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Nicolas Jordan
12-05-2018, 09:14 AM
Problem:
I finally began using LWCAD 2018 skipping the 5.x series completely. So I sent straight from using LWCAD 4.51 in production to LWCAD 2018. I have been using LWCAD 2018 with both Lightwave 2015.3 and 2018.0.7. After using it for modeling a house in LW 2015.3 I noticed that my frame rate took a a huge hit in open GL and felt like I was modeling an object that was millions of polygons. It began slowing and almost freezing up at some points. I could not find anything wrong with the geometry or file itself. When loading the file into modeler it would take a very long time to load and sometimes even crash while loading.

Why I think it's LWCAD causing the problem:
I decided to load the file into Modo and it loads quickly with no problem and is super fast in GL. I saved it back out of Modo as an LWO and loaded that file back into modeler and all the problems where gone. I resumed using LWCAD again and after saving multiple time and working began having the same issues again. Layout also seems to load the LWO fine. The reason both Modo and Layout can load the LWO with no problems is because neither program can read LWCAD nurbs data in the LWO file so I think the problem may be LWCAD specific things being written into the LWO file and even after being deleted it seems they permanently wreck the file. It may be leaving a bunch of garbage in the file or mangling it in some way for LW modeler.

Here are links to the files in my dropbox to test.

LW 2015 LWO file https://www.dropbox.com/s/savm2mi7ez4x6b5/24HudsonDrive_LW2015.lwo?dl=0

LW 2018 LWO file https://www.dropbox.com/s/v1zs812mey2vd7t/24HudsonDrive_LW2018.lwo?dl=0

I have reverted back to using LWCAD 4.51 for now since these problems caused me to miss a deadline on a project already. I'm not sure if LWCAD 5 would cause the same issues but I assume it likely does. I own LWCAD 5 as well but have bothered to use it much.

Please test let me know if you agree with my findings on this issue. I think I will also post this in the LWCAD forum so Viktor can take a look as well.

raymondtrace
12-05-2018, 11:36 AM
I'm seeing similar results. I could not get the 2018 file to load in Modeler and had to kill the process.

A hex editor suggests the top and bottom of the 2018 file is standard LWO. Nothing appears to have been truncated when saving so the error must be in the gooey middle.

jaf
12-05-2018, 02:28 PM
Really large difference in file size 2018 36.23mb to 2015 4.60 mb. I was able load the 2018 version and export as an obj with a size of 16.22 mb. It loads rather quickly in 3DCoat and Rizom. Don't have 2015 on my system right not, but 2018 seems to thrash a long time when doing something like deleting the polylines.

Be interesting to hear what the problem is.

next_n00b
12-05-2018, 03:19 PM
I have noticed one problem with LightWave 2018 and LWCAD 2018 … when I’ve been creating LWCAD specific windows on my own, non LWCAD-made walls, I’ve noticed there wasn’t just a single window which I've created, there were several of them … like ten on the exact same spot. This could be easily noticed with the low-poly count scene, while this problem hasn’t appeared if I made the window on LWCAD-specific wall - in this case, there was only one window on the same spot. Check it out if you have the same problem.

Nicolas Jordan
12-05-2018, 03:29 PM
Really large difference in file size 2018 36.23mb to 2015 4.60 mb. I was able load the 2018 version and export as an obj with a size of 16.22 mb. It loads rather quickly in 3DCoat and Rizom. Don't have 2015 on my system right not, but 2018 seems to thrash a long time when doing something like deleting the polylines.

Be interesting to hear what the problem is.

The most interesting part is the model contained in the file is the same in both 2015 and 2018 format. Yet these both load into other programs fine. I loaded the 36mb 2018 lwo into Modo 12 and saved out again as lwo and it's now 1.46mb in size.

Nicolas Jordan
12-05-2018, 03:33 PM
I have noticed one problem with LightWave 2018 and LWCAD 2018 … when I’ve been creating LWCAD specific windows on my own, non LWCAD-made walls, I’ve noticed there wasn’t just a single window which I've created, there were several of them … like ten on the exact same spot. This could be easily noticed with the low-poly count scene, while this problem hasn’t appeared if I made the window on LWCAD-specific wall - in this case, there was only one window on the same spot. Check it out if you have the same problem.

In my short time using LWCAD 2018 I have come across a few other weird as well bugs but have not been able to reproduce reliably. I will not be using LWCAD 2018 in production anymore after my scary experience with it. I don't know for sure but I have a feeling many of the problems are coming from the new nurbs in LWCAD even though I wasn't really using them much there seems to be something left in the file that accumulates. I will have to see if anything like you describe might be happening in my case.

next_n00b
12-05-2018, 04:21 PM
I have opened only your 2018 lwo. Your problem is definitely your "Front" layer. But I do not know what and why. It is working soooo sloooow. Even undo after delete. What is that, where you got this geometry :)

Nicolas Jordan
12-05-2018, 04:30 PM
I have opened only your 2018 lwo. Your problem is definitely your "Front" layer. But I do not know what and why. It is working soooo sloooow. Even undo after delete. What is that, where you got this geometry :)

The front layer in the 2018 lwo was a dxf file that has been converted to lwo with AccuTrans 3D. There are also a couple guide lines I added that were drawn with the line tool in LWCAD 2018 in that layer that meet up at the origin 0,0,0. What makes you think the contents of the Front layer is causing the issues?

next_n00b
12-05-2018, 04:44 PM
Because there is more than a million polygons. In the middle somewhere I believe.

jwiede
12-05-2018, 05:13 PM
Nicolas, might want to check your LWCAD prefs to make sure you don't have NURBS curve tessellation (or related) set insanely high, that could lead to runaway poly counts when LWCAD tries to convert it to regular geometry for display, etc.

Nicolas Jordan
12-05-2018, 06:41 PM
Because there is more than a million polygons. In the middle somewhere I believe.

If I load the object into Layout where it seems to load fine it says the scene has a total of 11711 Polygons and 12286 Points so that's why I'm thinking whatever is causing the slow down and other issues must be LWCAD specific.

Nicolas Jordan
12-05-2018, 08:23 PM
Nicolas, might want to check your LWCAD prefs to make sure you don't have NURBS curve tessellation (or related) set insanely high, that could lead to runaway poly counts when LWCAD tries to convert it to regular geometry for display, etc.

I just checked to make sure but it doesn't appear to be that either.

Nicolas Jordan
12-14-2018, 10:00 AM
Because there is more than a million polygons. In the middle somewhere I believe.

You were right. I sent the file to Viktor to look at. He finally got back to me and said that there were a million copies of a nurbs line occupying the same space. I have no idea how I would have done that. I guess it could be some weird glitch. I will have to keep a close eye on my stats panel from now on and hopefully catch this kind of thing before it makes a file almost unusable.

jwiede
12-14-2018, 05:42 PM
You were right. I sent the file to Viktor to look at. He finally got back to me and said that there were a million copies of a nurbs line occupying the same space. I have no idea how I would have done that. I guess it could be some weird glitch. I will have to keep a close eye on my stats panel from now on and hopefully catch this kind of thing before it makes a file almost unusable.

That many present seems more likely due to some kind of bug creating them behind the scenes, versus user error.

It not impossible that it was from user error, but it's more difficult than folks realize for a user to accidentally generate a million of anything through "unintentional duplication" -- it requires at least twenty "doubling" actions to cross the "million entities" line (2^19 is only 524288). Further, the last 2-3 of the action would almost certainly be lengthy enough in duration that the user would notice the action's exponential drop in perf.

In any case, I'm sure Viktor will look into it. Glad you got it sorted out!

Nicolas Jordan
12-14-2018, 08:08 PM
I have noticed one problem with LightWave 2018 and LWCAD 2018 … when I’ve been creating LWCAD specific windows on my own, non LWCAD-made walls, I’ve noticed there wasn’t just a single window which I've created, there were several of them … like ten on the exact same spot. This could be easily noticed with the low-poly count scene, while this problem hasn’t appeared if I made the window on LWCAD-specific wall - in this case, there was only one window on the same spot. Check it out if you have the same problem.

This does sound very similar to what happened to me but in my case it was around a million nurbs lines in the same exact spot.

Nicolas Jordan
12-14-2018, 08:11 PM
That many present seems more likely due to some kind of bug creating them behind the scenes, versus user error.

It not impossible that it was from user error, but it's more difficult than folks realize for a user to accidentally generate a million of anything through "unintentional duplication" -- it requires at least twenty "doubling" actions to cross the "million entities" line (2^19 is only 524288). Further, the last 2-3 of the action would almost certainly be lengthy enough in duration that the user would notice the action's exponential drop in perf.

In any case, I'm sure Viktor will look into it. Glad you got it sorted out!

The weird thing is I don't remember using or needing to use any kind of clone or duplication tool of any kind while working on that file so it most likely is some kind of bug or weird glitch causing it. At least I now know what to watch out for now in case it happens again.

jwiede
12-14-2018, 09:36 PM
The weird thing is I don't remember using or needing to use any kind of clone or duplication tool of any kind while working on that file so it most likely is some kind of bug or weird glitch causing it. At least I now know what to watch out for now in case it happens again.

That's kind of what I was getting at... just a single clone/duplication or even a few wouldn't get you near that number unless there were also something broken behind the scenes. The chances of you doing so many clone/duplication ops and not noticing their duration was growing exponentially is even less.

wingzeta
12-14-2018, 10:27 PM
Just a guess. The million instances were created either somewhere along the line in the conversion or import from dxf, because these are automated processes, and it would be difficult to do that by accident by hand. The only question is at which point it happened / got corrupted. If it was at the moment of the LWCAD import, that would be something for Victor to look into, but if it was already in the file before import, than the previous apps in the chain would be the place to look.

Nicolas Jordan
12-18-2018, 10:41 AM
Just a guess. The million instances were created either somewhere along the line in the conversion or import from dxf, because these are automated processes, and it would be difficult to do that by accident by hand. The only question is at which point it happened / got corrupted. If it was at the moment of the LWCAD import, that would be something for Victor to look into, but if it was already in the file before import, than the previous apps in the chain would be the place to look.

It looks like the dxf file was fine. I export a dxf out of DraftSight and import that into Accutrans then export an lwo to load into Lightwave. It also appears the original lwo exported out of Accutrans is also fine. It appears the guide lines I created with LWCAD 2018 were likely the problem. I'm still not sure how it could have happened.