. Detects player in
  horizontal line-of-sight within 200 px.
- **Spawner** — Stationary. Spawns grunts every 4.5 s (max 3 alive via
  `count_alive_grunts()`). Pulses before spawn. 3 HP, destructible. Purple
  color scheme. Both registered in entity registry with editor icons.

## ~~Mars campaign~~ ✓
Implemented: three handcrafted levels, a dedicated Mars Base generator, and
Mars themes in all generic segment generators.

### Handcrafted levels
- **mars01.lvl** (250×23, Mars Surface): low gravity (370), wind, wide-open
  red terrain, charger + grunt enemies, spacecraft intro. New
  `mars_tileset.png` and `PARALLAX_STYLE_MARS` (salmon sky, red mesas, dust).
- **mars02.lvl** (40×46, Mars Base): normal gravity (700), tall vertical
  corridors with narrow passages, turrets, laser turrets (fixed + tracking),
  spawners, chargers, grunts. Exits to `generate:mars_base`.
- **mars03.lvl** (30×23, Boss Arena): heavy enemies (spawners, chargers,
  laser turrets), exits to `generate:station`.

### Mars Base dedicated generator
- `levelgen_generate_mars_base()` with 6 custom segment types: Entry (safe
  start), Shaft (vertical with alternating platforms + laser turrets),
  Corridor (narrow horizontal passage), Turret Hall (three-level laser
  gauntlet), Hive (spawner room), Arena (tall multi-level combat).
- 46-tile tall levels, Mars tileset, interior parallax, 700 gravity.
- Depth scaling: 6→7→8 segments, difficulty 0.5→0.7→0.9.
- After 2 generated levels, exit points to mars03.lvl (boss arena).
- `generate:mars_base` exit target handling in main.c with `s_mars_depth`.

### Mars themes in generic generators
- All 7 generic segment generators (`gen_flat`, `gen_pit`, `gen_platforms`,
  `gen_corridor`, `gen_arena`, `gen_shaft`, `gen_transition`) place
  Mars-specific enemies (chargers, laser turrets, spawners) when the active
  theme is `THEME_MARS_SURFACE` or `THEME_MARS_BASE`.

### Music
- `kaffe_og_kage.ogg` used for all Mars levels (handcrafted + both generators).

### Level chain
- moon03 → mars01 → mars02 → generate:mars_base (×2) → mars03 → generate:station.

### Bug fixes (this batch)
- Deterministic seed on generated level restart (`s_gen_seed` snapshot).
- NULL checks on calloc in `charger_spawn`, `spawner_spawn`, `laser_spawn_internal`.
- Charger charge timeout (2 s max) prevents infinite charge on flat terrain.
- Removed no-op `flags |= 0` in spawner_spawn.
- Jetpack fuel pickup preserves recharge progress instead of resetting timer.
- Makefile web-serve: removed `2>/dev/null` so real errors are visible.
- `s_mars_depth` and `s_station_depth` reset when game loops back to beginning.
- Added `gen_bg_decoration()` call to Mars Base generator.

## ~~Editor: level select should also load into game~~ ✓
Implemented: shell dropdown calls `game_load_level()` (exported from `main.c`)
which defers a level load into MODE_PLAY on the next frame. Tears down the
current mode (editor or play), loads the selected `.lvl` file, and seeds
`s_edit_path` so pressing E opens the same level in the editor.

## ~~Mars Surface atmosphere particles~~ ✓
Implemented: `particle_emit_atmosphere_dust()` emits ambient dust motes each
frame on Mars Surface levels (keyed on `PARALLAX_STYLE_MARS`). Three
sub-layers for depth: large slow "far" motes, small quick "near" specks,
and occasional interior spawns to prevent edge seams. All particles drift
with the wind system via `gravity_scale` — wind pushes them across the
viewport. Reddish-tan color palette with per-particle variation. Low drag,
long lifetimes (3-7 s), subtle alpha fade. ~2-3 particles/frame at 60 Hz,
well within the 1024-particle pool budget.

## Skip spacecraft transition for non-surface levels
The spacecraft fly-in animation should only play on surface levels (moon01,
mars01, etc.). Interior/base levels (mars02, mars03, generated mars_base,
generated station) should skip it — the player is already indoors.

## ~~New level transition styles: elevator and teleporter~~ ✓
Implemented: `src/game/transition.h` / `transition.c` module with two-phase
transition state machine (outro on old level → level swap → intro on new level).

- **Elevator** — Two horizontal doors slide inward from top/bottom (0.6 s),
  hold closed with screen-shake rumble (0.3 s), then slide apart on the new
  level (0.6 s). Smooth ease-in-out motion, dark gray industrial color,
  bright seam at the meeting edge. Used for base/station interior transitions.
- **Teleporter** — Scanline dissolve: 3 px-tall horizontal bands sweep
  across the screen in alternating directions with staggered top-to-bottom
  timing (0.5 s), then white flash (0.15 s). Intro reverses the sweep
  bottom-to-top (0.5 s). Uses `teleport.wav` sound effect.

New `MODE_TRANSITION` game state in `main.c` pauses gameplay during the
animation. Level-load dispatch extracted into `dispatch_level_load()` helper,
called both from instant transitions and from the transition state machine.

New `.lvl` directives `TRANSITION_IN` and `TRANSITION_OUT` with values
`none`, `spacecraft`, `elevator`, `teleporter`. Parsed in `tilemap.c`,
saved by editor and level generator dump. All three procedural generators
(generic, station, mars_base) set `TRANS_ELEVATOR` for interior themes.
Handcrafted levels updated: mars02, mars03, level01, level02.