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! ###  This file contains information on using the EUKLID Design             ###
! ###  Data Translator on the UNIX platforms SGI, HP and Windows NT.         ###
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! ###  General                                                               ###
! ###                                                                        ###
! ###    New functions                                                       ###
! ###    Licensing                                                           ###
! ###    Documentation                                                       ###
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! ###  Product use                                                           ###
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! ###    Software support                                                    ###
! ###    Customer-specific adaptations                                       ###
! ###    Special data structure characteristics                              ###
! ###    Treatment of scaling                                                ###
! ###    Treatment of invisible elemenmts                                    ###
! ###    Data conversion restrictions                                        ###
! ###    Special characteristics in connection with SIGRAPH-CAD 2D           ###
! ###    Error handling                                                      ###
! ###                                                                        ###
! ###  General notes                                                         ###
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General

   EUKLID Design Data Translator (hereafter referred to as the Data Translator)
   is the IGES/DXF processor of EUKLID Design. It allows to read and create
   IGES, DXF and DWG files. Its functionality can be determined
   through the choice of performance levels and switches in the configuration file.

   The data translator features the following characteristics: 

   1. G1B1 and G1B2 performance levels according to VDAIS, 
      as well as PLUS (logical additions) for IGES
   2. Miscellaneous switches for conversion control
   3. Comprehensive statistics of converted elements
   4. AQL interface prior to and following conversion
   5. Interactive and batch mode (via AQL)

   Please consult the user manual for further information regarding the range
   of functions, etc.

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New functions

   With this release you can read and created DWG-Files.
   AutoCAD versions up to AutoCAD 2008 are supported.

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Licensing

   There is no license necessary to use the Data Translator.
   To use the action for creating DWG-Files within EUKLID Design, there is
   the need to posess a license OD_DWO_NT or OD_DWO_UN.
        
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Working with the Data Translator 

   No prior experience is required to use the data translator. 

   For optimal data transfer between IGES, DXF and DWG-Data and a particular
   CAD system, an extra directory should be established for specially adapted
   reference files; this, however, requires good knowledge of the chosen format. 

   Please consult the user manual for further details.

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Software support

   The IGES Standard definition results automatically in data interpretation
   problems due to the various processors in use. The same applies to the DXF
   and DWG format. This is why the Data Translator is designed to be configurable
   and can be optimally adapted to particular source or destination systems. 

   The same applies to DXF- and DWG.

   Thats the reason why Data Translator is made configurable and can be
   accommodated to different systems.

   Questions or requests in this regard may be addressed to the appropriate
   hotline address.

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Customer-specific adaptations 

   Through use of configuration files, the Data Translator can be adapted to
   particular destination or source systems (see user manual).

   Please use the Config Editor by clicking the corresponding button in the
   parameter file selection menu when first creating this type of file.

   Please note that the preset values are not always displayed correctly if they
   are dependent upon other settings. In case of doubt, you should set the
   desired value explicitly.

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Special data structure characteristics

   The postprocessor creates an EUKLID Design data structure which contains no
   relations and which corresponds approximately to that which is
   created by the function "Redefinition to simple definition types".

   Each object is formed of points. The first is created relative to the origin
   and named depended on the source file 'iges_origin', 'dxf_origin' or 'dwg_origin'.
   All further points are created relative to this first point.

   In addition, points which differ from previously-created points by less than
   the amount defined in ALLG_SYST_EPSL (defined in iges.zuor or dxf.zuor; see
   user manual) are not created, but rather reused. When a point is edited the
   relationships to the linked objects are always retained.

   This distinction is applied separately for the X and Y axes. Points whose
   X coordinates differ from those of the referenced point by less than
   ALLG_SYST_EPSL are created as Y-parallel points. Y-coordinates are handled in
   like manner.

   You can create such coordinates either by objects of type "length" or abso-
   lutely (see configuration file).
 
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Treatment of scaling
 
   Scaling of details cannot be read correctly into EUKLID Design, since only a 
   single scale is used in the IGES file (global section). Details are therefore 
   always created to this (global) scale, which results in the display of detail
   dimensions as theoretical dimensions (i.e. underlined). Unfortunately, this
   cannot be realized with converted dimensions (created as lines and text). 
   
   The same applies to DXF and DWG conversion.

   Scalings can be treated only via the IGES entity "View". For each view an own
   coordinate system will be created.

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Treatment of invisible elements

   IGES entities with status 'blanked' are created in an invisible layer called
   'iges_blanked' erzeugt.
   (IGES only)

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Restrictions on data conversion

   - Splines:

     Fourth order splines cannot be transferred when geometrically correctly
     converted. 
     (when IGES_DRAW is false)

     When IGES_SPLI and IGES_DRAW are both false, splines cannot be transferred
     at all.
     (IGES only)

   - Endless lines:

     Endless lines are transferred as finite lines with end points which may
     lie far outside. When the file is read in again, these lines may not be
     displayed correctly. 

   - Arc length dimensions:

     Arc length dimensions cannot be transferred in performance level G1B1.
     In the PLUS performance level, an angle dimension is transferred, but it
     can be recognized by the PLUS stage as a arc length dimension.
     (IGES only)

   - Object names:

     Names of objects (except for groups and layers) are not transferred.

   - IGES_PATH, DXF_PATH and DWG_PATH switches in the configuration file:

     The path name following <>_PATH is evaluated only interactively. When
     called in AQL using 'input_iges'/'output_iges' the complete file name must
     be specified.

   - Contours (surfaces):

     In IGES, a contour may consist not only of lines and circles (or arcs) as
     in EUKLID Design, but may also be composed of splines.

     Splines are therefore always polygonized within contours and thereby
     included in the contour as approximations (see ALLG_SYST_EPSL in iges.zuor).

   - Hatching:

     In G1B1, hatching is transferred as IGES Entity 106 through use of
     EUKLID Design graphic calculation. This is why hatching
     cannot be transferred in performance level G1B1 when IGES_DRAW is set to
     'false'.

     This does not influence transfer of hatching as IGES Entity 230 in the
     PLUS level.

   - Hide:

     The information that a surface hides cannot be transferred. The Post-
     processor therefore assumes for IGES Entity 230 with Code 0 or 19 (i.e.
     non-hatched) that it should be hidden.

     You can activate the clipping for the output (see configuration file).

   - View treatment:

     View treatment occurs with clipping but only with lines, arcs and circles.

     In connection with Views (Entity 410) and Single Subfigure Definition
     (Entity 308), problems may occur if the IGES file originates from a
     3-D system. In that case, inbound transfer must be carried out using
     switch IGES_USER aufl.
     Other settings result in creation of two-dimensional USER elements
     which of course can then no longer be viewed from other directions.

     The same applies to Viewport and  Block in DXF/DWG.

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Special characteristics in connection with SIGRAPH-CAD 2D

   Visibility:

   SIGRAPH-CAD 2D and EUKLID Design use surface filling to hide other elements.
   In order to obtain the same depiction in the destination
   system, a visibility list is transferred in addition using a Property entity
   (406) of Form 6731. It contains the elements in the same order in which they
   were drawn; i.e. the 'topmost' last.

   Character set:

   The character sets of SIGRAPH-CAD 2D and EUKLID Design vary substantially from
   one another; neither corresponds to the IGES standard.
   In particular the extensions for German-speaking countries are not considered.
   Through use of extended reference files, however, these characters may be
   transferred among these systems. To do so, the following line must be added
   to the configuration file:

        IGES_ZUOR #zuor_ext

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In case of error

   Please use the documentation and the release notes to check whether the
   behavior is a documented restriction.

   The following information is required to diagnose a software error:

   - The most precise error description possible, noting discrepancies from
     the user manual
   - IGES, DWG or DXF file for postprocessor errors
   - modell.mod for preprocessor errors with corresponding user elements
   - the processor running log file
   - the file "iges_aql.err" or "dxf_aql.err" or "dwg_aql.err"
   - the reference files
   - If incorrect graphic depictions or other effects which can only be
     described in visual terms (i.e. as a screen capture) occur during use of
     EUKLID Design, then we need a hard copy of the screen for
     diagnosis.

   Please send all of this information to your appropriate hotline address.

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General notes

Restrictions

   Obsolete functions:

   ---

   Incompatabilities:

   The Data Translator converts all Subfigures or Blocks (DWG/DXF)
   to Groups (there will be no UDO's created).

   In the configuration file you can now only choose

   IGES_USER diss
   or
   DXF_USER diss
   or
   DWG_USER diss

   diss -> dissolve
