[GiDlist] dxf import

[Mark Smith]

Hi Gid Team

Attached are 2 zipped dxf files which are a series of points joined together
with lines.
scaled_profile.dxf is just profile.dxf which has been scaled by 2 factors in
the x & y direction.
If I import scaled_profile.dxf with automatic import tolerance value enabled
& automatic collapse after import, most of the data points are thrown away,
& changing the tolerance seems to have little effect (making it very small
does nothing?). If I disable automatic collapse after import, then do
collapse model I get the same result, if I collapse line & select all
points, again I get the same result BUT if I collapse line & select a small
section then collapse keeps more of my data, repeating this along the
profile till it is all done results in far more data points being retained
than select all & doing it in one go ?

If I import profile.dxf with auto collapse I get a good representation of
the curve, likewise if I do a collapse model or collapse line & select all
everything is as expected.
My question is why do I get different behaviour depending on the size of the
imported model?
& why does the import tolerance value seem to have little or no effect?

Thanks in advance
Best regards
Mark



---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.522 / Virus Database: 320 - Release Date: 29/09/2003



The information contained in this e-mail message (and any attachment
transmitted herewith) is privileged and confidential and is intended for the
exclusive use of the addressee(s). If you are not an addressee, any
disclosure, reproduction, distribution or other dissemination or use of this
communication is strictly prohibited. If you have received this
communication in error, please contact us immediately so that we can correct
the error.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: scaled_profile.zip
Type: application/octet-stream
Size: 6414 bytes
Desc: not available
Url : http://listas.cimne.upc.edu/pipermail/gidlist/attachments/20031009/da852235/attachment.obj

[Miguel A. Pasenau de Riera]

Hi Mark,

The line is well defined internally. The problem is the aproximate
screen representation. If you change the 'curve precision' to 1.0;
in the 'Utilities-Preferences' window inside the 'Graphical' panel
there is a slide with the label 'Curve precision'. If you change this
slide to 1.0, then press 'accept' and after a 'redraw' you'll get
a more acurate representation.

As a general rule, you can mesh the lines and then see if this mesh
matches what you were looking for, because the mesh process uses
the complete and acurate internal representation of the line. To draw
a NURB line GiD makes a coarse mesh. The parameter 'curve precision'
and 'surface precision makes this more or less coarse.

Hope it helps

miguel

-----Mensaje original-----
De: gidlist-admin at gatxan.cimne.upc.es
[mailto:gidlist-admin at gatxan.cimne.upc.es] En nombre de Mark Smith
Enviado el: jueves, 09 de octubre de 2003 12:46
Para: Gidlist (E-mail)
Asunto: [GiDlist] dxf import


Hi Gid Team

Attached are 2 zipped dxf files which are a series of points
joined together with lines. scaled_profile.dxf is just
profile.dxf which has been scaled by 2 factors in the x & y
direction. If I import scaled_profile.dxf with automatic
import tolerance value enabled & automatic collapse after
import, most of the data points are thrown away, & changing
the tolerance seems to have little effect (making it very
small does nothing?). If I disable automatic collapse after
import, then do collapse model I get the same result, if I
collapse line & select all points, again I get the same
result BUT if I collapse line & select a small section then
collapse keeps more of my data, repeating this along the
profile till it is all done results in far more data points
being retained than select all & doing it in one go ?

If I import profile.dxf with auto collapse I get a good
representation of the curve, likewise if I do a collapse
model or collapse line & select all everything is as
expected. My question is why do I get different behaviour
depending on the size of the imported model? & why does the
import tolerance value seem to have little or no effect?

Thanks in advance
Best regards
Mark



---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.522 / Virus Database: 320 - Release Date: 29/09/2003



The information contained in this e-mail message (and any
attachment transmitted herewith) is privileged and
confidential and is intended for the exclusive use of the
addressee(s). If you are not an addressee, any disclosure,
reproduction, distribution or other dissemination or use of
this communication is strictly prohibited. If you have
received this communication in error, please contact us
immediately so that we can correct the error.