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R2IMGASM.ASM
executable file
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R2IMGASM.ASM
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.486
.MODEL flat
LOCALS
.DATA
EXTRN _PITCH:DWORD,_SCREENX:DWORD,_SCREENY:DWORD
IMG STRUC
type dd 2
size dd ?
xw dd ?
yw dd ?
IMG ENDS
.CODE
PUBLIC _drawimager2,_loadpalette8,_loadpalette6,_drawrect,_drawrectmap
PUBLIC _drawhline,_drawvline,_drawscr
;;QUAD PALETTES!!!!!
;sets an 6-bit palette
_loadpalette6 PROC NEAR
ARG @@PAL:DWORD,@@FIRST:DWORD,@@CNT:DWORD
push ebp
mov ebp,esp
push esi
mov esi,@@PAL
mov eax,@@FIRST
mov ecx,@@CNT
mov edx,3C8h
out dx,al ;Set first
inc dx
@@LP: mov al,[esi+2]
out dx,al
mov al,[esi+1]
out dx,al
mov al,[esi+0]
out dx,al
add esi,4
dec ecx
jnz @@LP
pop esi
pop ebp
ret
_loadpalette6 ENDP
;sets a 8-bit palette (converting it to 6bit)
_loadpalette8 PROC NEAR
ARG @@PAL:DWORD,@@FIRST:DWORD,@@CNT:DWORD
push ebp
mov ebp,esp
push esi
mov esi,@@PAL
mov eax,@@FIRST
mov ecx,@@CNT
mov edx,3C8h
out dx,al ;Set first
cld
inc dx
@@LP: mov al,[esi+2]
shr al,2
out dx,al
mov al,[esi+1]
shr al,2
out dx,al
mov al,[esi+0]
shr al,2
out dx,al
add esi,4
dec ecx
jnz @@LP
pop esi
pop ebp
ret
_loadpalette8 ENDP
;void drawimager2(IMG *src,char *dest,int x,int y,int o)
_drawimager2 PROC
ARG @@SRC,@@DEST,@@X,@@Y,@@O
push ebp
mov ebp,esp
push ebx
push esi
push edi
mov esi,[@@SRC] ;source IMG
mov edi,[@@DEST] ;dest
test esi,esi
jz @@DONE
;do clip testing
xor eax,eax
mov ecx,@@X
mov edx,@@Y
add ecx,[esi.xw] ;right extent of image
add edx,[esi.yw] ;bottom extent of image
cmp [@@X],eax ;left clip
jl drawimager2clip
cmp [_SCREENX],ecx ;right clip
jl drawimager2clip
cmp [@@Y],eax ;top clip
jl drawimager2clip
cmp [_SCREENY],edx ;bottom clip
jl drawimager2clip
;point to memory for dest
mov eax,_PITCH
mul @@Y
add eax,@@X
add edi,eax
;test x flip
test [@@O],2
jnz @@XFLIP
call drawr2
jmp @@DONE
@@XFLIP:call drawr2_xflip
@@DONE:
pop edi
pop esi
pop ebx
pop ebp
ret
_drawimager2 ENDP
;image drawing prep function
;determines clipping values and calls clip core function
drawimager2clip PROC
ARG @@SRC,@@DEST,@@X,@@Y,@@O
xor ebx,ebx
;top clip
xor eax,eax
cmp [@@Y],eax
jg @@NOTOP
cmp edx,eax ;top edge is <0
jle @@DONE
sub eax,@@Y ;ystart=0-Y
mov @@Y,ebx ;Y=0
@@NOTOP: push eax ;store YSTART
;bottom clip
mov eax,[esi.yw]
sub edx,[_SCREENY]
jle @@NOBOTTOM
sub eax,edx ;ylen=SCREENY-Y
jle @@DONE
@@NOBOTTOM:
sub eax,[esp] ;ylen-=ystart
push eax ;store YLEN
;left clip
xor eax,eax
cmp [@@X],eax
jg @@NOLEFT
cmp ecx,eax ;right edge is <0
jle @@DONE
sub eax,@@X ;xstart=0-X
mov [@@X],ebx ;X=0
@@NOLEFT: push eax ;store XSTART
;right clip
mov eax,[esi.xw]
sub ecx,[_SCREENX]
jle @@NORIGHT
sub eax,ecx
jle @@DONE
@@NORIGHT:
sub eax,[esp] ;xlen-=xstart
push eax ;store XLEN
push @@O
;point to memory for dest
mov eax,_PITCH
push eax
mul @@Y
add eax,@@X
add edi,eax
;test x flip
test [@@O],2
jnz @@XFLIP
call drawr2_xyclip
jmp @@DONE
@@XFLIP:call drawr2_xyclip_xflip
@@DONE: lea esp,[ebp-3*4]
pop edi
pop esi
pop ebx
pop ebp
ret
drawimager2clip ENDP
;-------------------------------------------------
;core image drawing routine
;no clipping
;y flipping
drawr2 PROC
ARG @@SRC,@@DEST,@@X,@@Y,@@O
;negate diskip if yflip
mov eax,@@O
mov ebp,_PITCH
test eax,1b ;yflip
jz @@NOYFLIP
mov eax,[esi.yw] ;ywidth
dec eax
mul ebp
add edi,eax ;point to last scanline
neg ebp
@@NOYFLIP:
;get image dimensions
mov ebx,[esi.xw] ;xwidth
mov edx,[esi.yw] ;ywidth
sub ebp,ebx ;ebp=diskip
xor eax,eax
xor ecx,ecx
;point to data
lea esi,[esi+edx*4+16]
@@YLOOP:
push ebx ;save xwidth
@@XLOOP:
;transparent
mov al,[esi]
inc esi
add edi,eax
sub ebx,eax
jle @@DONELINE
;opaque
mov al,[esi]
inc esi
xor ecx,ecx
sub ebx,eax
;---------------------------------
;copy forward esi->edi, eax bytes ecx=0
sub ecx,edi ;amount to pre-copy
and ecx, 3
sub eax, ecx
jle short @@ENDCOPY
rep movsb
mov ecx, eax ;main copy
and eax, 3
shr ecx, 2
rep movsd
@@ENDCOPY: add ecx, eax ;end copy
xor eax,eax
rep movsb
;done copy
;--------------------------------
test ebx,ebx
jg @@XLOOP
@@DONELINE:
pop ebx ;restore xwidth
add edi,ebp ;position to next line
dec edx
jnz @@YLOOP
ret
@@DONE: pop ebx
ret
drawr2 ENDP
;core image drawing routine
;no clipping
;y flipping
drawr2_xflip PROC
ARG @@SRC,@@DEST,@@X,@@Y,@@O
;negate diskip if yflip
mov eax,@@O
mov ebp,_PITCH
test eax,1b ;yflip
jz @@NOYFLIP
mov eax,[esi.yw] ;ywidth
dec eax
mul ebp
add edi,eax ;point to last scanline
neg ebp
@@NOYFLIP:
;get image dimensions
mov ebx,[esi.xw] ;xwidth
mov edx,[esi.yw] ;ywidth
;point to data
lea esi,[esi+edx*4+16]
add ebp,ebx ;ebp=diskip (add cause we're flipped)
add edi,ebx ;point to end of scanline to copy leftwards
xor eax,eax
xor ecx,ecx
@@YLOOP:
push ebx ;save xwidth
@@XLOOP:
;transparent
mov al,[esi]
inc esi
sub edi,eax
sub ebx,eax
jle @@DONELINE
;opaque
mov al,[esi]
inc esi
sub ebx,eax
;copy backward esi->edi, ecx bytes
;@@COPY: dec edi
; mov al,[esi]
; inc esi
; mov [edi],al
; dec ecx
; jnz @@COPY
;;;backwards memory copy! esi->~edi ecx=count
;;precopy
mov ecx,edi
and ecx, 3
jz @@NOC1
sub eax, ecx
jle short @@LEndBytes
push eax
@@C1: dec edi
mov al,[esi] ; rep movsb
inc esi
mov [edi],al
dec ecx
jg @@C1
pop eax
;;copy
@@NOC1: mov ecx, eax
and eax, 3
shr ecx, 2
jz @@LEndBytes ;rep movsd
push eax
@@COPY: sub edi,4
mov eax,[esi]
add esi,4
bswap eax
dec ecx
mov [edi],eax
jnz @@COPY
pop eax
;;postcopy
@@LEndBytes: add ecx, eax
jle @@DONEC3 ; rep movsb
@@C3: dec edi
mov al,[esi] ; rep movsb
inc esi
mov [edi],al
dec ecx
jg @@C3
@@DONEC3:
;;------------------------------------
xor eax,eax
test ebx,ebx
jg @@XLOOP
@@DONELINE:
pop ebx ;restore xwidth
add edi,ebp ;position to next line
dec edx
jnz @@YLOOP
ret
@@DONE: pop ebx
ret
drawr2_xflip ENDP
;core image drawing routine
;xy clipping
;y flipping
drawr2_xyclip PROC
ARG @@DISKIP,@@O,@@XLEN,@@XSTART,@@YLEN,@@YSTART
push ebp
mov ebp,esp
;negate diskip if yflip
mov eax,@@O
test eax,1b ;yflip
jz @@NOYFLIP
mov eax,[esi.yw]
sub eax,@@YLEN
sub eax,@@YSTART
mov @@YSTART,eax
mov eax,[@@YLEN] ;ywidth
dec eax
mul [@@DISKIP]
add edi,eax ;point to last scanline
neg [@@DISKIP]
@@NOYFLIP:
xor eax,eax
xor ecx,ecx
push esi ;save @@SRC
@@YLOOP:
;point to source scanline
pop esi ;esi=@@SRC
mov ebx,[@@YSTART]
push esi
add esi,[esi+ebx*4+16]
inc [@@YSTART]
;get image dimensions
mov ebx,@@XLEN ;number of pixels to draw horizontally
mov edx,@@XSTART ;number of pixels to skip per scanline before drawing
push edi ;save dest
@@XLOOP:
;------------------------------------------------
;skip through XSTART
test edx,edx
jle @@PHASE2
@@PHASE1:
;transparent
@@T1: mov al,[esi]
inc esi
sub edx,eax
jle @@T1DONE
;opaque
@@O1: mov al,[esi]
inc esi
add esi,eax
sub edx,eax
jg @@PHASE1
;opaque phase 1 completed
xor ecx,ecx
add esi,edx ;scoot back left
sub ecx,edx ;eax=-edx (amt left to copy)
jmp @@O2
@@T1DONE: ;transparent phase 1 completed
sub edi,edx
add ebx,edx
jle @@DONELINE
mov cl,[esi] ;resume at opaque phase2
inc esi
jmp @@O2
;------------------------------------------------
;draw through XLEN
@@PHASE2:
;transparent
mov al,[esi]
inc esi
add edi,eax
sub ebx,eax
jle @@DONELINE
;opaque
mov cl,[esi]
inc esi
@@O2: sub ebx,ecx ;if ebx<0 ecx+=ebx
jg @@NORIGHTCLIP
add ecx,ebx
@@NORIGHTCLIP:
; rep movsb
;---------------------------------
;copy forward esi->edi, eax bytes ecx=0
mov eax,ecx
sub ecx,edi ;amount to pre-copy
sub ecx,eax
and ecx, 3
sub eax, ecx
jle short @@ENDCOPY
rep movsb
mov ecx, eax ;main copy
and eax, 3
shr ecx, 2
rep movsd
@@ENDCOPY: add ecx, eax ;end copy
xor eax,eax
rep movsb
;done copy
;--------------------------------
test ebx,ebx
jg @@PHASE2
@@DONELINE:
pop edi ;restore dest
add edi,@@DISKIP ;position to next line
dec [@@YLEN]
jnz @@YLOOP
@@DONE: pop esi
pop ebp
ret 6*4 ;return and pop
drawr2_xyclip ENDP
;core image drawing routine
;xy clipping
;xy flipping
drawr2_xyclip_xflip PROC
ARG @@DISKIP,@@O,@@XLEN,@@XSTART,@@YLEN,@@YSTART
push ebp
mov ebp,esp
mov eax,[esi.xw] ;ax=xlength
sub eax,@@XLEN
sub eax,@@XSTART
mov @@XSTART,eax
;negate diskip if yflip
mov eax,@@O
test eax,1b ;yflip
jz @@NOYFLIP
mov eax,[esi.yw]
sub eax,@@YLEN
sub eax,@@YSTART
mov @@YSTART,eax
mov eax,[@@YLEN] ;ywidth
dec eax
mul [@@DISKIP]
add edi,eax ;point to last scanline
neg [@@DISKIP]
@@NOYFLIP:
xor eax,eax
xor ecx,ecx
add edi,@@XLEN ;point to end of scanline to copy leftwards
push esi ;save @@SRC
@@YLOOP:
;point to source scanline
pop esi ;esi=@@SRC
mov ebx,[@@YSTART]
push esi
add esi,[esi+ebx*4+16]
inc [@@YSTART]
;get image dimensions
mov ebx,@@XLEN ;number of pixels to draw horizontally
mov edx,@@XSTART ;number of pixels to skip per scanline before drawing
push edi ;save dest
@@XLOOP:
;------------------------------------------------
;skip through XSTART
test edx,edx
jle @@PHASE2
@@PHASE1:
;transparent
@@T1: mov al,[esi]
inc esi
sub edx,eax
jle @@T1DONE
;opaque
@@O1: mov al,[esi]
inc esi
add esi,eax
sub edx,eax
jg @@PHASE1
;opaque phase 1 completed
xor ecx,ecx
add esi,edx ;scoot back left
sub ecx,edx ;eax=-edx (amt left to copy)
jmp @@O2
@@T1DONE: ;transparent phase 1 completed
add edi,edx
add ebx,edx
jle @@DONELINE
mov cl,[esi] ;resume at opaque phase2
inc esi
jmp @@O2
;------------------------------------------------
;draw through XLEN
@@PHASE2:
;transparent
mov al,[esi]
inc esi
sub edi,eax
sub ebx,eax
jle @@DONELINE
;opaque
mov cl,[esi]
inc esi
@@O2: sub ebx,ecx ;if ebx<0 ecx+=ebx
jg @@NORIGHTCLIP
add ecx,ebx
@@NORIGHTCLIP:
test ecx,ecx
jle @@NOCOPY
;copy backward esi->edi, ecx bytes
@@COPY: dec edi
mov al,[esi]
inc esi
mov [edi],al
dec ecx
jnz @@COPY
@@NOCOPY:
test ebx,ebx
jg @@PHASE2
@@DONELINE:
pop edi ;restore dest
add edi,@@DISKIP ;position to next line
dec [@@YLEN]
jnz @@YLOOP
@@DONE: pop esi
pop ebp
ret 6*4 ;return and pop
drawr2_xyclip_xflip ENDP
_drawhline PROC
ARG @@DEST,@@COLOR,@@X,@@Y,@@X2
push ebp
mov ebp,esp
push edi
;vertical clipping
mov eax,@@Y
test eax,eax
jl @@DONE
cmp eax,_SCREENY
jge @@DONE
mov eax,@@X
cmp eax,_SCREENX
jge @@DONE
test eax,eax
jge @@NOLEFTCLIP
xor eax,eax
@@NOLEFTCLIP:
mov ecx,@@X2
test ecx,ecx
jl @@DONE
cmp ecx,_SCREENX
jl @@NORIGHTCLIP
mov ecx,_SCREENX
dec ecx
@@NORIGHTCLIP:
;inc ecx
sub ecx,eax ;;get length
jle @@DONE
;get pointer to dest
mov edi,@@DEST
add edi,eax
mov eax,@@Y
mul _PITCH
add edi,eax
;set up storing word
mov al,byte ptr @@COLOR
mov ah,al
mov edx,eax
shl eax,16
mov ax,dx
; rep stosb
;---------------------------------
;copy forward esi->edi, eax bytes ecx=0
mov edx,ecx
sub ecx,edi ;amount to pre-copy
sub ecx,edx
and ecx, 3
sub edx, ecx
jle short @@ENDCOPY
rep stosb
mov ecx, edx ;main copy
and edx, 3
shr ecx, 2
rep stosd
@@ENDCOPY: add ecx, edx ;end copy
rep stosb
;done store
;--------------------------------
@@DONE:
pop edi
pop ebp
ret
_drawhline ENDP
_drawvline PROC
ARG @@DEST,@@COLOR,@@X,@@Y,@@Y2
push ebp
mov ebp,esp
push edi
;horiz clipping
mov eax,@@X
test eax,eax
jl @@DONE
cmp eax,_SCREENX
jge @@DONE
mov eax,@@Y
cmp eax,_SCREENY
jg @@DONE
test eax,eax
jg @@NOTOPCLIP
xor eax,eax
@@NOTOPCLIP:
mov ecx,@@Y2
test ecx,ecx
jl @@DONE
cmp ecx,_SCREENY
jl @@NOBOTTOMCLIP
mov ecx,_SCREENY
dec ecx
@@NOBOTTOMCLIP:
;inc ecx
sub ecx,eax ;;get length
jle @@DONE
;get pointer to dest
mov edi,@@DEST
mul _PITCH
add edi,eax
add edi,@@X
;set up storing word
mov al,byte ptr @@COLOR
mov edx,[_PITCH]
@@LP: mov [edi],al
add edi,edx
dec ecx
jnz @@LP
@@DONE:
pop edi
pop ebp
ret
_drawvline ENDP
_drawrect PROC
ARG @@B:DWORD,@@COLOR:DWORD,@@X:DWORD,@@Y:DWORD,@@XW:DWORD,@@YW:DWORD
push ebp
mov ebp,esp
push ebx
push edi
mov eax,_SCREENX
cmp [@@X],eax
jge @@DONE
mov eax,_SCREENY
cmp [@@Y],eax
jge @@DONE
mov eax,_SCREENX
mov ebx,@@X
add ebx,@@XW
cmp ebx,eax
jl @@NOXO
sub eax,@@X
mov @@XW,eax
@@NOXO:
mov eax,_SCREENY
mov ebx,@@Y
add ebx,@@YW
cmp ebx,eax
jl @@NOYO
sub eax,@@Y
mov @@YW,eax
@@NOYO:
cmp @@X,0
jge @@NOXU
mov eax,@@X
add [@@XW],eax
mov @@X,0
@@NOXU:
cmp @@Y,0
jge @@NOYU
mov eax,@@Y
add [@@YW],eax
mov @@Y,0
@@NOYU:
cmp [@@XW],0
jle @@DONE
cmp [@@YW],0
jle @@DONE
mov eax,@@Y
mul _PITCH
add eax,@@X
mov edi,@@B
add edi,eax
mov ebx,@@COLOR
mov al,bl
shl eax,8
mov al,bl
shl eax,8
mov al,bl
shl eax,8
mov al,bl
cld
@@YLOOP:
mov ecx, @@XW
;---------------------------------
;copy forward esi->edi, eax bytes ecx=0
mov edx,ecx
sub ecx,edi ;amount to pre-copy
sub ecx,edx
and ecx, 3
sub edx, ecx
jle short @@ENDCOPY
rep stosb
mov ecx, edx ;main copy
and edx, 3
shr ecx, 2
rep stosd
@@ENDCOPY: add ecx, edx ;end copy
rep stosb
;done store
;--------------------------------
add edi,_PITCH
sub edi,@@XW
dec @@YW
jg @@YLOOP
@@DONE:
pop edi
pop ebx
pop ebp
ret
_drawrect ENDP
;draw rectangle with color mapping
_drawrectmap PROC
ARG @@B:DWORD,@@MAP:DWORD,@@X:DWORD,@@Y:DWORD,@@XW:DWORD,@@YW:DWORD
push ebp
mov ebp,esp
push ebx
push esi
push edi
mov eax,_SCREENX
cmp [@@X],eax
jge @@DONE
mov eax,_SCREENY
cmp [@@Y],eax
jge @@DONE
mov eax,_SCREENX
mov ebx,@@X
add ebx,@@XW
cmp ebx,eax
jl @@NOXO
sub eax,@@X
mov @@XW,eax
@@NOXO:
mov eax,_SCREENY
mov ebx,@@Y
add ebx,@@YW
cmp ebx,eax
jl @@NOYO
sub eax,@@Y
mov @@YW,eax
@@NOYO:
cmp @@X,0
jge @@NOXU
mov eax,@@X
add [@@XW],eax
mov @@X,0
@@NOXU:
cmp @@Y,0
jge @@NOYU
mov eax,@@Y
add [@@YW],eax
mov @@Y,0
@@NOYU:
cmp [@@XW],0