git.y1.nz

commit 252ca411850c487b1a210e83566588a11632f660
parent fa05104a5ee7b04415c0b49249501d59ce19e821
Author: Toxa <untoxa@mail.ru>
Date:   Wed, 12 May 2021 22:57:39 +0300

set_tile_data() allows to load tile data not taking into account LCDC bit 4 state

Diffstat:
M
gbdk-lib/include/gb/gb.h
11
+++++++++++
M
gbdk-lib/libc/gb/set_data.s
96
+++++++++++++++++++++++++++++++++++++++++--------------------------------------

2 files changed, 61 insertions(+), 46 deletions(-)
diff --git a/gbdk-lib/include/gb/gb.h b/gbdk-lib/include/gb/gb.h
@@ -1332,6 +1332,17 @@ void set_tiles(UINT8 x,
           unsigned char *vram_addr,
           const unsigned char *tiles) NONBANKED __preserves_regs(b, c);
 
+/** Sets VRAM Tile Pattern data starting from given base address
+
+    @param first_tile  Index of the first tile to write
+    @param nb_tiles    Number of tiles to write
+    @param data        Pointer to (2 bpp) source Tile Pattern data.
+	@param base        MSB of the destination address in VRAM (usually 0x80 or 0x90 which gives 0x8000 or 0x9000)
+*/
+void set_tile_data(UINT8 first_tile,
+          UINT8 nb_tiles,
+          const unsigned char *data,
+		  UINT8 base) NONBANKED __preserves_regs(b, c);
 
 /** Copies a rectangular region of Tile Map entries from a given VRAM Address into a buffer.
 
diff --git a/gbdk-lib/libc/gb/set_data.s b/gbdk-lib/libc/gb/set_data.s
@@ -1,55 +1,59 @@
-	.include	"global.s"
+        .include        "global.s"
 
-	;; BANKED:	checked
-	.area	_BASE
+        ;; BANKED:      checked
+        .area   _BASE
 
+_set_tile_data::
+        ldhl sp, #6
+        ld d,(hl)
+        jr .copy_tiles
 _set_bkg_data::
 _set_win_data::
-	ld d, #0x90
-	ldh a, (.LCDC)
-	bit 4, a
-	jr z, .copy_tiles
+        ld d, #0x90
+        ldh a, (.LCDC)
+        bit 4, a
+        jr z, .copy_tiles
 _set_sprite_data::
-	ld d, #0x80
+        ld d, #0x80
 .copy_tiles:
-	push bc
-	lda hl, 4(sp)
-	ld a, (hl+) ; ID of 1st tile
-	ld e, a
-	ld a, (hl+) ; Nb of tiles
-	ld c, a
-	ld a, (hl+) ; Src ptr
-	ld h, (hl)
-	ld l, a
-	
-	; Compute dest ptr
-	swap e ; *16 (size of a tile)
-	ld a, e
-	and #0x0F ; Get high bits
-	add d ; Add base offset of target tile "block"
-	ld d, a
-	ld a, e
-	and #0xF0 ; Get low bits only
-	ld e, a
+        push bc
+        ldhl sp, #4
+        ld a, (hl+) ; ID of 1st tile
+        ld e, a
+        ld a, (hl+) ; Nb of tiles
+        ld c, a
+        ld a, (hl+) ; Src ptr
+        ld h, (hl)
+        ld l, a
+        
+        ; Compute dest ptr
+        swap e ; *16 (size of a tile)
+        ld a, e
+        and #0x0F ; Get high bits
+        add d ; Add base offset of target tile "block"
+        ld d, a
+        ld a, e
+        and #0xF0 ; Get low bits only
+        ld e, a
 2$:
-	; Wrap from past $97FF to $8800 onwards
-	; This can be reduced to "bit 4 must be clear if bit 3 is set"
-	bit 3, d
-	jr z, 1$
-	res 4, d
+        ; Wrap from past $97FF to $8800 onwards
+        ; This can be reduced to "bit 4 must be clear if bit 3 is set"
+        bit 3, d
+        jr z, 1$
+        res 4, d
 1$:
-	ld b, #16
+        ld b, #16
 3$:
-	WAIT_STAT
-	ld a, (hl+)
-	ld (de), a
-	inc de
-	
-	dec b
-	jr nz, 3$
+        WAIT_STAT
+        ld a, (hl+)
+        ld (de), a
+        inc de
+        
+        dec b
+        jr nz, 3$
 
-	dec c
-	jr nz, 2$
-	
-	pop bc
-	ret
-
+        dec c
+        jr nz, 2$
+        
+        pop bc
+        ret
+

This webpage is intended to be an accessible preview of this repository. To get a fuller picture, clone it and use the git CLI.