From: Lukas Krickl <lukas@krickl.dev>
Date: Tue, 17 Feb 2026 06:59:57 +0000 (+0100)
Subject: mapgen: Room patterns are now randomly chosen.
X-Git-Url: https://git.krickl.dev/?a=commitdiff_plain;h=7d19337cc4649f142657405d3161d24bb92031af;p=gbrg%2F.git

mapgen: Room patterns are now randomly chosen.

Added init code for mapgen seed.
---

diff --git a/assets b/assets
index dfacc03..49200b3 160000
--- a/assets
+++ b/assets
@@ -1 +1 @@
-Subproject commit dfacc03a9d29342f17f2a688733c6124edc841a7
+Subproject commit 49200b3a091eca46b333f2d636e56f371d07fe52
diff --git a/makefile b/makefile
index 8c778e4..ba4d6d2 100644
--- a/makefile
+++ b/makefile
@@ -23,4 +23,5 @@ tiles:
 maps: 
 	./tools/tmx2map.py assets/maps/l1.tmx > maps/l1.inc
 	./tools/tmx2map.py assets/maps/f1r1.tmx > maps/f1r1.inc
+	./tools/tmx2map.py assets/maps/f1r2.tmx > maps/f1r2.inc
 
diff --git a/maps/f1r2.inc b/maps/f1r2.inc
new file mode 100644
index 0000000..9cdf1a0
--- /dev/null
+++ b/maps/f1r2.inc
@@ -0,0 +1,7 @@
+; this map was generated by tmx2map.py
+
+.db 0x1, 0x0, 0x0, 0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x1, 0x1, 0x1, 0x1, 0x1, 0x0, 0x0, 0x1, 0x1, 0x1
+.db 0x1, 0x1, 0x1, 0x0, 0x0, 0x1, 0x1, 0x1, 0x1, 0x1, 0x1, 0x0, 0x2, 0x1, 0x1, 0x1, 0x1, 0x1, 0x1, 0x2
+.db 0x0, 0x1, 0x1, 0x1, 0x1, 0x1, 0x1, 0x0, 0x0, 0x1, 0x1, 0x1, 0x1, 0x1, 0x1, 0x0, 0x0, 0x0, 0x0, 0x2
+.db 0x0, 0x0, 0x0, 0x0
+
diff --git a/src/mapgen.s b/src/mapgen.s
index fb7cfc1..b771602 100644
--- a/src/mapgen.s
+++ b/src/mapgen.s
@@ -10,7 +10,7 @@ map_generate:
 	ld bc, MAP_TILES
 	call memset
 	
-	; 1) setup seed
+	; 1) setup seed,,,
 	; store exiting seed in tmp game seed
 	ld a, [srand]
 	ld [mapgen_game_seed], a
@@ -164,6 +164,22 @@ mapgen_make_rooms:
 	;		hl: start position in tile map
 mapgen_make_room:
 	; TODO: pick a room pattern
+	push hl
+
+	ld b, a
+	call rand
+	dec b
+	and a, b ; ensure we are in range
+	add a, a ; *2 for offset
+
+	ld h, 0
+	ld l, a
+	add hl, de
+	push hl
+	pop de ; de = correct room to draw
+
+	pop hl
+
 	
 	; de = room pattern to draw
 	ld a, [de]
@@ -189,8 +205,11 @@ mapgen_make_room:
 
 f1r1:
 #include "f1r1.inc"
+f1r2:
+#include "f1r2.inc"
+
 
 floor1_patterns:
 dw f1r1
-dw f1r1
+dw f1r2
 floor1_patterns_end:
diff --git a/src/mem.s b/src/mem.s
index 21b9d2e..3249680 100644
--- a/src/mem.s
+++ b/src/mem.s
@@ -12,14 +12,15 @@ mem_init:
   ld bc, WRAMLEN/2
   call memset
 
+  ; set up rand
+  call rand_init
+
 	call map_globals_init
   
   ; set up shadow IE
   ld a, IVBLANK | ILCD
   ld [shadow_ie], a
 
-  ; set up rand
-  call rand_init
 
   ; copy shadow oam dma function 
   ld de, shadow_oam_to_oam 
diff --git a/src/rand.s b/src/rand.s
index 8414b11..e9b057c 100644
--- a/src/rand.s
+++ b/src/rand.s
@@ -12,6 +12,13 @@ rand_init:
   or a, 1
   ld [srand+1], a
 
+	ld a, [sram_mapgen_srand]
+	or a, 1
+	ld [mapgen_seed], a
+	ld a, [sram_mapgen_srand+1]
+	or a, 1
+	ld [mapgen_seed+1], a
+
   call mbc1_ram_disable
   ret
 
@@ -26,6 +33,12 @@ rand_save_srand:
   ld a, [srand+1]
   ld [sram_srand+1], a
 
+	; save mapgen seed in sram
+	ld a, [mapgen_seed]
+	ld [sram_mapgen_srand], a
+	ld a, [mapgen_seed+1]
+	ld [sram_mapgen_srand], a
+
   call mbc1_ram_disable
   ret
 
@@ -36,6 +49,8 @@ rand_save_srand:
   ;   a, hl, de
   ; returns:
   ;   a: random value
+	; uses:
+	;		hl, a
 rand:
   ; load seed
   ld a, [srand]
diff --git a/src/sram.s b/src/sram.s
index 27ee968..e6ffe55 100644
--- a/src/sram.s
+++ b/src/sram.s
@@ -10,3 +10,4 @@
   ; flag for init of sram
 sram_magic: .adv 1
 sram_srand: .adv 2
+sram_mapgen_srand: .adv 2