# 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
Mars Surface levels should have ambient floating particles (dust motes, fine
sand) drifting across the screen to sell the atmosphere. Could tie into the
existing wind system — particles drift with the wind direction. Should be
subtle, low-alpha, and layered behind/in front of the player for depth.

## 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
Two new transition animations to complement the spacecraft fly-in:
- **Elevator** — Doors slide shut, brief pause (screen shake / rumble),
  doors slide open onto the new level. Good for base/station interior
  transitions (mars02 → mars_base, between generated station levels).
- **Teleporter** — Energy charge-up effect around the player, flash/warp
  distortion, player materialises in the new level. Good for cross-planet
  jumps or generated-to-handcrafted transitions.