PPTC(3g) — Subroutines

Name

PPTC − Packs trimming curve data for the PBSS3D element or primitive.

Operating States: PHOP, ∗, ∗, AROP
PHIGS standard function

Syntax

PPTC (INITFL, LOOPFL, TACRI, LDR, DATREC, TCVF, TSORD, TNKA,
TKNOTS, TPARL, TRTYPE, NTCCP, TPWUA, TPWVA, TPWWA, MLDR, ERRIND,
TCLDR, TCREC)

Argument       Data Type      Access    Description
-------------------------------------------------------------------------
INITFL         Logical        Read      Data record initialization flag
DATAFL         Logical        Read      Data record new loop flag
TACRI          Integer        Read      Trimming curve approximation type
LDR            Integer        Read      Length of the data record array
DATREC(LDR)    Character ∗80 Read      Data record
TCVF           Integer        Read      Trimming curve visibility flag
TSORD          Integer        Read      Trimming curve spline order
TNKA           Integer        Read      Number of spline knots in the array
TKNOTS(TNKA)   Real           Read      Trimming curve spline knots
TPARL(2        Real           Read      Trimming curve parameter range
                                        limits
TRTYPE         Integer        Read      Trimming curve spline rationality
NTCCP          Integer        Read      Number of trimming curve spline
                                        control points
TPWUA(NTCCP)   Real           Read      Trimming curve u control point
                                        components
TPWVA(NTCCP)   Real           Read      Trimming curve v control point
                                        components
TPWWA(NTCCP)   Real           Read      Trimming curve w control point
                                        components
MLDR           Integer        Read      Size of the trimming curve data
                                        record
ERRIND         Integer        Write     Error indicator
TCLDR          Integer        Write     Total number of array elements used
                                        in TCREC
TCREC(TCLDR)   Character ∗80 Write     Trimming curve data record
-------------------------------------------------------------------------

Constants

Defined Argument     Constant     Description
-------------------------------------------------------------------------
TACRI                PWDCA        Workstation-dependent method
                     PCBKCA       Constant parametric subdivision between
                                  knots
                     PCSWCA       Metric, in world coordinates
                     PCSNCA       Metric, in normalized projection
                                  coordinates
                     PCSDCA       Metric, in device coordinates
                     PCDWCA       Chordal deviation, in world coordinates
                     PCDNCA       Chordal deviation, in normalized
                                  projection coordinates
                     PCDDCA       Chordal deviation, in device coordinates
                     PRWCA        Relative, in world coordinates
                     PRNCA        Relative, in normalized projection
                                  coordinates
                     PRDCA        Relative, in device coordinates
                     DCSDCA       Constant subdivision
                     DIDCA        Implementation-dependent method
TRTYPE               PRAT         Rational (4D) control points
                     PNRAT        Nonrational (3D) control points
-------------------------------------------------------------------------

Description

PPTC packs the trimming curve data for the PBSS3D structure element or primitive.

Data Record Information

If TACRI is PWDCA, there is no data record.

If TACRI is PCBKCA or DCSDCA, the data record has the following format:

INTEGER IL    = 1      Number of integer values
INTEGER IA(1) =        Count
        RL    = 0
        RA    = ()
        SL    = 0
        LSTR = ()
        STR   = ()

If TACRI is PCSWCA, PCSNCA, PCSDCA, PCDWCA, PCDNCA, PCDDCA, PRWCA, PRNCA, or PRDCA, the data record has the following format:

        IL    = 0
        IA    = ()
        RL    = 1      Number of reals
INTEGER RA(1) =        Approximation value
        SL    = 0
        LSTR = ()
        STR   = 0

If TACRI is DIDCA, the data record has the following format:

        IL    = 0
        IA    = 0
        RL    = 1    Number of reals
        RA(1) =      Approximation value
        SL    = 0
        LSTR = ()
        STR   = ()