logo
NOTICE:  This is the new PunchCAD forum. You should have received an email with your new password around August 27, 2014. If you did not, or would like it reset, simply use the Lost Password feature, and enter Answer as the security answer.
Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error
History Bug ? (#728)
Options
Go to last post Go to first unread
Previous Topic Next Topic
jol  
#1 Posted : Monday, December 10, 2007 5:18:21 AM(UTC)
jol

Rank: Senior Member

Joined: 2/26/2007(UTC)
Posts: 2,156

Was thanked: 1 time(s) in 1 post(s)
- union 2 objects

- move or flip them to a new location

- remove the union feature from the feature tree

One object is annoyingly returned to it's starting location

Why ?
Back to top
jol  
#2 Posted : Tuesday, December 11, 2007 8:05:42 AM(UTC)
jol

Rank: Senior Member

Joined: 2/26/2007(UTC)
Posts: 2,156

Was thanked: 1 time(s) in 1 post(s)
Isn't this a pretty fundamental flaw in using the feature tree ?
Back to top
billbedford  
#3 Posted : Wednesday, December 12, 2007 3:12:30 AM(UTC)
billbedford

Rank: Senior Member

Joined: 2/19/2007(UTC)
Posts: 186
jol wrote:
Isn't this a pretty fundamental flaw in using the feature tree ?



It's not something that I would do every day.
Back to top
jol  
#4 Posted : Wednesday, December 12, 2007 3:58:54 AM(UTC)
jol

Rank: Senior Member

Joined: 2/26/2007(UTC)
Posts: 2,156

Was thanked: 1 time(s) in 1 post(s)
Bill, I do .. at least every few days .. and I wonder why my model falls apart

We can't have the removal of certain features shooting your part up the history tree .. especially when these parts may have multiple dependencies

It's a bug and it needs fixing - so next time I remove a feature, my model won't fall apart

I don't much care if removing features is not something you do Bill
Back to top
billbedford  
#5 Posted : Wednesday, December 12, 2007 5:43:42 AM(UTC)
billbedford

Rank: Senior Member

Joined: 2/19/2007(UTC)
Posts: 186
jol wrote:
Bill, I do .. at least every few days .. and I wonder why my model falls apart

We can't have the removal of certain features shooting your part up the history tree .. especially when these parts may have multiple dependencies

It's a bug and it needs fixing - so next time I remove a feature, my model won't fall apart

I don't much care if removing features is not something you do Bill


Union is the permanent joining of two objects to make one new one. It is *not* designed as way of temporally joining to objects so that they can be moved in association. The history tree tells you that. If all objects in a union were going to revert to their pre-union position if the union was to be removed then any translations that were done on the unioned object would be copied to each branch of the tree after the union.

If you want to translate objects in association use 'Group'.
Back to top
jol  
#6 Posted : Wednesday, December 12, 2007 6:59:33 AM(UTC)
jol

Rank: Senior Member

Joined: 2/26/2007(UTC)
Posts: 2,156

Was thanked: 1 time(s) in 1 post(s)
eh ?

Thank you Bill ..

you're talking rubbish though

Where in Concepts is a Union defined as a "permanent joining of 2 objects"

In the manual it says "The union boolean (also called add) operation is used to combine two shapes into one."

If it were permanent, then a 'remove feature' would not be allowed, would it ? And it is

.. SolidWorks does not allow you to remove a boolean as I understand

I would be very happy if Concepts forbid this too .. if it avoided this issue
Back to top
Tim Olson  
#7 Posted : Wednesday, December 12, 2007 12:17:47 PM(UTC)
Tim Olson

Rank: Senior Member

Joined: 2/2/2007(UTC)
Posts: 5,447
United States

Was thanked: 502 time(s) in 353 post(s)
Jol,

I believe this behavour is correct. The xform step was a history operation based on a particular node. It does not impact prior nodes or operations. When you remove the boolean, the xform is still there and drops back onto the first block selected for union. The first item selected for a boolean is the object the preserves the tree branching. You will need to remove the Translate operation to get to the previous un translated position.


>>One object is annoyingly returned to it's starting location

It was never moved. The result of the union was moved.
Tim Olson
IMSI Design/Encore
Back to top
API  
#8 Posted : Wednesday, December 12, 2007 7:33:11 PM(UTC)
API

Rank: Senior Member

Joined: 2/19/2007(UTC)
Posts: 129
Tim,
Can you post somewhere a concise set of rules for the History Tree. I don't think that its understood very well. What it means to be the first object picked.
Sometimes I duplicate a part with history. Move the new object to a new layer. If I "remove feature boolean", I get a dialog that the object will go to the parent layer. When I'm all done, I usually can't find it.
Back to top
WWW
jol  
#9 Posted : Thursday, December 13, 2007 4:31:37 AM(UTC)
jol

Rank: Senior Member

Joined: 2/26/2007(UTC)
Posts: 2,156

Was thanked: 1 time(s) in 1 post(s)
Tim, that's a classic Captain Spock answer .. we're carbon units .. and what's more, we're designers !

I see what you're saying .. and in your/ACIS logic, perhaps it's right.

However, with some of this stuff, you need to think what the designer is doing .. and think what the designer is thinking

If the designer moved an object from A to B, then changed it's colour from green to purple .. if he undoes the move back to A .. does the colour of his object change back from purple to green ? No !

The designer has asked that this union is undone .. he has NOT asked that the translate is undone for one of the partner entities only (.. or that any other feature change inbetween is undone). You cannot assume this .. however 'logical' it is

If the intent is in doubt, a dialog should make it quite clear what these 2 options are :

- just undo what I'm asking you to undo
- undo what I'm asking you to undo .. and incur the knock-on effects in ACIS logic
Back to top
jlm  
#10 Posted : Saturday, December 29, 2007 3:08:06 PM(UTC)
jlm

Rank: Senior Member

Joined: 2/18/2007(UTC)
Posts: 1,252
Man
France
Location: Paris & Frankfurt

Thanks: 217 times
Was thanked: 164 time(s) in 101 post(s)
I just spoiled a big project with that :
disassembling complex screw parts that had been moved of a small amount, I got all the threads off centered on the final model...

A feature that can silently spoil your work is worse than a bug !
Back to top
WWW
Users browsing this topic
Guest (3)
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.

Powered by YAF.NET 2.1.2 | YAF.NET © 2003-2024, Yet Another Forum.NET