X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=ld45_start_nothing;a=blobdiff_plain;f=src%2Fgfx.asm;h=796ede04b4e17acde19f78b7bc879510a6080bc4;hp=a3f2d39ea2efc34d2c2d8f328bad797a814bb3d9;hb=2cef53ae69622dc995fa0f4ac7a6d793684b4403;hpb=6a16a1c526937ee551f968901cb949d55e35ecda

diff --git a/src/gfx.asm b/src/gfx.asm
index a3f2d39..796ede0 100644
--- a/src/gfx.asm
+++ b/src/gfx.asm
@@ -6,17 +6,19 @@
 ;    initializes the video hardware and graphics routines
 ; clear
 ;    clears the framebuffer (not vmem)
-;    clobbers: ax, cx, di
+;    clobbers: eax, ecx, edi
 ; swap_buffers
 ;    copies the framebuffer to video memory
-;    clobbers: ax, cx, di, si
+;    clobbers: eax, ecx, edi, esi
 ; wait_vsync
 ;    clobbers: al, dx
 ; set_palette_entry(idx[al], r[ah], g[bl], b[bh])
 ;    colors are 0-255
+	bits 32
+	section .text
 
-VIDMEM_SEG	equ 0a000h
-FRAMEBUF_SEG	equ 09000h
+VIDMEM_ADDR	equ 0a0000h
+FRAMEBUF_ADDR	equ 090000h
 
 REG_CRTC_STATUS	equ 3dah
 CRTC_VBLANK_BIT	equ 08h
@@ -24,53 +26,46 @@ CRTC_VBLANK_BIT	equ 08h
 REG_DAC_ADDR	equ 3c8h
 REG_DAC_DATA	equ 3c9h
 
+	extern sprsheet_cmap
+	extern sprsheet_tiles
+
+
+	global init_gfx
 init_gfx:
-	; video mode 13h (320x200 8bpp)
-	mov ax, 13h
-	int 10h
 	call clear
 
 	; setup the spritesheet palette
-	mov si, sprsheet_cmap
+	mov esi, sprsheet_cmap
 	xor cl, cl
 .cmaploop:
 	mov al, cl
-	mov ah, [si]
-	mov bl, [si + 1]
-	mov bh, [si + 2]
-	add si, 3
+	mov ah, [esi]
+	mov bl, [esi + 1]
+	mov bh, [esi + 2]
+	add esi, 3
 	call set_palette_entry
-	dec cl
+	inc cl
 	jnz .cmaploop
-	
 	ret
 
+
+	global clear
 clear:
-	push es
-	mov ax, FRAMEBUF_SEG
-	mov es, ax
-	xor di, di
-	xor ax, ax
-	mov cx, 16000
+	mov edi, FRAMEBUF_ADDR
+	xor eax, eax
+	mov ecx, 16000
 	rep stosd
-	pop es
 	ret
 
+	global swap_buffers
 swap_buffers:
-	push ds
-	push es
-	mov ax, FRAMEBUF_SEG
-	mov ds, ax
-	xor si, si
-	mov ax, VIDMEM_SEG
-	mov es, ax
-	xor di, di
-	mov cx, 16000
+	mov esi, FRAMEBUF_ADDR
+	mov edi, VIDMEM_ADDR
+	mov ecx, 16000
 	rep movsd
-	pop es
-	pop ds
 	ret
 
+	global wait_vsync
 wait_vsync:
 	mov dx, REG_CRTC_STATUS
 .wait_vblank_end:
@@ -100,50 +95,49 @@ set_palette_entry:
 	pop dx
 	ret
 
-	; slow_sprite(short id, short x, short y)
+	; slow_sprite(int id, int x, int y)
 	; assumptions: 32x32, one after the other, 0 is transparent
-	; XXX sprsheet needs to go to its own segment
+	global slow_sprite
 slow_sprite:
-	push bp
-	mov bp, sp
+	push ebp
+	mov ebp, esp
 	pusha
 
-	mov ax, FRAMEBUF_SEG
-	mov es, ax
-	mov ax, [bp + 8]	; ax <- y
-	sub ax, 16		; ax <- y - 16 (center sprite vertically)
-	mov bx, ax
-	shl ax, 8
-	shl bx, 6
-	add ax, bx		; ax <- (y - 16) * 320
-	mov di, [bp + 6]	; di <- x
-	sub di, 16		; di <- x - 16 (center sprite horizontally)
-	add di, ax		; di <- (y - 16) * 320 + (x - 16)
-
-	mov si, sprsheet_tiles
+	mov eax, [ebp + 16]	; ax <- y
+	sub eax, 16		; ax <- y - 16 (center sprite vertically)
+	mov ebx, eax
+	shl eax, 8
+	shl ebx, 6
+	add eax, ebx		; ax <- (y - 16) * 320
+	mov edi, [ebp + 12]	; di <- x
+	sub edi, 16		; di <- x - 16 (center sprite horizontally)
+	add edi, eax		; di <- (y - 16) * 320 + (x - 16)
+	add edi, FRAMEBUF_ADDR
+
+	mov esi, sprsheet_tiles
 	; calculate sprite id offset (each spr is 32*32=1k)
-	mov ax, [bp + 4]
-	shl ax, 10
-	add si, ax
+	mov eax, [ebp + 8]
+	shl eax, 10
+	add esi, eax
 
-	mov cx, 32
+	mov ecx, 32
 .yloop:
-	xor bx, bx
+	xor ebx, ebx
 .xloop:
-	mov al, [si]
+	mov al, [esi]
 	cmp al, 0
 	;jz .skip_pixel
-	mov [es:di + bx], al
+	mov [edi + ebx], al
 .skip_pixel:
-	inc si
-	inc bx
-	cmp bx, 32
+	inc esi
+	inc ebx
+	cmp ebx, 32
 	jnz .xloop
 
-	add di, 320
-	dec cx
+	add edi, 320
+	dec ecx
 	jnz .yloop
 
 	popa
-	pop bp
+	pop ebp
 	ret