2003-june.txt

acis说明文档

Message-ID: <v03007803bb1d4b2dc606@[192.168.1.100]>

I agree with Arlo, the Summit was well worth the time.  The format was very
good and Spatial did a great job of listening and making developers and
tech support available throughout the conference.   Next year we're going
to bring more folks from our company.


Tim Olson
President
CADSoft Solutions, Inc
www.concepts3d.com (Precise Conceputal Computer Aided Design)

>While I generally avoid making any statement that might seem like a
>commercial endorsement, I feel compelled to say something about the
>Insider's Summit held at the beginning of June in Westminster.  In the past
>I avoided going, because Spatial seemed a lot more interested in talking
>than listening.  This time was quite different.  A great deal of time was
>given for Spatial's customers to make presentations, and they had a lot of
>folks there just to listen and answer questions.  They really seem to want
>to communicate.
>
>Consider going.  I'll very likely go again, and I've become awfully jaded
>about most conferences..
>
>For what it's worth,
>
>Arlo L. Ames
>[e-mail]
>[phone]
>
>
>_______________________________________________
>Acis-alliance mailing list
>[e-mail]
>http://lists.cs.columbia.edu/mailman/listinfo/acis-alliance



From yhbei at mae.ufl.edu  Tue Jun 24 15:08:26 2003
From: yhbei at mae.ufl.edu (Yanhong Bei)
Date: Tue Jun 24 16:59:38 2003
Subject: [Acis-alliance] connectivity of several bodies
References: <[e-mail]>
Message-ID: <001a01c33a7b$9bc2f720$cd2ae30a@Calcaneus>

Dear All,

I have several entities ( actually they are bodies) in an entity list. I am
trying to find out among them the entities that are connected together. I
tried api_entity_entity_touch() and api_entity_entity_distance(), however,
neither was able to give me the correct results.

Do you think there are other ways to test the connectivity between entities?

Thanks for your help,

Yanhong Bei
Ph.D Student
The Department of  Mechanical
 and Aerospace Engineering
University of Florida
Gainesville, FL, 32611
(Tel: [phone])

From kevin.branshaw at autodesk.com  Tue Jun 24 18:15:29 2003
From: kevin.branshaw at autodesk.com (Kevin Branshaw)
Date: Tue Jun 24 17:18:37 2003
Subject: [Acis-alliance] connectivity of several bodies
Message-ID: <[e-mail]>


Dear Yanhong,

	I don't do any acis coding anymore, but as I recall there is a
function that is named something like "api_boolean_stage_one" that takes
two bodies or perhaps an entity list, and returns a wire or possibly an
entity list of wires.  If nothing is returned, they do not intersect.
This is a relatively cpu intensive function, so I would compare two
bodies minmax boxes to easily identify the bodies you can skip.

Good Luck!
Kevin

-----Original Message-----
From: Yanhong Bei [mailto:[e-mail]] 
Sent: Tuesday, June 24, 2003 2:08 PM
To: [e-mail]
Subject: [Acis-alliance] connectivity of several bodies

Dear All,

I have several entities ( actually they are bodies) in an entity list. I
am
trying to find out among them the entities that are connected together.
I
tried api_entity_entity_touch() and api_entity_entity_distance(),
however,
neither was able to give me the correct results.

Do you think there are other ways to test the connectivity between
entities?

Thanks for your help,

Yanhong Bei
Ph.D Student
The Department of  Mechanical
 and Aerospace Engineering
University of Florida
Gainesville, FL, 32611
(Tel: [phone])

_______________________________________________
Acis-alliance mailing list
[e-mail]
http://lists.cs.columbia.edu/mailman/listinfo/acis-alliance

From alames at sandia.gov  Tue Jun 24 18:01:55 2003
From: alames at sandia.gov (Ames, Arlo)
Date: Tue Jun 24 19:02:37 2003
Subject: [Acis-alliance] connectivity of several bodies
Message-ID: <[e-mail]>

Can you be more specific about your definition of "connected together"?
Functions like
api_entity_entity_distance should be sufficient unless you're looking for
overlap, in which case api_slice/api_imprint/api_boolean_stage_one would
perhaps be better.  The boolean-related calls are rather slow compared to
distance-type calls, but give more complete information (including locations
of the overlaps) in cases where the objects overlap.  If no overlap occurs,
the distance functions will tell you about near misses.  Of course,
"connected" can also mean that they share topology, instead of thinking in
purely geometric terms.  This interpretation is less likely, but I've seen
it.  Detection of topology sharing isn't likely to be found in an api
function.

Arlo Ames


-----Original Message-----
From: Yanhong Bei [mailto:[e-mail]] 
Sent: Tuesday, June 24, 2003 2:08 PM
To: [e-mail]
Subject: [Acis-alliance] connectivity of several bodies

Dear All,

I have several entities ( actually they are bodies) in an entity list. I
am
trying to find out among them the entities that are connected together.
I
tried api_entity_entity_touch() and api_entity_entity_distance(),
however,
neither was able to give me the correct results.

Do you think there are other ways to test the connectivity between
entities?

Thanks for your help,

Yanhong Bei
Ph.D Student
The Department of  Mechanical
 and Aerospace Engineering
University of Florida
Gainesville, FL, 32611
(Tel: [phone])

_______________________________________________
Acis-alliance mailing list
[e-mail]
http://lists.cs.columbia.edu/mailman/listinfo/acis-alliance

_______________________________________________
Acis-alliance mailing list
[e-mail]
http://lists.cs.columbia.edu/mailman/listinfo/acis-alliance

From zz_zxc123 at cims.sjtu.edu.cn  Wed Jun 25 12:33:22 2003
From: zz_zxc123 at cims.sjtu.edu.cn (zhnagxuecchang)
Date: Tue Jun 24 23:36:06 2003
Subject: [Acis-alliance] How to display a part with  color map in acis.
Message-ID: <001801c33aca$89f75b40$0400a8c0@ndserver>

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From fregly at ufl.edu  Tue Jun 24 23:45:34 2003
From: fregly at ufl.edu (B.J. Fregly)
Date: Wed Jun 25 07:11:41 2003
Subject: [Acis-alliance] connectivity of several bodies
References: <[e-mail]>
Message-ID: <01fd01c33ac3$da9ecda0$6101a8c0@princess>

Arlo,

Thanks for your response to Yanhong.

This actually is a topology rather than geometry problem.

We are reading in SAT files created in Rhino 2.0, and the files contain an
unknown number of faces. Some of these faces share common edge curves and
form shells (i.e., groups of contiguous faces), but ACIS does not seem to
recognize this connectivity when the SAT file is read in (though maybe we
are missing something here).

Our goal is to automatically determine which faces should be grouped
together into shells (and eventually bodies for use with various api
functions like api_raytest_body).

I just checked the on-line help, and it appears that a function like
"api_stitch" may do the job for us. We'll poke around there some more and
see if that will work.

Thanks again for your input on this problem.

B.J.

B.J. Fregly, Ph.D.
Assistant Professor
Department of Mechanical & Aerospace Engineering,
Department of Biomedical Engineering, and
Department of Orthopaedics & Rehabilitation (adjunct)
231 MAE-A Building
P.O. Box 116250
University of Florida
Gainesville, FL  32611-6250
Tel: [phone]
Fax: [phone]
E-mail: [e-mail]
Web: http://www.mae.ufl.edu/~fregly

----- Original Message ----- 
From: "Ames, Arlo" <[e-mail]>
To: <mailto:[e-mail]>
Cc: <[e-mail]>
Sent: Tuesday, June 24, 2003 7:01 PM
Subject: RE: [Acis-alliance] connectivity of several bodies


> Can you be more specific about your definition of "connected together"?
> Functions like
> api_entity_entity_distance should be sufficient unless you're looking for
> overlap, in which case api_slice/api_imprint/api_boolean_stage_one would
> perhaps be better.  The boolean-related calls are rather slow compared to
> distance-type calls, but give more complete information (including
locations
> of the overlaps) in cases where the objects overlap.  If no overlap
occurs,
> the distance functions will tell you about near misses.  Of course,
> "connected" can also mean that they share topology, instead of thinking in
> purely geometric terms.  This interpretation is less likely, but I've seen
> it.  Detection of topology sharing isn't likely to be found in an api
> function.
>
> Arlo Ames
>
>
> -----Original Message-----
> From: Yanhong Bei [mailto:[e-mail]]
> Sent: Tuesday, June 24, 2003 2:08 PM
> To: [e-mail]
> Subject: [Acis-alliance] connectivity of several bodies
>
> Dear All,
>
> I have several entities ( actually they are bodies) in an entity list. I
> am
> trying to find out among them the entities that are connected together.
> I
> tried api_entity_entity_touch() and api_entity_entity_distance(),
> however,
> neither was able to give me the correct results.
>
> Do you think there are other ways to test the connectivity between
> entities?
>
> Thanks for your help,
>
> Yanhong Bei
> Ph.D Student
> The Department of  Mechanical
>  and Aerospace Engineering
> University of Florida
> Gainesville, FL, 32611
> (Tel: [phone])
>
> _______________________________________________
> Acis-alliance mailing list
> [e-mail]
> http://lists.cs.columbia.edu/mailman/listinfo/acis-alliance
>
> _______________________________________________
> Acis-alliance mailing list
> [e-mail]
> http://lists.cs.columbia.edu/mailman/listinfo/acis-alliance
>
> _______________________________________________
> Acis-alliance mailing list
> [e-mail]
> http://lists.cs.columbia.edu/mailman/listinfo/acis-alliance
>

From alames at sandia.gov  Wed Jun 25 11:30:12 2003
From: alames at sandia.gov (Ames, Arlo)
Date: Wed Jun 25 12:32:21 2003
Subject: [Acis-alliance] connectivity of several bodies
Message-ID: <[e-mail]>

If you have imported a single solid body, you should have a BODY object with
likely 1 LUMP, which has 1 SHELL, which has a FACE which likely has a next
FACE, and so on.  Each face should have at least 1 LOOP, each of which
should have 1 or more COEDGEs.  Each COEDGE should have an EDGE, and for a
closed object, each COEDGE should have a partner, which refers to the same
edge it did, with opposite sense.

api_check_entity (sp?) can check to see whether you have a valid, closed
solid, and will complain about deviation from what's stated above (along
with complaining about accuracy issues and so on as well.

If you have a bunch of disconnected faces, api_stitch will do the job, IF
they have identical (or near identical) EDGEs to stitch together.  It's
likely your best bet.