; BGIFONT.INC v1.0 beta
;
; Written in pure assembler by Ivushkin Andrey aka Willow
;
; Created: December 16, 2004
;
; Last changed: August 27, 2006
;
; Compile with FASM

; BGI constants
BGI_NODRAW   equ 0x10000
BGI_ITALIC   equ 0x20000
BGI_BOLD     equ 0x40000
BGI_HALEFT   equ 0x0
BGI_HARIGHT  equ 0x1000
BGI_HACENTER equ 0x2000
BGI_VABOTTOM equ 0x0
BGI_VATOP    equ 0x4000
BGI_VACENTER equ 0x8000

BGI_FREE     equ 0x80000000
BGI_HAMASK   equ 0x3000
BGI_VAMASK   equ 0xc000

; Freetext structure
struc BGIfree FontName,XY,Angle,ScaleX,ScaleY,StrPtr,StrLen,Color,Align
{
    dd FontName ;0
    dd XY	    ;4
    dd Angle	;8
    dd ScaleX	;12
    dd ScaleY	;16
    dd StrPtr	;20
    dd StrLen	;24
    dd Color	;28
    dd Align	;32
}

macro BGIfont_GetID
{
    call _BGIfont_GetID
}

macro BGIfont_Prepare
{
    call _BGIfont_Prepare
}

macro BGIfont_Freetext
{
    call _BGIfont_Freetext
}

macro BGIfont_Outtext
{
    call _BGIfont_Outtext
}

macro _FI name,_size
{
    db name
if BGI_LEVEL eq KERNEL
    dw _size
end if
}

BGIfont_get2head:
    shr  ecx,28 ; font #
    sub  ecx,4
    jb	 .exit2	; invalid #
    mov  edi,[BGIfont_Ptr]
    inc  edi
    cmp  cl,[edi-1]
    jae  .exit2 ; # too large
    jecxz .ex
  .fnext:
    mov  edi,[edi+16]
    loop .fnext
    jmp  .ex
  .exit2:
    xor  edi,edi
  .ex:
    ret

macro dps2 _str
{
	if LOAD_MSG eq 1
	dps _str
	end if
}

macro dph2 num,x,y
{
if  BGI_LEVEL eq KERNEL
    pusha
    mov  eax,0x00080100
    mov  ebx,num
    mov  ecx,x shl 16+y
    mov  edx,0xFF0000
    call display_number
    popa
end if
}

_BGIfont_GetID:
; in:  edx-font name;
; out: eax-fontID, edi->BGIrec
    push ecx edi
    mov  edi,[BGIfont_Ptr]
    movzx ecx,byte[edi] ; ecx-font count
    mov  eax,ecx
    inc  edi ; edi->FontName
    jecxz .ex
  .fnext:
    cmp  edx,[edi]
    jne  .floop
    sub  eax,ecx
    add  eax,4
    shl  eax,28
    jmp  .ex
  .floop:
    mov  edi,[edi+16]
    loop .fnext
  .num0:
    xor  eax,eax
  .ex:
    pop  edi ecx
    ret

_BGIfont_Prepare:
; in:  edx-font name, edi->pointer to load fonts (fonts_count)
; out: eax-ID of new font loaded; eax=0 error
    cmp  [BGIfont_Ptr],0
    jne  .already
    mov  [BGIfont_Ptr],edi
  .already:
    pusha
    mov  edi,[BGIfont_Ptr]
    movzx ecx,byte[edi] ; ecx-font count
    mov  eax,ecx
    inc  edi ; edi->FontName
    jecxz .fload
  .fnext:
    cmp  edx,[edi]
    jne  .loop
    sub  eax,ecx
    inc  eax
    jmp  .cr_id
  .loop:
    mov  edi,[edi+16]
    loop .fnext
  .fload:
    mov  dword[.font],edx ; filename
    mov  esi,edi     ; esi->FontName
    mov  [.dest],edi ; ptr to load font
    ;    mov     eax, 70
    ;    mov     ebx, .fontattr
    ;    mcall
    ;    test    eax, eax
    ;    ;jnz     .fail
    ;    dps2    '1'
    ;    mov     eax, [.fileattr+32]
    ;mov  [.fsize], litt_end-litt_file
    ;mov  ebx,.fontinfo
    ;mov  eax,70
    ;mcall	     ; ebx - file size
    mov ebx, litt_end-litt_file
    mov edi, litt_file
	mov  [.dest],litt_file ; ptr to load font

    cmp  dword[edi],0x08084b50 ; 'PK',8,8
    jne  .fail
    dps2 '2'
    inc  edi
    mov  eax,26 ; #EOF
    mov  ecx,253
    cld
    repne scasb  ; skip Copyright
    test ecx,ecx
    jz	 .fail
    dps2  '3'
    cmp  edx,[edi+2] ; FontName
    jne  .fail
    dps2  '4'
    movzx ecx,word[edi] ; HeaderSize
    sub  ebx,ecx  ; Filesize-Headersize
    movzx eax,word[edi+6] ; FontSize
    cmp  eax,ebx
    jb	 .fail	  ; file truncated
    add  ecx,[.dest]
    dps2  '5'
    cmp  byte[ecx],'+'	; ParPrefix
    jne  .fail
; font is valid, let's fill parameter table
    dps2  '>'
    mov  [esi],edx ; FontName
    mov  edx,eax
    add  eax,ecx
    mov  [esi+16],eax ; Font EOF
    movzx eax,word[ecx+5]
    add  eax,ecx
    mov  [esi+12],eax
    lea  edi,[esi+4]  ; edi->CharsCount
    lea  esi,[ecx+1] ; esi->ParPrefix+1
    xor  eax,eax
    lodsw
    stosb  ; CharsCount
    inc  esi
    movsb  ; FirstChar
    add  esi,3
    lodsw
    stosb  ; UpperMargin
    movsb  ; LowerMargin
    add  esi,5 ; esi->offsets
    mov  eax,[esi]
    push edi ; edi->Widths
; prepare moving data
    add  edi,12 ; edi->offsets
    lea  ecx,[edx-16]
    rep  movsb
    pop  edi ; edi->Widths
    mov  [edi+8],esi ; EOF
;    mov  eax,[edi]
    movzx ecx,byte[edi-4] ; CharsCount
    lea  eax,[edi+12+ecx*2] ; eax->widths
    stosd  ; edi->FirstData
    add  eax,ecx
    stosd  ; edi->EOF
    mov  eax,[esp] ; eax->fonts_count
    inc  byte[eax] ; increase font counter
    movzx eax,byte[eax]
  .cr_id:
    add  eax,0x3   ; create unique ID
    shl  eax,28    ; to easy use in color(ecx)
    jmp  .exit
  .fail:
    xor  eax,eax
  .exit:
    mov  [esp+28],eax
    popa
    ret

.fontinfo:
	dd 0
	dd 0
	dd 0
.fsize	dd 0
.dest	dd 0
.fontfullname:
	db BGIFONT_PATH
.font	db 'LITT.CHR',0

.fontattr:
        dd      5
        dd      0
        dd      0
        dd      0
        dd      .fileattr
        db      0
        dd      .fontfullname
.fileattr rd 40/4


BGIfont_Coo:
; y->word[txt.y1], x->word[txt.x1]
    fild [txt.y1] ;y
    fmul st0,st0; y*y
    fild [txt.x1] ;x
    fmul st0,st0; x*x
    faddp  ; x*x+y*y
    fsqrt  ; sqrt, angle
    fild [txt.y1];y
    fabs
    fild [txt.x1] ; x
    fabs
    fpatan ; arctg(y/x)
  .skip:
    cmp  [txt.x1],0
    jge  .xplus
    fchs
    fadd st0,st3
  .xplus:
    cmp  [txt.y1],0
    jge  .yplus
    fchs
  .yplus:
    fadd st0,st2
    fsincos
    fmul st0,st2
    fiadd [txt.x0]
    fistp [txt.x1] ; x=r*cos a
    fmulp ; y=r*sin a,angle
    fiadd [txt.y0]
    fistp [txt.y1]
    ret

_BGIfont_Freetext:
; in: ebx-BGIfree structure
; out: eax-new drawing coords
    mov  edx,[ebx]
    call _BGIfont_GetID
    test eax,eax
    jnz  .fexists
    ret
  .fexists:
    pusha
    fninit
    fldpi
    fld  [pi180]
    fimul dword[ebx+8]
    fst  [BGIangle]
    mov  esi,[ebx+28]
    and  esi,0xffffff
    add  esi,eax
    mov  eax,[ebx+32]
    and  [deform],0
    test eax,BGI_ITALIC
    jz	 .norm
    mov  [deform],dword 0.4
  .norm:
    mov  ebp,eax
    or	  ebp,BGI_FREE
    mov  eax,[ebx+12]
    mov  [Xscale],eax
    mov  eax,[ebx+16]
    mov  [Yscale],eax
    mov  ecx,[ebx+20]
    mov  edx,ebp
    and  edx,BGI_FREE+BGI_VAMASK+BGI_HAMASK
    add  edx,[ebx+24]
    mov  eax,[ebx+4]
    mov  ebx,esi
    add  ebx,0x6000000
    mov  [esp+4],edx
    mov  [esp+20],ecx
    jmp  txt

    pi180 dd 0.017453

_BGIfont_Outtext:
; in: ebx-[x][y], ecx-color, edx-string, esi-length
    pusha
    mov  ebp,esi
if ~ BGI_LEVEL eq KERNEL
    mov  eax,ebx
    mov  ebx,ecx
    mov  ecx,edx
    mov  edx,esi
end if
; in: eax-[x][y], ebx-color, ecx-string, edx-length
txt:
if  ~ BGI_LEVEL eq KERNEL
  if  BGI_WINDOW_CLIP eq 1
    pusha
    mov  eax,9
    mov  ebx,BGI_PRC_INFO
    mov  ecx,-1
    mcall
    popa
  end if
end if
    mov  [.y0],ax
    shr  eax,16
    mov  [.x0],ax
    mov  ecx,ebx ; color
    and  ebx,0xfffffff
    mov  [.color],ebx
    call BGIfont_get2head
    test edi,edi
    jz   .exit
    mov  ecx,[esp+4]; str length
    mov  esi,[esp+20]; str ptr
    movzx eax,byte[edi+5]
    push ecx
    and  ecx,0xff
    jnz  .lenok
    add  esp,4
    jmp  .ex2
  .lenok:
    pusha
    push dword[txt.y0]
    and  dword[txt.y0],0
    xor  edx,edx
    mov  ebx,[edi+8]
   .next:
    call txt.BGIfont_GetChar
    movzx eax,byte[ebx+eax]
    add  edx,eax
    loop .next
    mov  ecx,edx ; ecx - x size
    movzx dx,byte[edi+6]
    mov  [BGIheight],dx
    mov  ebx,[esp+36]
    and  ebx,BGI_HAMASK
    cmp  ebx,BGI_HARIGHT
    je   .nova
    ja   .subv
    xor  ecx,ecx
    jmp  .nova
  .subv:
    shr  cx,1
  .nova:
    mov  ebx,[esp+36]
    and  ebx,BGI_VAMASK
    cmp  ebx,BGI_VATOP
    je   .def
    ja   .subh
    xor  edx,edx
    jmp  .def
  .subh:
    shr  dx,1
  .def:
    call txt.BGIfont_Deform
    pop  dword[txt.y0]
    popa
    pop  ebx
    mov  ax,[txt.y1]
    sub  [txt.y0],ax
    mov  ax,[txt.x1]
    sub  [txt.x0],ax
    xor  eax,eax
    cld
.mloop:
    push [.y0]
    pop  [.y]
    push [.x0]
    pop  [.x]
    call .BGIfont_GetChar
    push esi
    lea  esi,[edi+20] ; offset
    movzx edx,word[esi+eax*2] ; ofs1
    add  edx,[edi+12]
    inc  eax
    cmp  al,[edi+4]
    je	 .eof
    movzx eax,word[esi+eax*2]; ofs2
    add   eax,[edi+12]
    jmp   .prc_vec
  .eof:
    mov  eax,[edi+16] ; ofs2=eof
  .prc_vec:  ; edx-vec cmd ifs, eax-cmd limit
    mov  [.vec_end],eax
    push ecx
  .vec_loop:
    mov  ax,word[edx]
    push edx
    mov  ecx,eax
    and  eax,0x8080 ; op
    and  ecx,0x7f ; xx
    mov  edx,[edx+1]
    and  edx,0x7f ; yy
    cmp  edx,63
    jbe  .positive
    sub  edx,128  ; yy-=128
  .positive:
    cmp  ecx,63
    jbe  .positive2
    sub  ecx,128  ; xx-=128
  .positive2:
    call .BGIfont_Deform
    cmp  eax,0x8080
    jne  .noline
    test ebp,BGI_NODRAW
    jnz  .noline
; draw vector
if ~ BGI_LEVEL eq KERNEL
    push eax
    mov  ebx,dword[.x1]
    mov  ecx,dword[.y1]
  if BGI_WINDOW_CLIP eq 1
    movzx eax,[.x]
    cmp  eax,dword[BGI_PRC_INFO+42]
    ja   .nobold
    movzx eax,[.y]
    cmp  eax,dword[BGI_PRC_INFO+46]
    ja  .nobold
    xor  eax,eax
    cmp  ax,bx
    jg   .nobold
    cmp  ax,cx
    jg   .nobold
  end if
    mov  edx,[.color]
; \begin{diamond}[18.08.2006]
; starting from K0530 kernel interprets flag 0x1000000 as
; negate existing pixels colors, disregarding passed color
; we do not want this
    and  edx, 0xFFFFFF
; \end{diamond}[18.08.2006]
    mov  eax,38
    mcall
    test ebp,BGI_BOLD
    jz	 .nobold
    test ebp,BGI_FREE
    jnz  .free5
  .free5:
    add  ebx,1 shl 16+1
    mcall
  .nobold:
    pop  eax
else
    pusha
    mov  eax,dword[.x1]
    mov  ebx,dword[.y1]
    mov  ecx,[.color]
;    call syscall_drawline
    test dword[esp+8],BGI_BOLD
    jz	 .nobold
    add  eax,1 shl 16+1
;    call syscall_drawline
  .nobold:
    popa
end if
  .noline:
    pop  edx
    test eax,eax
    je	 .eovecs  ; op=0
    push [.y1]
    pop  [.y]
    push [.x1]
    pop  [.x]
    add  edx,2
    cmp  edx,[.vec_end]
    jb	 .vec_loop
  .eovecs:
    pop  ecx esi
    push [.y]
    pop  [.y0]
    push [.x]
    pop  [.x0]
    loop .mloop1
    jmp  .exit
  .mloop1:
    jmp  .mloop
  .exit:
    mov  eax,dword[.y0]
    mov  [esp+28],eax
  .ex2:
    popa
    ret

.BGIfont_Deform:
    test ebp,BGI_FREE
    jnz  .free0
    movzx ebx,byte[.color+3] ;ebx=scale
    imul ecx,ebx
    add  ecx,2
    shr  ecx,2
    imul edx,ebx
    add  edx,2
    shr  edx,2
    neg  edx
    mov  [.x1],cx
    mov  [.y1],dx
    jmp  .add
  .free0:
    mov  [.x1],cx
    mov  [.y1],dx
    fild [.y1]
    fld  st0
    fmul [Yscale]
    fchs
    fistp [.y1]
    fmul [deform]
    fiadd [.x1]
    fmul [Xscale]
    fistp [.x1]
    cmp  [BGIangle],0
    je	 .add
    call BGIfont_Coo
    jmp  .eax
  .add:
    mov  cx,[.x0]
    add  [.x1],cx
    mov  cx,[.y0]
    add  [.y1],cx
  .eax:
    ret

.BGIfont_GetChar:
; in:  esi -> string; edi -> BGIrec
; out: esi -> next char; al - char obtained
    lodsb  ; al - char from str
    sub  al,[edi+5]
    jb	 .out
    cmp  al,[edi+4]
    jb	 .in
  .out:
    xor  al,al ; al - 1st symbol available
  .in:
    ret

.y0	 dw ?
.x0	 dw ?

.x1	 dw ?
.x	 dw ?
.y1	 dw ?
.y	 dw ?

.color	 dd ?
.vec_end dd ?
BGIfont_Ptr  dd 0
BGIheight dw ?
deform dd ?
BGIangle dd ?
Xscale  dd ?
Yscale  dd ?