Projectile struct¶

This map documents projectile_pool (DAT_004926b8).

Notes:

• Entry size: 0x40 bytes.
• Pool size: 0x60 entries (loop in projectile_update).
• Primary writers: projectile_spawn (FUN_00420440) and projectile_update (FUN_00420b90).
• Field arrays are labeled in the data map (e.g. projectile_pos_x, projectile_type_id, projectile_life_timer, projectile_owner_id) at projectile_pool + offsets.

Struct view (projectile_t)¶

projectile_pool is typed as projectile_t (0x40 bytes).

typedef struct projectile_t {
    unsigned char active;
    unsigned char _pad0[3];
    float angle;
    float pos_x;
    float pos_y;
    float origin_x;
    float origin_y;
    float vel_x;
    float vel_y;
    int type_id;
    float life_timer;
    float reserved;
    float speed_scale;
    float damage_pool;
    float hit_radius;
    float base_damage;
    int owner_id;
} projectile_t;

Related tables:

• weapon_ammo_class (DAT_004d7a28) is consulted during projectile_update to gate one of the hit effect paths (value 4 skips it).

• weapon_projectile_damage_scale is used as the damage scale for each type_id.

• weapon_projectile_meta is copied into the projectile entry on spawn and shares the same stride as the weapon table.

• projectile_pool + 0x30 (DAT_004926e8) acts like a shared damage pool for piercing projectiles: it is decremented on hit and, if still positive, passed into creature_apply_damage (FUN_004207c0) as the damage value before subtracting the target's health.

Spawn notes:

• When Fire Bullets is active (player_fire_bullets_timer / DAT_00490bcc > 0 or player2_fire_bullets_timer / DAT_00490f2c > 0) and the owner is a player (owner_id == -100 / -1 / -2 / -3), projectile_spawn forces type_id to 0x2d regardless of the requested type.

Known type_id sources (partial, based on decompile in player_fire_weapon and bonus_apply):

Non-projectile weapon paths (player_update):

See Effects pools for secondary projectile type behaviors and particle style ids.

Rendering notes¶

projectile_render uses type_id to select atlas frames in artifacts/assets/crimson/game/projs.png. See Sprite atlas cutting for the current frame mapping table.

Some beam/chain effects override UVs with grim_set_uv_point to draw a thin strip from inside projs.png (see the atlas notes for the grid2 sub-cut). The overlays in Sprite atlas cutting show the exact UV slice.