r_surf8.asm

著名游戏quake2原代码最新版本(vc6.0可以编译的)

 .386P
 .model FLAT
;
; surf8.s
; x86 assembly-language 8 bpp surface block drawing code.
;

include qasm.inc

if	id386

_DATA SEGMENT	

sb_v dd 0	

_DATA ENDS
_TEXT SEGMENT	

 align 4	
 public _R_Surf8Start	
_R_Surf8Start:	

;----------------------------------------------------------------------
; Surface block drawer for mip level 0
;----------------------------------------------------------------------

 align 4	
 public _R_DrawSurfaceBlock8_mip0	
_R_DrawSurfaceBlock8_mip0:	
 push ebp	; preserve caller's stack frame
 push edi	
 push esi	; preserve register variables
 push ebx	

;		for (v=0 ; v<numvblocks ; v++)
;		{
 mov ebx,ds:dword ptr[_r_lightptr]	
 mov eax,ds:dword ptr[_r_numvblocks]	

 mov ds:dword ptr[sb_v],eax	
 mov edi,ds:dword ptr[_prowdestbase]	

 mov esi,ds:dword ptr[_pbasesource]	

Lv_loop_mip0:	

;			lightleft = lightptr[0];
;			lightright = lightptr[1];
;			lightdelta = (lightleft - lightright) & 0xFFFFF;
 mov eax,ds:dword ptr[ebx]	; lightleft
 mov edx,ds:dword ptr[4+ebx]	; lightright

 mov ebp,eax	
 mov ecx,ds:dword ptr[_r_lightwidth]	

 mov ds:dword ptr[_lightright],edx	
 sub ebp,edx	

 and ebp,0FFFFFh	
 lea ebx,ds:dword ptr[ebx+ecx*4]	

;			lightptr += lightwidth;
 mov ds:dword ptr[_r_lightptr],ebx	

;			lightleftstep = (lightptr[0] - lightleft) >> blockdivshift;
;			lightrightstep = (lightptr[1] - lightright) >> blockdivshift;
;			lightdeltastep = ((lightleftstep - lightrightstep) & 0xFFFFF) |
;					0xF0000000;
 mov ecx,ds:dword ptr[4+ebx]	; lightptr[1]
 mov ebx,ds:dword ptr[ebx]	; lightptr[0]

 sub ebx,eax	
 sub ecx,edx	

 sar ecx,4	
 or ebp,0F0000000h	

 sar ebx,4	
 mov ds:dword ptr[_lightrightstep],ecx	

 sub ebx,ecx	
 and ebx,0FFFFFh	

 or ebx,0F0000000h	
 sub ecx,ecx	; high word must be 0 in loop for addressing

 mov ds:dword ptr[_lightdeltastep],ebx	
 sub ebx,ebx	; high word must be 0 in loop for addressing

Lblockloop8_mip0:	
 mov ds:dword ptr[_lightdelta],ebp	
 mov cl,ds:byte ptr[14+esi]	

 sar ebp,4	
 mov bh,dh	

 mov bl,ds:byte ptr[15+esi]	
 add edx,ebp	

 mov ch,dh	
 add edx,ebp	

 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch0:	
 mov bl,ds:byte ptr[13+esi]	

 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch1:	
 mov cl,ds:byte ptr[12+esi]	

 mov bh,dh	
 add edx,ebp	

 ror eax,16	
 mov ch,dh	

 add edx,ebp	
 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch2:	

 mov bl,ds:byte ptr[11+esi]	
 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch3:	

 mov cl,ds:byte ptr[10+esi]	
 mov ds:dword ptr[12+edi],eax	

 mov bh,dh	
 add edx,ebp	

 mov ch,dh	
 add edx,ebp	

 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch4:	
 mov bl,ds:byte ptr[9+esi]	

 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch5:	
 mov cl,ds:byte ptr[8+esi]	

 mov bh,dh	
 add edx,ebp	

 ror eax,16	
 mov ch,dh	

 add edx,ebp	
 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch6:	

 mov bl,ds:byte ptr[7+esi]	
 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch7:	

 mov cl,ds:byte ptr[6+esi]	
 mov ds:dword ptr[8+edi],eax	

 mov bh,dh	
 add edx,ebp	

 mov ch,dh	
 add edx,ebp	

 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch8:	
 mov bl,ds:byte ptr[5+esi]	

 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch9:	
 mov cl,ds:byte ptr[4+esi]	

 mov bh,dh	
 add edx,ebp	

 ror eax,16	
 mov ch,dh	

 add edx,ebp	
 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch10:	

 mov bl,ds:byte ptr[3+esi]	
 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch11:	

 mov cl,ds:byte ptr[2+esi]	
 mov ds:dword ptr[4+edi],eax	

 mov bh,dh	
 add edx,ebp	

 mov ch,dh	
 add edx,ebp	

 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch12:	
 mov bl,ds:byte ptr[1+esi]	

 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch13:	
 mov cl,ds:byte ptr[esi]	

 mov bh,dh	
 add edx,ebp	

 ror eax,16	
 mov ch,dh	

 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch14:	
 mov edx,ds:dword ptr[_lightright]	

 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch15:	
 mov ebp,ds:dword ptr[_lightdelta]	

 mov ds:dword ptr[edi],eax	

 add esi,ds:dword ptr[_sourcetstep]	
 add edi,ds:dword ptr[_surfrowbytes]	

 add edx,ds:dword ptr[_lightrightstep]	
 add ebp,ds:dword ptr[_lightdeltastep]	

 mov ds:dword ptr[_lightright],edx	
 jc Lblockloop8_mip0	

;			if (pbasesource >= r_sourcemax)
;				pbasesource -= stepback;

 cmp esi,ds:dword ptr[_r_sourcemax]	
 jb LSkip_mip0	
 sub esi,ds:dword ptr[_r_stepback]	
LSkip_mip0:	

 mov ebx,ds:dword ptr[_r_lightptr]	
 dec ds:dword ptr[sb_v]	

 jnz Lv_loop_mip0	

 pop ebx	; restore register variables
 pop esi	
 pop edi	
 pop ebp	; restore the caller's stack frame
 ret	


;----------------------------------------------------------------------
; Surface block drawer for mip level 1
;----------------------------------------------------------------------

 align 4	
 public _R_DrawSurfaceBlock8_mip1	
_R_DrawSurfaceBlock8_mip1:	
 push ebp	; preserve caller's stack frame
 push edi	
 push esi	; preserve register variables
 push ebx	

;		for (v=0 ; v<numvblocks ; v++)
;		{
 mov ebx,ds:dword ptr[_r_lightptr]	
 mov eax,ds:dword ptr[_r_numvblocks]	

 mov ds:dword ptr[sb_v],eax	
 mov edi,ds:dword ptr[_prowdestbase]	

 mov esi,ds:dword ptr[_pbasesource]	

Lv_loop_mip1:	

;			lightleft = lightptr[0];
;			lightright = lightptr[1];
;			lightdelta = (lightleft - lightright) & 0xFFFFF;
 mov eax,ds:dword ptr[ebx]	; lightleft
 mov edx,ds:dword ptr[4+ebx]	; lightright

 mov ebp,eax	
 mov ecx,ds:dword ptr[_r_lightwidth]	

 mov ds:dword ptr[_lightright],edx	
 sub ebp,edx	

 and ebp,0FFFFFh	
 lea ebx,ds:dword ptr[ebx+ecx*4]	

;			lightptr += lightwidth;
 mov ds:dword ptr[_r_lightptr],ebx	

;			lightleftstep = (lightptr[0] - lightleft) >> blockdivshift;
;			lightrightstep = (lightptr[1] - lightright) >> blockdivshift;
;			lightdeltastep = ((lightleftstep - lightrightstep) & 0xFFFFF) |
;					0xF0000000;
 mov ecx,ds:dword ptr[4+ebx]	; lightptr[1]
 mov ebx,ds:dword ptr[ebx]	; lightptr[0]

 sub ebx,eax	
 sub ecx,edx	

 sar ecx,3	
 or ebp,070000000h	

 sar ebx,3	
 mov ds:dword ptr[_lightrightstep],ecx	

 sub ebx,ecx	
 and ebx,0FFFFFh	

 or ebx,0F0000000h	
 sub ecx,ecx	; high word must be 0 in loop for addressing

 mov ds:dword ptr[_lightdeltastep],ebx	
 sub ebx,ebx	; high word must be 0 in loop for addressing

Lblockloop8_mip1:	
 mov ds:dword ptr[_lightdelta],ebp	
 mov cl,ds:byte ptr[6+esi]	

 sar ebp,3	
 mov bh,dh	

 mov bl,ds:byte ptr[7+esi]	
 add edx,ebp	

 mov ch,dh	
 add edx,ebp	

 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch22:	
 mov bl,ds:byte ptr[5+esi]	

 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch23:	
 mov cl,ds:byte ptr[4+esi]	

 mov bh,dh	
 add edx,ebp	

 ror eax,16	
 mov ch,dh	

 add edx,ebp	
 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch24:	

 mov bl,ds:byte ptr[3+esi]	
 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch25:	

 mov cl,ds:byte ptr[2+esi]	
 mov ds:dword ptr[4+edi],eax	

 mov bh,dh	
 add edx,ebp	

 mov ch,dh	
 add edx,ebp	

 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch26:	
 mov bl,ds:byte ptr[1+esi]	

 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch27:	
 mov cl,ds:byte ptr[esi]	

 mov bh,dh	
 add edx,ebp	

 ror eax,16	
 mov ch,dh	

 mov ah,ds:byte ptr[12345678h+ebx]	
LBPatch28:	
 mov edx,ds:dword ptr[_lightright]	

 mov al,ds:byte ptr[12345678h+ecx]	
LBPatch29:	
 mov ebp,ds:dword ptr[_lightdelta]	

 mov ds:dword ptr[edi],eax	
 mov eax,ds:dword ptr[_sourcetstep]	

 add esi,eax	
 mov eax,ds:dword ptr[_surfrowbytes]