Lumion Support Center

Support for unlicensed users => Post here if you can't find your License Key => Topic started by: Morten on September 23, 2011, 11:01:53 am

Title: Moved: Pixelated reflections
Post by: Morten on September 23, 2011, 11:01:53 am
Moved from Frank's competition rendering thread:
http://lumion3d.com/forum/index.php?topic=2026.0 (http://lumion3d.com/forum/index.php?topic=2026.0)

By "grainy", do you mean pixelated?

(http://t0.gstatic.com/images?q=tbn:ANd9GcQ1Zio8qvECbaFx-tLr7RO_aAiYJXfLBXOPp9Ry_sfJTHKRGZDv)
Title: Moved: Pixelated reflections
Post by: SEVERINO on September 23, 2011, 12:00:52 pm
Hi Morten,
As this forum talking a lot of reflections, I want to send me what happens in curved crystals mainly
I get Fixel reflexes and the effect is very unpleasant.

Have a solution to implement in the current build 7 Sp2 64-bit?
Or at least some type of lighting, smoothing, and so on.?

I use max for models and FBX export as files.

Regards
Title: Moved: Pixelated reflections
Post by: Frank on September 23, 2011, 12:34:04 pm
By "grainy", do you mean pixelated?

Yes, pixelated. Excuse my bad english.
Title: Moved: Pixelated reflections
Post by: Morten on September 23, 2011, 12:42:57 pm
We are well aware of the fact that a blur setting is required for the cubemap reflection texture, but the pixelation on your rendering looks rather strange. Which graphics card did you render this image with? A Quadro card?

Here's what it's supposed to look like (rendered in 3-star mode and Settings -> "Low Mem" mode should be turned off):

Title: Moved: Pixelated reflections
Post by: Frank on September 23, 2011, 12:47:12 pm
@Morten
The pixelated reflections i described looked like the ones in the cube at your rendering.
Title: Moved: Pixelated reflections
Post by: Morten on September 23, 2011, 12:50:24 pm
Ok, so it's only Severino who is experiencing the weird artifacts so far...

We are obviously aware of the fact that the resolution of cubemap reflection texture and a lack of blur cause reflections to appear pixelated, but something else seems to be wrong on Severino's rendering.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 23, 2011, 11:37:29 pm
Thanks for confirming this, Daz - would you mind emailing me the Documents/LumionFree/Scene & Library files, so we can try to reproduce it? (morten [at] quest3d.com)
Title: Re: Moved: Pixelated reflections
Post by: SEVERINO on September 24, 2011, 10:54:51 am
Hello everyone,
I love challenges, if they are surmountable. Last night I started researching the problem of curved pixelated of my models and finally: THE SOLUTION. The problem lies in the smoothness of the model, ie before generating the export file, the model should be smoothed.

Here you have the result:

Thank you for your interest
Regards
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 24, 2011, 11:05:55 am
That's good news, Severino - thanks for your persistence :)

@Daz: Could you try to follow Severino's advice, ie weld any co-positional vertices and apply smoothing to the model before exporting it again please? As you probably know, you can re-load the model without losing the material settings if you follow the "Importing and Updating Settings" section in the Tips & Tricks thread:
http://lumion3d.com/forum/index.php?topic=638.0 (http://lumion3d.com/forum/index.php?topic=638.0)
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 24, 2011, 12:09:45 pm
Which application are you using if you don't mind me asking?
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 25, 2011, 03:02:26 pm
Hi Dazomatic, the way you are describing the rendering "sequence" as if "the last step is missing" is not how real-time 3D graphics work, but I can see why you jumped to that conclusion.

Anyway, I am not familiar with the DAE/FBX(?) export options in Ulead Cool3D, but it seems that the smoothing groups are not exported from Cool3D - or not imported correctly in Lumion.

To determine if the problem stems from Cool3D or the Lumion importer, there are two things you could do to help solve this problem:

A) Please post screenshots of the export settings in Cool3D, so that we can find out if any of the export file format(s) support smoothing groups.

B) If we fail to find a solution, you'll have to create a simple (smooth) sphere in Cool3D, export it to FBX/DAE (or whichever format you use) and send it to "Artur [at] quest3d.com" (Please note that we have got an Artur and an Arthur at Act-3D, so the way you spell that name is important :) ). Write "Missing smoothing groups in Cool3D" in the subject line and make sure you provide a link to this thread. He will be able to examine the exported data and determine if the smoothing group information is included in the file or not, ie, if the problem is caused by the Cool3D exporter or by the importer in Lumion.

If you would like to learn more about smoothing groups, please check out this video:

3D Studio's Max Smoothing Groups Tutorial (http://www.youtube.com/watch?v=-Iswm1xKtGs#ws)
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 25, 2011, 09:59:55 pm
One thing at a time, you're talking about two different things here :)

1) The problem with reflections that you and Severino reported:
As Severino mentioned, the problem was actually caused by the fact that his original model did not have any smoothing groups.

I've had a look at the .3ds files you uploaded earlier today and the same thing applies to your models: The models do not include smoothing groups in any of the 3D applications I've loaded your .3ds files in.

In other words, the problem is actually in Cool3D, so you'll have to explore the export options in that application to find out if a) you can turn on "Smoothing groups" in the .3ds export file dialogue window or b) export to another format, preferably FBX or DAE (Collada) files.

2) The shadows on the sink:
What you're seeing is normal behaviour in Lumion when shadows are almost parallel to a large surface. It doesn't matter which application the model was exported from, but what does matter is:

1) How detailed the model is, ie, how many polygons the curved surface consists of and...
2) How big the polygons are.

The sink in your example uses very few polygons (and is presumably big?) and as you can see on the rendering below, all you need to do to fix this is to add more detail to the curved segments (and/or scale it down if it's larger than usual?).

Title: Re: Moved: Pixelated reflections
Post by: Morten on September 26, 2011, 09:43:27 am
P.S. To make things more complicated, there's another factor which has an impact on the way shadows look on polygons that are almost parallel to the sun rays:
Weather -> Advanced Weather -> Shadow -> Clipping

Title: Re: Moved: Pixelated reflections
Post by: Morten on September 26, 2011, 11:09:25 am
The monkey head that they're using to demonstrate subdivisions is the famous Suzanne model from Blender:
http://www.blender.org/ (http://www.blender.org/)

Another (free) alternative is Sculptris:
http://www.pixologic.com/sculptris/ (http://www.pixologic.com/sculptris/)
Title: Re: Moved: Pixelated reflections
Post by: Frank on September 26, 2011, 11:23:47 am
Thanks for all that good hints, Morten!
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 26, 2011, 12:05:19 pm
its such a shame that a program that costs € 29.95,
 has no problem with smoothing curved meshes.
compared to another program costing € 1499.00. ...oh well .....que sera sera

If you're referring to Cool3D, the trick is to find a way to export smoothing groups (which the .3ds format should support) or alternatively, to export your models to another format, like FBX or DAE (Collada).

Adding more subdivisions to your surfaces is not going to help, until you find a way to export the smoothing groups. Almost all 3D modeling applications support smoothing groups, so it's surprising that you can't export them from Cool3D.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 26, 2011, 12:14:27 pm
Why don't you just import your model in Blender? It's free and includes a deform modifier which can pimp that logo up like there was no tomorrow :)
http://wiki.blender.org/index.php/Doc:2.5/Manual/Modifiers/Deform/Simple_Deform (http://wiki.blender.org/index.php/Doc:2.5/Manual/Modifiers/Deform/Simple_Deform)

(http://wiki.blender.org/uploads/thumb/7/75/Simple_deform_functions.png/600px-Simple_deform_functions.png)

Or just import the bent logo from Cool3D, then check that all vertices are welded, select all the faces of the mode, make sure that your model is smoothed (and we're talking about smooth shading here, not subdivision smoothing where you add more polygons) and finally export it to FBX or DAE format:
http://wiki.blender.org/index.php/Doc:2.5/Manual/Modeling/Meshes/Smoothing (http://wiki.blender.org/index.php/Doc:2.5/Manual/Modeling/Meshes/Smoothing)
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 26, 2011, 02:57:57 pm
By the way, I noticed that the mesh topology of the Warner Bros logo is messy in many places, so even after making sure that the model is smooth shaded the result is irregular reflections in Blender. The only proper solution is to create a model with clean mesh topology.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 26, 2011, 07:00:07 pm
This first image is from Blender (after I applied smooth shading to your sphere).

The second is from Lumion.

Cool3D uses non-standard mesh topology for some reason.
Title: Re: Moved: Pixelated reflections
Post by: peterm on September 27, 2011, 12:27:39 am
Morten, those last images, were the ones from Blender via Collada exporter or 3ds exporter?

These sort of smoothing issues can crop up when using some other 3d or CAD apps and exporting.

Here's some interesting base info about the old 3ds format, at Okino (http://www.okino.com/conv/exp_3ds.htm).  So it seems it depends on firstly the implementation of the exporter from the 3d app whether they actually convert any internal smoothing into exported smoothing groups and then how the receiving app makes use of smoothing groups to re-triangulate.

dazomatic; I see there's a new version? of Cool3D now released from Corel called MotionStudio 3D.  However, it looks like it still has the same limited exporters.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 27, 2011, 01:12:38 pm
As I said before, the mesh topology in the .3ds files from Cool3D is not following the standards of other 3D applications, so the results below will be identical in other 3d applications that rely on socalled vertex shading, such as Lumion, 3DS Max and SketchUp.

All you can do to reduce this problem is to try to crank up the detail level (polygons) in Cool3D as this will make the individual faces less noticeable.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 27, 2011, 01:28:04 pm
And here are the spheres with a Standard material in Lumion (exported from Blender in FBX format, but it looks the same in DAE format):
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 27, 2011, 01:40:56 pm
Morten, those last images, were the ones from Blender via Collada exporter or 3ds exporter?
...
These sort of smoothing issues can crop up when using some other 3d or CAD apps and exporting.

FBX/DAE work well when exporting models from Blender to Lumion, so the above tests were carried out using those file formats (the models look identical but on the screenshots I opted for the FBX files).

Quote from Okino:
Accurate vertex normals cannot be stored in the .3ds file. Instead "smoothing groups" are used so that the receiving program can recreate a (hopefully good) representation of the vertex normals.

Artur is in charge of importing in Lumion, and I don't know how he reconstructs the normals based on the smoothing group data in .3ds files. Based on my tests, his method is identical to those in other applications, such as Blender and 3DS Max.

If you are aware of other methods that may help resolve the non-standard mesh topology issues caused by the Cool3D exporter, please forward the information along with a link to this thread to artur [at] quest3d.com.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 27, 2011, 02:11:19 pm
@Dazomatic:
Lo and behold, I've noticed that if you import your Cool3D sphere in SketchUp 8 and run the 3rd party script CleanUp3, it will get rid of all the non-standard mesh topology on your sphere, so that the smoothing looks identical to a standard sphere from Blender/3DS Max/SketchUp:
http://forums.sketchucation.com/viewtopic.php?f=323&t=22920&p=193587 (http://forums.sketchucation.com/viewtopic.php?f=323&t=22920&p=193587)

After you've run the script, just add smoothing to the sphere since that data is still missing in the .3ds files from Cool3D: Simply double-click on the sphere, then right-click and crank up the "Soften edges" angle, run the CleanUp3 script and export as a Collada file. Alternatively, you can also set the smoothing angle in the CleanUp3 script (Smooth Edges by Angle).
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 27, 2011, 02:24:28 pm
Unfortunately, the topology of the Warner Bros logo is so messy that even CleanUp3 can't fix all of it. Whether this is "good enough" is a question only you can answer.
Title: Re: Moved: Pixelated reflections
Post by: Remko on September 27, 2011, 05:10:35 pm
The problem is the modeling package. It just generates crap meshes. You're probably better off with a package that generates proper meshes because I looked at some of the polygons and the topology is just ridiculous.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 27, 2011, 09:07:08 pm
As far as I can tell, BluffTitler DX9 doesn't actually import .3ds files, only .x files?

Can you give us a step-by-step description of how you get your model from Cool3D to BluffTitler?

Is it in fact via .x instead of .3ds??
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 27, 2011, 11:02:26 pm
The .3ds file format dates from 1990, and we don't recommend using this format due to its numerous shortcomings - think of it as a last resort once you've explored all other options:
http://en.wikipedia.org/wiki/.3ds#Shortcomings (http://en.wikipedia.org/wiki/.3ds#Shortcomings)

The .x file format (DirectX) on the other hand is a tried and tested format, and was used extensively for real-time 3D graphics over the past decade until the Collada and FBX formats became more mature.

So... Please upload the .x file version of the Warner Bros logo instead ;)

I would probably have found out earlier if only I could find a version of Cool3D that was compatible with Windows 7. Which version of Cool3D/Windows are you using?
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 28, 2011, 08:40:42 am
Please upload the .x file version of the Warner Bros logo.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 28, 2011, 12:38:01 pm
Yes, the .x version of the Warner Bros logo does not exhibit the smoothing artifacts that affects the .3ds file from Cool3D. In fact, it looks just like in BluffTitler.
Title: Re: Moved: Pixelated reflections
Post by: Morten on September 28, 2011, 07:11:39 pm
Yes, that's correct.

I imported your .x file in Quest3D (which is the program used to create Lumion), and it was just as smooth as in BluffTitler.

For now you'd need to convert the .x file to one of the supported formats though, e.g. DAE or FBX.