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Elliot Ave
01-18-2013, 08:20 AM
How many polygons is too many? Does Modeler have a max? Does layout have a max?

Sensei
01-18-2013, 08:26 AM
How many polygons is too many?

How many food, water, money or whatever is too many?


Does Modeler have a max? Does layout have a max?

Yes, of course..

Marcia
01-18-2013, 08:56 AM
Originally Posted by Elliot Ave
Does Modeler have a max? Does layout have a max?


Yes, of course..

The software isn't the only factor to consider. Your processor(s), RAM and graphics card(s) all determine the practical limits of what your computer can handle. You're much more likely to max out the hardware before you max out LightWave.

Elliot Ave
01-18-2013, 09:17 AM
I'm using an Intel i7-3770k with 16gbs of DDR3 2400 ram. For graphics I'm using a Nvidia GTX 550 ti. Is there a set number that you can max out at? Or is your only way of knowing you have hit the limit is when the software/computer starts to crash?

3DGFXStudios
01-18-2013, 09:24 AM
In most cases low memory will cause crashes. But why do you want to know a specific value? It all depends on the scene and hardware.

Elliot Ave
01-18-2013, 09:42 AM
Just curiosity i guess. I'm new to Lightwave and was just wanting to know my boundaries.

Marcia
01-18-2013, 10:01 AM
Too many variables to answer that question... When you run into a specific problem, bring it here for help troubleshooting. You may (probably will) discover something other than the number of polygons is the root cause.

Sensei
01-18-2013, 10:02 AM
There is one important limitation in nodes: 32768 bytes per the all data nodes in single Node Editor.
You're learning about this limitation when you are not be able to open saved LWO.

I have made two plugins that fix this.
Global Materials
http://globalmaterials.trueart.eu

and TrueGroup
http://truegroup.trueart.eu

OFF
01-18-2013, 10:09 AM
On my previous project had 23 buildings and dozens of trees, which provided 10 million polygons and a half gigabytes of textures, which equals approximately 24 gigabytes of memory is loaded. I suggest compile a summary table - so much of polygons = so much of load memory, it may be helpful to many.
:)

Sensei
01-18-2013, 11:05 AM
If you're suffering due to lack of memory because of textures, you should use LightWolf's plugin that fix it..

OFF
01-18-2013, 11:11 AM
I did a project for a client - he received as a result the scene with objects and textures, attach to the the project a commercial plug-in I think would not have been right.

Marcia
01-18-2013, 11:23 AM
I suggest compile a summary table - so much of polygons = so much of load memory, it may be helpful to many. :)

Don't double-sided polygons exponentially increase the poly count in layout over single sided polys? Or does it just seem that way? And if you're using subpatch or catmull-clark, your subdivision level would also have to be factored in, right?

Wouldn't it be great if someone wrote a plug-in that could compute expected memory usage on the fly, maybe with a pop-out pie/bar chart showing how much was allocated to polys, textures/nodes, render settings, etc.

OFF
01-18-2013, 11:31 AM
Oh, yes, i forgot about subpatches, but in my scene did not have them. That good idea about ram-computing plugin.

Sensei
01-18-2013, 11:43 AM
Don't double-sided polygons exponentially increase the poly count in layout over single sided polys?

If it's just surface editor toggle, no.

It's simply slowing down ray-casting routine.

Because it has to test whether triangle was hit by ray without immediately rejecting those that're parallel (more or less) to ray.

float d = dot product( ray_direction, normal vector );
if( d > 0.0 ) // triangle normal is same as ray direction, if it's single sided polygon, routine is immediately skipping them.

Renderer can optimize and have two lists of triangles, one for single-sided, second for double-sided polygons. This would eat just a bit of memory, but would save doing above dot product, thus rendering faster.

I have many video tutorials which are using dot product.
http://www.youtube.com/user/TrueArtSoftware/videos?view=0

Marcia
01-18-2013, 11:57 AM
If it's just surface editor toggle, no.

It's simply slowing down ray-casting routine.

Because it has to test whether triangle was hit by ray without immediately rejecting those that're parallel (more or less) to ray.

float d = dot product( ray_direction, normal vector );
if( d > 0.0 ) // triangle normal is same as ray direction, if it's single sided polygon, routine is immediately skipping them.

Renderer can optimize and have two lists of triangles, one for single-sided, second for double-sided polygons. This would eat just a bit of memory, but would save doing above dot product, thus rendering faster.

I have many video tutorials which are using dot product.
http://www.youtube.com/user/TrueArtSoftware/videos?view=0

Thank you, Sensei. [Bows] I am now a subscriber. :)

Elliot Ave
01-18-2013, 12:14 PM
Lots of useful information here. Thanks a lot.

One more question.......Do objects that can't be seen by the camera increase render time? Like an object that's behind a wall.

Sensei
01-18-2013, 12:25 PM
That depends on whether you're using reflections, refractions, GI, and where are lights and their type.

From spot that's currently evaluated there are fired rays in direction of each light source to check whether something is between them, to calculate shadow.
If your not directly visible by camera object will be between light source and spot, it will be affecting render times.
Especially if it's transparent object. Shadow calculation must take transparency into account.
If you've f.e. dielectric material used, difference in time might be even noticeable.

jeric_synergy
01-18-2013, 12:36 PM
There is one important limitation in nodes: 32768 bytes per the all data nodes in single Node Editor.
I guess it's moot since you provide a solution right there, but what does that mean?? The amount of flowing 'along the pipes', or the amount of data all the nodes cumulatively bring into the Node Editor, whether they are used or not? Or, probably, something else entirely?

Really, just wondering: I doubt I'll ever even approach that limit.

Sensei
01-18-2013, 12:57 PM
Make sphere.
Save lwo in Modeler.
Write file size on paper.

Then start adding Standard material in Node Editor.
Add one. save. write file size.
Add another one. Save. Write number of bytes. Subtract sizes on paper.

And you pretty much know how many Standard materials you must add to exceed 32k limit..

Or simply make 16 standard material, then select them as group, and copy and paste, save, copy and paste, save.
If you will exceed limit, there will be warning, "can't save file".
But file is written on disk for real (so overwriting any existing)
If you will try loading it, there is message, "can't load file".

jeric_synergy
01-18-2013, 01:02 PM
But file is written on disk for real (so overwriting any existing)
If you will try loading it, there is message, "can't load file".
OOooooo, that is an ugly destructive BUG.

I assume NewTek has been advised?

Besides using your Nodes in the first place (which requires knowing the bug exists, plus good practices), is there any way/workaround (there's that word again) to salvage the geometry? Load it into Blender or something?

Sensei
01-18-2013, 01:48 PM
The more envelopes you have, the more keys, the more nodes, the quicker limit is exceeded.


I assume NewTek has been advised?

Everybody who is working professionally in LW know about this since v9.0.


is there any way/workaround (there's that word again) to salvage the geometry?

I am thinking about utility that will recover it.

jeric_synergy
01-18-2013, 02:19 PM
Everybody who is working professionally in LW know about this since v9.0.

I am thinking about utility that will recover it.
If the utility can do the "least amount of damage", ie remove only the minimum amount of cruft, this of course would be optimum. Just sayin'.

Sensei
01-18-2013, 02:34 PM
I loaded damaged LWO in TrueLoad, and looked what chunks are detected. And there is mess. Even global IFF chunk size (at offset + 4) is screwed..
No surprise Modeler is immediately crashing after trying to load it.

Limit might be 64 kb, if it's unsigned short, not signed short.

jeric_synergy
01-18-2013, 03:24 PM
sounds like it's looping around inside the memory space. That's kinda a big deal.

fazi69
01-19-2013, 04:54 PM
For box it will be exactly seven polygons.