WebSVN – Kolibri OS – Diff – /kernel/trunk/video/vesa20.inc

-$Revision: 536 $
+$Revision: 546 $
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;                                                              ;;
 ;; Copyright (C) KolibriOS team 2004-2007. All rights reserved. ;;
 ;; Distributed under terms of the GNU General Public License    ;;
 ;;                                                              ;;
 vesa20_drawbackground_stretch:
         call    [disable_mouse]
         pushad
+; Helper variables
-; Helper variables
+; calculate 2^32*(BgrDataWidth-1) mod (ScreenWidth-1)
+        mov     eax, [BgrDataWidth]
-        mov     eax, [BgrDataWidth]
+        dec     eax
         xor     edx, edx
-        mov     ecx, [ScreenWidth]
+        div     dword [ScreenWidth]
-        inc     ecx
+        push    eax     ; high
-        div     ecx
+        xor     eax, eax
-        push    eax     ; quo
+        div     dword [ScreenWidth]
+        push    eax     ; low
-        push    edx     ; rem
+; the same for height
+        mov     eax, [BgrDataHeight]
-        mov     eax, [BgrDataHeight]
+        dec     eax
         xor     edx, edx
-        mov     ecx, [ScreenHeight]
+        div     dword [ScreenHeight]
-        inc     ecx
+        push    eax     ; high
-        div     ecx
+        xor     eax, eax
-        push    eax
+        div     dword [ScreenHeight]
-        push    edx
+        push    eax     ; low
 ; 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]
 ; 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
+; 2) Calculate offset in background memory block
         mov     eax, ebx
-        mul     dword [BgrDataHeight]
+        imul    ebx, dword [esp+12]
-        mov     ecx, [ScreenHeight]
+        mul     dword [esp+8]
-        inc     ecx
-        div     ecx             ; eax := y * BgrDataHeight / ScreenHeight
+        add     edx, ebx        ; edx:eax = y * 2^32*(BgrDataHeight-1)/(ScreenHeight-1)
-                                ; edx := (y * BgrDataHeight) mod ScreenHeight
-        mov     esi, eax
+        mov     esi, edx
-        pop     eax
-        push    edx             ; dword [esp] = (y * BgrDataHeight) mod ScreenHeight
-                                ; dword [esp+4] = y * BgrDataHeight / ScreenHeight
-        push    eax
-        mov     ecx, [BgrDataWidth]
+        imul    esi, [BgrDataWidth]
-        lea     edx, [ecx*3]
-        imul    edx, [BgrDataHeight]
-        add     edx, [img_background]
         push    edx
-        mul     ecx
+        push    eax
-        imul    esi, ecx
+        mov     eax, [esp+8]
-        dec     ecx
+        mul     dword [esp+28]
-        push    ecx
+        push    eax
-        mov     ecx, [ScreenWidth]
+        mov     eax, [esp+12]
-        inc     ecx
+        mul     dword [esp+28]
-        div     ecx             ; eax := x * BgrDataWidth / ScreenWidth
+        add     [esp], edx
-                                ; edx := (x * BgrDataWidth) mod ScreenWidth
+        pop     edx             ; edx:eax = x * 2^32*(BgrDataWidth-1)/(ScreenWidth-1)
-        add     esi, eax
+        add     esi, edx
         lea     esi, [esi*3]
         add     esi, [img_background]
+        mov     ecx, eax
-        push    ecx edx esi
+        push    eax edx esi
 ; 3) Loop through redraw rectangle and copy background data
 ; Registers meaning:
-; ecx = (x * BgrDataWidth) / ScreenWidth
+; edx:ecx = x * 2^32 * (BgrDataWidth-1) / (ScreenWidth-1)
-; 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] = BgrDataWidth-1, x-limit for overlapping of points
+; qword [esp+12] = y * 2^32 * (BgrDataHeight-1) / (ScreenHeight-1)
-; dword [esp+16] = end of bgr memory (defines y-limit for overlapping of points)
 ; dword [esp+20] = x
-; dword [esp+24] = (y * BgrDataHeight) mod ScreenHeight (used to fast recalculating of esi)
-; dword [esp+28] = y
+; dword [esp+24] = y
 ; precalculated constants:
-; dword [esp+32] = BgrDataHeight mod ScreenHeight
-; dword [esp+36] = BgrDataHeight div ScreenHeight
+; qword [esp+28] = 2^32*(BgrDataHeight-1)/(ScreenHeight-1)
-; dword [esp+40] = BgrDataWidth mod ScreenWidth
+; qword [esp+36] = 2^32*(BgrDataWidth-1)/(ScreenWidth-1)
-; dword [esp+44] = BgrDataWidth div ScreenWidth
 sdp3:
-        add     edx, [esp+40]
         cmp     [ebp+WinMapAddress], byte 1
         jnz     snbgp
         mov     al, [esi+2]
         shl     eax, 16
         mov     ax, [esi]
-        cmp     ecx, [esp+12]
+        test    ecx, ecx
-        jae     @f
-        cmp     edx, [ScreenWidth]
-        jb      @f
+        jz      @f
         mov     ebx, [esi+2]
         shr     ebx, 8
         call    overlapping_of_points
 @@:
-        mov     ebx, [esp+24]
-        add     ebx, [esp+32]
+        cmp     dword [esp+12], 0
-        cmp     ebx, [ScreenHeight]
-        jbe     @f
+        jz      .novert
         mov     ebx, [BgrDataWidth]
         lea     ebx, [ebx*3]
         add     ebx, esi
+        push    eax
-        cmp     ebx, [esp+16]
+        mov     al, [ebx+2]
+        shl     eax, 16
+        mov     ax, [ebx]
+        test    ecx, ecx
-        jae     @f
+        jz      .nohorz
-        mov     ebx, [ebx-1]
+        mov     ebx, [ebx+2]
         shr     ebx, 8
         call    overlapping_of_points
+.nohorz:
+        mov     ebx, eax
+        pop     eax
+        push    ecx
+        mov     ecx, [esp+4+12]
+        call    overlapping_of_points
+        pop     ecx
-@@:
+.novert:
         mov     [edi], ax
         shr     eax, 16
         mov     [edi+2], al
 snbgp:
         cmp     [ScreenBPP], byte 25
         mov     eax, [esp+20]
         add     eax, 1
         mov     [esp+20], eax
         cmp     eax, [draw_data+32+RECT.right]
         ja      sdp4
+        add     ecx, [esp+36]
+        mov     eax, edx
-        mov     eax, [esp+44]
+        adc     edx, [esp+40]
-        add     ecx, eax
+        sub     eax, edx
         lea     eax, [eax*3]
-        add     esi, eax
+        sub     esi, eax
-;        add     edx, [esp+40]
-        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+28]
+        mov     ebx, [esp+24]
         add     ebx, 1
-        mov     [esp+28], ebx
+        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
         jz      @f
         sub     edi, eax
 @@:
         add     edi, [BytesPerScanLine]
 ; restore ecx,edx; advance esi to next background line
+        mov     eax, [esp+28]
+        mov     ebx, [esp+32]
+        add     [esp+12], eax
+        mov     eax, [esp+16]
+        adc     [esp+16], ebx
         pop     esi edx ecx
         push    ecx edx
-        xor     ebx, ebx
-        mov     eax, [esp+24-4]
-        add     eax, [esp+32-4]
+        sub     eax, [esp+16-4]
-        cmp     eax, [ScreenHeight]
-        jbe     @f
-        sub     eax, [ScreenHeight]
-        mov     ebx, 1
-        sub     eax, ebx
-@@:
-        mov     [esp+24-4], eax
-        add     ebx, [esp+36-4]
-        lea     ebx, [ebx*3]
+        lea     eax, [eax*3]
-        imul    ebx, [BgrDataWidth]
+        imul    eax, [BgrDataWidth]
-        add     esi, ebx
+        sub     esi, eax
         push    esi
         mov     eax, [draw_data+32+RECT.left]
         mov     [esp+20], eax
         jmp     sdp3
 sdpdone:
-        add     esp, 48
+        add     esp, 44
         popad
         mov     [EGA_counter],1
         call    VGA_drawbackground
         ret
 overlapping_of_points:
-        push    ecx edx edi
+        push    ecx edx
+        mov     edx, eax
+        push    esi
-        mov     ecx, eax
+        shr     ecx, 24
-        mov     edx, ebx
+        mov     esi, ecx
-        movzx   eax, cl
+        mov     ecx, ebx
-        movzx   ebx, dl
-        add     eax, ebx
-        rcr     eax, 1
+        movzx   ebx, dl
-        movzx   edi, ax
+        movzx   eax, cl
-        movzx   eax, ch
+        sub     eax, ebx
         movzx   ebx, dh
-        add     eax, ebx
-        rcr     eax, 1
-        ror     edi, 8
+        imul    eax, esi
-        add     edi, eax
-        shr     ecx, 8
-        shr     edx, 8
+        add     dl, ah
+        movzx   eax, ch
+        sub     eax, ebx
+        imul    eax, esi
+        add     dh, ah
+        ror     ecx, 16
+        ror     edx, 16
-        movzx   eax, ch
+        movzx   eax, cl
-        movzx   ebx, dh
+        movzx   ebx, dl
-        add     eax, ebx
+        sub     eax, ebx
-        rcr     eax, 1
+        imul    eax, esi
+        pop     esi
-        ror     edi, 8
+        add     dl, ah
+        mov     eax, edx
-        add     eax, edi
+        pop     edx
         ror     eax, 16
-        pop     edi edx ecx
+        pop     ecx

Subversion Repositories Kolibri OS

(root)/kernel/trunk/video/vesa20.inc – Rev 536 → 546