Add support for loading 127x127 maps

scripts/generate_map.py

@@ -10,6 +10,7 @@ from PIL import Image
 GREEN = (0, 255, 0)
 RED = (255, 0, 0)
 BLUE = (0, 0, 255)
+YELLOW = (255, 255, 0)
 
 
 def abort(msg: str) -> NoReturn:
@@ -17,12 +18,12 @@ def abort(msg: str) -> NoReturn:
     sys.exit(1)
 
 
-SpawnPoint = Tuple[int, int]
+Point = Tuple[int, int]
 
 
 def generate_coll_map(
     in_path: pathlib.Path, width: int, height: int, compress: bool = False
-) -> Tuple[str, SpawnPoint]:
+) -> Tuple[str, Point, Point]:
     png = Image.open(in_path).convert("RGB")
     if png.width % 8 != 0 or png.height % 8 != 0:
         abort(f"file '{in_path}' has invalid dimensions (should be multiple of 8)")
@@ -33,6 +34,7 @@ def generate_coll_map(
     out_bytes = []
     bits = []
     spawn = None
+    camera = (0, 0)
 
     for y in range(png.height // 8):
         for x in range(png.width // 8):
@@ -46,6 +48,9 @@ def generate_coll_map(
             elif pixel == BLUE:
                 bit = 1
                 spawn = (x, y)
+            elif pixel == YELLOW:
+                bit = 1
+                camera = (x, y)
             else:
                 abort(f"unsupported pixel in collision map: {pixel}")
 
@@ -63,7 +68,7 @@ def generate_coll_map(
     if spawn is None:
         abort(f"no spawn point located")
 
-    return format_bytes(out_bytes, width=width), spawn
+    return format_bytes(out_bytes, width=width), spawn, camera
 
 
 def format_bytes(data: bytes, width: int = 16) -> str:
@@ -112,7 +117,9 @@ def generate_map(pngfile: str, compress: bool = False) -> None:
     section = pngpath.name.replace(".png", "")
 
     collpath = pngpath.parent / pngpath.name.replace(".png", "_coll.png")
-    coll_map, spawn = generate_coll_map(collpath, width, height, compress=compress)
+    coll_map, spawn, camera = generate_coll_map(
+        collpath, width, height, compress=compress
+    )
 
     with open(incpath, "w") as outf:
         outf.write(
@@ -134,10 +141,13 @@ ASSERT {section}_MAP_SIZE == {section}_WIDTH * {section}_HEIGHT
 {section}_TILE_PTR:   DW {section}_TILES
 {section}_TILE_SIZE:  DB ({section}_TILES_end - {section}_TILES)
 {section}_MAP_PTR:    DW {section}_MAP
+{section}_MAP_COLLISION: DW {section}_COLLISION
 {section}_MAP_WIDTH:  DB {width}
 {section}_MAP_HEIGHT: DB {height}
 {section}_SPAWN_X:    DB {spawn[0]}
 {section}_SPAWN_Y:    DB {spawn[1]}
+{section}_CAMERA_X:   DB {camera[0]}
+{section}_CAMERA_Y:   DB {camera[1]}
 
 {section}_MAP::
 {map_data}

src/bg.s

@@ -1,69 +0,0 @@
-INCLUDE "hardware.inc"
-INCLUDE "util.inc"
-
-INCLUDE "png/map/intro.inc"
-
-SECTION "BG Data", WRAM0
-
-BG_COLLISION_DATA:: dw
-BG_MAP_WIDTH:: db
-BG_MAP_HEIGHT:: db
-
-BG_SCROLLING:: db
-
-SECTION "BG Code", ROM0
-
-MACRO update_map_info
-    ld hl, BG_COLLISION_DATA
-    ld a, HIGH(\1)
-    ld [hl+], a
-    ld a, LOW(\1)
-    ld [hl+], a
-
-    ld a, \2
-    ld [hl+], a
-
-    ld a, \3
-    ld [hl+], a
-ENDM
-
-BG_Init::
-    SET8 BG_SCROLLING, 0
-
-    ; copy map
-    ld e, intro_HEIGHT
-    ld bc, _SCRN0
-    ld hl, intro_MAP
-.copy_map_row:
-    ld d, intro_WIDTH
-    call memcpy
-    dec e
-    jr z, .done
-    ; nothing to skip if map is max width
-    ld a, 32 - intro_WIDTH
-    or a
-    jr z, .copy_map_row
-    ld d, a
-.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, intro_TILES
-    ld bc, _VRAM
-    ld d, intro_NUM_TILES
-    call memcpy
-
-    update_map_info intro_COLLISION, intro_WIDTH, intro_HEIGHT
-
-    ret
-
-BG_Update::
-    ret

src/collision.s

@@ -103,16 +103,16 @@ can_move_to:
     push bc
     push hl
 
-    ld a, [BG_COLLISION_DATA]
+    ld a, [CURRENT_MAP_COLLISION]
     ld h, a
-    ld a, [BG_COLLISION_DATA + 1]
+    ld a, [CURRENT_MAP_COLLISION + 1]
     ld l, a
 
-    ld a, [BG_MAP_WIDTH]
+    ld a, [CURRENT_MAP_WIDTH]
     ld d, 0
     ld e, a
 
-    ; compute map index (HL + B * (BG_MAP_WIDTH + 1) + C)
+    ; compute map index (HL + B * (CURRENT_MAP_WIDTH + 1) + C)
 .mul_y_width:
     add hl, de
     dec b

src/main.s

@@ -29,10 +29,12 @@ start:
     ld hl, rIE
     ld [hl], IEF_VBLANK
 
-    call BG_Init
     call OAM_Init
-    call Keys_Init
-    call Player_Init
+    ; call Keys_Init
+    ; call Player_Init
+
+    ld hl, intro_Data
+    call Map_Load
 
     ; set palette
     ld a, %11100100
@@ -52,12 +54,12 @@ start:
     inc [hl]
 
     call Keys_Update
-    call Player_Update
-    call BG_Update
+    ; call Player_Update
 
     ; wait for vblank
     halt
 
+    ; ~160 cycles
     ld a, HIGH(_OAM)
     call DMA_Start
 

src/map.s

@@ -0,0 +1,262 @@
+INCLUDE "hardware.inc"
+INCLUDE "util.inc"
+
+SECTION "Map Data", WRAM0
+
+PAGEX:: DB
+PAGEY:: DB
+
+CURRENT_DATA_START::
+CURRENT_TILE_PTR:: DW
+CURRENT_TILE_SIZE:: DB
+CURRENT_MAP_PTR:: DW
+CURRENT_MAP_COLLISION:: DW
+CURRENT_MAP_WIDTH:: DB
+CURRENT_MAP_HEIGHT:: DB
+CURRENT_SPAWN_X:: DB
+CURRENT_SPAWN_Y:: DB
+CURRENT_CAMERA_X:: DB
+CURRENT_CAMERA_Y:: DB
+CURRENT_DATA_END::
+
+SECTION "Map Code", ROM0
+
+DEF INIT_SCX EQUS "((SCRN_VX - SCRN_X) / 2)"
+DEF INIT_SCY EQUS "((SCRN_VY - SCRN_Y) / 2)"
+
+DEF PAGE_SIZE EQU 2
+
+DEF STACK_OFFSET_ROW EQU 3
+DEF STACK_OFFSET_MAP EQU 1
+DEF STACK_OFFSET_LEFT EQU 0
+
+; TODO: Don't hardcode
+DEF CAMERAX EQU 0
+DEF CAMERAY EQU 14
+
+; Increments a 16-bit value located on the stack
+; \1 Stack offset
+MACRO INC_STACK16
+    ld hl, sp + \1
+    inc [hl]
+    jr nz, .no_carry\@
+
+    inc hl
+    inc [hl]
+
+.no_carry\@:
+ENDM
+
+MACRO ZERO_ROW_TILE
+    ld hl, sp + STACK_OFFSET_ROW
+    ld a, [hl+]
+    ld e, a
+    ld d, [hl]
+    xor a
+    ld [de], a
+ENDM
+
+; Loads a map
+; @param hl Pointer to map metadata
+Map_Load::
+    ; Initialize scroll state
+    ld a, INIT_SCX
+    ld [rSCX], a
+
+    ld a, INIT_SCY
+    ld [rSCY], a
+
+    xor a
+    ld [PAGEX], a
+    ld [PAGEY], a
+
+    ; Store metadata
+    ld bc, CURRENT_DATA_START
+    ld d, CURRENT_DATA_END - CURRENT_DATA_START
+    call memcpy
+
+    ; Write tiles to VRAM
+    ld hl, CURRENT_TILE_PTR
+    ld a, [hl+]
+    ld c, a
+    ld a, [hl+]
+    ld b, a
+
+    ld a, [CURRENT_TILE_SIZE]
+    ld d, a
+
+    ld hl, _VRAM
+    MEMCPY hl, bc, d
+
+    ; Write initial map data
+    ld hl, _SCRN0
+
+    ld a, [CURRENT_CAMERA_X]
+    sub INIT_SCX / 8
+    ld b, a
+
+    ld a, [CURRENT_CAMERA_Y]
+    sub INIT_SCY / 8
+    ld c, a
+
+    ld d, SCRN_VY_B
+.write_rows:
+    call write_map_row
+    inc c
+    dec d
+    jr nz, .write_rows
+
+    ret
+
+; Write a row of map data into map RAM
+; @param b Map X coordinate (signed)
+; @param c Map Y coordinate (signed)
+; @param hl Start of the row to write
+write_map_row:
+    push bc ; sp + 7
+    push de ; sp + 5
+    push hl ; sp + 3
+
+    ; If Y < 0, write a row of 0s
+    bit 7, c
+    jr nz, .zero_row
+
+    ; If Y >= MAP_HEIGHT, write a row of 0s
+    ld a, [CURRENT_MAP_HEIGHT]
+    dec a
+    cp c
+    jr nc, .begin_writing
+
+.zero_row:
+    ld d, SCRN_VX_B
+    xor a
+.zero_row_loop:
+    ld a, [hl+]
+    dec d
+    jr nz, .zero_row_loop
+.zero_row_done:
+    pop hl
+    pop de
+    pop bc
+    ret
+
+.begin_writing:
+    ; Allocate 2 bytes for map pointer
+    ; Allocate 1 byte for number of tiles left
+    add sp, -3
+
+    ; left = number of tiles left to write
+    ld hl, sp + STACK_OFFSET_LEFT
+    ld [hl], SCRN_VX_B
+
+    ; HL = CURRENT_MAP_PTR + Y * CURRENT_MAP_HEIGHT
+    ld a, [CURRENT_MAP_PTR]
+    ld l, a
+    ld a, [CURRENT_MAP_PTR + 1]
+    ld h, a
+
+.compute_map_row:
+    ld a, c
+    or a
+    jr z, .compute_map_row_done
+
+    ld a, [CURRENT_MAP_HEIGHT]
+    ADD16 HL
+    dec c
+    jr .compute_map_row
+
+    ; map = HL
+.compute_map_row_done:
+    LD16 de, hl
+    ld hl, sp + STACK_OFFSET_MAP
+    ld a, e
+    ld [hl+], a
+    ld a, d
+    ld [hl], a
+
+    ld hl, sp + STACK_OFFSET_LEFT
+
+    ; While X < 0 and left > 0, write 0 to the row
+.pad_left:
+    bit 7, b
+    jr z, .copy_center
+
+    ld a, [hl]
+    or a
+    jr z, .done
+
+    ; *row = 0
+    ZERO_ROW_TILE
+
+    ; row++
+    INC_STACK16 STACK_OFFSET_ROW
+
+    ; X++, left--
+    inc b
+    ld hl, sp + STACK_OFFSET_LEFT
+    dec [hl]
+    jr .pad_left
+
+    ; While X < MAP_WIDTH and [SP] > 0, copy from map
+.copy_center:
+    ld a, [CURRENT_MAP_WIDTH]
+    dec a
+    cp b
+    jr z, .pad_right
+
+    ld a, [hl]
+    or a
+    jr z, .done
+
+    ; A = *map_ptr
+    ld hl, sp + STACK_OFFSET_MAP
+    ld a, [hl+]
+    ld e, a
+    ld d, [hl]
+    ld a, [de]
+
+    ; map_ptr++
+    INC_STACK16 STACK_OFFSET_MAP
+
+    ; *row = A
+    ld hl, sp + STACK_OFFSET_ROW
+    ld e, [hl]
+    inc hl
+    ld d, [hl]
+    ld [de], a
+
+    ; row++
+    INC_STACK16 3
+
+    ; X++, [SP]--
+.copy_center_inc:
+    inc b
+    ld hl, sp + STACK_OFFSET_LEFT
+    dec [hl]
+    jr .copy_center
+
+    ; While [SP] > 0, write 0 to the row
+.pad_right:
+    ld a, [hl]
+    or a
+    jr z, .done
+
+    ; *row = 0
+    ZERO_ROW_TILE
+
+    ; row++
+    INC_STACK16 STACK_OFFSET_ROW
+
+    ; [SP]--
+.pad_right_inc:
+    ld hl, sp + STACK_OFFSET_ROW
+    dec [hl]
+    jr .pad_right
+
+.done:
+    add sp, 3
+    pop hl
+    pop de
+    pop bc
+
+    ret

src/player.s

@@ -38,15 +38,12 @@ Player_Init::
     inc hl
     ld [hl], 144-32
     inc hl
-    ld [hl], 0
-    inc hl
-    ld [hl], 0
-    inc hl
-    ld [hl], 0
-    inc hl
-    ld [hl], 0
-    inc hl
-    ld [hl], 0
+    xor a
+    ld [hl+], a
+    ld [hl+], a
+    ld [hl+], a
+    ld [hl+], a
+    ld [hl+], a
 
     ; Copy sprite to VRAM
     ld bc, _VRAM8000 + SPRITE_IDX * 16
@@ -55,39 +52,30 @@ Player_Init::
     call memcpy
 
     ; Initialize OAM entries with player state
-    call update_oam
+    call Player_UpdateOAM
 
     ret
 
 Player_Update::
-    ; suspend player state while map is scrolling
-    ld hl, BG_SCROLLING
-    ld a, [hl]
-    or a
-    ret nz
-
     ; check for jump
-    ld hl, keys
-    ld b, [hl]
-    ld a, b
+    ld a, [keys]
     and BTN_UP
     jr z, .jump_update_check
 
     ; initialize jump state if not already jumping
-    ld hl, PLAYER_JUMPING
-    ld a, [hl]
+    ld a, [PLAYER_JUMPING]
     or a
     jr nz, .jump_update
 
-    ld [hl], 1
+    ld a, 1
+    ld [PLAYER_JUMPING], a
 
     ld hl, PLAYER_VY
     STORE16 INIT_VY
 
 ; todo: deduplicate
 .jump_update_check:
-    ld hl, PLAYER_JUMPING
-    ld a, [hl]
+    ld a, [PLAYER_JUMPING]
     or a
     jr z, .right
 
@@ -120,7 +108,7 @@ Player_Update::
 
     ; roll back jump if there was a collision
     call player_bg_collides
-    jr z, .jump_update_oam
+    jr z, .jump_Player_UpdateOAM
 
 .jump_rollback:
     ld hl, PLAYER_VY
@@ -142,43 +130,44 @@ Player_Update::
     ld hl, PLAYER_VY
     bit 7, [hl]
 
-    ; either way, set VY = 0
+    ; either way, set VY = 0.
+    ; NOTE: MUST USE LD HERE TO KEEP FLAGS FROM BIT TEST
     ld [hl], 0
     ld hl, PLAYER_VY + 1
     ld [hl], 0
 
-    jr z, .jump_update_oam
+    jr z, .jump_Player_UpdateOAM
 
-    ld hl, PLAYER_JUMPING
-    ld [hl], 0
+    xor a
+    ld [PLAYER_JUMPING], a
 
-.jump_update_oam:
-    call update_oam
+.jump_Player_UpdateOAM:
+    call Player_UpdateOAM
 
     ; check for move right
 .right:
-    ld hl, keys
-    ld a, [hl]
+    ld a, [keys]
     and BTN_RIGHT
     jr z, .left
 
     ; check for right boundary
-    ld hl, PLAYER_X
-    ld a, [hl]
+    ld a, [PLAYER_X]
     add 16
     cp SCRN_X
     jr nc, .left
 
+.move_right:
+    ld hl, PLAYER_X
     inc [hl]
     inc [hl]
 
     call player_bg_collides
     jr nz, .right_rollback
 
-    ld hl, PLAYER_DIR
-    ld [hl], 0
+    xor a
+    ld [PLAYER_DIR], a
 
-    call update_oam
+    call Player_UpdateOAM
     ret
 
 .right_rollback:
@@ -195,21 +184,20 @@ Player_Update::
     jr z, .fall
 
     ; check for left boundary
-    ld hl, PLAYER_X
-    ld a, [hl]
+    ld a, [PLAYER_X]
     or a
     jr z, .fall
 
     sub PLAYER_SPEED
-    ld [hl], a
+    ld [PLAYER_X], a
 
     call player_bg_collides
     jr nz, .left_rollback
 
-    ld hl, PLAYER_DIR
-    ld [hl], $ff
+    ld a, $ff
+    ld [PLAYER_DIR], a
 
-    call update_oam
+    call Player_UpdateOAM
     jr .fall
 
 .left_rollback:
@@ -235,7 +223,7 @@ Player_Update::
     ret
 
 ; Update player metasprite with positional data
-update_oam:
+Player_UpdateOAM::
     ld hl, PLAYER_DIR
     ld a, [hl-] ; dir (0 = right , $ff = left)
     and OAMF_XFLIP