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d1wojo
01-12-2009, 11:07 AM
I create a disc with 24 sides. Then selecting 3 of the points then going to the select loop button. I hit the button but nothing happens. ???? Am I doing anything wrong....

colkai
01-12-2009, 11:20 AM
it depends how you selected the 3 points, you have to select them in order and they must be adjacent.

kojean
01-13-2009, 06:12 AM
I've found that select loop doesn't work for me on the ends or outer edges of certain objects, but it works in the inner loops.

colkai
01-13-2009, 07:06 AM
Weird, I just created a 24-sided disc, grabbed a couple of points and ran it with no problems. Can you give a specific example I can check on?

Hopper
01-13-2009, 07:15 AM
Select Loop and Select Ring has always failed miserably for me. It never selects the obvious and only serves to make me angry. I removed it from my tool set because it only works about 20% of the time.

Jim M
01-13-2009, 10:11 AM
select 2 points or polys.... or 1 edge. It just works 100% of the time.
also when a loop is fully selected you can add to the selection with other loops.

Hopper
01-13-2009, 10:33 AM
select 2 points or polys.... or 1 edge. It just works 100% of the time.
also when a loop is fully selected you can add to the selection with other loops.
I disagree. Unless you are speaking of the absolute mathematical definition. The problem is not that it's broken, it's that there is no way to decide mathematically "which" is the loop the user wants. If I have 2 points selected and one of those points shares a vertex with multiple polygons, there is no way for the code to determine the correct loop. It can only guess.

If it has worked for you 100% of the time, then you have been using it only in situations where there is only one "loop" or "ring" solution.

Jim M
01-13-2009, 10:45 AM
I see your point, and yes I only use it for those situations.

RollerJesus
01-13-2009, 10:52 AM
"60% of the time, it works every time!"
http://4.bp.blogspot.com/_FiNhXIv5StE/SLaVZPVjR5I/AAAAAAAACEs/heGXSMWlwxw/s320/bfantanair8.jpg

Sorry, couldn't help it.

Hopper
01-13-2009, 10:53 AM
Well, maybe I am being a bit harsh when saying it fails miserably. It does what it can in the right situations. It's more or less knowing when you will get the expected results.

Hopper
01-13-2009, 10:56 AM
"60% of the time, it works every time!"
Sorry, couldn't help it.
Awesome. I can just hear the cheesy announcer type voice (like Billy D. Williams) to go along with it too. Excellent!

RollerJesus
01-13-2009, 11:02 AM
Haha! Anchorman kills me...

Seriously though, I was under the same impression as Colkai... You select 3 adjacent points, clockwise, and that will 'set' the loop you want selected, then run the command.

Hopper
01-13-2009, 12:04 PM
True, but the key is to select the "correct" adjacent points (or edges). Take the simplistic example in the pics. In the first example, the system can't determine mathematically what loop to select, so it simply doesn't do anything even though visually you can see what it "should" select. In the second example points on different vertices within the same loop are selected, but now the system can determine what loop is available.

Even though this is a simplistic example, you can see where it is a problem when you have a complex model and the "correct" selection of points or edges may not be terribly obvious.

It's not a bug in the tool, just a limitation between the visualization of what the "loop" is and the mathematical function determining the solution.

colkai
01-13-2009, 02:04 PM
True, there are situations where the "loop" doesn't go where you'd expect, the problem of course is point order etc.. What seems logical from a human POV isn't easy sometimes to define for a computer.

JeffrySG
01-13-2009, 02:21 PM
Yeah it works for me pretty much every time I expect it to work. There are many times where a model has broken or split loops so you may need to do a second selection or deselect some points.

kojean
01-13-2009, 03:59 PM
Here's what I'm seeing. From the comments, I guess I'm expecting the wrong thing. I assume the polygon filling the end cap is causing problems and maybe this isn't technically considered a loop.

1. desired selection:

http://www.newtek.com/forums/attachment.php?attachmentid=68146&d=1231887017

2. point mode: select loop does nothing (with 2 or 3 adjacent points selected)

http://www.newtek.com/forums/attachment.php?attachmentid=68147&d=1231887025

3. point mode: select ring

http://www.newtek.com/forums/attachment.php?attachmentid=68148&d=1231887029

4. on a disc with 2 segments, select loop will work as expected with the middle points selected below to select all of the points all the way around the object

http://www.newtek.com/forums/attachment.php?attachmentid=68153&d=1231887329

kojean
01-13-2009, 04:03 PM
Continuing my previous post due to the attachment limit.

The same thing occurs with edge selection.

5. desired selection

http://www.newtek.com/forums/attachment.php?attachmentid=68154&d=1231887658

6. edge mode: select loop does nothing (regardless of whether one, two or more adjacent edges are selected)

http://www.newtek.com/forums/attachment.php?attachmentid=68155&d=1231887663

7. edge mode: select ring

http://www.newtek.com/forums/attachment.php?attachmentid=68156&d=1231887668

Again it, select loop will work as intended if the object has 2 or more segments and an edge of one of the inner segments is selected.

8. point mode: select loop will not give me the desired selection below. If I select two adjacent points, then select loop, only the third point on one side will be added to the selection.

http://www.newtek.com/forums/attachment.php?attachmentid=68157&stc=1&d=1231888073

JeffrySG
01-13-2009, 09:14 PM
In most programs I've used endcaps don't select as loops. I've just stopped trying to select them that way. Not sure why that is but I imagine it has to do with the was the software is seeing thee flow in those areas.

JeffrySG
01-13-2009, 09:16 PM
If you want a quick way to select them you can select the face and convert the selection to points.

Tobian
01-14-2009, 05:01 AM
Loop selection is far to useful to ditch, despite it's flaws... I can manually select any it missed! It's better than doing it ALL by hand/eye! :)

kojean
01-14-2009, 05:01 AM
In most programs I've used endcaps don't select as loops. I've just stopped trying to select them that way. Not sure why that is but I imagine it has to do with the was the software is seeing thee flow in those areas.

If you want a quick way to select them you can select the face and convert the selection to points.
Thanks for the explanation. I assumed my expectations were wrong, but when I saw this thread I thought I might ask and see if there was some secret I was missing.

Thanks for the good tip. That will work well for selection in the perspective window. For some shapes, I can also use the right click draw selection in quad view, but then I might have to deselect a few stray points.

evenflcw
01-14-2009, 07:37 AM
In most programs I've used endcaps don't select as loops. I've just stopped trying to select them that way. Not sure why that is but I imagine it has to do with the was the software is seeing thee flow in those areas.

Good thread. And the loop selection as it works currently is good to, but...

The algorithm used in the command is not enough. I don't think there should be much of a problem to make it handle atleast the cylinder (with or without the cap). It is not a valid edgeloop as the term is used when modeling, but it is certainly an edge flow that can be clearly distinguished and defined, np?

The box example can't be made to work for the same reason as the earlier example, the edge flow branches, so there are multiple choices.