// F O N T W I D T H S -- publicly distributed file. (PREPRESS) // catalog number ??? //EncodeFace(weight,slope,expansion) => 8-bit face code. // An entry that is omitted or made zero is defaulted. // Arguments are upper case letters (e.g. M R R) //DecodeFace(face,lvweight,lvslope,lvexpansion) // Takes 8-bit face code and returns the three descriptive // letters. //LookupFontName(s,name,face,size,rotation,bufx,bufy,boundbox // [,bufferlength,lvp]) // Looks up the font named by name(string),face(encoded as above), // size(<0 =>microns, >0 => points), rotation(minutes). Returns // true if match exists, false otherwise. "s" is a stream // with FONTS.WIDTHS open on it. "bufx" and "bufy" will be filled // with x and y widths respectively (indexed by char code). // "boundbox" is a 4-word vector to receive the bounding box // (rotations of bounding box are not performed!) // "bufferlength" is the length of the buffer (256 if omitted). // "lvp" is filled @ with family code (may be omitted) //CalculateWidths(best,s,siz,rot,boundbox,bufx,bufy,bufl) // If you have a file you want to read by hand, use this proc. // best is an IX entry to get widths from; s is the file; rot // is the rotation you desire; boundbox is a vec 4 that will be // filled with the bounding box; bufx and bufy are as for // LookupFontName //MulDiv(a,b,c) => a*b/c // Multiply and scale. All arguments positive 16-bit numbers. // Maintains maximum precision. //SignedMulDiv(a,b,c) // Same as MulDiv, but will handle signed numbers. //Cos(theta,lvsign,lvmag) // Computes the cosine of the angle "theta" (in minutes) and // returns sign (0 if positive, -1 if negative) and magnitude // (0 to #177777) //get "ix.dfs" THE FOLLOWING IS A COPY IX.DFS // P R E P R E S S D E F I N I T I O N S // // I N D E X Definitions structure IXH: [ Type bit 4 Length bit 12 ] structure IXN: [ //For a name @IXH Code word Name word contd word 9 ] structure IX: [ //For splines, characters @IXH //Header [ fam byte // Family number face byte // Face code ] = famface word bc byte // First char number ec byte // and last siz word // Font size (10 micron units) rotation word // Rotation (anti clockwise) sa word 2 //Starting address of data part len word 2 //Length of data part //Width type ends here //Spline type ends here resolutionx word // 10*(number of bits/inch) resolutiony word // ditto ] manifest [ //IXH types IXTypeEnd=0 IXTypeName=1 IXTypeSplines=2 IXTypeChars=3 IXTypeWidths=4 //IXH lengths IXLEnd=1 IXLName=size IXN/16 IXLSplines=9 IXLChars=11 IXLWidths=9 IXLMax=11 ] // W I D T H segment definitions structure WTB: [ //Width Table Block XL word //X offset YB word //Y offset XW word // width YH word // height XWidthFixed bit YWidthFixed bit spare bit 14 ] // S P L I N E segment definitions structure SplineWidth: [ //Block describing spline widths WX word 2 //X width -- FP WY word 2 //Y width -- FP XL word 2 //X left -- FP YB word 2 //Y bottom -- FP XR word 2 //X right -- FP YT word 2 //Y top -- FP ] manifest SplineWidthsize=size SplineWidth/16 manifest [ //Codes in the height entry for a char that indicate something else HNonExCode=-1 HSplineCode=-2 //DL Types (for Spline File) DSplineFontMoveTo=1 DSplineFontDrawTo=2 DSplineFontDrawCurve=3 DSplineFontNewObject=-1 DSplineFontEndObjects=-2 ] // C H A R segment definitions (scan-converted chars) structure CharWidth: [ //Block describing char widths WX word 2 //X width -- DP WY word 2 //Y width -- DP XL word //X left (offset) integer YB word //Y bottom (offset) integer W word //Width (integer) H word //Height (integer) or special code ] manifest CharWidthsize=size CharWidth/16 structure FHEAD: [ //Font header, scan converted hw bit 6 //Height in words ns bit 10 //width in scan lines ] //Misc. structure Convert: [ Monotone word //True if input to conversion is monotone SplineOk word //True if output can be spline (too big) BBGood word //True if bounding box will be correct PressFontPart word //True if scan converting a press font part Len word // (if so, this is the length) ] manifest [ gotname=1 gotface=2 gotsize=4 gotrotation=8 gotincline=16 gotresolution=32 gotrecord=64 gotfactors=128 ] //END OF IX.DFS // outgoing procedures external [ EncodeFace LookupFontName CalculateWidths DecodeFace GenLookup MulDiv SignedMulDiv Cos ] // outgoing statics //external // [ // ] //static // [ // ] // incoming procedures external [ MoveBlock; SetBlock;Zero Gets ReadBlock Resets PositionPage PositionPtr ] // incoming statics //external // [ // ] // internal statics //static // [ // ] // File-wide structure and manifest declarations. structure STR: [ byt↑0,255 byte ] // Procedures let EncodeFace(weight,slope,expansion; numargs n) = valof [ for i=2 to n by -1 do (lv weight)!i=0 let w=(selecton weight into [ case 0: case $M: case $m: 0 case $B: case $b: 2 case $L: case $l: 4 default: -100 ]) + (selecton slope into [ case 0: case $R: case $r: 0 case $I: case $i: 1 default: -100 ]) + (selecton expansion into [ case 0: case $R: case $r: 0 case $C: case $c: 6 case $E: case $e: 12 default: -100 ]) if w ls 0 then resultis -1 resultis w ] and DecodeFace(face,w,s,e) be [ @s=(table [ $R; $I ])!(face&1) face=face rshift 1 @w=(table [ $M; $B; $L ])!(face rem 3) face=face/3 @e=(table [ $R; $C; $E ])!(face rem 3) ] and LookupFontName(s,famstr,face,siz,rot,bufx,bufy,boundbox,bufl,lvp; numargs na) = valof [ siz=(siz ls 0)? -siz,MulDiv(siz,635,18) //points to microns if na eq 8 then bufl=256 Resets(s) let p=vec IXLMax [ fwReadIX(s,p) //Read an IX entry if p>>IXH.Type eq IXTypeEnd then resultis false if p>>IXH.Type eq IXTypeName then [ let fnd=true let str=lv p>>IXN.Name for i=0 to str>>STR.byt↑0 do if ((str>>STR.byt↑i xor famstr>>STR.byt↑i)&(not #40)) ne 0 then fnd=false if fnd then break ] ] repeat let fam=p>>IXN.Code if na eq 10 then @lvp=fam let found=false let best=vec IXLMax [ fwReadIX(s,p) if p>>IXH.Type eq IXTypeEnd then break if p>>IXH.Type eq IXTypeWidths then [ //first fix the "off by one" possibility on sizes let newSiz=p>>IX.siz if ((newSiz-siz) eq 1) % ((newSiz-siz) eq -1) then newSiz=siz if p>>IX.fam eq fam & p>>IX.face eq face & ((newSiz eq siz & p>>IX.rotation eq rot) % (p>>IX.siz eq 0)) then [ if found eq false % p>>IX.siz ne 0 then MoveBlock(best,p,IXLMax) found=true ] ] //end of if IXTypeWidths ] repeat unless found then resultis false CalculateWidths(best,s,siz,rot,boundbox,bufx,bufy,bufl) resultis true ] and CalculateWidths(best,s,siz,rot,boundbox,bufx,bufy,bufl) be [ SetBlock(bufx,-1,bufl) SetBlock(bufy,-1,bufl) //Position s to read width table let p=lv best>>IX.sa //DP address of font part. PositionPage(s,(p!0 lshift 8)+(p!1 rshift 8)+1) PositionPtr(s,((p!1Ź) lshift 1)) let wt=vec size WTB/16 ReadBlock(s,wt,(size WTB/16)) MoveBlock(boundbox,wt,4) //Extract the bounding box info let bc=best>>IX.bc let ec=best>>IX.ec if bufl ls bc then return // yes but... let ecb=(ec ge bufl)? bufl,ec //Now read either one word or a number of words for the widths. for i=0 to 1 do [ let bufp=(lv bufx)!i+bc test ((i eq 0)? wt>>WTB.XWidthFixed,wt>>WTB.YWidthFixed) ifso [ let v=Gets(s) SetBlock(bufp,v,ecb-bc+1) ] ifnot [ ReadBlock(s,bufp,ecb-bc+1) ] ] //Now do scaling if needed. if best>>IX.siz ne 0 then return for i=bc to ecb do if bufx!i ne #100000 then [ bufx!i=MulDiv(bufx!i,siz,1000) bufy!i=MulDiv(bufy!i,siz,1000) ] for i=0 to 3 do boundbox!i=SignedMulDiv(boundbox!i,siz,1000) //And rotation if needed. if rot eq 0 then return let cm,cs,sm,ss=nil,nil,nil,nil Cos(rot,lv cs,lv cm) //Get cosine Cos(rot-90*60,lv ss,lv sm) //and sine for i=bc to ecb do if bufx!i ne #100000 then [ let t=MulDiv(bufx!i,cm,#177777) if cs then t=-t let s=MulDiv(bufy!i,sm,#177777) unless ss then s=-s let x=t+s t=MulDiv(bufy!i,cm,#177777) if cs then t=-t s=MulDiv(bufx!i,sm,#177777) if ss then s=-s bufx!i=x bufy!i=t+s ] ] and fwReadIX(s,p) be [ let a=Gets(s) //Type word. p!0=a let l=p>>IXH.Length if l then ReadBlock(s,p+1,l-1) ] and MulDiv(a,b,c) = valof [ // Returns a*b/c using unsigned arithmetic. MulDiv=table [ #55001 // STA 3,1,2 #155000 // MOV 2,3 save stack pointer #111000 // MOV 0,2 a #21403 // LDA 0,3,3 #101220 // MOVZR 0,0 c/2 #61020 // MUL #31403 // LDA 2,3,3 c #61021 // DIV #101010 // MOV# 0,0 #121000 // MOV 1,0 #171000 // MOV 3,2 #35001 // LDA 3,1,2 #1401 // JMP 1,3 ] resultis MulDiv(a,b,c) ] and SignedMulDiv(a,b,c) = valof [ let sgn=a xor b xor c //Sign bit let abs(x)=(x ge 0? x,-x) let res=MulDiv(abs(a),abs(b),abs(c)) resultis (sgn ls 0? -res,res) ] and Cos(theta,lvsign,lvmag) be [ //Calculate the cosine of the given angle, and return the // magnitude as a fraction of #177777 (largest number) // Also return sign (0 if positive, -1 if negative) if theta ls 0 then theta=-theta @lvsign=-(((theta+90*60)/(180*60))&1) let d=theta rem 90*60 if ((theta/(90*60))&1) ne 0 then d=90*60-d let min=d rem 60 //Minutes part d=d/60 //Degrees part //Now d in range 0-90 degrees let retrievecos(d,min) =valof [ //0 le d le 45 let cosar=table [ #177777; #177765; #177727; #177645; #177537; #177405; #177227; #177026; #176601; #176330; #176033; #175512; #175146; #174557; #174144; #173505; #173024; #172317; #171567; #171014; #170216; #167376; #166532; #165645; #164735; #164002; #163026; #162030; #161007; #157746; #156662; #155556; #154430; #153262; #152072; #150663; #147432; #146162; #144672; #143362; #142032; #140463; #137075; #135471; #134045; #132405; #130743; //46 degrees because of interpolation ] let a=cosar!d //First answer if min ne 0 then //Must interpolate [ let b=cosar!(d+1) a=a-MulDiv(a-b,min,60) //Careful about signs ] resultis a ] test d gr 45 then [ //Use half-angle formulae if (d&1) ne 0 then min=min+60 //Divide angle by 2 let a=retrievecos(d rshift 1,min rshift 1) a=MulDiv(a,a,#177777) // cos↑2(theta/2) a=a-#100000 // cos↑2 -1/2 @lvmag=a lshift 1 //2 cos↑2 -1 ] or @lvmag=retrievecos(d,min) ]