From 75a7576e1752c43ed6963de48d0cc022f125ef59 Mon Sep 17 00:00:00 2001
From: Forest Belton <65484+forestbelton@users.noreply.github.com>
Date: Mon, 28 Jun 2021 23:45:37 -0400
Subject: [PATCH] Draw background

---
 src/bg.s     | 120 +++++++++++++++++++++++++++++++++++++++++++++++++++
 src/main.s   |  30 ++++---------
 src/player.s |   7 ++-
 src/util.s   |   2 +-
 4 files changed, 134 insertions(+), 25 deletions(-)
 create mode 100644 src/bg.s

diff --git a/src/bg.s b/src/bg.s
new file mode 100644
index 0000000..c27de18
--- /dev/null
+++ b/src/bg.s
@@ -0,0 +1,120 @@
+INCLUDE "hardware.inc"
+
+; SCENE.Z80
+;
+; Map Source File.
+;
+; Info:
+;   Section       : ROM0
+;   Bank          : 0
+;   Map size      : 20 x 18
+;   Tile set      : C:\Users\case\Downloads\woods.gbr
+;   Plane count   : 1 plane (8 bits)
+;   Plane order   : Tiles are continues
+;   Tile offset   : 0
+;   Split data    : No
+;
+; This file was generated by GBMB v1.8
+
+sceneWidth  EQU 20
+sceneHeight EQU 18
+
+SECTION "BG0", ROM0
+
+bg:
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $01,$02,$02,$03,$00,$00,$00,$00,$01,$02
+DB $02,$02,$02,$02,$02,$0A,$03,$00,$00,$00
+DB $07,$09,$09,$08,$00,$00,$00,$00,$07,$09
+DB $09,$09,$09,$09,$09,$0B,$08,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$0C,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$0A,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$0B,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$0C,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$0A,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$01,$02,$02,$02,$02,$02
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$07,$09,$09,$09,$09,$09
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$01,$02,$02,$02
+DB $02,$02,$03,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$07,$09,$09,$09
+DB $09,$09,$08,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00
+DB $01,$02,$02,$02,$02,$02,$02,$02,$02,$02
+DB $02,$02,$02,$02,$02,$02,$02,$02,$02,$02
+DB $04,$06,$06,$06,$06,$06,$06,$06,$06,$06
+DB $06,$06,$06,$06,$06,$06,$06,$06,$06,$06
+bg_end:
+
+bg_tiles:
+    DB $00,$00,$00,$00,$00,$00,$00,$00
+    DB $00,$00,$00,$00,$00,$00,$00,$00
+    DB $FF,$FF,$DF,$80,$FD,$80,$77,$40
+    DB $3F,$3F,$22,$3D,$20,$3F,$28,$37
+    DB $FF,$FF,$DF,$00,$FD,$00,$F7,$00
+    DB $FF,$FF,$40,$BF,$01,$FE,$10,$EF
+    DB $FF,$FF,$FB,$01,$BF,$01,$EE,$02
+    DB $FC,$FC,$44,$BC,$04,$FC,$14,$EC
+    DB $22,$3D,$30,$2F,$24,$3B,$20,$3F
+    DB $20,$3F,$32,$2D,$20,$3F,$28,$37
+    DB $44,$BC,$0C,$F4,$24,$DC,$04,$FC
+    DB $04,$FC,$4C,$B4,$04,$FC,$14,$EC
+    DB $40,$BF,$02,$FD,$20,$DF,$00,$FF
+    DB $08,$F7,$40,$BF,$02,$FD,$10,$EF
+    DB $20,$3F,$22,$3D,$10,$1F,$0F,$0F
+    DB $00,$00,$00,$00,$00,$00,$00,$00
+    DB $04,$FC,$44,$BC,$08,$F8,$F0,$F0
+    DB $00,$00,$00,$00,$00,$00,$00,$00
+    DB $40,$BF,$02,$FD,$20,$DF,$FF,$FF
+    DB $00,$00,$00,$00,$00,$00,$00,$00
+    DB $FF,$FF,$FF,$81,$FF,$81,$FF,$81
+    DB $FF,$FF,$FF,$FF,$FF,$FF,$FF,$81
+    DB $FF,$81,$FF,$81,$FF,$FF,$FF,$FF
+    DB $FF,$FF,$FF,$81,$FF,$81,$FF,$81
+    DB $FF,$FF,$FF,$FF,$FF,$FF,$FF,$81
+    DB $FF,$81,$FF,$81,$FF,$FF,$FF,$FF
+bg_tiles_end:
+
+BG_Init::
+    ; copy map
+    ld e, 18
+    ld bc, _SCRN0
+    ld hl, bg
+.copy_map_row:
+    ld d, 20
+    call memcpy
+    dec e
+    jr z, .done
+    ld d, 32 - 20
+.skip:
+    ; skip over trailing part in vram
+    inc c
+    jr nz, .nocarry
+    inc b
+.nocarry:
+    dec d
+    jr nz, .skip
+    jr .copy_map_row
+.done:
+
+    ; copy tiles
+    ld hl, bg_tiles
+    ld bc, _VRAM
+    ld d, bg_tiles_end - bg_tiles
+    call memcpy
+
+    ret
diff --git a/src/main.s b/src/main.s
index a4cc98b..a13045e 100644
--- a/src/main.s
+++ b/src/main.s
@@ -21,38 +21,24 @@ start:
     res 7, [hl]
     res 2, [hl]
 
-    ; set tilemap to tile index 1
-    ld hl, _SCRN0
-    ld a, 1
-    ld c, 32
-.loop0:
-    ld b, 32
-.loop1
-    ld [hli], a
-    dec b
-    jr nz, .loop1
-    dec c
-    jr nz, .loop0
-
-    ; clear 2nd sprite
-    ld hl, _VRAM + 16
-    ld a, 0
-    ld c, 16
-    call memset
-
+    call BG_Init
     call OAM_Init
     call Keys_Init
     call Player_Init
 
+    ; set palette
+    ld a, %11100100
+    ld hl, rOBP0
+    ld [hl], a
+    ld hl, rBGP
+    ld [hl], a
+
     ; enable lcd, sprites and interrupts
     ld hl, rLCDC
     set 7, [hl]
     set 1, [hl]
     ei
 
-    ld hl, rOBP0
-    ld [hl], %11100100
-
 .loop:
     ld hl, frame
     inc [hl]
diff --git a/src/player.s b/src/player.s
index c8ec48a..56a3bb6 100644
--- a/src/player.s
+++ b/src/player.s
@@ -11,12 +11,14 @@ Section "Player Code", ROM0
 spriteData:
     INCBIN "png/player.2bpp"
 
+DEF SPRITE_IDX EQU 32
+
 Player_Init::
     ld a, 8
     ld hl, _OAM + 1
     ld [hl], a
 
-    ld bc, _VRAM8000
+    ld bc, _VRAM8000 + SPRITE_IDX * 16
     ld hl, spriteData
     ld d, 16
     call memcpy
@@ -26,8 +28,9 @@ Player_Init::
     ld [hli], a
     ld a, 8
     ld [hli], a
-    xor a
+    ld a, SPRITE_IDX
     ld [hli], a
+    xor a
     ld [hli], a
 
     ld bc, _OAMRAM
diff --git a/src/util.s b/src/util.s
index 24614c0..07705a2 100644
--- a/src/util.s
+++ b/src/util.s
@@ -9,9 +9,9 @@ waitForVblank::
     ret
 
 ; Copies data between two regions
-; @param d  Size (in bytes) to copy. Must be >0
 ; @param bc Pointer to the destination region
 ; @param hl Pointer to the source region
+; @param d  Size (in bytes) to copy. Must be >0
 memcpy::
     ld a, [hli]
     ld [bc], a