From: Lukas Krickl <lukas@krickl.dev>
Date: Fri, 14 Nov 2025 08:41:56 +0000 (+0100)
Subject: tiles: added test for food spread
X-Git-Url: https://git.krickl.dev/?a=commitdiff_plain;h=refs%2Fheads%2Fmaster;p=gbrg%2F.git

tiles: added test for food spread
---

diff --git a/src/tiles.s b/src/tiles.s
index 86c1d91..d61509f 100644
--- a/src/tiles.s
+++ b/src/tiles.s
@@ -243,17 +243,90 @@ tile_get_adjacent:
 
 	ret
 
+	; checks one tile for a type match
+	; inputs:
+	;		hl: ptr to next tile
+	;		 a: expected tile type
+	;		 b: current tile match count
+	;	returns:
+	;		incremnets b if type matches
+	;		hl+=2 (next ptr)
+	;	preserves:
+	;		a
+#macro tile_count_adjacent_check
+.beginscope
+		push af
+		ld a, [hl+]
+		ld d, a
+		ld a, [hl+]
+		ld e, a
+		; hl = next ptr
+
+		; de = ptr to tile
+		push hl
+		ld hl, t_type
+		add hl, de
+		; hl = tile type
+		ld a, [hl]
+		ld c, a ; c = tile type
+		pop hl
+
+		pop af
+		cp a, c
+		; check if match
+		jr nz, @no_match REL
+			inc b ; result++
+@no_match:
+.endscope
+#endmacro
+
+	; counts adjacent tiles of specific type
+	; inputs:
+	;		a: expected type
+	;	returns:
+	;		a: count of type
+tile_count_adjacent:
+	; b = result
+	ld b, 0
+
+	; hl = ptrs to tiles
+	ld hl, tiles_adjacent
+	
+	; check 8 tiles
+	tile_count_adjacent_check
+	tile_count_adjacent_check
+	tile_count_adjacent_check
+	tile_count_adjacent_check
+
+	tile_count_adjacent_check
+	tile_count_adjacent_check
+	tile_count_adjacent_check
+	tile_count_adjacent_check
+	
+	; result is in a now
+	ld a, b
+	ret
+
+
 	; updates empty tile
 	; inputs:
 	;		de: tile
 tile_update_empty:
+	ld a, TT_FOOD
+	push de
+	call tile_count_adjacent
+	pop de
+	
+	; if 2 adjacnet food tiles
+	; turn into food
+	cp a, 2 
+	ret c
 
-	; TODO: for now just inc t_tile
-	ld hl, t_tile
-	add hl, de
-	ld a, [hl]
-	inc a
-	; ld [hl], a
+	push de
+	pop hl ; hl = dst
+	ld de, tile_food
+	ld bc, t_size
+	call memcpy
 	ret
 	
 	; updates controlled tile