File size: 19,498 Bytes

# Weapon System

Comprehensive reference for the Worms Armageddon 3.8.1 weapon system internals.

## Overview

The weapon system spans multiple subsystems: a **weapon table** defining all 71 weapons, an **ammo/delay tracker** per team/alliance, a **firing dispatch** that routes weapon activation to type-specific handlers, **CTaskMissile** objects for in-flight projectiles, and an **explosion system** for terrain damage.

### Object Relationships

```mermaid
graph TD
    DDGame["DDGame (0x98B8 bytes)"]
    WT["WeaponTable<br/>DDGame+0x510"]
    TAS["TeamArenaState<br/>DDGame+0x4628"]
    WP["WeaponPanel<br/>DDGame+0x548"]
    CTW["CTaskWorm<br/>(per-live-worm task)"]
    CTM["CTaskMissile<br/>(per-projectile task)"]
    EXP["CreateExplosion"]
    LAND["PCLandscape"]

    DDGame --> WT
    DDGame --> TAS
    DDGame --> WP
    CTW -->|"FireWeapon"| CTM
    CTW -->|"GetAmmo/SubtractAmmo"| TAS
    CTM -->|"impact"| EXP
    EXP -->|"terrain damage"| LAND
    WP -->|"reads availability"| WT
    WP -->|"reads ammo"| TAS
```

### Firing Sequence

```mermaid
sequenceDiagram
    participant P as Player Input
    participant W as CTaskWorm
    participant FR as WeaponRelease
    participant FW as FireWeapon
    participant CW as CreateWeaponProjectile
    participant M as CTaskMissile
    participant E as CreateExplosion
    participant L as PCLandscape

    P->>W: Fire key pressed
    W->>FR: WeaponRelease(0x51C3D0)<br/>position, angle
    FR->>FW: FireWeapon(0x51EE60)<br/>weapon type dispatch
    FW->>CW: CreateWeaponProjectile(0x51E0F0)
    CW->>M: CTaskMissile__Constructor(0x507D10)<br/>allocate 0x40C bytes
    loop Every frame
        M->>M: PhysicsUpdate(0x508C90)<br/>gravity, wind, collision
    end
    M->>E: CreateExplosion(0x548080)
    E->>L: ApplyExplosion(0x57C820)<br/>terrain bitmap damage
```

## WeaponEntry & WeaponTable

### WeaponTable (DDGame+0x510)

Allocated by `InitWeaponTable` (0x53CAB0, stdcall(wrapper), RET 0x4). Called once
during `CTaskGameState__vmethod_7` at game start.

```
+0x00   [WeaponEntry; 71]   entries     Standard weapons (0..70)
Total:  71 × 0x1D0 = 0x80B0 bytes (no header)
```

### WeaponEntry (0x1D0 = 464 bytes per entry)

Source: `wkJellyWorm/src/CustomWeapons.h` (WeaponStruct) + InitWeaponTable analysis.

```
+0x00   *const c_char   name1           Primary weapon name string
+0x04   *const c_char   name2           Secondary weapon name string
+0x08   i32             panel_state     Panel state (init: 0xFFFFFFFF). wkJellyWorm: panelRow
+0x0C   i32             unknown_0c      Unknown
+0x10   i32             defined         Nonzero = weapon exists. Checked by CheckWeaponAvail.
+0x14   [u8; 0x10]      unknown_14      Unknown
+0x24   i32             availability    Init: 0xFFFFFFFF, then 0 or 1. None/SkipGo/Surrender = 0.
+0x28   i32             enabled         Init: 1
+0x2C   [u8; 0x1A4]     unknown_2c      Remaining fields (opaque)
```

**InitWeaponTable per-entry initialization:**
- +0x08 = 0xFFFFFFFF (panel_state)
- +0x24 = 0xFFFFFFFF (availability, then overwritten per-weapon)
- +0x28 = 1 (enabled)
- Weapon 0 (None), 57 (SkipGo), 58 (Surrender): availability forced to 0

**Rust types:** `WeaponEntry`, `WeaponTable` in `openwa-core/src/game/weapon.rs`.

### Weapon Enum (71 entries)

Defined in `openwa-core/src/game/weapon.rs`. Key weapon IDs:

| ID | Hex | Name | Category |
|----|-----|------|----------|
| 0 | 0x00 | None | - |
| 1 | 0x01 | Bazooka | Projectile |
| 2 | 0x02 | HomingMissile | Projectile (homing) |
| 6 | 0x06 | Grenade | Thrown |
| 10 | 0x0A | Earthquake | Special (net-disabled) |
| 24 | 0x18 | SuperSheep | Animal (restricted) |
| 25 | 0x19 | AquaSheep | Animal (restricted) |
| 37 | 0x25 | NinjaRope | Rope |
| 40 | 0x28 | Teleport | Utility (immune to sudden death) |
| 54 | 0x36 | Donkey | Special (disable flag) |
| 55 | 0x37 | NuclearTest | Special (net-disabled) |
| 56 | 0x38 | Armageddon | Special (net-disabled) |
| 59 | 0x3B | SelectWorm | Action (needs >1 alive worm) |
| 66 | 0x42 | Invisibility | Power-up (mode flag) |
| 69 | 0x45 | DoubleTurnTime | Power-up (threshold) |

## Ammunition & Delay System

### Storage: TeamArenaState (DDGame+0x4628)

Ammo and delay are stored in a flat array indexed by alliance and weapon ID.

```
Flat index = alliance_id × 142 + weapon_id

Ammo:  TeamArenaState + 0x1EB4 + flat_index × 4
Delay: TeamArenaState + 0x1EB4 + (flat_index + 71) × 4

Values: -1 = unlimited, 0 = none, >0 = count
Delay:  0 = available, >0 = turns until available
```

6 alliances × 142 entries (71 ammo + 71 delay) = 852 total slots.

Alliance ID is read from the team's sentinel worm field at offset +0x80
(`sentinel_weapon_alliance`).

### Functions

| Function | Address | Convention | Parameters |
|----------|---------|------------|------------|
| GetAmmo | 0x5225E0 | usercall | EAX=team_index, ESI=arena_base, EDX=weapon_id → EAX=ammo |
| AddAmmo | 0x522640 | usercall | EAX=team_index, EDX=amount, stack(base, weapon_id), RET 0x8 |
| SubtractAmmo | 0x522680 | usercall | EAX=team_index, ECX=arena_base, stack(weapon_id), RET 0x4 |
| SubtractAmmo_v2 | 0x558E80 | fastcall | ECX=param1, EDX=CTaskTeam* |
| CountAliveWorms | 0x5225A0 | usercall | EAX=team_index, ECX=arena_base → EAX=count |

**GetAmmo special rules:**
- Returns 0 if weapon delay > 0 (weapon on cooldown)
- Sudden death (game_phase ≥ 484): returns 0 for all except Teleport (0x28)
- SelectWorm (0x3B): returns 0 if team has ≤1 alive worm
- Game mode flag at TeamArenaState+0x2C0C can override delay checks

**SubtractAmmo call sites (verified):**
- `CTaskWorm__HandleMessage` (0x512C27): subtracts Teleport (0x28) ammo
- `CTaskTeam_vt2__vmethod_2` (0x558443): subtracts the team's selected weapon
- `FUN_0055f8c0` (3 sites): subtracts DamageX2 (0x43), CrateSpy (0x44), and others

Our hook reportedly never triggered — this was because the test replay (bots)
doesn't use Teleport, DamageX2, or CrateSpy. The hook implementation is correct.

The second variant at 0x558E80 (fastcall) has 3 xrefs from `CTaskTeam_vt2__vmethod_2`.

**Port status:** All 4 functions ported in `replacements/weapon.rs`.

## Weapon Availability

### DDGame__CheckWeaponAvail (0x53FFC0)

Convention: fastcall(DDGame), ESI=weapon_id. Ported as `check_weapon_avail`
in `openwa-core/src/engine/game_state_init.rs`.

**Per-weapon disable rules:**

| Weapon(s) | Condition | Result |
|-----------|-----------|--------|
| Earthquake (10), NuclearTest (55), Armageddon (56) | `net_config_2 != 0 && net_weapon_exception == 0` | Disabled in network games |
| Donkey (54) | `donkey_disabled != 0` | GameInfo+0xD94C flag |
| Invisibility (66) | `invisibility_mode == 0 && network_ecx == 0` | Needs network or mode flag |
| DoubleTurnTime (69) | `game_version > 0xD1 && threshold > 0x7FFF` | GameInfo+0xD932 threshold |

**General availability path:**
1. Check weapon table entry: name1 non-null = weapon defined
2. If `level_width_raw == 0` OR weapon defined: check super weapon rules
3. `IsSuperWeapon` (0x565960): if super and `super_weapon_allowed == 0`, disable (unless game_version < 0x2A)
4. `supersheep_restricted` (DDGame+0x7E25): gates SuperSheep/AquaSheep check
5. `aquasheep_is_supersheep` (GameInfo+0xD956): when set, AquaSheep slot becomes SuperSheep

### DDGame__IsSuperWeapon (0x565960)

Convention: fastcall(weapon_id). Returns 1 for super weapons:

Super weapon IDs: 16, 19, 29-31, 36, 41-42, 45-46, 49-51, 54-56, 60-61

## FireWeapon Dispatch (0x51EE60)

Convention: thiscall. `in_EAX` = weapon context structure where:
- +0x30: weapon type (1-4)
- +0x34: subtype for type 3 and type 4
- +0x38: subtype for type 1 and type 2
- +0x3C: parameters base (passed to sub-functions)

`param_2` = DDGameWrapper pointer. Sets `param_2[0xF] = 1` on completion.

### Type 1: Projectile Weapons

| Subtype | Function | Address | Weapons |
|---------|----------|---------|---------|
| 1 | FireWeapon__PlacedExplosive | 0x51EC80 | Dynamite, Mine, Petrol Bomb |
| 2 | FireWeapon__Projectile | 0x51DFB0 | Bazooka, Mortar, Longbow |
| 3 | CreateWeaponProjectile | 0x51E0F0 | Homing Missile, Homing Pigeon |
| 4 | FireWeapon__Shotgun | 0x51ED90 | Shotgun, Handgun, Uzi, Minigun |

### Type 2: Rope Weapons

| Subtype | Function | Address | Weapons |
|---------|----------|---------|---------|
| 1 | FireWeapon__RopeType1 | 0x51E1C0 | Ninja Rope (attach) |
| 2 | CreateWeaponProjectile | 0x51E0F0 | Ninja Rope (projectile mode) |
| 3 | FireWeapon__RopeType3 | 0x51E240 | Bungee |

### Type 3: Thrown Weapons

| Subtype | Function | Address | Weapons |
|---------|----------|---------|---------|
| (all) | FireWeapon__GrenadeMortar | 0x51E2C0 | Grenade, Cluster Bomb, Banana Bomb, Holy Grenade |

### Type 4: Special Weapons

| Subtype | Function | Address | Description |
|---------|----------|---------|-------------|
| 1 | vtable[0xE](0x6C) | (indirect) | Blowtorch |
| 2 | FireWeapon__Special_Type2 | 0x51E3E0 | Pneumatic Drill |
| 3 | FireWeapon__Special_Type3 | 0x51E350 | Girder |
| 4 | vtable[0xE](0x6D) | (indirect) | Baseball Bat |
| 5 | vtable[0xE](0x75) | (indirect) | Fire Punch |
| 6 | vtable[0xE](0x70) | (indirect) | Dragon Ball |
| 8 | vtable[0xE](0x6E) | (indirect) | Kamikaze |
| 9 | FireWeapon__Special_Type9 | 0x51E480 | Prod |
| 10 | FireWeapon__Special_Type10 | 0x51E710 | Air Strike |
| 11 | vtable[0xE](0x71) | (indirect) | Scales of Justice |
| 13 | FireWeapon__Special_Type13 | 0x51E5C0 | Napalm Strike |
| 14 | FireWeapon__Special_Type14 | 0x51E670 | Mail/Mine/Mole Strike |
| 16 | FUN_0051EB00 (conditional) | 0x51EB00 | Teleport (checks FUN_516930 first) |
| 17 | FireWeapon__Special_Type17 | 0x51E920 | Freeze |
| 18 | vtable[0xE](0x72) | (indirect) | Suicide Bomber |
| 19 | FireWeapon__Special_Type19 | 0x51E8C0 | Skip Go |
| 20 | FireWeapon__Special_Type20 | 0x51E600 | Surrender |
| 21 | FireWeapon__Special_Type21 | 0x51EBE0 | Select Worm |
| 22 | FireWeapon__Special_Type22 | 0x51EC30 | Jet Pack |
| 23 | vtable[0xE](0x78) | (indirect) | Magic Bullet |
| 24 | FireWeapon__Special_Type24 | 0x51EA60 | Low Gravity / Fast Walk |

## CTaskMissile (0x40C bytes)

Extends CGameTask (0xFC base). Represents an in-flight projectile.

```
Constructor:  0x507D10 (stdcall, 4 params)
Vtable:       0x664438
Class type:   0x0B
Allocation:   0x40C bytes via wa_malloc
```

### Structure Layout

```
+0x000  CGameTask base          (0xFC bytes)
        +0x084  speed_x         Fixed16.16 horizontal velocity
        +0x088  speed_y         Fixed16.16 vertical velocity
        +0x090  pos_x           Fixed16.16 world X
        +0x094  pos_y           Fixed16.16 world Y

+0x128  u32     launch_seed     Position-derived seed
+0x12C  u32     slot_id         Object pool slot index

+0x130  spawn_params [11 DWORDs = 44 bytes]
        [0]     owner_id        Team that fired
        [2-3]   spawn_x/y       Fixed16.16 launch position
        [4-5]   speed_x/y       Fixed16.16 initial velocity
        [8]     pellet_index    Cluster volley index

+0x15C  weapon_data [94 DWORDs = 376 bytes]
        [0x0F]  gravity_pct     100 = 1.0× gravity
        [0x10]  bounce_pct      Bounce coefficient
        [0x12]  friction_pct    Friction coefficient
        [0x1A]  missile_type    2=Standard, 3=Homing, 4=Sheep, 5=Cluster
        [0x1C]  render_timer    Fuse countdown

+0x2D4  render_data [42 DWORDs = 168 bytes]
        Physics parameters (shifted copy of weapon_data)

+0x3C8  i32     direction       -1 (left) or +1 (right)
```

### Missile Type Enum

| Value | Type | Behavior |
|-------|------|----------|
| 2 | Standard | Straight trajectory with gravity |
| 3 | Homing | Tracks target position |
| 4 | Sheep | Walking behavior on terrain |
| 5 | Cluster | Splits into sub-munitions on impact |

### Key Methods

| Method | Address | Description |
|--------|---------|-------------|
| Constructor | 0x507D10 | Initialize physics, copy weapon data from scheme |
| Init | 0x508640 | Reset physics state |
| PhysicsUpdate | 0x508C90 | Per-frame trajectory, gravity, wind, collision |
| HandleMessage | 0x50B400 | Event processing (detonation triggers, etc.) |
| Free | 0x508330 | Cleanup and pool return |
| vt12 | 0x508C70 | Vtable slot 12 |
| vt18_GetField130 | 0x50BFA0 | Returns spawn_params pointer |

### Missile Count Limit

DDGame+0x72A4 tracks active missile count. `CreateWeaponProjectile` checks:
- If count + 7 < 0x2BD (701): create missile normally
- If exceeded and game_version < 0x3C: set error code 6 at DDGame+0x4624, load
  string resource 0x70F as error message at DDGame+0x7EF4
- Otherwise: silently fail

## Projectile Creation (0x51E0F0)

`CreateWeaponProjectile`: thiscall(this=context, param_2=missile_params, param_3=launch_params).

1. Read DDGame via `this+0x2C` (CTask.ddgame field)
2. Check missile count limit (DDGame+0x72A4 + 7 < 0x2BD)
3. Call `FUN_004FDF90(this)` — pool slot allocator
4. `wa_malloc(0x40C)` + `memset(0, 0x3EC)`
5. `CTaskMissile__Constructor(slot, missile_params, launch_params)`
6. Return allocated missile pointer

## Explosion & Terrain Damage

| Function | Address | Convention | Description |
|----------|---------|------------|-------------|
| CreateExplosion | 0x548080 | usercall(ESI=context) | Spawns explosion task via pool allocator + vtable dispatch |
| PCLandscape_ApplyExplosion | 0x57C820 | (unknown) | Modifies terrain bitmap, creates crater |

CreateExplosion is a thin wrapper: allocates via `FUN_004FDF90`, then calls
`vtable[2]()` on the allocated object. The actual explosion logic (radius,
damage, terrain removal) lives in the explosion task's ProcessFrame.

## Weapon Panel UI

| Function | Address | Description |
|----------|---------|-------------|
| DDGame__InitWeaponPanel_Maybe | 0x567770 | Initialize panel structures and availability grid |
| PrepareWeaponPanel | 0x568220 | Main panel renderer (~2000 lines). Iterates weapons by row, checks availability, renders tiles |
| WeaponPanelDrawTile | 0x567AA0 | Render individual weapon tile |
| WeaponPanelDescription | 0x567F80 | Show ammo/delay info on hover |
| WeaponPanelCheckClick | 0x5690B0 | Handle weapon selection clicks |

**Panel geometry:** 5 columns × 13 rows. Each tile is 29px wide.
Custom weapons (wkJellyWorm): dynamic columns up to 256 weapons.

## Weapon Crate System

- `CTaskCrate__Constructor` (0x502490): creates a weapon crate in the game world
- Crate probability per weapon defined in scheme (`WeaponSettings.crate_probability`, 0-100%)
- Crate drops award random weapons weighted by probability

## Scheme Integration

Weapon configuration flows from `.wsc` scheme files into GameInfo, then into the
weapon table and ammo arrays at game start.

### WeaponSettings (4 bytes per weapon)

```
+0x00   u8  ammo              0=none, 1-10=count, 0x80+=infinite
+0x01   u8  power             0-20 (max varies per weapon)
+0x02   u8  delay             Turn cooldown before available
+0x03   u8  crate_probability 0-100 percentage
```

### Scheme Formats

| Version | Payload | Weapons |
|---------|---------|---------|
| V1 | 0xD8 bytes | 45 standard weapons |
| V2 | 0x124 bytes | V1 + 19 super weapons |
| V3 | 0x192 bytes | V2 + 110 extended options (physics tweaks) |

**Port status:** Scheme parsing fully ported in `openwa-core/src/game/scheme.rs`
(10 hooks in `replacements/scheme.rs`).

## Complete Function Address Table

### Weapon Table & Initialization

| Function | Address | Convention | Port Status |
|----------|---------|------------|-------------|
| InitWeaponTable | 0x53CAB0 | stdcall(wrapper), RET 0x4 | Hooked (passthrough) |
| DDGame__CheckWeaponAvail | 0x53FFC0 | fastcall(DDGame) | **Ported** |
| DDGame__IsSuperWeapon | 0x565960 | fastcall(weapon_id) | **Ported** |
| DDGame__LoadHudAndWeaponSprites | 0x53D0E0 | stdcall(wrapper, ...) | Bridge call |

### Ammo System

| Function | Address | Convention | Port Status |
|----------|---------|------------|-------------|
| GetAmmo | 0x5225E0 | usercall(EAX,ESI,EDX) | **Ported** |
| AddAmmo | 0x522640 | usercall(EAX,EDX,stack), RET 0x8 | **Ported** |
| SubtractAmmo | 0x522680 | usercall(EAX,ECX,stack), RET 0x4 | **Ported** (may not trigger) |
| SubtractAmmo_v2 | 0x558E80 | fastcall(ECX,EDX) | Unported |
| CountAliveWorms | 0x5225A0 | usercall(EAX,ECX) | **Ported** |

### Firing & Projectiles

| Function | Address | Convention | Port Status |
|----------|---------|------------|-------------|
| WeaponRelease | 0x51C3D0 | thiscall(CTaskWorm*, ...) | Unported |
| FireWeapon | 0x51EE60 | thiscall, EAX=weapon_ctx | Unported |
| CreateWeaponProjectile | 0x51E0F0 | thiscall(context, params, launch) | Unported |
| CTaskMissile__Constructor | 0x507D10 | stdcall, 4 params | Unported |
| CTaskMissile__PhysicsUpdate | 0x508C90 | (unknown) | Unported |
| CTaskMissile__HandleMessage | 0x50B400 | thiscall | Unported |
| CreateExplosion | 0x548080 | usercall(ESI=context) | Unported |
| PCLandscape_ApplyExplosion | 0x57C820 | (unknown) | Unported |

### Fire Dispatch Targets

| Function | Address | Weapon Category |
|----------|---------|-----------------|
| FireWeapon__Projectile | 0x51DFB0 | Bazooka-class |
| FireWeapon__PlacedExplosive | 0x51EC80 | Dynamite/Mine/Petrol |
| FireWeapon__Shotgun | 0x51ED90 | Shotgun/Handgun/Uzi |
| FireWeapon__RopeType1 | 0x51E1C0 | Ninja Rope attach |
| FireWeapon__RopeType3 | 0x51E240 | Bungee |
| FireWeapon__GrenadeMortar | 0x51E2C0 | Grenade/Cluster/Banana |
| FireWeapon__Special_Type2 | 0x51E3E0 | Pneumatic Drill |
| FireWeapon__Special_Type3 | 0x51E350 | Girder |
| FireWeapon__Special_Type9 | 0x51E480 | Prod |
| FireWeapon__Special_Type10 | 0x51E710 | Air Strike |
| FireWeapon__Special_Type13 | 0x51E5C0 | Napalm Strike |
| FireWeapon__Special_Type14 | 0x51E670 | Mail/Mine/Mole Strike |

### Weapon Panel

| Function | Address | Convention | Port Status |
|----------|---------|------------|-------------|
| DDGame__InitWeaponPanel_Maybe | 0x567770 | thiscall | Unported |
| PrepareWeaponPanel | 0x568220 | cdecl | Unported |
| WeaponPanelDrawTile | 0x567AA0 | (unknown) | Unported |
| WeaponPanelDescription | 0x567F80 | (unknown) | Unported |
| WeaponPanelCheckClick | 0x5690B0 | (unknown) | Unported |

### Scheme

| Function | Address | Convention | Port Status |
|----------|---------|------------|-------------|
| Scheme__CheckWeaponLimits | 0x4D50E0 | stdcall | **Ported** |
| Scheme__ValidateExtendedOptions | 0x4D5110 | stdcall | **Ported** |
| Scheme__ReadFile | 0x4D3890 | stdcall | **Ported** |

## Port Recommendations

### Already Done
- Weapon enum and struct types (`WeaponEntry`, `WeaponTable`)
- Ammo system (4 hooks: GetAmmo, AddAmmo, SubtractAmmo, CountAliveWorms)
- Availability checks (2 hooks: CheckWeaponAvail, IsSuperWeapon)
- Scheme parsing (10 hooks covering all scheme I/O)
- Team/worm state queries (8 hooks in replacements/team.rs)

### Next Priority
1. **InitWeaponTable internals** — populate WeaponEntry fields from scheme data
2. **SubtractAmmo investigation** — verify hook triggers, check v2 variant
3. **Weapon panel init** — DDGame__InitWeaponPanel_Maybe (self-contained)

### Medium Term
4. **FireWeapon dispatch** — the type/subtype routing logic
5. **CreateWeaponProjectile** — missile allocation and pool management
6. **WeaponRelease** — coordinate transform and launch logic

### Long Term
7. **CTaskMissile physics** — gravity, wind, collision, homing AI
8. **Individual weapon behaviors** — each Fire__* handler
9. **Explosion system** — terrain damage, damage calculation
10. **Weapon panel rendering** — PrepareWeaponPanel (~2000 lines)