Geometry exporting issue in Reality 4 vs Reality 2

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Geometry exporting issue in Reality 4 vs Reality 2

Postby Virgorival » Wed Apr 18, 2018 1:42 am

Ok So i made this post in the Reality Plug in forums with any luck of a response to what might be going on

But i just need some kind of confirmation.

the issue Reality 4 has always had has been bothering me since the day it was released and while i found a work around for it
But i'm starting to wonder if this issue might have something to do with the loss of rendering quality R4 has had compared to R2

I keep going back to my old Reality 2 renders and amazed on how much cleaner and crisper the sample seem to be compared to my current work
I'm going to copy and past my post from the reality forums to here
which was meant to show how to get around the issue i was presenting

"""" This is a table prop from Suite 2101 https://www.daz3d.com/suite-2101
that i noticed creates this issue
Image
This is what it looks like in Reality 2, easy enough



but this is what it looks like in Reality 4 with identical settings
Image
asides from the richer darker color to the texture aside
The outer segment of the table looks horrible mangled
this is repeated on Every render it is in

whatever difference Reality 2 exports geometry into Luxrender does not do this


i even exported the OBJ of just the table to see if Reality 4 does infact treat the geometry the same and it does
Image
with out the textures but with the shading color you can still see the outer rim segment is still not smoothed

What and where i notice this being an issue is on broad flat polygons such as interior segments of scenery such is indoor spaces
some times you just get segments of wall that are just Blacked out and these errors in geometry just seem to make the scenery smaller and uneven looking to the eye.
Needless to say it's an undesirable effect it has on your final product.

I have however found how to fix this.
Image
See how much prettier it looks now that the curvature of the table and the unwanted lines that had made it look like a target reticle has been alleviated.

what you want to use is Micro-facets. I hear talk that Micro-facets only work on flat geometry and sine flat geometry seems to only be effected here
we are in luck

but it won't work without a displace map image
So i had created a 1000x1000 px 50% Grey JPG image ( RGB value is 128 )
I'm sure any size would do
and also set the strength and neg-pos numbers all to 0 just incase
Image
Setting the Subdivision to 100 for micro-facets to insure a good subdivision resulted in the offending surface to smooth out indefinitely

another example when testing this fix out was a Dance Dance Revolution arcade machine prop i bought and downloaded off TurboSquid
(because i'm a total nerd and love me some DDR)
Image
the issue is using reflective material such as metal or even mirror really screws with the feel of t he object when this error shows its ugly face
The issue is the faces of the polygons then are pointing at unintended directions causing the reflections to not line up with expectation
This leaves the object and the final product robbed of any wow factor because your brain picks up on this lack of detail and fixes it self into that uncanny valley observation

The dance pads is self are obvious, but you can see it on the cabin itself around and In the bass speaker segment.
The inclosure is more full and and the fake depth of it is been fixed.
If you notice the reflection of the right neon ring parallel ends that come out of the cabin is missing in the error prone image at the bottom of the casing. or even the reflection of the left neon ring makes a P shape in the back plating as opposed to a mirrored reflection.
Image

again this just robs the final images wow factor that luxrender is known for

I had other issues regarding gemstone props of it auto smoothing with disastrous results

I know this post was long, but with the lack of updates i figure maybe it was time to address this and or get some answers

or if anyone has been having issues with this and needed a fix, i got you covered

Thanks for you time"""

so objects with flat geometry seem to have this crazy problem of getting mangled on export
some get massive black segments or just look like they are bulging
when applying micro Facets subdivision to them
it goes away entirely

and another stranger example of this problem appeared when i was using a Null material for a volume


Image

i wanted to do some volume testing and I ended up with a weird black plane that showed up when set to Null
(i turned the volume off)
Image

Image
and i also get this when i return it to a glossy material
Its now not the whole face but half of it ( this is interesting, that whole face looks like its producing a shadow on the ground )

i don't know why it does this

if you subdivide it in lower levels like 1 or 2 it kinda makes the cube look bulky and not smooth
Image

So then I decided to download MeshLab because it can open the .ply files that Reality exports for Luxrender and i found something slightly interesting

I decided throw in a primitive cube into Daz for this test
Image
as you can see here its Just the cube, 6 faces, 8 vertices

and i had set only the IBL on with no image, just white and a camera to run the scene

Image
and ofcoruse this is what it produced when run though Reality 4

Image
and this run though Reality 2

Image
and this is what the cube looks like in MeshLab after the export
it is divided in Loop 1 level
which doesn't seem to be the problem

But check this out
On the right of the program lists the Vertices and faces
Image
"cube_8" is the ply exported by Reality 4
and "cube_cube_Default_2" is from Reality 2

but R4's cube has 18 vertices on the now 12 faces
while R2's cube has 24 vertices on 12 faces

i'm not sure where these vertices are coming from


8 to 24 makes more sense if each corner now has 3 vertices on top each other

but 8 to 18? that's 2.25 times more vertices
that's 2 per corner plus 2 just...Some where?

and ofcourse rendering the scene to 200SPP for a quick test of each scene file yielded this
Image
Reality 2

and then Reality 4
Image
But done with CPU only
Why does a single cube with an IBL render So differently and so Poorly between the two version of the plug in?
is it the vertices count of the cube?
does this exporting effect more complicated shapes like the Genesis models?
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Virgorival
 
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Re: Geometry exporting issue in Reality 4 vs Reality 2

Postby burnin » Wed Apr 18, 2018 6:34 am

Shading Issue: Smooth VS Flat/Sharp
In general (since i have no experience with Reality, DAZ or Poser)

Possible solutions could be:
- adding extra edge loops
- marking/keeping sharp edges (in Blender with Lux use Edge Split modifier, then setting it to your preference)
- setting/fixing normals
burnin
 
Posts: 287
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Re: Geometry exporting issue in Reality 4 vs Reality 2

Postby Virgorival » Wed Apr 18, 2018 6:45 am

burnin wrote:Shading Issue: Smooth VS Flat/Sharp
In general (since i have no experience with Reality, DAZ or Poser)

Possible solutions could be:
- adding extra edge loops
- marking/keeping sharp edges (in Blender with Lux use Edge Split modifier, then setting it to your preference)
- setting/fixing normals


I don't' think Daz it self has options like this, I don't think

But the issue is that this problem introduces itself in Reality 4

infact I imported that table prop into MeshLab and i'm finding the same thing
for the Reality 2 export, the .ply files have a considerable amount more vericices on the outer edge segment of the table, as well as other segments like the legs and even some surfaces that don't seem to be giving an issue such as the center segments

at this point i think i'm just Pointing this out
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Virgorival
 
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Re: Geometry exporting issue in Reality 4 vs Reality 2

Postby burnin » Wed Apr 18, 2018 12:28 pm

What you are describing with Reality 2 are extra edge loops. Those too (as mentioned) are a way of fixing the issue you're having.

This video might help you: Advanced Subsurf Modeling - Techniques to Avoid Pinching @ YouTube
Here the problem is explained in detail and solutions are offered. Techniques described can be applied in any DCC suite.
burnin
 
Posts: 287
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Re: Geometry exporting issue in Reality 4 vs Reality 2

Postby Virgorival » Thu Apr 19, 2018 1:26 am

burnin wrote:What you are describing with Reality 2 are extra edge loops. Those too (as mentioned) are a way of fixing the issue you're having.

This video might help you: Advanced Subsurf Modeling - Techniques to Avoid Pinching @ YouTube
Here the problem is explained in detail and solutions are offered. Techniques described can be applied in any DCC suite.


I'm not a modeler, while the video was super interesting, thanks for that

so basically the only way to fix it on my end would be to Manually edit the Scene files with the names of the ply files that R2 outputs

or open up each and every ply file in blender to manually edit the edge looping of every surface



i'm legit at a loss of words
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Virgorival
 
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