From 568708afd3dc33cfac0ad5a453a3b08a4ce5e18f Mon Sep 17 00:00:00 2001
From: aerinon <randall.rupper@gmail.com>
Date: Mon, 10 Apr 2023 12:18:52 -0600
Subject: [PATCH] Fix Kholdstare shell collision at Lanmo 2 or other tiles
 where the shell could limit movement.

---
 .../bugfix/kholdstare_shell_collision.asm     | 51 +++++++++++++++++++
 doorrando/doorrando.asm                       |  1 +
 2 files changed, 52 insertions(+)
 create mode 100644 doorrando/bugfix/kholdstare_shell_collision.asm

diff --git a/doorrando/bugfix/kholdstare_shell_collision.asm b/doorrando/bugfix/kholdstare_shell_collision.asm
new file mode 100644
index 0000000..cfbf7a4
--- /dev/null
+++ b/doorrando/bugfix/kholdstare_shell_collision.asm
@@ -0,0 +1,51 @@
+pushpc
+
+org $9E9463
+JSL CheckKholdShellCoordinates
+BCC Sprite_A3_KholdstareShell_link_not_close
+BRA Sprite_A3_KholdstareShell_link_close
+NOP #13
+
+Sprite_A3_KholdstareShell_link_close = $9E9478
+Sprite_A3_KholdstareShell_link_not_close = $9E9480
+
+pullpc
+
+CheckKholdShellCoordinates:
+
+LDA.w $0D30, X
+XBA
+LDA.w $0D10, X  ; full 16 bit X coordinate of sprite
+
+REP #$21
+SBC.w #$0020
+CMP.b $22
+BCS .not_colliding
+
+ADC.w #$0040
+CMP.b $22
+BCC .not_colliding
+
+SEP #$20
+LDA.w $0D20, X
+XBA
+LDA.w $0D00, X  ; full 16 bit Y coordinate of sprite
+
+REP #$21
+SBC.w #$001F  ; could go to 27 and let link squeeze in at Lanmo 2 (please adjust the following one)
+CMP.b $20
+BCS .not_colliding
+
+ADC.w #$0037
+CMP.b $20
+BCC .not_colliding
+
+SEP #$20  ; collision detected
+SEC
+RTL
+
+.not_colliding
+SEP #$30
+CLC
+RTL
+
diff --git a/doorrando/doorrando.asm b/doorrando/doorrando.asm
index 6511dd2..08bdccd 100644
--- a/doorrando/doorrando.asm
+++ b/doorrando/doorrando.asm
@@ -58,6 +58,7 @@ incsrc math.asm
 incsrc hudadditions.asm
 incsrc dr_lobby.asm
 incsrc entrance_fixes.asm
+incsrc bugfix/kholdstare_shell_collision.asm
 warnpc $A79C00
 
 incsrc doortables.asm