gbdk-2020 | GameBoy Development Kit |
| download: https://git.y1.nz/archives/gbdk.tar.gz | |
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commit bb791250e29f40150a8e9ba6eb6ae07b4cba1172 parent 221f1dd9e219ac72d7a0339630492be85c4a01ff Author: Phidias618 <126189685+Phidias618@users.noreply.github.com> Date: Mon, 18 May 2026 18:20:50 +0200 refactor CGB palette handling functions for the new calling convention for SM83 Diffstat:
| M | gbdk-lib/include/gb/cgb.h | 8 | ++++---- |
| M | gbdk-lib/libc/targets/sm83/cgb_compat.s | 19 | +++++++++++-------- |
| M | gbdk-lib/libc/targets/sm83/cgb_palettes.s | 124 | ++++++++++++++++++++++++++++++++++++++++++++----------------------------------- |
3 files changed, 84 insertions(+), 67 deletions(-)
diff --git a/gbdk-lib/include/gb/cgb.h b/gbdk-lib/include/gb/cgb.h @@ -101,7 +101,7 @@ typedef uint16_t palette_color_t; /**< 16 bit color entry */ @see BKGF_CGB_PAL0, BKGF_CGB_PAL1, BKGF_CGB_PAL2, BKGF_CGB_PAL3 @see BKGF_CGB_PAL4, BKGF_CGB_PAL5, BKGF_CGB_PAL6, BKGF_CGB_PAL7 */ -void set_bkg_palette(uint8_t first_palette, uint8_t nb_palettes, const palette_color_t *rgb_data) OLDCALL; +void set_bkg_palette(uint8_t first_palette, uint8_t nb_palettes, const palette_color_t *rgb_data) PRESERVES_REGS(b, c); /** Set CGB sprite palette(s). @@ -120,7 +120,7 @@ void set_bkg_palette(uint8_t first_palette, uint8_t nb_palettes, const palette_c @see OAMF_CGB_PAL0, OAMF_CGB_PAL1, OAMF_CGB_PAL2, OAMF_CGB_PAL3 @see OAMF_CGB_PAL4, OAMF_CGB_PAL5, OAMF_CGB_PAL6, OAMF_CGB_PAL7 */ -void set_sprite_palette(uint8_t first_palette, uint8_t nb_palettes, const palette_color_t *rgb_data) OLDCALL; +void set_sprite_palette(uint8_t first_palette, uint8_t nb_palettes, const palette_color_t *rgb_data) PRESERVES_REGS(b, c); /** Sets a single color in the specified CGB background palette. @@ -133,7 +133,7 @@ void set_sprite_palette(uint8_t first_palette, uint8_t nb_palettes, const palett @see BKGF_CGB_PAL4, BKGF_CGB_PAL5, BKGF_CGB_PAL6, BKGF_CGB_PAL7 */ -void set_bkg_palette_entry(uint8_t palette, uint8_t entry, uint16_t rgb_data) OLDCALL; +void set_bkg_palette_entry(uint8_t palette, uint8_t entry, uint16_t rgb_data) PRESERVES_REGS(b, c); /** Sets a single color in the specified CGB sprite palette. @@ -145,7 +145,7 @@ void set_bkg_palette_entry(uint8_t palette, uint8_t entry, uint16_t rgb_data) OL @see OAMF_CGB_PAL0, OAMF_CGB_PAL1, OAMF_CGB_PAL2, OAMF_CGB_PAL3 @see OAMF_CGB_PAL4, OAMF_CGB_PAL5, OAMF_CGB_PAL6, OAMF_CGB_PAL7 */ -void set_sprite_palette_entry(uint8_t palette, uint8_t entry, uint16_t rgb_data) OLDCALL; +void set_sprite_palette_entry(uint8_t palette, uint8_t entry, uint16_t rgb_data) PRESERVES_REGS(b, c); /** Set CPU speed to slow (Normal Speed) operation. diff --git a/gbdk-lib/libc/targets/sm83/cgb_compat.s b/gbdk-lib/libc/targets/sm83/cgb_compat.s @@ -9,13 +9,16 @@ _cgb_compatibility:: _set_default_palette:: - LD HL, #1$ - PUSH HL - LD HL, #0x0100 - PUSH HL - CALL _set_sprite_palette - CALL _set_bkg_palette - ADD SP, #4 - RET + ld bc, #1$ + xor a + ld e, #1 + push bc + call _set_sprite_palette ; preserve BC + + xor a + ld e, #1 + push bc + call _set_bkg_palette + ret 1$: .DW 0x7FFF, 0x56B5, 0x294A, 0x0000 diff --git a/gbdk-lib/libc/targets/sm83/cgb_palettes.s b/gbdk-lib/libc/targets/sm83/cgb_palettes.s @@ -5,74 +5,88 @@ .area _CODE +; void set_sprite_palette(uint8_t first_palette, uint8_t nb_palettes, const palette_color_t *rgb_data) PRESERVES_REGS(b, c); _set_sprite_palette:: ; Non-banked - PUSH BC - LD C,#.OCPS - JR .set_palette + ld d, c ; save C + ld c, #.OCPS + jr .set_palette +; void set_bkg_palette(uint8_t first_palette, uint8_t nb_palettes, const palette_color_t *rgb_data) PRESERVES_REGS(b, c); _set_bkg_palette:: ; Non-banked - PUSH BC - LD C,#.BCPS - + ld d, c ; save C + ld c, #.BCPS + + ; first_palette is in A + ; nb_palettes is in E + ; rgb_data is on the stack .set_palette:: - LDA HL,4(SP) ; Skip return address and registers - LD A,(HL+) ; first_palette - ADD A ; A *= 8 - ADD A - ADD A - OR #0x80 ; Set auto-increment - LDH (C),A - INC C - LD A,(HL+) ; D = nb_palettes - ADD A ; A *= 8 - ADD A - ADD A - LD B,A ; Number of bytes - LD A,(HL+) ; rgb_data - LD H,(HL) - LD L,A -1$: - WAIT_STAT + add a + add a + add a + or #0x80 ; Set auto-increment + ldh (c), a + inc c + + ; E = nb_palettes * 8 + ld a, e + add a + add a + add a + ld e, a - LD A,(HL+) - LDH (C),A - DEC B - JR NZ,1$ + ; hl = rgb_data + ldhl sp, #2 + ld a, (hl+) + ld h, (hl) + ld l, a +0$: + WAIT_STAT + + ld a, (hl+) + ldh (c), a + dec e + jr nz, 0$ - POP BC - RET + ld c, d ; restore C + pop hl ; get return address + pop af ; dummy pop + jp (hl) +; void set_sprite_palette_entry(uint8_t palette, uint8_t entry, uint16_t rgb_data) PRESERVES_REGS(b, c); _set_sprite_palette_entry:: ; Banked - PUSH BC - LD C,#.OCPS - JR .set_palette_entry + ld d, c ; save C + ld c, #.OCPS + jr .set_palette_entry +; void set_bkg_palette_entry(uint8_t palette, uint8_t entry, uint16_t rgb_data) PRESERVES_REGS(b, c); _set_bkg_palette_entry:: ; Banked - PUSH BC - LD C,#.BCPS + ld d, c ; save C + ld c, #.BCPS + ; palette is in A + ; entry is in E + ; rgb_data is on the stack .set_palette_entry:: - LDA HL,4(SP); Skip return address and registers - LD A,(HL+) ; first_palette - ADD A ; A *= 4 - ADD A - LD B,A - LD A,(HL+) ; pal_entry - ADD B ; A += first_palette * 4 - ADD A ; A *= 2 - OR #0x80 ; Set auto-increment - LDH (C),A - INC C + ; A = palette * 8 + entry * 2 + add a + add a + add e + add a + or #0x80 ; Set auto-increment + ldh (c), a + inc c + + ldhl sp, #2 LD A,(HL+) ; rgb_data - LD H,(HL) - LD L,A + LD E,(HL) - WAIT_STAT + WAIT_STAT_HL - LD A,L - LDH (C),A - LD A,H - LDH (C),A + ldh (c), a + ld a, e + ldh (c), a - POP BC - RET + ld c, d ; restore C + pop hl ; get return address + pop af ; dummy pop + jp (hl)
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