XDEF _interpret ; Bitmap-to-Ascii function XDEF _CopyFont ; Copies a font and aligns it to 16 bit. XREF _CharData ; Font data XREF _SrcData XREF _CharLoc XREF _CharKern XREF _Modulo XREF _FontWidth XREF _FontHeight XREF _Underscore XREF _TrueUnderscore XREF _LoChar XREF _HiChar XREF _IFlags XDEF _myActivateWindow SECTION CODE USC equ 1 ; Interpreted char was underscored PUSC equ 2 ; Prevoius char was underscored PUS equ 4 ; Pending underscored space CHEIGHT equ 24 ; Max height of unpacked character _interpret: link a5,#0 movem.l d1-d6/a1,-(sp) ; Free a couple of registers move.l 8(a5),a1 ; Bitmap move.w (a1),d2 ; First row moveq #0,d4 ; Code move.b _LoChar,d4 ; First char move.w _FontWidth,d0 asl.w #1,d0 ; Times two for words lea MaskTable,a0 move.w 0(a0,d0.w),d3 ; d3 := mask move.l _CharData,a0 ; Char image data bclr.b #PUS,_IFlags ; No pending-underscored-space .lp1 cmpi.b #31,d4 ; Into printable characters yet? bhi .Search ; If yes, go and start searching addq #1,d4 ; Move to next char adda.l #CHEIGHT*2,a0 ; Increment bitmap ptr also bra .lp1 ; Back to check again .Search cmp.w (a0),d2 ; Compare first word bne .tryinverted ; Not this one bclr.b #USC,_IFlags ; Assume not underscored moveq #1,d5 ; current word moveq #0,d6 ; Modulo .morerows addq #2,d6 ; Add modulo - next bit row in image data move.w 0(a0,d6.w),d1 ; Character row cmp.w 0(a1,d6.w),d1 beq .stdmatch ; Rows matched cmp.w _Underscore,d5 ; Could it be the underscore line? bne .tryinverted ; Nope tst.b _TrueUnderscore ; Use true underscore? beq .uscmatch ; No. Let's hope it's okay moveq #0,d1 ; 00000000 move.w 0(a0,d6.w),d0 ; 00110000 or.w d0,d1 ; 00110000 rol.l #2,d1 ; 0011000000 or.w d0,d1 ; 0011110000 ror.l #1,d1 ; X01111000 eor.w d3,d1 ; 10000111 or.w d0,d1 ; 10110111 move.w 0(a1,d6.w),d0 eor.w d0,d1 ; Zero if equal ; But, let's skip the last bit since it ; may be affected by the next character lsr.w #1,d1 ; Shift one step right and.w d3,d1 ; Mask out last bit bne .tryinverted .uscmatch bset.b #USC,_IFlags ; Set underscored flag .stdmatch addq #1,d5 ; Next row in bitmap cmp.w _FontHeight,d5 ; Are we done? bne .morerows ; Not yet cmp.b #' ',d4 ; Space bne .notuspace ; Space. Check for underscore btst.b #USC,_IFlags ; Underscored char? beq .notuspace ; Nope, everything ok ; Underscored space. Check if previous char was underscored btst.b #PUSC,_IFlags ; Previous char underscored? bne .okuspace ; Yep, ok underscored space ; Previous char not underscored. Set pending-underscored-space flag ; and go on to check if the normal underscore char matches bset.b #PUS,_IFlags bra .tryinverted .notuspace .okuspace bclr.b #PUSC,_IFlags ; Clear previous-underscored btst.b #USC,_IFlags ; Underscored char? beq .interpreted ; Nope bset.b #PUSC,_IFlags ; Set previous-underscored bra .interpreted ; Got it .tryinverted move.w (a0),d1 ; Copy first row eor.w d3,d1 ; and invert the bits cmp.w d2,d1 ; Compare inverted rows bne .trybold ; No match moveq #1,d5 ; current row moveq #0,d6 ; Modulo .moreinverted addq #2,d6 move.w 0(a0,d6.w),d1 ; Character row eor.w d3,d1 ; and invert the bits cmp.w 0(a1,d6.w),d1 bne .trybold ; Rows didn't match addq #1,d5 ; Next row in bitmap cmp.w _FontHeight,d5 ; Are we done? bne .moreinverted ; Not yet bra .interpreted ; Got it .trybold move.w (a0),d1 ; Copy first row lsr.w #1,d1 ; Shift one step left or.w (a0),d1 ; Make bold and.w d3,d1 ; and mask out unwanted bits cmp.w d2,d1 ; Compare bold rows bne .trynext ; No match moveq #1,d5 ; current row moveq #0,d6 ; Modulo .morebold addq #2,d6 move.w 0(a0,d6.w),d1 ; Character row lsr.w #1,d1 ; Shift one step left or.w 0(a0,d6.w),d1 ; Make bold and.w d3,d1 ; and mask out unwanted bits cmp.w 0(a1,d6.w),d1 bne .trynext ; Rows didn't match addq #1,d5 ; Next row in bitmap cmp.w _FontHeight,d5 ; Are we done? bne .morebold ; Not yet bra .interpreted ; Got it .trynext adda.l #CHEIGHT*2,a0 ; Try next character, 32 bytes/char cmp.b _HiChar,d4 ; Tried all chars? beq .nomore ; No more to try addq #1,d4 ; Next char bra .Search .nomore move.l #0,d4 ; Not found btst.b #PUS,_IFlags ; Hey, perhaps it was an underscored space? beq .interpreted ; Nope, return not-found move.l #' ',d4 .interpreted move.l d4,d0 movem.l (sp)+,d1-d6/a1 unlk a5 rts _CopyFont: movem.l d2-d6/a2/a3/a5,-(sp) ; Free a couple of registers moveq #0,d0 moveq #0,d6 ; Don't shift if no kerning data move.l _CharData,a2 ; a2 := Destination area move.l _CharLoc,a3 move.l _CharKern,a5 move.b _LoChar,d5 move.w _Modulo,d3 .NextChar move.w (a3)+,d0 ; Get char location move.w d0,d1 and.w #15,d1 ; Shift amount eori.b #15,d1 ; Negate shift value addq.b #1,d1 ; d1 := Shift Amount cmpa.l #0,a5 ; Check for kerning data beq .nokern ; No kerning to adjust for move.w (a5)+,d6 ; Kerning .nokern move.l _SrcData,a0 lsr.w #3,d0 ; Byte offset bclr #0,d0 ; But we deal in words adda.w d0,a0 ; a0 := chardata move.w (a3)+,d0 ; Get char width asl.w #1,d0 ; Times two for words lea MaskTable,a1 move.w 0(a1,d0.w),d2 ; d2 := mask moveq #0,d4 move.w _FontHeight,d4 move.l a2,a1 ; a1 := Destination area adda.w #CHEIGHT*2,a2 ; a2 to next dest area bra .loop .copyrow move.l (a0),d0 ; Get character row adda.w d3,a0 ; Add modulo -- To next row lsr.l d1,d0 ; Shift data to bit 0 alignment and.w d2,d0 ; Mask out unwanted bits lsr.w d6,d0 ; Shift according to kerning move.w d0,(a1)+ ; Save row .loop dbra d4,.copyrow ; Do all rows cmp.b _HiChar,d5 ; Finished? beq .copydone ; Yes addq #1,d5 ; Next char bra .NextChar ; Nope -- do next. .copydone movem.l (sp)+,d2-d6/a2/a3/a5 rts MaskTable dc.w $0000 dc.w $8000 dc.w $c000 dc.w $e000 dc.w $f000 dc.w $f800 dc.w $fc00 dc.w $fe00 dc.w $ff00 dc.w $ff80 dc.w $ffc0 dc.w $ffe0 dc.w $fff0 dc.w $fff8 dc.w $fffc dc.w $fffe dc.w $ffff _myActivateWindow: rts END