struc BLITTER
{
   .dc.xmin    rd  1   ;   0
   .dc.ymin    rd  1   ;   4
   .dc.xmax    rd  1   ;   8
   .dc.ymax    rd  1   ;  12

   .sc:
   .sc.xmin    rd  1   ;  16
   .sc.ymin    rd  1   ;  20
   .sc.xmax    rd  1   ;  24
   .sc.ymax    rd  1   ;  28

   .dst_x      rd  1   ;  32
   .dst_y      rd  1   ;  36
   .src_x      rd  1   ;  40
   .src_y      rd  1   ;  44
   .w          rd  1   ;  48
   .h          rd  1   ;  52

   .bitmap     rd  1   ;  56
   .stride     rd  1   ;  60

}

virtual at 0
  BLITTER BLITTER
end virtual


align 4

__L1OutCode:
        push  ebx
        mov ebx, 8
        cmp edx, [eax]
        jl  .L2
        xor ebx, ebx
        cmp edx, [eax+8]
        setg  bl
        sal ebx, 2
.L2:
        cmp ecx, [eax+4]
        jge .L3
        or  ebx, 1
        jmp .L4

.L3:
        cmp ecx, [eax+12]
        jle .L4
        or  ebx, 2
.L4:
        mov eax, ebx
        pop ebx
        ret

align 4
block_clip:
        push  ebp
        push  edi
        push  esi
        push  ebx
        sub esp, 4

        mov ebx, eax
        mov [esp], edx
        mov ebp, ecx
        mov ecx, [ecx]
        mov edx, [edx]
        call  __L1OutCode

        mov esi, eax
        mov edx, [esp+28]
        mov ecx, [edx]
.L21:
        mov  eax, [esp+24]
        mov  edx, [eax]
        mov  eax, ebx
        call __L1OutCode

        mov  edi, eax
.L20:
        mov eax, edi
        and eax, esi
        jne .L9
        cmp esi, edi
        je  .L9
        test  esi, esi
        jne .L10
        test  edi, 1
        je  .L11
        mov eax, [ebx+4]
        jmp .L25
.L11:
        test  edi, 2
        je  .L13
        mov eax, [ebx+12]
.L25:
        mov edx, [esp+28]
        jmp .L22
.L13:
        test  edi, 4
        je  .L14
        mov eax, [ebx+8]
        jmp .L26
.L14:
        and  edi, 8
        je .L12
        mov  eax, [ebx]
.L26:
        mov  edx, [esp+24]
.L22:
        mov  [edx], eax
.L12:
        mov eax, [esp+28]
        mov ecx, [eax]
        jmp .L21
.L10:
        test  esi, 1
        je  .L16
        mov eax, [ebx+4]
        jmp .L23
.L16:
        test  esi, 2
        je  .L18
        mov eax, [ebx+12]
.L23:
        mov [ebp+0], eax
        jmp .L17
.L18:
        test  esi, 4
        je  .L19
        mov eax, [ebx+8]
        jmp .L24
.L19:
        and esi, 8
        je  .L17
        mov eax, [ebx]
.L24:
        mov edx, [esp]
        mov [edx], eax
.L17:
        mov ecx, [ebp+0]
        mov eax, [esp]
        mov edx, [eax]
        mov eax, ebx
        call  __L1OutCode
        mov esi, eax
        jmp .L20
.L9:
        add esp, 4
        pop ebx
        pop esi
        pop edi
        pop ebp
        ret

align 4
blit_clip:

.sx0   equ 36
.sy0   equ 32
.sx1   equ 28
.sy1   equ 24

.dx0   equ 20
.dy0   equ 16
.dx1   equ 12
.dy1   equ 8


        push  edi
        push  esi
        push  ebx
        sub esp, 40

        mov ebx, ecx
        mov edx, [ecx+BLITTER.src_x]
        mov [esp+.sx0], edx
        mov eax, [ecx+BLITTER.src_y]
        mov [esp+.sy0], eax
        add edx, [ecx+BLITTER.w]
        dec edx
        mov [esp+.sx1], edx
        add eax, [ecx+BLITTER.h]
        dec eax
        mov [esp+.sy1], eax

        lea ecx, [esp+.sy0]
        lea edx, [esp+.sx0]
        lea eax, [ebx+BLITTER.sc]
        lea esi, [esp+.sy1]

        mov [esp+4], esi
        lea esi, [esp+.sx1]
        mov [esp], esi
        call  block_clip

        mov esi, 1
        test  eax, eax
        jne .L28

        mov edi, [esp+.sx0]
        mov edx, [ebx+BLITTER.dst_x]
        add edx, edi
        sub edx, [ebx+BLITTER.src_x]
        mov [esp+.dx0], edx

        mov ecx, [esp+.sy0]
        mov eax, [ebx+BLITTER.dst_y]
        add eax, ecx
        sub eax, [ebx+BLITTER.src_y]
        mov [esp+.dy0], eax
        sub edx, edi
        add edx, [esp+.sx1]
        mov [esp+.dx1], edx

        sub eax, ecx
        add eax, [esp+.sy1]
        mov [esp+.dy1], eax

        lea ecx, [esp+.dy0]
        lea edx, [esp+.dx0]
        lea eax, [esp+.dy1]
        mov [esp+4], eax
        lea eax, [esp+.dx1]
        mov [esp], eax
        mov eax, ebx
        call  block_clip
        test  eax, eax
        jne .L28

        mov edx, [esp+.dx0]
        mov eax, [esp+.dx1]
        inc eax
        sub eax, edx
        mov [ebx+BLITTER.w], eax

        mov eax, [esp+.dy0]
        mov ecx, [esp+.dy1]
        inc ecx
        sub ecx, eax
        mov [ebx+BLITTER.h], ecx

        mov ecx, [ebx+BLITTER.src_x]
        add ecx, edx
        sub ecx, [ebx+BLITTER.dst_x]
        mov [ebx+BLITTER.src_x], ecx

        mov ecx, [ebx+BLITTER.src_y]
        add ecx, eax
        sub ecx, [ebx+BLITTER.dst_y]
        mov [ebx+BLITTER.src_y], ecx
        mov [ebx+BLITTER.dst_x], edx
        mov [ebx+BLITTER.dst_y], eax
        xor esi, esi
.L28:
        mov eax, esi
        add esp, 40
        pop ebx
        pop esi
        pop edi


purge .sx0
purge .sy0
purge .sx1
purge .sy1

purge .dx0
purge .dy0
purge .dx1
purge .dy1

        ret



align 4

blit_32:
        push ebp
        push edi
        push esi
        push ebx
        sub  esp, 72

        mov  eax, [TASK_BASE]
        mov  ebx, [eax-twdw + WDATA.box.width]
        mov  edx, [eax-twdw + WDATA.box.height]

        xor  eax, eax

        mov  [esp+BLITTER.dc.xmin], eax
        mov  [esp+BLITTER.dc.ymin], eax
        mov  [esp+BLITTER.dc.xmax], ebx
        mov  [esp+BLITTER.dc.ymax], edx

        mov  [esp+BLITTER.sc.xmin], eax
        mov  [esp+BLITTER.sc.ymin], eax
        mov  eax, [ecx+24]
        dec  eax
        mov  [esp+BLITTER.sc.xmax], eax
        mov  eax, [ecx+28]
        dec  eax
        mov  [esp+BLITTER.sc.ymax], eax

        mov  eax, [ecx]
        mov  [esp+BLITTER.dst_x], eax
        mov  eax, [ecx+4]
        mov  [esp+BLITTER.dst_y], eax

        mov  eax, [ecx+16]
        mov  [esp+BLITTER.src_x], eax
        mov  eax, [ecx+20]
        mov  [esp+BLITTER.src_y], eax
        mov  eax, [ecx+8]
        mov  [esp+BLITTER.w], eax
        mov  eax, [ecx+12]
        mov  [esp+BLITTER.h], eax


        mov  eax, [ecx+32]
        mov  [esp+56], eax
        mov  eax, [ecx+36]
        mov  [esp+60], eax

        mov  ecx, esp
        call blit_clip
        test eax, eax
        jne  .L57

        inc  [mouse_pause]
        call [_display.disable_mouse]

        mov  eax, [TASK_BASE]

        mov  ebx, [esp+BLITTER.dst_x]
        mov  ebp, [esp+BLITTER.dst_y]
        add  ebx, [eax-twdw + WDATA.box.left]
        add  ebp, [eax-twdw + WDATA.box.top]
        mov  edi, ebp

        imul edi, [_display.pitch]
        imul ebp, [_display.width]
        add  ebp, ebx
        add  ebp, [_WinMapAddress]

        mov  eax, [esp+BLITTER.src_y]
        imul eax, [esp+BLITTER.stride]
        mov  esi, [esp+BLITTER.src_x]
        lea  esi, [eax+esi*4]
        add  esi, [esp+BLITTER.bitmap]

        mov  ecx, [esp+BLITTER.h]
        mov  edx, [esp+BLITTER.w]

        test ecx, ecx       ;FIXME check clipping
        jz   .L57

        test edx, edx
        jz   .L57

        cmp [_display.bpp], 32
        jne .core_24

        lea edi, [edi+ebx*4]

        mov ebx, [CURRENT_TASK]

align 4
.outer32:
        xor ecx, ecx

align 4
.inner32:
        cmp [ebp+ecx], bl
        jne @F

        mov eax, [esi+ecx*4]
        mov [LFB_BASE+edi+ecx*4], eax
@@:
        inc ecx
        dec edx
        jnz .inner32

        add esi, [esp+BLITTER.stride]
        add edi, [_display.pitch]
        add ebp, [_display.width]

        mov edx, [esp+BLITTER.w]
        dec [esp+BLITTER.h]
        jnz .outer32

.done:
        dec  [mouse_pause]
        call [draw_pointer]
.L57:
        add  esp, 72
        pop  ebx
        pop  esi
        pop  edi
        pop  ebp
        ret

.core_24:
        lea ebx, [ebx+ebx*2]
        lea edi, [LFB_BASE+edi+ebx]
        mov ebx, [CURRENT_TASK]

align 4
.outer24:
        mov [esp+64], edi
        xor ecx, ecx

align 4
.inner24:
        cmp [ebp+ecx], bl
        jne @F

        mov eax, [esi+ecx*4]

        lea edi, [edi+ecx*2]
        mov [edi+ecx], ax
        shr eax, 16
        mov [edi+ecx+2], al
@@:
        mov edi, [esp+64]
        inc ecx
        dec edx
        jnz .inner24

        add esi, [esp+BLITTER.stride]
        add edi, [_display.pitch]
        add ebp, [_display.width]

        mov edx, [esp+BLITTER.w]
        dec [esp+BLITTER.h]
        jnz .outer24

        jmp .done