c4.asm

SFC游戏模拟器 snes9x 1.43 的原代码

    mov cl,[esi+1F89h]
    mov ch,[esi+1F8Ch]
    mov [C4SprPos+2],cx
    movsx eax,word[esi+1F86h]
    mov [.scalex],eax
    movsx eax,word[esi+1F8Fh]
    mov [.scaley],eax
    mov esi,[C4SprPtr]
    mov edi,[C4Ram]
    add edi,2000h

    ; convert to 8-bit bitmap
    mov cx,[C4SprPos+2]
    shr cl,1
.loop2
    mov al,[esi]
    mov [edi],al
    mov al,[esi]
    shr al,4
    mov [edi+1],al
    inc esi
    add edi,2
    dec cl
    jnz .loop2
    dec ch
    jnz .loop2

    mov edi,[C4Ram]
    add edi,4000h
    mov ecx,2000h
.lp
    mov byte[edi],0
    inc edi
    loop .lp

    mov esi,[C4Ram]
    add esi,2000h
    mov edi,[C4Ram]
    add edi,4000h

    mov cx,[C4SprPos+2]
.next2
    push ebx
.next
    xor eax,eax
    mov ah,[C4SprPos+2]
    cmp ebx,eax
    jae .fail
    xor eax,eax
    mov ah,[C4SprPos+3]
    cmp edx,eax
    jae .fail
    push ecx
    push edx
    xor eax,eax
    mov al,[C4SprPos+2]
    xor ecx,ecx
    mov cl,dh
    mul ecx
    mov ecx,ebx
    shr ecx,8
    add eax,ecx
    mov dl,[esi]
    cmp eax,2000h
    jae .skipdisi
    mov [edi+eax],dl
.skipdisi
    pop edx
    pop ecx
.fail
    inc esi
    add ebx,[.scalex]
    dec cl
    jnz near .next
    pop ebx
    add edx,[.scaley]
    mov cl,[C4SprPos+2]
    dec ch
    jnz near .next2

.skipall
    ; convert to 4-bit bitmap
    mov esi,[C4Ram]
    add esi,4000h
    mov edi,[C4Ram]
    add edi,6000h
    mov cx,[C4SprPos+2]
    shr cl,1
.loop
    mov al,[esi]
    mov [edi],al
    mov al,[esi+1]
    shl al,4
    or [edi],al
    inc edi
    add esi,2
    dec cl
    jnz .loop
    dec ch
    jnz .loop

    mov esi,[C4Ram]
    add esi,6000h
;    mov esi,[C4SprPtr]
    mov eax,[C4Ram]
    xor ebx,ebx
    mov bl,[C4SprPos]
    call C4SprBitPlane

    popad
    ret

SECTION .data
.scalex dd 0
.scaley dd 0
SECTION .text

C4BitPlaneWave:
    pushad
    mov esi,[C4Ram]
    mov dword[.temp],10h
    xor eax,eax
    mov al,[esi+1F83h]
    mov dword[.waveptr],eax
    mov word[.temp+4],0C0C0h
    mov word[.temp+6],03F3Fh
.bmloopb
    mov edi,[C4Ram]
    add edi,[.waveptr]
    xor eax,eax
    movsx ax,byte[edi+$0B00]
    neg ax
    sub ax,16
    mov edi,[C4Ram]
    add edi,0A00h
    xor ecx,ecx
.bmloopa
    mov ebx,[.bmptr+ecx*4]
    mov dx,[.temp+6]
    and [esi+ebx],dx
    xor dx,dx
    cmp ax,0
    jl .less
    mov dx,0FF00h
    cmp ax,8
    jae .less
    mov dx,[edi+eax*2]
.less
    and dx,[.temp+4]
    or [esi+ebx],dx
    inc ax
    inc ecx
    cmp ecx,28h
    jne .bmloopa
    add dword[.waveptr],1
    and dword[.waveptr],07Fh
    ror word[.temp+4],2
    ror word[.temp+6],2
    cmp word[.temp+4],0C0C0h
    jne near .bmloopb
    add esi,16
.bmloopa2b
    mov edi,[C4Ram]
    add edi,[.waveptr]
    xor eax,eax
    movsx ax,byte[edi+$0B00]
    neg ax
    sub ax,16
    mov edi,[C4Ram]
    add edi,0A00h
    xor ecx,ecx
.bmloopa2
    mov ebx,[.bmptr+ecx*4]
    mov dx,[.temp+6]
    and [esi+ebx],dx
    xor dx,dx
    cmp ax,0
    jl .less2
    mov dx,0FF00h
    cmp ax,8
    jae .less2
    mov dx,[edi+eax*2+16]
.less2
    and dx,[.temp+4]
    or [esi+ebx],dx
    inc ax
    inc ecx
    cmp ecx,28h
    jne .bmloopa2
    add dword[.waveptr],1
    and dword[.waveptr],07Fh
    ror word[.temp+4],2
    ror word[.temp+6],2
    cmp word[.temp+4],0C0C0h
    jne near .bmloopa2b
    add esi,16
    dec dword[.temp]
    jnz near .bmloopb
    mov esi,[C4Ram]
;    mov cx,[esi+1F80h]
;    mov [C4values],cx
;    mov cx,[esi+1F83h]
;    mov [C4values+2],cx
    popad
    ret

SECTION .data
.bmptr dd 0000h,0002h,0004h,0006h,0008h,000Ah,000Ch,000Eh
       dd 0200h,0202h,0204h,0206h,0208h,020Ah,020Ch,020Eh
       dd 0400h,0402h,0404h,0406h,0408h,040Ah,040Ch,040Eh
       dd 0600h,0602h,0604h,0606h,0608h,060Ah,060Ch,060Eh
       dd 0800h,0802h,0804h,0806h,0808h,080Ah,080Ch,080Eh
.temp dd 0,0
.waveptr dd 0
;C4X1 dw 0
;C4Y1 dw 0
;C4Z1 dw 0
;C4X2 dw 0
;C4Y2 dw 0
;C4Z2 dw 0
;C4Col dw 0

SECTION .text
C4DrawLine:
    pushad

    ; transform both coordinates
    push esi
    mov ax,word[C4X1]
    mov [C4WFXVal],ax
    mov ax,word[C4Y1]
    mov [C4WFYVal],ax
    mov ax,word[C4Z1]
    mov [C4WFZVal],ax
    mov al,[esi+1F90h]
    mov [C4WFScale],al
    mov al,[esi+1F86h]
    mov [C4WFX2Val],al
    mov al,[esi+1F87h]
    mov [C4WFY2Val],al
    mov al,[esi+1F88h]
    mov [C4WFDist],al
EXTSYM C4TransfWireFrame2
    call C4TransfWireFrame2
    mov ax,[C4WFXVal]
    mov word[C4X1],ax
    mov ax,[C4WFYVal]
    mov word[C4Y1],ax

    mov ax,word[C4X2]
    mov [C4WFXVal],ax
    mov ax,word[C4Y2]
    mov [C4WFYVal],ax
    mov ax,word[C4Z2]
    mov [C4WFZVal],ax
    call C4TransfWireFrame2
    mov ax,[C4WFXVal]
    mov word[C4X2],ax
    mov ax,[C4WFYVal]
    mov word[C4Y2],ax

    add word[C4X1],48
    add word[C4Y1],48
    add word[C4X2],48
    add word[C4Y2],48
    shl dword[C4X1],8
    shl dword[C4X2],8
    shl dword[C4Y1],8
    shl dword[C4Y2],8
    ; get line info
    mov ax,[C4X1+1]
    mov [C4WFXVal],ax
    mov ax,[C4Y1+1]
    mov [C4WFYVal],ax
    mov ax,[C4X2+1]
    mov [C4WFX2Val],ax
    mov ax,[C4Y2+1]
    mov [C4WFY2Val],ax
    call C4CalcWireFrame
    xor ecx,ecx
    mov cx,[C4WFDist]
    or ecx,ecx
    jnz .not0
    mov ecx,1
.not0
    movsx eax,word[C4WFXVal]
    mov [C4X2],eax
    movsx eax,word[C4WFYVal]
    mov [C4Y2],eax
    pop esi
    ; render line
.loop
    ; plot pixel
    cmp word[C4X1+1],0
    jl near .noplot
    cmp word[C4Y1+1],0
    jl near .noplot
    cmp word[C4X1+1],95
    jg near .noplot
    cmp word[C4Y1+1],95
    jg near .noplot
    xor eax,eax
    mov dx,[C4Y1+1]
    shr dx,3
    mov ax,dx
    shl ax,6
    shl dx,8
    sub dx,ax
    mov ax,[C4X1+1]
    shr ax,3
    shl ax,4
    add ax,dx
    mov dx,[C4Y1+1]
    and dx,07h
    add dx,dx
    add ax,dx
    mov dl,07Fh
    push ecx
    mov cl,[C4X1+1]
    and cl,07h
    ror dl,cl
    pop ecx
    and byte[esi+eax+300h],dl
    and byte[esi+eax+301h],dl
    xor dl,0FFh
    test byte[C4Col],1
    jz .nocolor0
    or byte[esi+eax+300h],dl
.nocolor0
    test byte[C4Col],2
    jz .nocolor1
    or byte[esi+eax+301h],dl
.nocolor1
.noplot
    mov eax,[C4X2]
    add [C4X1],eax
    mov eax,[C4Y2]
    add [C4Y1],eax
    dec ecx
    jnz near .loop
    popad
    ret

DrawWireFrame:
    mov esi,[C4Ram]
    mov edi,esi
    xor ebx,ebx
    mov bl,[esi+1F82h]
    shl ebx,16
    mov bx,[esi+1F80h]
    add bx,bx
    shr ebx,1
    add ebx,[romdata]
    mov edi,ebx
    xor ecx,ecx
    mov cl,[esi+295h]
.loop
    xor eax,eax
    mov al,[esi+1F82h]
    shl eax,16
    mov al,[edi+1]
    mov ah,[edi+0]
    mov edx,edi
.nextprev
    cmp ax,0FFFFh
    jne .notprev
    sub edx,5
    mov al,[edx+3]
    mov ah,[edx+2]
    jmp .nextprev
.notprev
    add ax,ax
    shr eax,1
    add eax,[romdata]
    xor edx,edx
    mov dl,[esi+1F82h]
    shl edx,16
    mov dl,[edi+3]
    mov dh,[edi+2]
;    mov [C4values+6],dx
    add dx,dx
    shr edx,1
    add edx,[romdata]
    xor ebx,ebx
    mov bh,[eax]
    mov bl,[eax+1]
    mov [C4X1],ebx
    mov bh,[eax+2]
    mov bl,[eax+3]
    mov [C4Y1],ebx
    mov bh,[eax+4]
    mov bl,[eax+5]
    mov [C4Z1],ebx
    mov bh,[edx]
    mov bl,[edx+1]
    mov [C4X2],ebx
    mov bh,[edx+2]
    mov bl,[edx+3]
    mov [C4Y2],ebx
    mov bh,[edx+4]
    mov bl,[edx+5]
    mov [C4Z2],ebx
    mov al,[edi+4]
    mov [C4Col],al
    add edi,5
    call C4DrawLine
    dec ecx
    jnz near .loop
    ret

SECTION .data
C4X1 dd 0
C4Y1 dd 0
C4Z1 dd 0
C4X2 dd 0
C4Y2 dd 0
C4Z2 dd 0
C4Col dd 0
SECTION .text

WireFrameB:
    pushad
    ; 28EECA
    ; 7F80 (3bytes) = pointer to data
    ; 7F86-7F88 = rotation, 7F90 = scale (/7A?)
    ; 6295 = # of lines, 7FA5 = ???
    mov esi,[C4Ram]
    add esi,300h
    mov ecx,16*12*3
.loop
    mov dword[esi],0
    add esi,4
    loop .loop
    call DrawWireFrame

    mov esi,[C4Ram]
    mov cx,[esi+1FA5h]
;    mov [C4values],cx
;    mov cx,[esi+1F86h]
;    mov [C4values],cx
;    mov cx,[esi+1F88h]
;    mov [C4values+2],cx
;    mov cx,[esi+1F90h]
;    mov [C4values+4],cx
    popad
    ret

WireFrameB2:
    pushad
    call DrawWireFrame
    popad
    ret

C4WireFrame:
EXTSYM C4WFXVal,C4WFYVal,C4WFX2Val,C4WFY2Val,C4CalcWireFrame
EXTSYM C4WFDist,C4WFScale,C4TransfWireFrame,C4WFZVal
    pushad
    mov esi,[C4Ram]
    mov ax,[esi+1F83h]
    and ax,0FFh
    mov [C4WFX2Val],ax
;    mov [C4values],ax
    mov ax,[esi+1F86h]
    and ax,0FFh
    mov [C4WFY2Val],ax
;    mov [C4values+2],ax
    mov ax,[esi+1F89h]
    and ax,0FFh
    mov [C4WFDist],ax
;    mov [C4values+4],ax
    mov ax,[esi+1F8Ch]
    and ax,0FFh
    mov [C4WFScale],ax
;    mov [C4values+6],ax

    ; transform vertices (MMX2 - 36 vertices, 54 lines)
    xor ecx,ecx
    mov cx,[esi+1F80h]
    xor al,al
.loop
    mov ax,[esi+1]
    mov [C4WFXVal],ax
    mov ax,[esi+5]
    mov [C4WFYVal],ax
    mov ax,[esi+9]
    mov [C4WFZVal],ax
    push esi
    push ecx
    call C4TransfWireFrame
    pop ecx
    pop esi
    ; Displace
    mov ax,[C4WFXVal]
    add ax,80h
    mov [esi+1],ax
    mov ax,[C4WFYVal]
    add ax,50h
    mov [esi+5],ax
    add esi,10h
    loop .loop
    ; Uses 6001,6005,6600,6602,6605

    mov esi,[C4Ram]
    mov word[esi+$600],23
    mov word[esi+$602],60h
    mov word[esi+$605],40h
    mov word[esi+$600+8],23
    mov word[esi+$602+8],60h
    mov word[esi+$605+8],40h

    xor ecx,ecx
    mov cx,[esi+0B00h]
    mov edi,esi
    add edi,0B02h
.lineloop
    xor eax,eax
    mov al,[edi]
    shl eax,4
    add eax,[C4Ram]
    mov bx,[eax+1]
    mov [C4WFXVal],bx
    mov bx,[eax+5]
    mov [C4WFYVal],bx
    xor eax,eax
    mov al,[edi+1]
    shl eax,4
    add eax,[C4Ram]
    mov bx,[eax+1]
    mov [C4WFX2Val],bx
    mov bx,[eax+5]
    mov [C4WFY2Val],bx
    push esi
    push edi
    push ecx
    call C4CalcWireFrame
    pop ecx
    pop edi
    pop esi
    mov ax,[C4WFDist]
    or ax,ax
    jnz .yeswire
    mov ax,1
.yeswire
    mov word[esi+$600],ax
    mov ax,[C4WFXVal]
    mov word[esi+$602],ax
    mov ax,[C4WFYVal]
    mov word[esi+$605],ax
    add edi,2
    add esi,8
    dec ecx
    jnz near .lineloop
.done
    popad
    ret

C4Transform:
    ; 7F81,4,7,9,A,B,0,1,D
    pushad
    mov esi,[C4Ram]
    mov ax,word[esi+1F81h]
    mov [C4WFXVal],ax
    mov ax,word[esi+1F84h]
    mov [C4WFYVal],ax
    mov ax,word[esi+1F87h]
    mov [C4WFZVal],ax
    mov al,[esi+1F90h]
    mov [C4WFScale],al
    mov al,[esi+1F89h]
    mov [C4WFX2Val],al
    mov al,[esi+1F8Ah]
    mov [C4WFY2Val],al
    mov al,[esi+1F8Bh]
    mov [C4WFDist],al
EXTSYM C4TransfWireFrame2
    call C4TransfWireFrame2
    mov ax,[C4WFXVal]
    mov word[esi+1F80h],ax
    mov ax,[C4WFYVal]
    mov word[esi+1F83h],ax
    popad
    ret

SECTION .data
C4SprPos dd 0
C4SprScale dd 0
C4SprScaleY dd 0
C4SprScaler dd 0
C4SprScalerY dd 0
C4SprPtr dd 0
C4SprPtrInc dd 0
NEWSYM C4values, dd 0,0,0
SECTION .text

C4activate:
    cmp ecx,1F4Fh
    jne .noc4test
    push esi
    mov esi,[C4Ram]
    cmp byte[esi+1F4Dh],0Eh
    jne .befnoc4test
    test al,0C3h
    jnz .befnoc4test
    shr al,2