<<>>
    <<ImagerScanConverterPrivate.mesa>>
        <<Copyright Ó 1988, 1990, 1991 by Xerox Corporation.  All rights reserved.>>
        <<Michael Plass, May 28, 1992 9:32 am PDT>>
        <<>>
    DIRECTORY
        ImagerScanConverter USING [Pair],
        Scaled USING [Value],
        SF USING [Box];

    ImagerScanConverterPrivate: CEDAR DEFINITIONS
    ~ BEGIN

        Pair: TYPE ~ ImagerScanConverter.Pair;
        RealBox: TYPE ~ RECORD [min, max: Pair ¬ [0, 0]];

        ExternalHalfPlane: TYPE ~ {sLo, sHi, fLo, fHi};
        Region: TYPE ~ PACKED ARRAY ExternalHalfPlane OF BOOL;

        AreaState: TYPE ~ {nil, awaitMove, awaitLine, complete, completeMonotone};

        Edge: TYPE ~ REF EdgeRep;
        Edges: TYPE ~ REF EdgeRep;
        EdgeRep: TYPE ~ RECORD [
            sMin: INTEGER,    -- First scan line touched
            sCount: NAT,    -- Number of scan lines touched
            f0: Scaled.Value,    -- Initial value of f
            df: Scaled.Value,    -- df/ds
            wrapDelta: INTEGER,    -- for wrap computation
            link: REF EdgeRep
            ];

        Area: TYPE ~ REF AreaRep;
        AreaRep: TYPE ~ RECORD [
            bounds: SF.Box,    -- For clipping as the area is built
            realBounds: RealBox,    -- Floating-point version of same
            tightBounds: SF.Box,    -- Computed bounding box of area
            state: AreaState,    -- Indicates state of outline
            moveCount: INT,    -- Number of MoveTo calls
            firstPt: Pair,        -- Argument of most recent MoveTo
            firstRegion: Region,    -- Region of most recent MoveTo
            lastPt: Pair,        -- Most recent point inserted
            lastRegion: Region,    -- Region of lastPt
            totalCrossings: INT,    -- Total number of scan-line crossings
            increasingEdges: Edges,    -- Edges that were increasing in s
            decreasingEdges: Edges,    -- Edges that were decreasing in s
            freeEdges: Edges,    -- Avail list of edges for reuse
            mode: INTEGER,    -- Scan conversion mode
            tolerance: REAL,    -- For subdividing curves
            cLimit: INTEGER,    -- For bounding worst-case subdivisions (curve, conic)
            pLimit: INTEGER    -- For bounding worst-case subdivisions (parabola)
            ];


    END.