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oracle-of-secrets/Docs/Sprites/BusinessScrub.md
scawful 8c3bf9d95b Add documentation for custom enemy sprites: Eon Scrub, Keese, Leever, and Octorok
- Created detailed markdown files for Eon Scrub, Keese, Leever, and Octorok sprites.
- Included sprite properties, main logic, drawing routines, and design patterns for each sprite.
- Highlighted unique behaviors, state machines, and interactions with the player for each enemy type.
- Ensured clarity in the implementation details and provided assembly code snippets for reference.
2025-10-03 00:31:19 -04:00

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# Business Scrub
## Overview
The Business Scrub is a custom enemy sprite that likely overrides a vanilla sprite ID. It is characterized by its low health and harmless contact damage, suggesting its primary threat comes from projectiles or other interactions defined within its main logic.
## Sprite Properties
* **`!SPRID`**: `$00` (Vanilla sprite ID, likely overridden)
* **`!NbrTiles`**: `$02`
* **`!Health`**: `$01`
* **`!Damage`**: `$00` (Harmless contact)
* **`!Harmless`**: `$00`
* **`!Hitbox`**: `$08`
* **`!ImperviousAll`**: `$00`
* **`!Statue`**: `$00`
* **`!Prize`**: `$00`
* **`!Boss`**: `$00`
* **Collision Properties**: All collision-related properties (`!Defl`, `!SprColl`, etc.) are set to `$00`, indicating that direct contact damage and knockback are not handled by these properties. Interaction and damage are likely managed within the sprite's main logic.
## Main Structure (`Sprite_BusinessScrub_Long`)
This routine is the main entry point for the Business Scrub, executed every frame. It sets up bank registers, calls the drawing routine, and then executes the main logic if the sprite is active.
```asm
Sprite_BusinessScrub_Long:
{
PHB : PHK : PLB
JSR Sprite_BusinessScrub_Draw
JSL Sprite_DrawShadow
JSL Sprite_CheckActive : BCC .SpriteIsNotActive
JSR Sprite_BusinessScrub_Main
.SpriteIsNotActive
PLB
RTL
}
```
## Initialization (`Sprite_BusinessScrub_Prep`)
This routine runs once when the Business Scrub is spawned. It initializes the sprite's action state to `0` and sets a general-purpose timer (`SprTimerA`) to `120` frames (2 seconds).
```asm
Sprite_BusinessScrub_Prep:
{
PHB : PHK : PLB
%GotoAction(0)
%SetTimerA(120)
PLB
RTL
}
```
## Main Logic & State Machine (`Sprite_BusinessScrub_Main`)
The core behavior of the Business Scrub is managed by a state machine using `%SpriteJumpTable`. The current states are:
* **`State_Idle`**: The initial state where the scrub is idle. It plays an animation and checks for player proximity. If Link is within 80 pixels, it transitions to `State_Attacking`.
* **`State_Attacking`**: In this state, the scrub plays an attack animation, moves towards the player, and deals damage on contact. It also checks if it has been hit by the player and transitions to `State_Hurt` if so.
* **`State_Hurt`**: This state handles the sprite being hit, causing it to flash and be knocked back.
```asm
Sprite_BusinessScrub_Main:
{
%SpriteJumpTable(State_Idle, State_Attacking, State_Hurt)
State_Idle:
{
%PlayAnimation(0, 1, 15)
JSL GetDistance8bit_Long : CMP.b #$50 : BCS .player_is_far
%GotoAction(1)
.player_is_far
RTS
}
State_Attacking:
{
%PlayAnimation(2, 3, 8)
%MoveTowardPlayer(12)
%DoDamageToPlayerSameLayerOnContact()
JSL Sprite_CheckDamageFromPlayer : BCC .no_damage
%GotoAction(2)
.no_damage
RTS
}
State_Hurt:
{
JSL Sprite_DamageFlash_Long
RTS
}
}
```
## Drawing (`Sprite_BusinessScrub_Draw`)
The drawing routine uses the `%DrawSprite()` macro to render the sprite's graphics based on defined OAM data tables.
```asm
Sprite_BusinessScrub_Draw:
{
%DrawSprite()
.start_index
db $00, $02, $04, $06
.nbr_of_tiles
db 1, 1, 1, 1
.x_offsets
dw -8, 8, -8, 8, -8, 8, -8, 8
.y_offsets
dw -8, -8, -8, -8, -8, -8, -8, -8
.chr
db $C0, $C2, $C4, $C6, $C8, $CA, $CC, $CE
.properties
db $3B, $7B, $3B, $7B, $3B, $7B, $3B, $7B
}
```
## Design Patterns
* **State Machine**: Utilizes a clear state machine (`%SpriteJumpTable`) for managing different behaviors (Idle, Attacking, Hurt).
* **Player Interaction**: Incorporates distance checks (`GetDistance8bit_Long`) to trigger state changes and direct damage on contact (`DoDamageToPlayerSameLayerOnContact`).
* **Damage Handling**: Includes a basic damage reaction (`Sprite_CheckDamageFromPlayer`, `Sprite_DamageFlash_Long`).
* **Vanilla ID Override**: The use of `!SPRID = $00` suggests this sprite is intended to replace or modify the behavior of a vanilla sprite with ID $00.