NodeStyleSpacesImpl.mesa
Copyright © 1985, 1986 by Xerox Corporation. All rights reserved.
Michael Plass, May 16, 1984 5:31:11 pm PDT
Rick Beach, March 23, 1985 5:20:39 pm PST
Russ Atkinson (RRA) June 20, 1985 2:10:21 am PDT
Doug Wyatt, September 2, 1986 1:16:35 pm PDT
DIRECTORY
Atom USING [GetPName],
Basics USING [bytesPerWord, LongNumber],
FS USING [Error, StreamOpen, StreamOptions],
ImagerFont USING [Font, Width],
IO USING [Close, Error, SetIndex, STREAM, UnsafeGetBlock],
MessageWindow USING [Append, Blink],
NodeStyle USING [FontFace, GetFontFamily, GetFontFace, GetFontSize, GetReal, Style],
NodeStyleFont USING [FontFromStyleParams],
Rope USING [Cat, Concat, ROPE];
NodeStyleSpacesImpl: CEDAR PROGRAM
IMPORTS Atom, FS, ImagerFont, IO, MessageWindow, NodeStyle, NodeStyleFont, Rope
EXPORTS NodeStyle
~ BEGIN
ROPE: TYPE ~ Rope.ROPE;
Space width attributes (exported to NodeStyle)
GetScreenSpaceWidth: PUBLIC PROC[style: NodeStyle.Style] RETURNS[REAL] ~ {
font: ImagerFont.Font ← style.font;
IF font = NIL THEN font ← NodeStyleFont.FontFromStyleParams[prefix: style.name[fontPrefix], family: style.name[fontFamily], face: style.fontFace, size: NodeStyle.GetReal[style, fontSize], alphabets: style.fontAlphabets];
RETURN[ImagerFont.Width[font, [set: 0, code: 40B]].x];
};
GetPrintSpaceWidth: PUBLIC PROC[style: NodeStyle.Style] RETURNS[width: REAL] ~ {
family: ROPE ~ Atom.GetPName[NodeStyle.GetFontFamily[style]];
face: NodeStyle.FontFace ~ NodeStyle.GetFontFace[style];
size: REAL ~ NodeStyle.GetFontSize[style];
fontName: ROPE ~ family.Concat[SELECT face FROM
Regular => "", Bold => "B", Italic => "I", BoldItalic => "BI", ENDCASE => ERROR];
tfmName: ROPE ~ Rope.Cat["///Fonts/FontMetrics/", fontName, ".tfm"];
stream: IO.STREAMNIL;
oops: BOOLFALSE;
binaryStreamOptions: FS.StreamOptions ~ [tiogaRead: FALSE, commitAndReopenTransOnFlush: TRUE, truncatePagesOnClose: TRUE, finishTransOnClose: TRUE, closeFSOpenFileOnClose: TRUE];
Protest: PROC [why: ROPE] = {
MessageWindow.Append[why, TRUE];
MessageWindow.Append[" (using 1/2 font size for space size)", FALSE];
MessageWindow.Blink[];
};
width ← size/2; -- default in case of disaster;
stream ← FS.StreamOpen[fileName: tfmName, accessOptions: $read, streamOptions: binaryStreamOptions
! FS.Error => {
Protest[error.explanation];
CONTINUE
}];
IF stream#NIL THEN TRUSTED {
dir: Directory;
dirAddr: LONG POINTER ← @dir;
param: Param;
paramAddr: LONG POINTER ← @param;
[] ← stream.UnsafeGetBlock[
[base: dirAddr, startIndex: 0, count: SIZE[Directory]*Basics.bytesPerWord]
! IO.Error => {oops ← TRUE; CONTINUE}
];
oops ← oops OR NOT ValidDirectory[dir];
IF NOT oops THEN stream.SetIndex[ParamStart[dir]*SIZE[Word]*Basics.bytesPerWord
! IO.Error => {oops ← TRUE; CONTINUE}
];
IF NOT oops THEN [] ← stream.UnsafeGetBlock[
[base: paramAddr, startIndex: 0, count: SIZE[Param]*Basics.bytesPerWord]
! IO.Error => {oops ← TRUE; CONTINUE}
];
IF oops
THEN Protest[Rope.Concat[tfmName, " is invalid"]]
ELSE {
unscaledSpaceWidth: REAL ← Long[param[spaceWidth]]/realTwoToTheTwentieth;
width ← unscaledSpaceWidth*size;
};
stream.Close[! IO.Error => CONTINUE];
};
};
twoToTheTenth: INT ~ 2*2*2*2*2 * 2*2*2*2*2;
twoToTheTwentieth: INT ~ twoToTheTenth*twoToTheTenth;
realTwoToTheTwentieth: REAL ~ twoToTheTwentieth;
Copied from TFM defs
Word: TYPE ~ MACHINE DEPENDENT RECORD [hiHalf, lowHalf: CARDINAL];
note a Word is 32 bits long, and in BigEndian order.
Fixed: TYPE ~ MACHINE DEPENDENT RECORD [ValueTimesTwoToTheTwentieth: Word];
FixedArray: TYPE ~ MACHINE DEPENDENT RECORD [
entry(0): PACKED SEQUENCE COMPUTED CARDINAL OF Fixed];
Long: PROC [w: Word] RETURNS [INT] ~ INLINE {
t: Basics.LongNumber ← [num[lowbits: w.lowHalf, highbits: w.hiHalf]];
RETURN[t.li]
};
Directory: TYPE ~ MACHINE DEPENDENT RECORD [
lf: CARDINAL, -- length of entire file in Words
lh: CARDINAL, -- length of header data
bc: CARDINAL, -- first character code in font
ec: CARDINAL, -- last character code in font
nw: CARDINAL, -- number of Words in width table
nh: CARDINAL, -- number of Words in height table
nd: CARDINAL, -- number of Words in depth table
ni: CARDINAL, -- number of Words in italic correction table
nl: CARDINAL, -- number of Words of lig/kern program
nk: CARDINAL, -- number of Words in kern table
ne: CARDINAL, -- number of Words in extensible character table
np: CARDINAL -- number of font parameters
];
ValidDirectory: PROC [h: Directory] RETURNS [BOOLEAN] ~ {
OPEN h;
RETURN [lh<=24 -- Allow headers to grow a bit -- AND
ec>=bc AND ec<256 AND
nw <= 256 AND
nh <= 16 AND
nd <= 16 AND
ni <= 64 AND
nl <= 256 AND
nk <= 256 AND
ne <= 256 AND
np <= 24 AND
lf = 6 + lh + (ec-bc+1) + nw + nh + nd + ni + nl + nk + ne + np]
};
ParamStart: PROC [h: Directory] RETURNS [CARDINAL] ~ INLINE {
OPEN h;
RETURN [6 + lh + (ec-bc+1) + nw + nh + nd + ni + nl + nk + ne]
};
Param: TYPE ~ PACKED ARRAY ParamIndex OF Fixed;
ParamIndex: TYPE ~ MACHINE DEPENDENT {-- see MetaFont manual, pages 98-100
slant(0), -- index for amount of italic slant (do not scale)
spaceWidth(1),
spaceStretch(2),
spaceShrink(3),
xHeight(4),
quad(5),
x0,x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,mathSyParamLen
};
END.