Strange Behaving File

KENTUCKY · 11 Jun 2014, 16:58

Hello,
Not sure this is a bug, but it is at least strange behavior, and I am unsure what is causing it. I figured this would be the best spot to post.

I have received two files (skp) from a client recently that are exhibiting strange behavior.
I have only experienced the behavior with files from this particular client.

Lines that they have imported from CAD are jagged and as you rotate around the model the appearance of the jagged line changes. It becomes more jagged in spots and less jagged in others. Like they are jumping around or jittering.

Faces appear/disappear as I move around in the model. These aren't faces right on top of another face or anything like that. Single faces just disappearing.

When double clicking to edit a component it disappears. This is not a view/component edit issue. It is as if the field of view has changed. The entire model disappears when I double click the component. If I zoom way out I finally see the whole model but it disappears when I zoom all the way in. Exit the component and everything is back to normal.

I would think that there was a graphics card issue, if I had not tested the file on multiple computers. I have also in 10 years never encountered this behavior with any other files. I have copied and pasted everything to new files with no luck.

The file is too large to post. 20+MB

Thanks for any input you might have.

Jim · 11 Jun 2014, 22:04

This brings to mind 2 things. Check the scale of the model - it may be very large or very small.

Check the distance the model (and components) are from their origins. Geometry that is very far away from the origin can act strangely.

Do I remember a plugin by thomthom that attempted to fix these issues?

TIG · 11 Jun 2014, 22:13

Sounds like you have an extents issue, causing clipping-planes etc...
The CAD import rings alarm bells...
SketchUp has display issues if objects are very far from the origin.
There are also issues if the geometry inside a component is near the model origin BUT the origin of the component is miles away.
These can occur with CAD based geometry - especially if the origin is preserved, which in a CAD file can be miles from the objects.
Also is a wrongly scaled block has been imported in the CAD file and scaled to suit it can appear OK but the definition itself can be thousands of times too big !

Use Model Info > Statistics > Purge Unused and also Fix Problems in case there's something needing fixing...

Now check if the Model's origin [RGB crossing axes] is near the main objects...
First switch all Layers ON, Guides ON and View > Hidden Geometry ON too...
Switch on Axes.
Zoom extents can you still see everything ?
If no go back and use Edit > Select All
Entity Info will show lots of things selected.
Now hold Ctrl+Shift and 'Select' everything with a right>left fence so it is removed from the Selection.
If the Entity Info still shows a few things try <delete> get rid of them... these are way off from the origin and no use anyway.

If the whole model seems miles from the origin... Select All and Move, choose a logical insertion point [e.g. a corner], type [0,0,0] (or perhaps ';' is your locale's separator?) - the selection jumps to the origin. remake any pre-saved Scene-tab views to suit...

If the issue still continues - Model Info > Components > Show Axes...
If any seem to have an insertion point miles from their geometry, then use the context-menu on them to Change Axes...

Look through the Component Browser and if any pf the Model's components' images are 'blank' this is a possible indication of an issue with an origin.

Also, in the Model select component instances in turn... and if the context-menu has an option to Scale Definition use it... If there is more than one instance and they have different scales use the Make-Unique option first... This ensures no gigantic definitions with scaled down instances...

KENTUCKY · 12 Jun 2014, 02:27

Thanks for the suggestions. I really appreciate the help.
I initially (prior to posting)did most of the suggested items without any luck.
I'll go back through the suggestion and see if anything helps.
Gut feeling is that is the distance from the origin.
The client is doing the initial cad import and setting up a basic site plan.
I'll report back once I have gone back through everything that has been mentioned.
Thanks again

TIG · 12 Jun 2014, 08:58

Some CAD users set their geometry in a 'real-world' miles from some datum at the origin 0,0,0
That way any 'coordinates' they get in CAD are geo-located.
This means that if you import it into SketchUp and keep the CAD origin the geometry is miles away from the Model origin, and Sketchup hates that !
Even if you let SketchUp choose an origin based on the bounds.min of the geometry it can cause issues, if for example there's a bit of geometry/point/xline near the CAD origin, or theres a block that becomes a component with its insertion-point/origin at 0,0,0, but its geometry miles away...

KENTUCKY · 12 Jun 2014, 16:55

I exploded the group containing the site model and the jagged lines and flashing/ appearing disappearing faces issue disappeared.
I regrouped them and don't see any issues?

KENTUCKY · 12 Jun 2014, 17:09

I ran through the list of suggestions. Turns out the model was 642 miles from the origin.
There were no other apparent issues. I moved the model to the origin and that has taken care of the field of view issue when editing a component.
The disappearing faces jagged lines are still an issue. The issue has changed slightly. The site is grouped together. The jagged lines and disappearing faces issue is there until I enter the group, then everything goes back to being smooth with no disappearing faces. Before it was jagged and disappearing/reappearing faces all the time.
Thanks for all the help!

numerobis · 12 Jun 2014, 20:41

@kentucky said:

I exploded the group containing the site model ...
I regrouped them and don't see any issues?

The origin of the old group was 642 miles away from the model. Now after you moved it to 0,0,0, exploded and regrouped it the group has a new origin.

KENTUCKY · 12 Jun 2014, 21:06

I don't know if I follow you completely.
The group was 642 miles away from 0,0,0. The groups origin was right with group,(Model info/components/show axes) not way off far away. The groups origin moved with the group to 0,0,0.
https://www.filesanywhere.com/fs/v.aspx?v=8b6d668a5e6274ac73a3
here is a link to download the file. The file is post move to the origin, pre-explosion of the group.

Box · 13 Jun 2014, 01:10

Zoom out and you will start to see the true origins of various components appearing at some distance. The origin of a group or component needs to be near itself or you get clipping etc.