# Unity Tower Defense — Project Roadmap

## Purpose

The **forward-looking plan**: what's done, what's next, and the sequencing. Current-state architecture and the full list of implemented systems live in [`Project_Context.md`](Project_Context.md) — read that first for "how things work today." This document focuses on direction and remaining work.

Last substantial update: 2026-07-14.

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## The game

A **co-op tower-defense / roguelike hybrid** (up to 9 players, Steam). Wintermaul-style maze defense — build towers to snake enemies through your zone (shared lives, per-player gold) — fused with a roguelike draft.

### Roguelike core loop

All players start with the **same three towers** — **Basic Arrow** (ground+air, single-target), **Siege Cannon** (ground-only, splash), **Wall** (no damage, near-free, maze-shaping). Players grow a personal **deck/"build"** through a **3-option draft** at match start and after every wave. The draft is free; players can also spend **gold to buy extra rolls**, creating the central tension: spend gold on towers (your maze) vs. spend on rolls (your build).

**Five draft choice archetypes:**
1. **New tower** — add a tower to your buildable arsenal.
2. **Tower upgrade** — *systemic first* ("all towers of damage-type/projectile-type X gain Y", "unlock Lv.2 across the deck"); per-tower trees only later if needed.
3. **Enemy debuff** — temporary (weaker / slower / downgrade a tier); cost scales with duration.
4. **Builder ability** — active, targeted, in-wave, cooldown-based (e.g. Call Lightning, Haste, Stasis Trap).
5. **Relic quest** — opt-in secondary objective granting a powerful passive Relic.

### Locked design decisions
- Draft is **free** at match start + after each wave; a gold **shop buys extra rolls**, available any time *(provisional — may change)*.
- **Per-player** decks/progression (each player drafts independently).
- Tower **upgrades are systemic-first**.
- **Draft pacing:** the prep phase before each wave is the draft window; unpicked drafts **auto-resolve at prep end** so no slow/AFK player stalls the group.
- Draft options are **authored ScriptableObjects** drawn by **weighted random**.

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## Status at a glance

**Done & merged:** functional match loop end-to-end, HUD, lobby + race selection, economy, enemies + A* pathfinding, **flying enemies + air-targeting**, **per-player tower deck** (keystone #1), **draft Slice 1** (spine + "new tower"), **TowerRegistry removal** (towers replicate by `TowerTypeId`), **per-tower construction-phase build visuals**, **ground-seating from mesh bounds**, **Tesla Coil tower** (Electric + AllInRange + arc VFX with real flash/impact lights).

**Done, on branch `tower-sell` (pushed to origin; NOT yet merged to `main`):** **Tower Sell** — owner-gated Sell action, refunds `SellRefundPercent` (default 75%) of invested gold, the **Wall refunds 100% while un-upgraded**, refund excluded from round income, coin **VFX** (artist-authored emissive mesh-particle `FX_SellTower`, with a `CoinBurstVfx` code-gen fallback) + rustle **SFX**. Also a **budgeted enemy re-path scheduler** in `PathfindingService` that removes the ~0.5 s frame hitch on any maze change (sell/placement) with a full wave present, plus a batched footprint un-stamp and the NGO `RequireOwnership`→`InvokePermission` deprecation cleanup. Verified in-engine 2026-07-14.

**In progress (branch `feature/post-processing`):** project-wide **grimdark post-processing** grade + HDR; Tesla arc lighting polish. *(This branch was fast-forwarded onto the Tesla work; commit the post-processing assets + the `TeslaArcVisual` light additions.)*

**Paused:** in-match Paint system (overlaps with systemic upgrades).

**Next:** draft **Slice 2 (systemic upgrades)**; the **grimdark lighting pass** (see Part C); author 2 more new-tower designs.

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## Part A — Roguelike build-out (current focus)

### A1. Per-player tower deck — ✅ DONE (merged)
Towers are unlocked per player, not globally available. See [`Project_Context.md`](Project_Context.md).

### A2. Draft spine + "new tower" (Slice 1) — ✅ DONE & merged
Server generates 3 weighted options per player each prep phase; players pick via a non-modal HUD overlay; unpicked auto-resolve at prep end; gold "Buy Roll" purchases extra rolls. Only choice type is **New Tower** (grants into `PlayerTowerDeck`).

### A3. Draft Slice 2 — systemic tower upgrades — ⏭ NEXT
- Add an upgrade `DraftOption` subclass applying **systemic** modifiers: "all towers of damage-type X gain Y", "all projectile-type X …", "unlock Lv.2 across deck".
- **Reconcile with `PlayerBuffManager`.** The existing gold-bought buff stack (global Damage/AttackSpeed multipliers) is the natural underlying apply mechanism — generalize it to type-filtered modifiers and make the draft (not the standalone buff menu) the entry point. Decide the fate of the old buff menu here.

### A4. Builder active abilities (draft choice #4)
New in-wave, targeted, cooldown ability system (Call Lightning, Haste, Stasis Trap). New `DraftOption` subclass grants an ability to the builder; needs input/targeting + cooldown UI. Some builders may start with an ability unlocked.

### A5. Relic quests (draft choice #5)
Secondary-objective tracking ("place 50 towers in 5 min", "leak 0 for 3 waves") that, on completion, grants a powerful passive **Relic** (e.g. corpses leave slowing ice, electric hits stun). Needs objective tracking + relic passive/event hooks.

### A6. Enemy debuffs (draft choice #3)
Temporary debuffs purchasable in the draft (weaker / slower / **downgrade a tier**). "Downgrade" implies an **ordered enemy progression** the data doesn't model yet — add that first.

### A7. Tower content beyond the starting set — IN PROGRESS
The "new tower" draft needs towers beyond the starting set to be meaningful. **Tesla Coil is the first** (Electric, AllInRange, ProBuilder mesh, draftable). The user planned **3 new towers** total so Siege + Wall can return to the starting deck — **2 more designs still pending** from the designer. Each new tower = a `TowerDefinition` + prefab + `NewTowerDraftOption`, added to `towerDefinitions` (catalog) + `DraftPool` (+ network prefab list).

### A8. Cross-match persistence / meta-progression
Player profile saving owned content; **win/loss reward pools** drawn server-side at match end; the customization menu. **Requires a session-stable tower/option ID** (catalog indices reset each match — see Context "technical debt").

### Open decisions (resolve as the relevant slice is scheduled)
- **Paint reconciliation:** keep paint as a separate axis, fold it into the systemic-upgrade visuals, or retire it. (Currently paused.)
- **Race vs Builder naming:** the code says "Race"; the design says "Builder." Rename, nest, or keep — decide before it calcifies.
- **Gold-roll availability:** currently any time; may tighten to prep-only.

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## Part B — Functional gameplay remainder (not roguelike-specific)

- **Tower Sell — ✅ DONE** (branch `tower-sell`): refund + despawn + coin VFX/SFX; 75% of invested gold, Wall 100% while un-upgraded, refund not counted as income; `TowerInstance.ServerAddUpgradeInvestment` records upgrade spend for the refund and is the seam the Upgrade system will write to.
- **Tower Upgrade action** — HUD button still disabled. Build it once the systemic-upgrade model (A3) settles whether per-tower upgrade trees are wanted on top of the systemic modifiers.
- **Enemy resistances / weaknesses** — `EnemyHealth.TakeDamage` has the stub slot; info panel has the placeholder.
- **Terrain architecture decision** — Unity Terrain vs mesh vs ProBuilder. Builder code is terrain-agnostic; decide before heavy art.
- **Camera polish** — cursor-anchored zoom near map edges, center-on-builder hotkey, race/phase-aware initial position.

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## Part C — Near-term art & visual TODOs

These are concrete, scheduled-soon visual fixes (placeholders are otherwise point-isolated and swap cleanly):

- **Grimdark lighting pass — NEXT.** The post-processing grade is in (ACES/desaturate/contrast/bloom/vignette, project-wide via `DefaultVolumeProfile`), but a brightly-lit ice map undercuts it. Lower the scene **ambient**, add a hard moody **directional key**, raise contrast — post can't carry grimdark without the lighting. (Ultimately the level art needs to go darker/industrial too.)
- **Enemy idle animation support.** Add idle states to **all** enemy prefabs (needed for held/spawned + between-waypoint states; foundation for the stepped-animation direction below).
- **Tower footprint visuals fill the full 2×2.** Meshes read smaller than the tile they occupy; make a placed tower visually fill its footprint (matters for maze readability, esp. the Wall).
- **Done this session:** per-tower **construction-phase build visuals** (`ConstructionPhaseSet`) and **ground-seating** so any-pivot meshes sit flush — both shipped.

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## Part D — Visual prototype: painted-miniature aesthetic (deferred phase)

Begins after the roguelike core is solid. Proves out the "photographed painted tabletop miniature" + Spider-Verse stepped-animation look on minimal content, as a concrete artifact for a future art lead. **Placeholder hero content (Space Marine + Hormagaunt-style) is GW-adjacent and private-only — see Part E.**

**Shared infrastructure (one-time, reused by all future assets):**
- **`MiniatureStandard` URP Shader Graph** — PBR + a **Fresnel rim** term (fakes drybrush edge highlights) and a **crushed-shadow** curve (studio-lit miniature look); optional low-intensity painted-noise overlay.
- **Lighting/post** via the volume profile — warm key (~45°), cool fill, low bounce, slightly raised AO, **tilt-shift DOF** (diorama scale), saturated warm-shadow grade, slight vignette.
- **`SteppedAnimator`** — samples the Animator pose and quantizes to ~12fps for **skeletal body + weapon-tracking only**; effects/projectiles/UI stay smooth (the contrast is what sells it). Builds on the enemy idle-animation work in Part C.
- **`TowerVisualController`** — local-only bridge from `TowerCombat` events (`OnTargetAcquired`/`OnTargetLost`/`OnFire`, `CurrentTarget`) to Animator params + procedural turret rotation.

**Prototype content:** one hero tower (idle/aim/fire) and one enemy (walk/death, stepped), then a **demo scene** showing towers shooting enemies in the painted-miniature look. Exit criteria: the demo runs in-editor with the aesthetic working end-to-end and the shared infra reusable.

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## Part E — Path to commercial production (notes only)

- **IP swap-out (required before any public release):** replace GW-adjacent placeholder content with original factions (the "armored warrior order" and "horde swarm" archetypes aren't owned; the specific GW execution is) — or pursue a GW license if the demo warrants. The data model already supports clean swap-out (asset-referenced definitions; code unaffected). The **asset manifest of IP-derived content must hit zero** before any public build, repo flip, or marketing.
- **Steam lobby migration (deferred):** replace Direct-IP with a Steam-backed provider behind an `IConnectionProvider` abstraction — **`NetworkBootstrap` is the single seam**; lobby UI and gameplay don't change. Adds friend-invite via overlay, lobby browser, Steam P2P transport; upgrades host-leave handling (Option A → lobby persists / new host). Use Spacewar app ID 480 in dev. Keep Direct-IP for LAN / DRM-free builds.
- **Production scope:** more towers/enemies/maps, audio direction matching the visual direction, art-lead hire (the Part D demo is the recruitment artifact).

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## Cross-phase principles

- **Debug to root cause** — no defensive workarounds or per-frame correction hacks.
- **Restate design intent before coding** — prevents rework; especially valuable for the roguelike systems and any art pipeline work.
- **Server-authoritative gameplay; local-only UI/visual state.**
- **Existing engine/rendering decisions stand:** Unity 6.4, URP, IL2CPP, .NET Standard 2.1, Linear color, new Input System, Force Text serialization, NGO 2.x.
