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D3_DASM2.ASM
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D3_DASM2.ASM
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.386C
IDEAL
MODEL MEDIUM,C
;============================================================================
DATASEG
EXTRN mr_rowofs:WORD
EXTRN mr_count:WORD
EXTRN mr_xstep:WORD
EXTRN mr_ystep:WORD
EXTRN mr_xfrac:WORD
EXTRN mr_yfrac:WORD
EXTRN mr_dest:WORD
EXTRN jimflags:WORD
EXTRN shadingtable:DWORD
FARDATA
planepics db 8192 dup(?) ; // 4k of ceiling, 4k of floor
PUBLIC planepics
;============================================================================
CODESEG
;============================
;
; MapLSRow
;
;============================
PROC MapLSRow
PUBLIC MapLSRow
push esi
push edi
push ebp
push ds
mov ax,[WORD shadingtable + 2]
mov fs,ax
mov bp,[mr_rowofs]
mov cx,[mr_count]
mov dx,[mr_ystep]
shl edx,16
mov dx,[mr_xstep]
mov si,[mr_yfrac]
shl esi,16
mov si,[mr_xfrac]
mov di,[mr_dest]
mov ax,SEG planepics
mov ds,ax
mov ax,0a000h
mov es,ax
; eax and mask
; ebx scratch offset and pixel values
; ecx loop counter
; edx packed x / y step values
; esi packed x / y fractional values
; edi write pointer
; ebp toprow to bottomrow delta
; es: screenseg
; ds: pictures
@@pixelloop:
shld ebx,esi,22 ; shift y units in
shld ebx,esi,7 ; shift x units in and one extra bit
and bx,1111111111110b ; mask off extra top bits and 0 low bit
add esi,edx ; position += step
mov ax,[bx] ; get two source pixel
mov bx,ss:[WORD shadingtable]
mov bl,al ; map ceiling pixel
mov al,[fs:bx] ; map ceiling pixel
mov [es:di],al ; write ceiling pixel
mov bl,ah ; map floor pixel
mov ah,[fs:bx] ; map floor pixel
mov [es:di+bp],ah ; write floor pixel
inc di
loop @@pixelloop
pop ds
pop ebp
pop edi
pop esi
retf
ENDP
;============================
;
; F_MapLSRow
;
;============================
PROC F_MapLSRow
PUBLIC F_MapLSRow
push esi
push edi
push ebp
push ds
mov ax,[WORD shadingtable + 2]
mov fs,ax
mov bp,[mr_rowofs]
mov cx,[mr_count]
mov dx,[mr_ystep]
shl edx,16
mov dx,[mr_xstep]
mov si,[mr_yfrac]
shl esi,16
mov si,[mr_xfrac]
mov di,[mr_dest]
mov ax,SEG planepics
mov ds,ax
mov ax,0a000h
mov es,ax
; eax and mask
; ebx scratch offset and pixel values
; ecx loop counter
; edx packed x / y step values
; esi packed x / y fractional values
; edi write pointer
; ebp toprow to bottomrow delta
; es: screenseg
; ds: pictures
@@pixelloop:
shld ebx,esi,22 ; shift y units in
shld ebx,esi,7 ; shift x units in and one extra bit
and bx,1111111111110b ; mask off extra top bits and 0 low bit
add esi,edx ; position += step
mov ax,[bx] ; get two source pixel
mov bx,ss:[WORD shadingtable]
mov bl,ah ; map floor pixel
mov ah,[fs:bx] ; map floor pixel
mov [es:di+bp],ah ; write floor pixel
inc di
loop @@pixelloop
pop ds
pop ebp
pop edi
pop esi
retf
ENDP
;============================
;
; C_MapLSRow
;
;============================
PROC C_MapLSRow
PUBLIC C_MapLSRow
push esi
push edi
push ebp
push ds
mov ax,[WORD shadingtable + 2]
mov fs,ax
mov bp,[mr_rowofs]
mov cx,[mr_count]
mov dx,[mr_ystep]
shl edx,16
mov dx,[mr_xstep]
mov si,[mr_yfrac]
shl esi,16
mov si,[mr_xfrac]
mov di,[mr_dest]
mov ax,SEG planepics
mov ds,ax
mov ax,0a000h
mov es,ax
; eax and mask
; ebx scratch offset and pixel values
; ecx loop counter
; edx packed x / y step values
; esi packed x / y fractional values
; edi write pointer
; ebp toprow to bottomrow delta
; es: screenseg
; ds: pictures
@@pixelloop:
shld ebx,esi,22 ; shift y units in
shld ebx,esi,7 ; shift x units in and one extra bit
and bx,1111111111110b ; mask off extra top bits and 0 low bit
add esi,edx ; position += step
mov ax,[bx] ; get two source pixel
mov bx,ss:[WORD shadingtable]
mov bl,al ; map ceiling pixel
mov al,[fs:bx] ; map ceiling pixel
mov [es:di],al ; write ceiling pixel
inc di
loop @@pixelloop
pop ds
pop ebp
pop edi
pop esi
retf
ENDP
;============================
;
; MapRow
;
;============================
PROC MapRow
PUBLIC MapRow
push esi
push edi
push ebp
push ds
mov bp,[mr_rowofs]
mov cx,[mr_count]
mov dx,[mr_ystep]
shl edx,16
mov dx,[mr_xstep]
mov si,[mr_yfrac]
shl esi,16
mov si,[mr_xfrac]
mov di,[mr_dest]
mov ax,SEG planepics
mov ds,ax
mov ax,0a000h
mov es,ax
; eax and mask
; ebx scratch offset and pixel values
; ecx loop counter
; edx packed x / y step values
; esi packed x / y fractional values
; edi write pointer
; ebp toprow to bottomrow delta
; es: screenseg
; ds: pictures
@@pixelloop:
shld ebx,esi,22 ; shift y units in
shld ebx,esi,7 ; shift x units in and one extra bit
and bx,1111111111110b ; mask off extra top bits and 0 low bit
add esi,edx ; position += step
mov ax,[bx] ; get two source pixel
mov [es:di],al ; write ceiling pixel
mov [es:di+bp],ah ; write floor pixel
inc di
loop @@pixelloop
pop ds
pop ebp
pop edi
pop esi
retf
ENDP
;============================
;
; F_MapRow
;
;============================
PROC F_MapRow
PUBLIC F_MapRow
push esi
push edi
push ebp
push ds
mov bp,[mr_rowofs]
mov cx,[mr_count]
mov dx,[mr_ystep]
shl edx,16
mov dx,[mr_xstep]
mov si,[mr_yfrac]
shl esi,16
mov si,[mr_xfrac]
mov di,[mr_dest]
mov ax,SEG planepics
mov ds,ax
mov ax,0a000h
mov es,ax
; eax and mask
; ebx scratch offset and pixel values
; ecx loop counter
; edx packed x / y step values
; esi packed x / y fractional values
; edi write pointer
; ebp toprow to bottomrow delta
; es: screenseg
; ds: pictures
@@pixelloop:
shld ebx,esi,22 ; shift y units in
shld ebx,esi,7 ; shift x units in and one extra bit
and bx,1111111111110b ; mask off extra top bits and 0 low bit
add esi,edx ; position += step
mov ax,[bx] ; get two source pixel
mov [es:di+bp],ah ; write floor pixel
inc di
loop @@pixelloop
pop ds
pop ebp
pop edi
pop esi
retf
ENDP
;============================
;
; C_MapRow
;
;============================
PROC C_MapRow
PUBLIC C_MapRow
push esi
push edi
push ebp
push ds
mov bp,[mr_rowofs]
mov cx,[mr_count]
mov dx,[mr_ystep]
shl edx,16
mov dx,[mr_xstep]
mov si,[mr_yfrac]
shl esi,16
mov si,[mr_xfrac]
mov di,[mr_dest]
mov ax,SEG planepics
mov ds,ax
mov ax,0a000h
mov es,ax
; eax and mask
; ebx scratch offset and pixel values
; ecx loop counter
; edx packed x / y step values
; esi packed x / y fractional values
; edi write pointer
; ebp toprow to bottomrow delta
; es: screenseg
; ds: pictures
@@pixelloop:
shld ebx,esi,22 ; shift y units in
shld ebx,esi,7 ; shift x units in and one extra bit
and bx,1111111111110b ; mask off extra top bits and 0 low bit
add esi,edx ; position += step
mov ax,[bx] ; get two source pixel
mov [es:di],al ; write ceiling pixel
inc di
loop @@pixelloop
pop ds
pop ebp
pop edi
pop esi
retf
ENDP
END