Add implementation plan for Castle Ambush & Guard Capture System, including probe detection and capture mechanics

2025-10-03 16:49:36 -04:00
parent 5aba4e7311
commit 117dd70d2c
3 changed files with 1195 additions and 0 deletions
--- a/Sprites/Enemies/custom_guard.asm
+++ b/Sprites/Enemies/custom_guard.asm
@@ -0,0 +1,153 @@
+; This file contains the custom logic for the guard capture sequence.
+; WIP
+
+; 1. Place the new, expanded logic in a free bank ($1E).
+freedata bank $1E
+
+; This routine captures the player and warps them to a specific dungeon entrance.
+; It is a modified version of the WallMaster capture logic.
+; Expects the desired entrance ID to be in the A register.
+Oracle_CaptureAndWarp:
+{
+  STA.w $010E        ; Set the target entrance ID
+
+  LDA.b #$05         ; Game Mode 05: (hole/whirlpool transition)
+  STA.b $10          ; Set the game mode
+
+  STZ.b $2F          ; Clear Link's action state
+  STZ.b $5D          ; Clear Link's state (e.g., walking)
+
+  LDA.b #$02
+  STA.b $71          ; Set some kind of transition/camera flag
+
+  RTL
+}
+
+; This is a custom version of the Guard_Main routine from bank $05.
+; It is hooked to add the capture-and-warp logic.
+Hooked_Guard_Main:
+{
+  ; First, execute the two instructions that were overwritten by our JSL hook.
+  LDA.w $0DC0, X
+  PHA
+
+  ; --- Start of Ported Vanilla Code ---
+  LDY.w SprMiscC, X
+  PHY
+
+  LDA.w SprTimerB, X
+  BEQ .looking_around
+
+  LDA.w $05C234, Y ; SpriteDirections_Bank05, Y
+  STA.w SprMiscC, X
+
+  LDA.w $05C23A, Y ; SpriteDrawSteps_Bank05, Y
+  STA.w $0DC0, X
+
+.looking_around
+  JSR $05C4B8 ; Guard_HandleAllAnimation
+
+  PLA
+  STA.w SprMiscC, X
+
+  PLA
+  STA.w $0DC0, X
+
+  LDA.w $0DD0, X
+  CMP.b #$05
+  BNE .Guard_NotFalling
+
+  LDA.b $11
+  BNE .Return
+
+  JSR $05C4B5 ; Guard_TickTwiceAndUpdateBody
+  JMP $05C4B5 ; Guard_TickTwiceAndUpdateBody
+
+.Guard_NotFalling
+  JSR $05C1E1 ; Sprite_CheckIfActive_Bank05
+  JSL $05C55E ; Guard_ParrySwordAttacks
+
+  JSL $07E934 ; Sprite_CheckDamageToLink_long
+  BCS .hit_im
+
+  LDA.w $0FDC
+  BEQ .not_triggered
+
+.hit_im
+  ; --- MODIFICATION --- 
+  ; This is where the custom capture logic goes.
+  ; When a guard touches link, capture him and warp to the prison cell.
+  LDA.b #$F0 ; Placeholder Entrance ID for the prison cell.
+  JSL Oracle_CaptureAndWarp
+  RTL
+  ; --- END MODIFICATION ---
+
+.not_triggered
+  LDA.w $0EA0, X
+  BEQ .not_recoiling
+
+  CMP.b #$04
+  BCC .not_recoiling
+
+  LDA.b #$04
+  STA.w SprAction, X
+
+  LDA.b #$80
+
+.continue
+  JSR $05C4AF ; Guard_SetTimerAndAssertTileHitbox
+
+.not_recoiling
+  JSR $05C291 ; Sprite_CheckIfRecoiling_Bank05
+
+  LDA.w SprSubtype, X
+  AND.b #$07
+  CMP.b #$05
+  BCS .cant_go_over_short_tiles
+
+  LDA.w SprCollision, X
+  BNE .tile_collision
+
+  JSR $05C1D4 ; Sprite_Move_XY_Bank05
+
+.tile_collision
+  JSR $05C2A5 ; Sprite_CheckTileCollision_Bank05
+
+  BRA .continue_after_move
+
+.cant_go_over_short_tiles
+  JSR $05C1D4 ; Sprite_Move_XY_Bank05
+
+.continue_after_move
+  LDA.w SprAction, X
+  CMP.b #$04
+  BEQ .not_chasing
+
+  STZ.w $0ED0, X
+
+.not_chasing
+  REP #$30
+
+  AND.w #$00FF
+  ASL A
+  TAY
+
+  LDA.w $05C2C6, Y ; .vectors, Y
+  DEC A
+  PHA
+
+  SEP #$30
+
+.Return
+  RTS
+  ; --- End of Ported Vanilla Code ---
+}
+freedata clean
+
+; 2. Go to the vanilla code address and inject the jump.
+; The original instructions were LDA.w $0DC0,X (3 bytes) and PHA (1 byte).
+; A JSL is 4 bytes, so this is a perfect 1-to-1 replacement in size.
+pushpc
+org $05C227 ; Start of vanilla Guard_Main
+  JSL Hooked_Guard_Main
+pullpc