Disappearing objects issue

Coronel · 29 Jul 2009, 11:31

I'm not an expert (just 3 months) but I already made all my apartment with furnitures in SU so I have some experience now and I'm getting a problem now with a low size model where some parts are disappearing in random order when the point of view is rotated. I de-installed the latest plugins but the problem persists. I tried different visual depths and modes in SU also.

I made a copy of the model on a new document too. The program works fine with other documents.

Any idea?

Jim · 29 Jul 2009, 13:40

Coronel,

It sounds like a known problem called clipping. (see here for Google's explanation .)

Clipping looks like the following:

Coronel · 29 Jul 2009, 14:57

Thank you Jim.

I think it has to be something related to measures in model as you point. I was probably scaling so far my model to make an interception of two groups that I was getting bad results from.

Anyway I must say that when it happens to me, the objects disappeared don't return back when the document is reopened and manipulated again; contrary to google team this cause permanent damage to my model so I must be careful when resize it the first time.

Chris Fullmer · 29 Jul 2009, 15:01

If they diapeeared and don't come back, they could have been deleted. There are plenty of ways to inadvertently delete things. Clipping though, is not one of them. So if stuff is being deleted, watch out for that.

Is it possible that you had hidden it, and then never unhid it? Using "Unhide All" is deceptive as it does not unhide nested objects, for example.

Chris

prismcnd · 29 Jul 2009, 19:41

I found that the clipping issue can be resolve by switching from perspective view to parallel projection and zooming out then switching back to perspective view

Coronel · 29 Jul 2009, 22:56

I have again an empty document and the backup I made. I did a try using your method prismcnd but not luck. Even the document size has changed from the original so there is no model to restore.

This is a terrible bug, it can happen at any moment.

Chris Fullmer · 30 Jul 2009, 00:16

Its very odd. I've never seen it reported before. Has it happened more than once to you? Could you upload a model where it happened?

Chris

Coronel · 30 Jul 2009, 03:12

Here it is.

Was trying to make a base model of winnie pooh planing to try the sculpt tools plugin to pulish it on a final stage.

There are several versions, some simplified (I started again the model to discard file corruption).
One of them is empty and you will see another with some parts disappeared.

You can reproduce the problem using the scale tool for instance and panning the model.
This is the first time I get this trouble. In the beginning was suspecting on the scale I used to intersect the different groups and then resizing the model again, but when I did the second one the problem persists.

Coronel · 30 Jul 2009, 03:20

Thank you Chris.

This is why I clarified that I have some experience now... hahaha

I was making some probes and getting the xtrange behavior. Show hidden geometry, unhidding... it was the same. I didn't delete anything, a simple pan or zoom with the mouse and some groups disappeared.

mac1 · 30 Jul 2009, 05:24

@coronel said:

Here it is.

Was trying to make a base model of winnie pooh planing to try the sculpt tools plugin to pulish it on a final stage.

There are several versions, some simplified (I started again the model to discard file corruption).
One of them is empty and you will see another with some parts disappeared.

You can reproduce the problem using the scale tool for instance and panning the model.
This is the first time I get this trouble. In the beginning was suspecting on the scale I used to intersect the different groups and then resizing the model again, but when I did the second one the problem persists.

some obversation => maybe this will help. Ref winnebz.After downloading exploded the group twice to also get the nose, selected all and regrouped. After that could scale and Pan ok, before was getting weird results??

Coronel · 30 Jul 2009, 12:01

So you get problems without exploding it too?

I did what you say and it works, but I need to mantain the nose grouped and this one is already in one group and scaled close to the final size. But if you take a look at "winnie3" you will see that the body is not there, I just intersected one leg, grouped all and suddenly was erased when I tried to scale the entire model.

I'm trying to reproduce all the steps I did before it happens but don't see nothing special.

Coronel · 30 Jul 2009, 14:44

Don't worry if you can't do anything. A friend of mine offered me to solve the problem definetively.

mac1 · 30 Jul 2009, 17:59

@coronel said:

Don't worry if you can't do anything. A friend of mine offered me to solve the problem definetively.

My guess at your problem.
When I initially download the winnebz model and double click on the group it disappears; if I select all from the tool bar and do a zoom extents nothing shows up but if I do the same under the group sub menu under edit, after select all, I get a strange display. If you do a reset scale at the downloaded group level you get a huge model height of >= 10 million cm. So it appears you have scaled down so far SU can not handle this. If you use the tape tool to scale down form the big dimensions(exploded case) things seem to work ok.
Hope this helps and I am not making an error

Coronel · 30 Jul 2009, 18:37

Ok, it was my first impression but I didn't know how to make the workaround. I was scaling up until the intersection worked.

Anyway if SU can't handle it should advert you before doing xtreme transformations, it may be dangerous... Clint could get very hungry.

hahahaha

Thank you mate!

mac1 · 30 Jul 2009, 20:00

@coronel said:

Ok, it was my first impression but I didn't know how to make the workaround. I was scaling up until the intersection worked.

Anyway if SU can't handle it should advert you before doing xtreme transformations, it may be dangerous... Clint could get very hungry.

hahahaha

Thank you mate!

I rememebr reading about a scale limit in user manual or?? but cannot find it now. I even tried iterative incremental scales by exploding, select all, scaling like .10, regrouping and saving. About three steps the problem comes back so there seems to be some subtle difference between scale and tape re-size that is not clear in the user manual I can find.

Can you clarify scaling up? it looked to me like scaling down was the problem because the posted model has a group box dimension of 75cm while the re-scale value is the very large number??

Coronel · 30 Jul 2009, 23:44

@mac1 said:

Can you clarify scaling up? it looked to me like scaling down was the problem because the posted model has a group box dimension of 75cm while the re-scale value is the very large number??

Yes, it was originally set to 60 or 70 cm but when I tried to make the intersections they failed so I scaled up gradually the model until it worked. Next is when I scaled down the model to the original size again but I didn't use the tape method, just the scale tool, and probably it caused the problem. In the document you say I could get the complete model to 75 cm but in other versions I couldn't or not entirely.

It was easier to make the rest of the room of my little son

mac1 · 31 Jul 2009, 02:35

@coronel said:

@mac1 said:

Can you clarify scaling up? it looked to me like scaling down was the problem because the posted model has a group box dimension of 75cm while the re-scale value is the very large number??

Yes, it was originally set to 60 or 70 cm but when I tried to make the intersections they failed so I scaled up gradually the model until it worked. Next is when I scaled down the model to the original size again but I didn't use the tape method, just the scale tool, and probably it caused the problem. In the document you say I could get the complete model to 75 cm but in other versions I couldn't or not entirely.

It was easier to make the rest of the room of my little son

For what is worth my search found this on pg 620 of the user manual :

"Use the Scale Tool to re-size and stretch portions of geometry relative to other entities in
your model. Activate the Scale Tool from the Modification Toolbar (Microsoft Windows), the
Tool Palette (Mac OS X) or the Tools menu.
Keyboard Shortcut:S
Note - A Global Scale is an operation whereby the entire model is
scaled simultaneously by applying a desired dimension to the distance
between two points. The Scale Tool is only intended to perform scaling
operations on portions of your model (not the entire model). Use the Tape
Measure Tool's global re-scale functionality to perform global scaling
operations." I don't know what this really means, have posted a question in the help group.
Nice rendering

Chris Fullmer · 31 Jul 2009, 04:12

Here is how to do a glbal scale using the tape measure tool.

Measure an object with the heasing tape tool. The side of the desk would be a good object. Lets say it measures as 1.5m. Right as you finsih measuring it, type 15m and hit enter (that is 10 times larger). It will scale everything in the model up by 10 times. That is a global scale.

If you do that inside a group or component, the scaling will only affect the group or component that you are editing, not the entire model.

Chris

mac1 · 31 Jul 2009, 14:34

@chris fullmer said:

Here is how to do a glbal scale using the tape measure tool.

Measure an object with the heasing tape tool. The side of the desk would be a good object. Lets say it measures as 1.5m. Right as you finsih measuring it, type 15m and hit enter (that is 10 times larger). It will scale everything in the model up by 10 times. That is a global scale.

If you do that inside a group or component, the scaling will only affect the group or component that you are editing, not the entire model.

Chris

Thanks Chris for your effort to respond
I have read page 620 of the user manual and know the tape tool is supposed to be used for global scale and the scale tool for relative scale and know how to use both tools. The question in my mind is this: I can scale a total group using the scale tool and things seem to work fine but, for this problem, that does not seem to be the case. If that is done for this case the cited problem comes up even when it is done in the context of the group ( when I double click on the winnebz model). This model has a nested component ( nose) and if the operation is done after exploding this then you can use the scale tool. Using the scale tool the reset scale menu is active but not if one uses the tape tool so there is a very important but subtle difference that should be throughly explained for the user. After a fairly extensive search for info on scaling pg 620 comment in the user manual was the only remotely relevant comment I could find.
If the group or component I am scaling is the total model then??
I opened a question in the group help to see if someone has further clarification.

Coronel · 31 Jul 2009, 14:50

@unknownuser said:

If the group or component I am scaling is the total model then??
I opened a question in the group help to see if someone has further clarification.

I agree with you, that's why I was not afraid of using the scale tool in my case.