<<>>
    <<ImagerFDTypeface.mesa>>
        <<Copyright Ó 1989, 1991 by Xerox Corporation.  All rights reserved.>>
        <<Michael Plass, June 14, 1989 11:57:47 am PDT>>
        <<>>
    DIRECTORY
        BasicTime USING [GMT],
        ImagerBox USING [Extents],
        ImagerFont USING [CorrectionType],
        ImagerTransformation USING [Transformation],
        ImagerTypeface USING [Typeface],
        IO USING [STREAM],
        Prop USING [PropList],
        RefTab USING [Ref],
        Rope USING [ROPE],
        Vector2 USING [VEC];

    ImagerFDTypeface: CEDAR DEFINITIONS
    = BEGIN

        password: CARD32 = 19FD6A03H; -- the first four bytes of the file (big endian); low order byte is a version number.

        ROPE: TYPE = Rope.ROPE;
        VEC: TYPE = Vector2.VEC;
        Transformation: TYPE = ImagerTransformation.Transformation;

        Data: TYPE = REF DataRep;
        DataRep: TYPE = RECORD [
            fontExtents: ImagerBox.Extents,
            commonLeftExtents: RealSeq,
            commonRightExtents: RealSeq,
            commonDescents: RealSeq,
            commonAscents: RealSeq,
            commonEscapements: RealSeq,
            charToDeviceTransformations: TransformationSeq,
                <<NIL Transformation means resolution-independent>>
            typefaceCellSeq: TypefaceCellSeq,
            placementTransformations: TransformationSeq,
            overflowCharInfoSeq: OverflowCharInfoSeq,
            charInfoRunSeq: CharInfoRunSeq,
            propList: Prop.PropList,
            transformationCache: RefTab.Ref,
            setTable: ARRAY CharSet OF CharRuns ¬ ALL[NIL]
            ];

        RealCode: TYPE = BYTE;
        RealSeq: TYPE = REF RealSeqRep;
        RealSeqRep: TYPE = RECORD[SEQUENCE size: NAT OF REAL];

        TransformationSeq: TYPE = REF TransformationSeqRep;
        TransformationSeqRep: TYPE = RECORD[SEQUENCE size: NAT OF Transformation];

        CharSet: TYPE = BYTE;

        CharRuns: TYPE = REF CharRunsRep; -- non-overlapping runs, sorted by bc
        CharRunsRep: TYPE = RECORD [
            link: CharRuns, -- self.link.bc > self.ec
            bc, ec: BYTE,
            s: SEQUENCE nt: NAT OF CharRunEntry -- indexed by easy Transformation code
            ];

        CharRunEntry: TYPE = RECORD [
            typefaceIndex: TypefaceIndex,
            charInfoRunIndex: CharInfoRunIndex
            ];

        CharInfoRunIndex: TYPE = NAT;
        CharInfoRunSeq: TYPE = REF CharInfoRunSeqRep;
        CharInfoRunSeqRep: TYPE = RECORD [SEQUENCE size: NAT OF CharInfoRun];
        CharInfoRun: TYPE = REF CharInfoRunRep;
        CharInfoRunRep: TYPE = RECORD [
            xcCodeDelta: INT, -- Add to get translated code
            bits: AmplCorr,
            placementCode: CARDINAL, -- index into data.placementTransformations
            s: SEQUENCE size: NAT OF CharInfo
                <<for compact representation of Kanji and fixed-width portions, if size=1 and bc#ec, then the charinfo applies for the entire range>>
            ];

        AmplCorr: TYPE = PACKED RECORD [
            amplified: BOOL ¬ FALSE,
            correction: ImagerFont.CorrectionType ¬ mask
            ];

        TypefaceIndex: TYPE = NAT;
        TypefaceCellSeq: TYPE = REF TypefaceCellSeqRep;
        TypefaceCellSeqRep: TYPE = RECORD [SEQUENCE size: NAT OF TypefaceCell];
        TypefaceCell: TYPE = REF TypefaceCellRep;
        TypefaceCellRep: TYPE = RECORD [
            fontName: ROPE,
            typeface: ImagerTypeface.Typeface ¬ NIL,
            createDate: BasicTime.GMT, -- for version checking against typeface.created
            type: ATOM -- for version checking against typeface.class.type
            ];

        InfoRepTag: TYPE = MACHINE DEPENDENT {short(0), verbose(1), (255)};
        CharInfo: TYPE = PACKED RECORD [
            SELECT tag: InfoRepTag FROM
                short => [leftExtent, rightExtent, descent, ascent, escapementX, escapementY: RealCode],
                verbose => [overflowIndex: OverflowIndex],
                ENDCASE
            ];

        OverflowIndex: TYPE = NAT;
        OverflowCharInfoSeq: TYPE = REF OverflowCharInfoSeqRep;
        OverflowCharInfoSeqRep: TYPE = RECORD [SEQUENCE size: NAT OF VerboseCharInfo];
        VerboseCharInfo: TYPE = REF VerboseCharInfoRep;
        VerboseCharInfoRep: TYPE = RECORD [extents: ImagerBox.Extents, escapement: VEC, propList: Prop.PropList ¬ NIL];

        FromStream: PROC [stream: IO.STREAM] RETURNS [Data];
        FormatError: ERROR [diagnosis: ATOM, byteIndex: INT];

    END.