$Revision$
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Copyright (C) KolibriOS team 2004-2007. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License ;;
;; ;;
;; VESA20.INC ;;
;; ;;
;; Vesa 2.0 functions for MenuetOS ;;
;; ;;
;; Copyright 2002 Ville Turjanmaa ;;
;; Alexey, kgaz@crosswindws.net ;;
;; - Voodoo compatible graphics ;;
;; Juan M. Caravaca ;;
;; - Graphics optimimizations eg. drawline ;;
;; ;;
;; See file COPYING for details ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; If you're planning to write your own video driver I suggest
; you replace the VESA12.INC file and see those instructions.
;ScreenWidth equ 0xfe00
;ScreenHeight equ 0xfe04
;BytesPerScanLine equ 0xfe08
;LFBAddress equ 0xfe80
;ScreenBPP equ 0xfbf1
;WinMapAddress equ 0x460000
;*************************************************
; getpixel
;
; in:
; eax = x coordinate
; ebx = y coordinate
;
; ret:
; ecx = 00 RR GG BB
getpixel:
push eax ebx edx edi
call dword [GETPIXEL]
pop edi edx ebx eax
ret
Vesa20_getpixel24:
; eax = x
; ebx = y
imul ebx, [BytesPerScanLine] ; ebx = y * y multiplier
lea edi, [eax+eax*2] ; edi = x*3
add edi, ebx ; edi = x*3+(y*y multiplier)
add edi, [LFBAddress] ; ebx = where pixel is in memory
mov ecx, [edi]
and ecx, 0xffffff
ret
Vesa20_getpixel32:
imul ebx, [BytesPerScanLine] ; ebx = y * y multiplier
lea edi, [ebx+eax*4] ; edi = x*4+(y*y multiplier)
add edi, [LFBAddress] ; ebx = where pixel is in memory
mov ecx, [edi]
and ecx, 0xffffff
ret
;*************************************************
virtual at esp
putimg:
.real_sx dd ?
.real_sy dd ?
.image_sx dd ?
.image_sy dd ?
.image_cx dd ?
.image_cy dd ?
.pti dd ?
.abs_cx dd ?
.abs_cy dd ?
.line_increment dd ?
.winmap_newline dd ?
.screen_newline dd ?
.stack_data = 4*12
.edi dd ?
.esi dd ?
.ebp dd ?
.esp dd ?
.ebx dd ?
.edx dd ?
.ecx dd ?
.eax dd ?
.ret_addr dd ?
.arg_0 dd ?
end virtual
align 16
; ebx = pointer
; ecx = size [x|y]
; edx = coordinates [x|y]
; ebp = pointer to 'get' function
; esi = pointer to 'init' function
; edi = parameter for 'get' function
vesa20_putimage:
pushad
call [disable_mouse]
sub esp, putimg.stack_data
; save pointer to image
mov [putimg.pti], ebx
; unpack the size
mov eax, ecx
and ecx, 0xFFFF
shr eax, 16
mov [putimg.image_sx], eax
mov [putimg.image_sy], ecx
; unpack the coordinates
mov eax, edx
and edx, 0xFFFF
shr eax, 16
mov [putimg.image_cx], eax
mov [putimg.image_cy], edx
; calculate absolute (i.e. screen) coordinates
mov eax, [TASK_BASE]
mov ebx, [eax-twdw + WDATA.box.left]
add ebx, [putimg.image_cx]
mov [putimg.abs_cx], ebx
mov ebx, [eax-twdw + WDATA.box.top]
add ebx, [putimg.image_cy]
mov [putimg.abs_cy], ebx
; real_sx = MIN(wnd_sx-image_cx, image_sx);
mov ebx, [eax-twdw + WDATA.box.width] ; ebx = wnd_sx
; \begin{diamond}[20.08.2006]
; note that WDATA.box.width is one pixel less than real window x-size
inc ebx
; \end{diamond}[20.08.2006]
sub ebx, [putimg.image_cx]
ja @f
add esp, putimg.stack_data
popad
ret
@@:
cmp ebx, [putimg.image_sx]
jbe .end_x
mov ebx, [putimg.image_sx]
.end_x:
mov [putimg.real_sx], ebx
; init real_sy
mov ebx, [eax-twdw + WDATA.box.height] ; ebx = wnd_sy
; \begin{diamond}[20.08.2006]
inc ebx
; \end{diamond}[20.08.2006]
sub ebx, [putimg.image_cy]
ja @f
add esp, putimg.stack_data
popad
ret
@@:
cmp ebx, [putimg.image_sy]
jbe .end_y
mov ebx, [putimg.image_sy]
.end_y:
mov [putimg.real_sy], ebx
; line increment
mov eax, [putimg.image_sx]
sub eax, [putimg.real_sx]
;; imul eax, [putimg.source_bpp]
; lea eax, [eax + eax * 2]
call esi
add eax, [putimg.arg_0]
mov [putimg.line_increment], eax
; winmap new line increment
mov eax, [ScreenWidth]
inc eax
sub eax, [putimg.real_sx]
mov [putimg.winmap_newline], eax
; screen new line increment
mov eax, [BytesPerScanLine]
mov ecx, [putimg.real_sx]
movzx ebx, byte [ScreenBPP]
shr ebx, 3
imul ecx, ebx
sub eax, ecx
mov [putimg.screen_newline], eax
; pointer to image
mov esi, [putimg.pti]
; pointer to screen
mov edx, [putimg.abs_cy]
imul edx, [BytesPerScanLine]
mov eax, [putimg.abs_cx]
movzx ebx, byte [ScreenBPP]
shr ebx, 3
imul eax, ebx
add edx, eax
add edx, [LFBAddress]
; pointer to pixel map
mov eax, [putimg.abs_cy]
imul eax, [ScreenWidth]
add eax, [putimg.abs_cy]
add eax, [putimg.abs_cx]
add eax, WinMapAddress
xchg eax, ebp
; get process number
mov ebx, [CURRENT_TASK]
cmp byte [ScreenBPP], 32
je put_image_end_32
;put_image_end_24:
mov edi, [putimg.real_sy]
align 4
.new_line:
mov ecx, [putimg.real_sx]
; push ebp edx
align 4
.new_x:
push [putimg.edi]
mov eax, [putimg.ebp+4]
call eax
cmp [ebp], bl
jne .skip
; mov eax, [esi] ; eax = RRBBGGRR
mov [edx], ax
shr eax, 16
mov [edx+2], al
.skip:
; add esi, 3 ;[putimg.source_bpp]
add edx, 3
inc ebp
dec ecx
jnz .new_x
; pop edx ebp
add esi, [putimg.line_increment]
add edx, [putimg.screen_newline] ;[BytesPerScanLine]
add ebp, [putimg.winmap_newline] ;[ScreenWidth]
; inc ebp
dec edi
jnz .new_line
.finish:
add esp, putimg.stack_data
popad
ret
put_image_end_32:
mov edi, [putimg.real_sy]
align 4
.new_line:
mov ecx, [putimg.real_sx]
; push ebp edx
align 4
.new_x:
push [putimg.edi]
mov eax, [putimg.ebp+4]
call eax
cmp [ebp], bl
jne .skip
; mov eax, [esi] ; ecx = RRBBGGRR
mov [edx], eax
.skip:
; add esi, [putimg.source_bpp]
add edx, 4
inc ebp
dec ecx
jnz .new_x
; pop edx ebp
add esi, [putimg.line_increment]
add edx, [putimg.screen_newline] ;[BytesPerScanLine]
add ebp, [putimg.winmap_newline] ;[ScreenWidth]
; inc ebp
dec edi
jnz .new_line
.finish:
add esp, putimg.stack_data
popad
call VGA__putimage
mov [EGA_counter],1
ret
;*************************************************
align 4
__sys_putpixel:
; eax = x coordinate
; ebx = y coordinate
; ecx = ?? RR GG BB ; 0x01000000 negation
; edi = 0x00000001 force
;;; mov [novesachecksum], dword 0
pushad
test edi,1 ; force ?
jnz .forced
; not forced:
push ecx ; save 24th bit in case negative pixel wanted
call checkpixel
test ecx,ecx
pop ecx
jnz .exit
.forced:
cmp [ScreenWidth], eax
jb .exit
cmp [ScreenHeight], ebx
jb .exit
.ok:
; check if negation
test ecx,0x01000000
jz .noneg
call getpixel
not ecx
mov [esp+32-8],ecx
.noneg:
; OK to set pixel
call dword [PUTPIXEL] ; call the real put_pixel function
.exit:
popad
ret
align 4
Vesa20_putpixel24:
; eax = x
; ebx = y
imul ebx, [BytesPerScanLine] ; ebx = y * y multiplier
lea edi, [eax+eax*2] ; edi = x*3
mov eax, [esp+32-8+4]
add edi, [LFBAddress]
add edi, ebx ; ebx = where to put pixel in memory
mov [edi], ax
shr eax, 16
mov [edi+2], al
ret
align 4
Vesa20_putpixel32:
; eax = x
; ebx = y
imul ebx, [BytesPerScanLine] ; ebx = y * y multiplier
lea edi, [ebx+eax*4] ; edi = x*4+(y*y multiplier)
mov eax, [esp+32-8+4] ; eax = color
add edi, [LFBAddress] ; ebx = where to put pixel in memory
mov [edi], eax
ret
;*************************************************
;align 4
calculate_edi:
mov edi, ebx
imul edi, [ScreenWidth]
add edi, ebx
add edi, eax
ret
;*************************************************
; DRAWLINE
align 4
__sys_draw_line:
; inc [mouse_pause]
call [disable_mouse]
; draw a line
; eax = HIWORD = x1
; LOWORD = x2
; ebx = HIWORD = y1
; LOWORD = y2
; ecx = color
; edi = force ?
pusha
dl_x1 equ esp+20
dl_y1 equ esp+16
dl_x2 equ esp+12
dl_y2 equ esp+8
dl_dx equ esp+4
dl_dy equ esp+0
xor edx, edx ; clear edx
xor esi, esi ; unpack arguments
xor ebp, ebp
mov si, ax ; esi = x2
mov bp, bx ; ebp = y2
shr eax, 16 ; eax = x1
shr ebx, 16 ; ebx = y1
push eax ; save x1
push ebx ; save y1
push esi ; save x2
push ebp ; save y2
; checking x-axis...
sub esi, eax ; esi = x2-x1
push esi ; save y2-y1
jl .x2lx1 ; is x2 less than x1 ?
jg .no_vline ; x1 > x2 ?
mov edx, ebp ; else (if x1=x2)
call vline
push edx ; necessary to rightly restore stack frame at .exit
jmp .exit
.x2lx1:
neg esi ; get esi absolute value
.no_vline:
; checking y-axis...
sub ebp, ebx ; ebp = y2-y1
push ebp ; save y2-y1
jl .y2ly1 ; is y2 less than y1 ?
jg .no_hline ; y1 > y2 ?
mov edx, [dl_x2] ; else (if y1=y2)
call hline
jmp .exit
.y2ly1:
neg ebp ; get ebp absolute value
.no_hline:
cmp ebp, esi
jle .x_rules ; |y2-y1| < |x2-x1| ?
cmp [dl_y2], ebx ; make sure y1 is at the begining
jge .no_reverse1
neg dword [dl_dx]
mov edx, [dl_x2]
mov [dl_x2], eax
mov [dl_x1], edx
mov edx, [dl_y2]
mov [dl_y2], ebx
mov [dl_y1], edx
.no_reverse1:
mov eax, [dl_dx]
cdq ; extend eax sing to edx
shl eax, 16 ; using 16bit fix-point maths
idiv ebp ; eax = ((x2-x1)*65536)/(y2-y1)
mov edx, ebp ; edx = counter (number of pixels to draw)
mov ebp, 1 *65536 ; <<16 ; ebp = dy = 1.0
mov esi, eax ; esi = dx
jmp .y_rules
.x_rules:
cmp [dl_x2], eax ; make sure x1 is at the begining
jge .no_reverse2
neg dword [dl_dy]
mov edx, [dl_x2]
mov [dl_x2], eax
mov [dl_x1], edx
mov edx, [dl_y2]
mov [dl_y2], ebx
mov [dl_y1], edx
.no_reverse2:
xor edx, edx
mov eax, [dl_dy]
cdq ; extend eax sing to edx
shl eax, 16 ; using 16bit fix-point maths
idiv esi ; eax = ((y2-y1)*65536)/(x2-x1)
mov edx, esi ; edx = counter (number of pixels to draw)
mov esi, 1 *65536 ;<< 16 ; esi = dx = 1.0
mov ebp, eax ; ebp = dy
.y_rules:
mov eax, [dl_x1]
mov ebx, [dl_y1]
shl eax, 16
shl ebx, 16
align 4
.draw:
push eax ebx
shr eax, 16
shr ebx, 16
call [putpixel]
pop ebx eax
add ebx, ebp ; y = y+dy
add eax, esi ; x = x+dx
dec edx
jnz .draw
; force last drawn pixel to be at (x2,y2)
mov eax, [dl_x2]
mov ebx, [dl_y2]
call [putpixel]
.exit:
add esp, 6*4
popa
; dec [mouse_pause]
call [draw_pointer]
ret
hline:
; draw an horizontal line
; eax = x1
; edx = x2
; ebx = y
; ecx = color
; edi = force ?
push eax edx
cmp edx, eax ; make sure x2 is above x1
jge @f
xchg eax, edx
align 4
@@:
call [putpixel]
inc eax
cmp eax, edx
jle @b
pop edx eax
ret
vline:
; draw a vertical line
; eax = x
; ebx = y1
; edx = y2
; ecx = color
; edi = force ?
push ebx edx
cmp edx, ebx ; make sure y2 is above y1
jge @f
xchg ebx, edx
align 4
@@:
call [putpixel]
inc ebx
cmp ebx, edx
jle @b
pop edx ebx
ret
;*************************************************
virtual at esp
drbar:
.bar_sx dd ?
.bar_sy dd ?
.bar_cx dd ?
.bar_cy dd ?
.abs_cx dd ?
.abs_cy dd ?
.real_sx dd ?
.real_sy dd ?
.color dd ?
.line_inc_scr dd ?
.line_inc_map dd ?
.stack_data = 4*11
end virtual
align 4
; eax cx
; ebx cy
; ecx xe
; edx ye
; edi color
vesa20_drawbar:
pushad
call [disable_mouse]
sub esp, drbar.stack_data
mov [drbar.color], edi
sub edx, ebx
jle .exit ;// mike.dld, 2005-01-29
sub ecx, eax
jle .exit ;// mike.dld, 2005-01-29
mov [drbar.bar_sy], edx
mov [drbar.bar_sx], ecx
mov [drbar.bar_cx], eax
mov [drbar.bar_cy], ebx
mov edi, [TASK_BASE]
add eax, [edi-twdw + WDATA.box.left] ; win_cx
add ebx, [edi-twdw + WDATA.box.top] ; win_cy
mov [drbar.abs_cx], eax
mov [drbar.abs_cy], ebx
; real_sx = MIN(wnd_sx-bar_cx, bar_sx);
mov ebx, [edi-twdw + WDATA.box.width] ; ebx = wnd_sx
; \begin{diamond}[20.08.2006]
; note that WDATA.box.width is one pixel less than real window x-size
inc ebx
; \end{diamond}[20.08.2006]
sub ebx, [drbar.bar_cx]
ja @f
.exit: ;// mike.dld, 2005-01-29
add esp, drbar.stack_data
popad
xor eax, eax
inc eax
ret
@@:
cmp ebx, [drbar.bar_sx]
jbe .end_x
mov ebx, [drbar.bar_sx]
.end_x:
mov [drbar.real_sx], ebx
; real_sy = MIN(wnd_sy-bar_cy, bar_sy);
mov ebx, [edi-twdw + WDATA.box.height] ; ebx = wnd_sy
; \begin{diamond}[20.08.2006]
inc ebx
; \end{diamond}
sub ebx, [drbar.bar_cy]
ja @f
add esp, drbar.stack_data
popad
xor eax, eax
inc eax
ret
@@:
cmp ebx, [drbar.bar_sy]
jbe .end_y
mov ebx, [drbar.bar_sy]
.end_y:
mov [drbar.real_sy], ebx
; line_inc_map
mov eax, [ScreenWidth]
sub eax, [drbar.real_sx]
inc eax
mov [drbar.line_inc_map], eax
; line_inc_scr
mov eax, [drbar.real_sx]
movzx ebx, byte [ScreenBPP]
shr ebx, 3
imul eax, ebx
neg eax
add eax, [BytesPerScanLine]
mov [drbar.line_inc_scr], eax
; pointer to screen
mov edx, [drbar.abs_cy]
imul edx, [BytesPerScanLine]
mov eax, [drbar.abs_cx]
; movzx ebx, byte [ScreenBPP]
; shr ebx, 3
imul eax, ebx
add edx, eax
add edx, [LFBAddress]
; pointer to pixel map
mov eax, [drbar.abs_cy]
imul eax, [ScreenWidth]
add eax, [drbar.abs_cy]
add eax, [drbar.abs_cx]
add eax, WinMapAddress
xchg eax, ebp
; get process number
mov ebx, [CURRENT_TASK]
cmp byte [ScreenBPP], 24
jne draw_bar_end_32
draw_bar_end_24:
mov eax, [drbar.color] ;; BBGGRR00
mov bh, al ;; bh = BB
shr eax, 8 ;; eax = RRGG
; eax - color high RRGG
; bl - process num
; bh - color low BB
; ecx - temp
; edx - pointer to screen
; esi - counter
; edi - counter
mov esi, [drbar.real_sy]
align 4
.new_y:
mov edi, [drbar.real_sx]
align 4
.new_x:
cmp byte [ebp], bl
jne .skip
mov [edx], bh
mov [edx + 1], ax
.skip:
; add pixel
add edx, 3
inc ebp
dec edi
jnz .new_x
; add line
add edx, [drbar.line_inc_scr]
add ebp, [drbar.line_inc_map]
; drawing gradient bars
test eax, 0x00800000
jz @f
test bh, bh
jz @f
dec bh
@@:
;
dec esi
jnz .new_y
add esp, drbar.stack_data
popad
xor eax, eax
ret
draw_bar_end_32:
mov eax, [drbar.color] ;; BBGGRR00
mov esi, [drbar.real_sy]
align 4
.new_y:
mov edi, [drbar.real_sx]
align 4
.new_x:
cmp byte [ebp], bl
jne .skip
mov [edx], eax
.skip:
; add pixel
add edx, 4
inc ebp
dec edi
jnz .new_x
; add line
add edx, [drbar.line_inc_scr]
add ebp, [drbar.line_inc_map]
; drawing gradient bars
test eax, 0x80000000
jz @f
test al, al
jz @f
dec al
@@:
;
dec esi
jnz .new_y
add esp, drbar.stack_data
popad
call VGA_draw_bar
xor eax, eax
mov [EGA_counter],1
ret
;voodoodbcplimit:
; ebp:=(y+Ywin)*(ScreenXSize+1)+(x+Xwin)+AddrBuffer
; pusha
; xor edx,edx
; mov eax,ebp
; mov ebx,[ScreenWidth] ; Screen_X_size
; inc ebx ; +1
; sub eax,WinMapAddress ; -AddrBuffer
; div ebx ;
; mov ebx,eax ; ebx:=Y
; mov eax,edx ; eax:=X
; call cplimit
; test ecx,ecx
; jne dbcpl12
; popa
; clc
; ret
; dbcpl12:
; popa
; stc
; ret
;dbcplimit:
; pusha
; xor edx,edx
; mov ebx,[ScreenWidth]
; inc ebx
; sub eax,WinMapAddress
; div ebx
; mov ebx,eax
; mov eax,edx
; call cplimit
; test ecx,ecx
; jne dbcpl1
; popa
; clc
; ret
; dbcpl1:
; popa
; stc
; ret
vesa20_drawbackground_tiled:
call [disable_mouse]
pushad
; External loop for all y from start to end
mov ebx, [draw_data+32+RECT.top] ; y start
dp2:
mov ebp, [draw_data+32+RECT.left] ; x start
; 1) Calculate pointers in WinMapAddress (does pixel belong to OS thread?) [ebp]
; and LFB data (output for our function) [edi]
mov eax, [BytesPerScanLine]
mul ebx
xchg ebp, eax
add ebp, eax
add ebp, eax
add ebp, eax
cmp [ScreenBPP], byte 24 ; 24 or 32 bpp ? - x size
jz @f
add ebp, eax
@@:
add ebp, [LFBAddress]
; ebp:=Y*BytesPerScanLine+X*BytesPerPixel+AddrLFB
call calculate_edi
xchg edi, ebp
; Now eax=x, ebx=y, edi->output, ebp=offset in WinMapAddress
; 2) Calculate offset in background memory block
push eax
xor edx, edx
mov eax, ebx
mov ecx, [BgrDataHeight]
div ecx ; edx := y mod BgrDataHeight
sub ecx, edx ; ecx := BgrDataHeight - (y mod BgrDataHeight)
pop eax
push eax
mov esi, edx
imul esi, [BgrDataWidth] ; esi := (y mod BgrDataHeight) * BgrDataWidth
xor edx, edx
div dword [BgrDataWidth] ; edx := x mod BgrDataWidth
add esi, edx ; esi := (y mod BgrDataHeight)*BgrDataWidth + (x mod BgrDataWidth)
pop eax
lea esi, [esi*3]
add esi, [img_background]
xor edx, edx
inc edx
; 3) Loop through redraw rectangle and copy background data
; Registers meaning:
; eax = x, ebx = y (screen coordinates)
; ecx = deltax - number of pixels left in current tile block
; edx = 1
; esi -> bgr memory, edi -> output
; ebp = offset in WinMapAddress
dp3:
cmp [ebp+WinMapAddress], dl
jnz nbgp
movsb
movsb
movsb
jmp @f
nbgp:
add esi, 3
add edi, 3
@@:
cmp [ScreenBPP], byte 25 ; 24 or 32 bpp?
sbb edi, -1 ; +1 for 32 bpp
; I do not use 'inc eax' because this is slightly slower then 'add eax,1'
add ebp, edx
add eax, edx
cmp eax, [draw_data+32+RECT.right]
ja dp4
sub ecx, edx
jnz dp3
; next tile block on x-axis
mov ecx, [BgrDataWidth]
sub esi, ecx
sub esi, ecx
sub esi, ecx
jmp dp3
dp4:
; next scan line
inc ebx
cmp ebx, [draw_data+32+RECT.bottom]
jbe dp2
popad
mov [EGA_counter], 1
call VGA_drawbackground
ret
; ----------
vesa20_drawbackground_stretch:
call [disable_mouse]
pushad
; Helper variables
mov eax, [BgrDataWidth]
xor edx, edx
mov ecx, [ScreenWidth]
inc ecx
div ecx
push eax ; quo
push edx ; rem
mov eax, [BgrDataHeight]
xor edx, edx
mov ecx, [ScreenHeight]
inc ecx
div ecx
push eax
push edx
; External loop for all y from start to end
mov ebx, [draw_data+32+RECT.top] ; y start
mov ebp, [draw_data+32+RECT.left] ; x start
; 1) Calculate pointers in WinMapAddress (does pixel belong to OS thread?) [ebp]
; and LFB data (output for our function) [edi]
mov eax, [BytesPerScanLine]
mul ebx
xchg ebp, eax
add ebp, eax
add ebp, eax
add ebp, eax
cmp [ScreenBPP], byte 24 ; 24 or 32 bpp ? - x size
jz @f
add ebp, eax
@@:
add ebp, [LFBAddress]
; ebp:=Y*BytesPerScanLine+X*BytesPerPixel+AddrLFB
call calculate_edi
xchg edi, ebp
; Now eax=x, ebx=y, edi->output, ebp=offset in WinMapAddress
push ebx
; 2) Calculate offset in background memory block
push eax
mov eax, ebx
mul dword [BgrDataHeight]
mov ecx, [ScreenHeight]
inc ecx
div ecx ; eax := y * BgrDataHeight / ScreenHeight
; edx := (y * BgrDataHeight) mod ScreenHeight
mov esi, eax
pop eax
push edx ; dword [esp] = (y * BgrDataHeight) mod ScreenHeight
; dword [esp+4] = y * BgrDataHeight / ScreenHeight
push eax
mov ecx, [BgrDataWidth]
mul ecx
imul esi, ecx
dec ecx
push ecx
mov ecx, [ScreenWidth]
inc ecx
div ecx ; eax := x * BgrDataWidth / ScreenWidth
; edx := (x * BgrDataWidth) mod ScreenWidth
add esi, eax
lea esi, [esi*3]
add esi, [img_background]
push ecx edx esi
; 3) Loop through redraw rectangle and copy background data
; Registers meaning:
; ecx = (x * BgrDataWidth) / ScreenWidth
; edx = (x * BgrDataWidth) mod ScreenWidth (used to fast recalculating of ecx,esi)
; esi -> bgr memory, edi -> output
; ebp = offset in WinMapAddress
; dword [esp] = saved esi
; dword [esp+4] = saved edx
; dword [esp+8] = saved ecx
; dword [esp+12] = limit for overlapping of points
; dword [esp+16] = x
; dword [esp+20] = (y * BgrDataHeight) mod ScreenHeight (used to fast recalculating of esi)
; dword [esp+24] = y
; precalculated constants:
; dword [esp+28] = BgrDataHeight mod ScreenHeight
; dword [esp+32] = BgrDataHeight div ScreenHeight
; dword [esp+36] = BgrDataWidth mod ScreenWidth
; dword [esp+40] = BgrDataWidth div ScreenWidth
sdp3:
cmp [ebp+WinMapAddress], byte 1
jnz snbgp
mov al, [esi+2]
shl eax, 16
mov ax, [esi]
cmp ecx, [esp+12]
jae @f
mov ebx, [esi+2]
shr ebx, 8
call overlapping_of_points
@@:
mov [edi], ax
shr eax, 16
mov [edi+2], al
snbgp:
cmp [ScreenBPP], byte 25
sbb edi, -4
add ebp, 1
mov eax, [esp+16]
add eax, 1
mov [esp+16], eax
cmp eax, [draw_data+32+RECT.right]
ja sdp4
mov eax, [esp+40]
add ecx, eax
lea eax, [eax*3]
add esi, eax
add edx, [esp+36]
cmp edx, [ScreenWidth]
jbe sdp3
sub edx, [ScreenWidth]
add ecx, 1
add esi, 3
sub edx, 1
jmp sdp3
sdp4:
; next y
mov ebx, [esp+24]
add ebx, 1
mov [esp+24], ebx
cmp ebx, [draw_data+32+RECT.bottom]
ja sdpdone
; advance edi, ebp to next scan line
sub eax, [draw_data+32+RECT.left]
sub ebp, eax
add ebp, [ScreenWidth]
add ebp, 1
sub edi, eax
sub edi, eax
sub edi, eax
cmp [ScreenBPP], byte 24
jz @f
sub edi, eax
@@:
add edi, [BytesPerScanLine]
; restore ecx,edx; advance esi to next background line
pop esi edx ecx
push ecx edx
xor ebx, ebx
mov eax, [esp+20-4]
add eax, [esp+28-4]
cmp eax, [ScreenHeight]
jbe @f
sub eax, [ScreenHeight]
mov ebx, 1
sub eax, ebx
@@:
mov [esp+20-4], eax
add ebx, [esp+32-4]
lea ebx, [ebx*3]
imul ebx, [BgrDataWidth]
add esi, ebx
push esi
mov eax, [draw_data+32+RECT.left]
mov [esp+16], eax
jmp sdp3
sdpdone:
add esp, 44
popad
mov [EGA_counter],1
call VGA_drawbackground
ret
overlapping_of_points:
push ecx edx edi
mov ecx, eax
mov edx, ebx
movzx eax, cl
movzx ebx, dl
add eax, ebx
rcr eax, 1
movzx edi, ax
movzx eax, ch
movzx ebx, dh
add eax, ebx
rcr eax, 1
ror edi, 8
add edi, eax
shr ecx, 8
shr edx, 8
movzx eax, ch
movzx ebx, dh
add eax, ebx
rcr eax, 1
ror edi, 8
add eax, edi
ror eax, 16
pop edi edx ecx
ret