Module name: su_exnmg

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Module declaration: GLOBAL GEOMETRY MODULE su_exnmg

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Module description:

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su_exnmg

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Store a VARKON CUB_SUR surface as a NMG bicubic surface.

Output: A text file surname.F07 in the bicubic F07 (NMG) format

----- Description of the data in the F07 file -------------------

The order of the patches:

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IU=1,IV=NV IU=NU,IV=NV

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! ! ! ! ! ! !

! 13 ! 14 ! 15 ! 16 ! 17 ! 18 !

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! ! ! ! ! ! !

! 7 ! 8 ! 9 ! 10 ! 11 ! 12 !

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! ! ! ! ! ! !

! 1 ! 2 ! 3 ! 4 ! 5 ! 6 !

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IU=1,IV=1 IU=NU,IV=1

(Loop index iu= IU-1 and iv= IV-1 in program below)

Surface data header:

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Surface name Total_number_of_patches (Line 1)

YTA/1 594 ( Ex. )

Patch data header:

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I1 I2 I3 I4 I5 I6 I7 I8 I9 I10 (Line 2)

1 48 1 0 1001 0 0 34 19 0 ( Ex. )

where

I1 = 1 (always one)

I2 = Number of records (coefficients) = 48 for bicubic patch

I3 = Patch number in file

I4 = 0 (always zero)

I5 = Surface type = 1001 for bicubic surface

I6 = 0

I7 = 0

I8 = Number of U lines in the surface

I9 = Number of V lines in the surface

I10 = 0 (always zero)

The order of the coefficients for a patch:

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Line Coefficients ( for ) Coefficients ( for )

1 a00x a00y a00z (1.0 * 1.0 ) a10x a10y a10z (U * 1.0 )

2 a20x a20y a20z (U**2 * 1.0 ) a30x a30y a30z (U**3 * 1.0 )

3 a01x a01y a01z (1.0 * V ) a11x a11y a11z (U * V )

4 a21x a21y a21z (U**2 * V ) a31x a31y a31z (U**3 * V )

5 a02x a02y a02z (1.0 * V**2) a12x a12y a12z (U * V**2)

6 a22x a22y a22z (U**2 * V**2) a32x a32y a32z (U**3 * V**2)

7 a03x a03y a03z (1.0 * V**3) a13x a13y a13z (U * V**3)

8 a23x a23y a23z (U**2 * V**3) a33x a33y a34z (U**3 * V**3)

... empty line (no data) ...

Order of coefficients in VARKON's GETCUBP output vector

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data( 1) = a00x data( 2) = a00y data( 3) = a00z

data( 4) = a01x data( 5) = a01y data( 6) = a01z

data( 7) = a02x data( 8) = a02y data( 9) = a02z

data(10) = a03x data(11) = a03y data(12) = a03z

data(13) = a10x data(14) = a10y data(15) = a10z

data(16) = a11x data(17) = a11y data(18) = a11z

data(19) = a12x data(20) = a12y data(21) = a12z

data(22) = a13x data(23) = a13y data(24) = a13z

data(25) = a20x data(26) = a20y data(27) = a20z

data(28) = a21x data(29) = a21y data(30) = a21z

data(31) = a22x data(32) = a22y data(33) = a22z

data(34) = a23x data(35) = a23y data(36) = a23z

data(37) = a30x data(38) = a30y data(39) = a30z

data(40) = a31x data(41) = a31y data(42) = a31z

data(43) = a32x data(44) = a32y data(45) = a32z

data(46) = a33x data(47) = a33y data(48) = a33z

The function checks that there are no NULL patches in the surface.

The parameterization is also checked. Global parameters shall be

integers defined by the patch adress IU,IV.

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Algorithm

1. Initializations and check of input data

Open file. Exit with error if file already exists on

the active JOB directory

Retrieve surface type and number of patches in U and V direction

Write header

Write patch data

Close output file

Module parameters:

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REF s_id >"@t16 Select a CUB_SUR surface";

STRING surname*24:="MySurf" >

"Surface name (will also be file name with .F07 added)" );

No called modules

This document was created 2006-04-01 by module m_extdoc1