From 56ca39eb7ff87e7a9216c3c302566b2bf96a5264 Mon Sep 17 00:00:00 2001
From: Lukas Krickl <lukas@krickl.dev>
Date: Sat, 19 Oct 2024 05:13:20 +0200
Subject: [PATCH] Adding collision tile mask

---
 src/collision.s | 11 +++++++++++
 src/player.s    |  6 +++++-
 src/wram.s      |  1 +
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/collision.s b/src/collision.s
index 93192b8..c602dc5 100644
--- a/src/collision.s
+++ b/src/collision.s
@@ -37,6 +37,7 @@ collision_tile_lut:
   ; inputs:
   ;  hl: ptr to y/x position
   ;  de: collision point table 
+  ; ct_mask: bit mask for flag to check
   ; returns:
   ;   a = 0 -> no collision
   ;   a = 1 -> collision
@@ -96,6 +97,7 @@ collision_tile_table_check:
   ; inputs:
   ;     d : y pos 
   ;     e : x pos
+  ; ct_mask: bit mask for flag to check (tile & mask)
   ; returns:
   ;   a = 0 -> no collision
   ;   a = 1 -> collision
@@ -126,4 +128,13 @@ collision_tile:
   ld a, [hl] ; a = map flags row offset 
   add a, e ; row + x = position of tile in map 
 
+  ld d, 0
+  ld e, a ; de = tile offset 
+  ld hl, curr_room_flags ; hl = flags for currently loaded room 
+  add hl, de ; hl + de 
+  ld a, [hl] ; load flags
+  ld d, a
+  ld a, [ct_mask]
+  and a, d
+
   ret
diff --git a/src/player.s b/src/player.s
index 30eb25f..16205c9 100644
--- a/src/player.s
+++ b/src/player.s
@@ -49,7 +49,11 @@ player_init:
   ; inputs:
   ;   hl: pointer to player memory
 player_update:
-  ; update 
+  ; update
+
+  ; set collision mask
+  ld a, RF_WALL 
+  ld [ct_mask], a
 
   ; d: player_y
   ; e: player_x
diff --git a/src/wram.s b/src/wram.s
index 9e7e8de..755b57f 100644
--- a/src/wram.s
+++ b/src/wram.s
@@ -125,3 +125,4 @@ game_mode: .adv 1
   ; collision tile tmp values  
 ct_poy: .adv 1
 ct_pox: .adv 1
+ct_mask: .adv 1
-- 
2.30.2