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General => Terragen Discussion => Topic started by: j meyer on July 03, 2015, 03:17:21 pm

Title: 3D Models and Terragen - Basics
Post by: j meyer on July 03, 2015, 03:17:21 pm
Hi y'all,
as the title suggests this thread is about some basics of modeling and/or preparing
3D models for use in TG and,maybe,related stuff.We'll see.

Let's start with creased or hard edges.
Hard edges are quite essential and necessary even for something totally rectangular
like a cube.
[attachimg=1]
Here is a wireframe screenie of the 96 poly cubes.
[attachimg=2]
As you can see in the above examples hard edges are important for the overall appearence
of your models especially in conjunction with TG's smooth normal feature,which is not
capable of setting one or even multiple smoothing angles.
Increasing the polycount helps to mitigate the ugly black stuff,but doesn't get rid of it.
The next example shows a UV-mapped and image textured object.
[attachimg=3]
The only difference between them are the hard eges only anything else is identical.
The normal smoothing sort of visually bulges up the sides of the brick.
One of the reasons you shouldn't model or use 4 sided tree trunks btw.
Another way to get the creased edges look would be to build your model from unwelded
planes.The outer borders of the planes are automatically treated as creased by most
render engines,as far as I know.This is a common technique that's pretty wide spread.
And one reason why it's not a good idea to simply subdivide downloaded meshes to
smooth them.
Since not every modeling software exports creases with it's obj files you should test
if your app does.In case it doesn't there is PoseRay.
There is more to say about export features or P-Ray and other stuff,maybe we can
address that later.

Ok,that's it for now.

Feel free to participate.


Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 04, 2015, 02:49:51 am
Good of you to start this, Jochen. I never paid any attention to creasing angles in LW, and only found it's workings in Poseray. So now I haul everything through Poseray (which works better than exporting from LW), and also found that I have to unweld all in LW first, or the maps get crooked. Then weld in Poseray and set the smoothing/creasing angle to an appropriate size. So, I now tend to make layers of shapes that need different angles, for beams, slighly rounded corners of buildings, or really smooth clothing, so I can smooth each layer differently, then export.
In Speedtree even a single flat leaf can have a 'smoothing' angle so it looks rounded, which is nice for grass, by the way.
Still, sometimes I have these black triangles in TG with a smooth surface such as an arm or head, even when smoothed at 180º in Poseray. Probably not enough polys, perhaps.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 04, 2015, 11:17:32 am
As for the black triangles I had cases were stuff like that showed up with
overlapping geometry as well.

Just to be clear with overlapping geometry I mean that a poly of one piece
of geometry is overlapping or somehow intersecting with another poly (or polys)
of the same piece.
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 04, 2015, 02:58:13 pm
Hi Dune,

Maybe you are referring to this kind of artifact ?
(https://www.thearender.com/cms/images/news/TerminatorArtifactTreatment.jpg)

Most of the time this problem can be fixed by offsetting the shadow,

Looks like Thea manage to fix that is a more sexy way.
It's a self shadow artifact, so as you said, increasing the poly count (+ subdivision level) reduce the problem a lot.
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on July 05, 2015, 12:01:17 am
Great thread you've started Jochen...PoseRay is more handy all the time, hadn't thought of this so thanks to you and Ulco....
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 05, 2015, 02:26:08 am
Indeed, Jochen, that sort of thing. Sometimes I'm a bit too keen to reduce polys perhaps (cutting off legs where trousers hide them, e.g.). Who is Thea?
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 05, 2015, 03:30:16 am

This probably Ulco :
https://www.3d.software/3d-rendering/thea-render/
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 06, 2015, 03:04:56 am
Thanks, Kadri. Didn't know that software.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 08, 2015, 03:23:12 pm
Well,since paq showed the jaggy shadow line in his post let's start with that.
Although I don't know of any shadow offsetting in TG I have to admit.

First image shows that jaggy shadow and in the shadow region some kind of
grid or raster.The latter is due to Gisd somehow.
[attachimg=1]
On the left a pretty low poly sphere 16 segments of 8 polys.The one the right
has 64 segments of 32 polys.As we can see both of the undesired effects are
mitigated by increasing the polycount.
Here a detail shot of the 64x32 sphere.
[attachimg=2]
The grid effect can be removed completely by turning of Gisd,but that's not always
a good idea,because you loose the Gisd allover of course.
The jaggy shadow line is something that can't be cured,just mitigated by increasing
the polycount.As soon as you zoom in or get closer it shows up again.Same goes for
that Gisd raster or AO facetting as I call it.
The closer the model the more polys are needed for rounded/curved surfaces.
If I got paq right other render engines might provide technical solutions for the jaggy
shadows.But that's beyond my experience and knowledge.
Here an example of that AO facetting on an actually used model.
[attach=3]
At least one more subdivision would be necessary here - with normals that is,without
you'd need some more,because of the then missing 'smooth normals' effect all edges
would render as hard/creased edges.More on that normal stuff later,hopefully.
More to come.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 08, 2015, 04:08:18 pm
Allow me point your attention at some other little querk I came across a while
ago.
So you have your sphere model and you want to texture it in TG with the help
of the mighty Power fractal and it's many features.Maybe something like that:
[attachimg=1]
You go on tweaking your PF and all of a sudden you see this:
[attachimg=2]
Oops!
That is what you get with 'distort normal' (warping tab) checked.
The only known solution is: don't use 'distort normal' when shading your
models and you don't like the effect.
You even get the effect with the fractal break up shader of a surface layer.Much more
subtle than shown here.Sometimes it looks like a visible seam line or so.
I have a rust shader that makes use of this effect.So it can be even useful at times. :)

Here is the official statement from back then:
http://www.planetside.co.uk/forums/index.php/topic,11850.msg120861.html#msg120861
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 08, 2015, 04:22:56 pm

About the jaggy shadow line, it only goes away when you uncheck "Do ray traced shadows" in the "Extra" tab in the Render node.
I searched to find more about it and how much it changes anything but could not find much.
Maybe it can be used in certain circumstances, i don't know.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 08, 2015, 05:07:19 pm
And one more.

Let's say you have a little low poly model that is not UV-mapped,but set up to be
procedurally shaded in TG.So,no UV's just a few parts to put different materials on.
Maybe a heli like this:
[attachimg=1]

And now you want to put some dirt or color variation right on top of what you already
have.To achieve that you might choose a setup like so:
[attachimg=2]

With that kind of setup you could expect to get something close to that:
[attachimg=3]

And in many cases your expections are matched by the result,but sometimes you
have to be prepared to see this:
[attachimg=4]
Oops,wtf...?

There are 2 solutions I'm aware of for this one.
The first one is to pipe the Power fractal through a Transform shader with 'use
world space' checked.Nice and easy.
The second one is to find the reason for that and to fix the model accordingly.
As far as I could find out it is caused by a messy vertex order.You need a modeler
that's capable of optimizing the vertex order to fix that.Or you could retopologize
that part in one way or the other.
In case you know other methods to fix the vertex order,please share with us.

While preparing this I separated the hull part to use that alone for the images
in this post.And to my surprise it looked different,still not correct,but definitely
different.
[attachimg=5]
So if your model is a single part model it might look like this rather than like in
the image before.

That's it for this time.

Any suggestions as to what else should go into this thread?
The stuff that came up in Michael's thread is on my list already.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 09, 2015, 01:39:09 am
Thanks again, Jochen. I found that no UV map often gives a very strange preview of the object, like it's all flat. Though I never rendered any without UV map. So I always UV map parts that don't need it, any mapping will do.
I often can't really get the angle right for smoothing the normals. In Poseray, standard is 35º, in LW 89.9º. For people and clothing I set it at 180º in Poseray, for say a wall with a window that has one extra poly to smooth the angle (so the angle is 45º instead of 90º), it should be around 45º I'd say, less will give a hard edge, but more often gives a strange shadow on the whole wall also. Never got my head around that exactly.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 09, 2015, 12:53:14 pm
Quote from: Kadri on July 08, 2015, 04:22:56 pm

About the jaggy shadow line, it only goes away when you uncheck "Do ray traced shadows" in the "Extra" tab in the Render node.
I searched to find more about it and how much it changes anything but could not find much.
Maybe it can be used in certain circumstances, i don't know.


Thanks Kadri.
Here is the illustration
[attachimg=1]
Decide for yourself everyone.
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on July 09, 2015, 01:42:02 pm
Interesting....Great thread Jochen.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 09, 2015, 01:48:41 pm
Ulco it would be nice if you could mail me a simple example of such a no UV obj
with a strange preview so I could look into it.

As for the smoothing thing:
1.generally - as far as I know you don't smooth normals,but you set a creasing angle
which determines if an edge is considered to be soft or sharp by the render engine.So
that the "smooth normals" effect/feature of the render engine can take that into account
Otherwise it would constantly try to smooth out anything.(See first post)

To avoid further confusion about that - at least in this thread - please let us all try
to use the same terms.

2.Yeah,I also have problems to understand the way PoseRay handles or better defines
the angles.Pretty confusing.Still trying to find out though.
3.Unless you need sharp edges on your humans or clothes you should not recalculate the
normals at all.It's really only necessary in cases where hard (sharp,creased) edges are
needed/wanted.(or if the normals are missing of course)
As for the 45° angle it should work with a setting of 40 -45° anything above and you
see these "shadows".That's the same as the ugly black stuff in the first post.
It just looks a bit different in P-ray.You can use that as an indicator wether your edges
are creased correctly or not.
You said you see that effect ( the "shadows") also with settings below.
There seems to be some change in P-rays behaviour at 35° as it creases angles greater
than 90° with that setting too.
Have to investigate that some more.
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 09, 2015, 02:31:07 pm
Hello,

I'm not sure I will help about the confusion here, my english is very basic.

The problem here has nothing to do with angle based smoothing .. whatever the way you split your normal (manually, angle based), self raytrace shadow artifact will allways happens until something is fixed in the renderer itself.

Gouraud shading will smooth the normals to make a polymesh looking smooth, but raytrace shadow use the 'real' geometry to compute the rays. As a result gouraund shading and raytrace self-shadow dont match.
You can easily see why if you render the mesh without any smoothing.

As I said previously some engine fixed this problem by introduce a bias either by light, or by object. This bias will cut ray hit point within the distance define by the user (bias) and fixed the glitch.
I prefer the 'by object' method because the bias needed can be very different, big utlra low mesh need a much bigger 'fix' distance than utlra hires mesh.

This bias will also shrink the shadow of every object in the scene, that's why a 'by object' solution seems better.

My guess is that there is allready a minimal global bias distance in Terragen, to deal with doubled sided geometry, but maybe the bias is not big enough to deal with very low geometry like posted here.




Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 10, 2015, 02:19:29 am
So maybe Matt should introduce a bias slider per object?

I'll see if I still have an unmapped object, or I'll fix one. Problem with my workflow is that if I set merge points in LW, I see torn edges in the maps in Poseray. So I unweld everything in LW and only weld in Poseray. Then I have to recalculate normals.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 10, 2015, 12:49:10 pm
paq - too technical for me,but thanks anyway.

Ulco - did Kadri's post with the P-ray quote help you?
I did some more experiments last night and think I understand how to make it
work for me at least.Ran out of time before I could render some examples.
Hopefully tomorrow,if that's still wanted.
Do you do your UV mapping in LW before you merge points? If so,chances are
good that that messes up your UVs and thus the torn edges.As far as I know
you can split/cut parts after UVing,but welding pieces afterwards requires
some repair work.


Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 10, 2015, 01:30:33 pm
Hey Dune,

I'm still not really sure why you use PoseRay ? To have hard/smooth edge working in Terragen ?
Looks like they are a couple of option in the LW-modeler .obj exporter :

(http://forums.newtek.com/attachment.php?attachmentid=95079&d=1305103380)

The most important one seems : obj write normals, that should give you a 100% identical shading result between LW and Terragen.
If 'merge point' also merge uv coordonate, then don't toggle this one, as it will indeed broken your uv's layout.

Keep in mind that .obj only support one uv map, so check if uv's are not split into multiple channel, and if it's the case merge them all in one channel.

I havn't use lw since years, but if I remember right, the LW-Layout also get multiple exporter options, that use different .dll from the LW-Modeler.
Maybe you could also give .fbx a try (from Layout) ?
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 10, 2015, 01:41:00 pm
Thanks paq,that is really helpful!
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 10, 2015, 01:43:36 pm
^^
By chance do you know the Maya equivalent to this? Having trouble determining why poseray works but not Maya. And frankly it would be really strange that poseray does something Maya can't.
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 10, 2015, 04:16:48 pm
hello,
Just to be sure, I did a nasty test to check Terragen import capacity, and it works perfectly, at least the .obj one .
The mesh was generated with a Nurbs software (MOI), so it's a collection of nasty micro triangle and quad's.

Custom vertex normal data prevent ugly shading resuly, and Terragen use the data perfectly.

Modo export .obj fine too out of the box.
Maya, I don't know, what are the options available ?

Maybe you have to compute and store the normals before exporting ? (looks like there is a lock normal feature ? but I'm not sure if it's the way to go)
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 10, 2015, 04:59:32 pm

One OBJ file to rule them all is it not as it looks.
There shouldn't be so much differences in different OBJ export-imports but not much to do as it looks...
If the technical side comes so much in front i begin to not like what i do.

Paq, that OBJ loader image looks good indeed.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 10, 2015, 05:05:18 pm

Paq, i remember that in one or more verions in the past in Lightwave the OBJ export was bad-brocken.
Since then i use mostly Poseray to convert LWO files.It works now probably better.
Not sure if this is one of the reasons Ulco uses Poseray too.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 11, 2015, 02:42:54 am
I am very grateful for all your input guys, very helpful indeed. Though I didn't get a chance to read through the Poseray manual, I saved it as pdf, so will later.
@paq: the problem might be that I still work in LW 9, and that doesn't export obj's set up in layers, e.g. Only one layer exports. If I put it all on one layer it works though. I still have to experiment more, but I am kind of glued to my workflow, and it takes time to deviate and experiment. LW 9 doesn't have such a fancy exporter menu, it just runs. So I guess, Kadri is right. And yes, that's why I use P.
@Jochen: In LW I make a part, like a beam, and UV it. If I want specific parts to be oriented differently, I select the polys, cut and paste, or unweld, and move it around, or remap that part of the part. Then what I usually do is merge points.
But I also cut of parts of finished beams off in the normal viewports, and paste them to another layer temporarily, and move them around for additional beams (under eaves for instance), so I don't have to UVmap them separately. Then I select them randomly or one by one and move them around or rotate 180º in UV space, so they show different parts of one texuremap.
Probably not the right way, as exporting this lot often gets the UV map torn.
Anyway, I haven't been modeling that long, so it's still a big learning process for me, and thanks again for all the info guys!
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 11, 2015, 09:01:51 am
QuoteMaybe you have to compute and store the normals before exporting ?

Yes, this may be something to go after. I read that normals have to be "applied", or rather any changes do. But there was no instruction, just the statement. So I have to search this out tonight.

my feeling is that somewhere in this is the answer to what poser is doing and what the other soft is doing automatically.

Where Maya is concerned, it feels to me that there are many many tools but no automation. For automation they give you python and mell, which you can build your own auto tools with. But I can write only very little in mell, and don't know any python, so I have to find all the manual ways of doing everything, or find scripts write by others.
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 11, 2015, 11:41:32 am
Hi Dune,

Might be a little bit tricky to find a lw 9 trial, so I'm affraid I can't help you that much for now.
'The merge layer before export' sounds familiar to me from the old days, but I'm sure there are script and plugins that can handle this ... maybe even a native 'flatten' layer' command in LW-M ?

As for the .obj export options, they are in the global options of LW-M (so it's not something that pop at export time). Try to type 'o' in the modeler ?
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 11, 2015, 03:53:59 pm
Ulco you can access poseRay's manual form inside the app and in the folder where
the program's files are is a clickable htm file to read in your browser.
Paq is right LW should have global export options.That would have been my next
recommendation,too.

I can't say that the manual is right about how it works.Maybe it was intended to do
so,but practice shows something else.But,of course I might be too stupid again.
That's another thing I like about Wings3D you don't have to care about creasing
angles or how they are defined by the programmers.You want an edge to be hard
you set it to be hard and that's it.That way you can crease as many different angles
as you like,all in one single piece object,no problem.

Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 11, 2015, 04:12:39 pm
There are three approaches to low poly or mid poly modeling for TG I know of.

The first one would be to use hard/creased edges only.

The second hard edges in conjunction with a bevel.That catches a bit of light
and mitigates the sharp look of the first.

Third is no hard edges at all.Instead you have sort of rounded off corners/edges.
Take a look and you'll hopefully see what's meant.

Hard edges
[attachimg=1]

Bevel and hard edges
[attachimg=2]

Soft/uncreased edges
[attachimg=3]

That's how they look in TG
[attachimg=4]

to be continued in the next post


Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 11, 2015, 04:40:36 pm
These approaches are not really suited for close ups,but to see the differences
more clearly here are some close ups.

Hard edges
[attachimg=1]

Bevel and hard edges
[attachimg=2]

Soft/uncreased edges
[attachimg=3]

And with 'real' displacement in TG (Ray trace objects unchecked)
[attachimg=4]

Hard edges and 'real' displacement don't play together well.

If I'd want to apply 'real' displacement I'd use high poly meshes without any
creasing for best results.But since TG's ray tracer doesn't render the shadows
of the displaced object,only the shadows of the undisplaced object the
displacement should be kept rather moderate.

In case you want to know how to model the soft/uncreased edges cube I can
illustrate that,too.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 12, 2015, 02:17:56 am
Jochen: the last edge sample; are the extra 'edges' besides the angled corner polys needed for calculation of the angle softness, the corner normal? I mean, in the second sample, you have one bevel poly, in the third there are two, but also the adjacent polys, which are not angled but in line with the sides. I sometimes use the one bevel for a low poly distant 'soft edge', but the double edge for more close-up work, but not the adjacent poly's. Simply said, is that good or bad?
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 12, 2015, 03:00:39 am
So what was that all about normals then?
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 12, 2015, 12:05:12 pm
Ulco - the extra edge loops in the 3rd example are needed indeed as the faces
around the big center polygon all have a slight angle relative to that center poly.
Of course you could get away with one or two loops less,but the transition would
be harsher,more noticeable.
I'll prepare some more illustrations to show.


Michael - could you please be a bit more specific,what exactly you are refering to?
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 12, 2015, 04:53:38 pm
Quote from: TheBadger on July 12, 2015, 03:00:39 am
So what was that all about normals then?


Quotecould you please be a bit more specific,what exactly you are refering to?


Well, if you take the model I sent you and you open it any modeler than it looks fine. If you send it from any other modeler to TG, it works fine. But from Maya it breaks. What was partly determined is that the normals had to be smoothed, not the geo. Some programs like Modo for one do this auto, but not maya.

This is in reference to the Architecture thread in image sharing. I think the next part of your thread here should cover normals, because that has turned out to be the confusing part for me.
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 13, 2015, 11:40:56 am
Hi Badger,

I did some really quick test using maya 2015 sp2, and I don't see really problem to export normals.
Have you tried to apply an 'average normal' command before exporting to avoid hard edges and thus displacement gap ?

Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 13, 2015, 02:25:16 pm
Hi paq,

Can you give the steps to "apply normals", please. This is the part I can't find...

I found how to smooth normals, but not how to apply it, only several references that I should apply it but never any steps how to do it. Normals are for some reason, not much discussed when I search for some reason.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 13, 2015, 03:09:09 pm
Michael,I'll better wait to see if you two can figure it out to your liking.
Maybe my view won't be needed anymore then.



Noticed a little mistake in my above posts on the 3 approaches.
In the third example (soft rounded edges) I didn't remove all edge loops
that are possible to delete without affecting the rounding.Forgot one pair
per axis.
Sorry,what can I say,I was young and needed the money....errh,
oops,wrong phrase,well then,it was late and I was tired. ;)
Or I'm just the usual scatterbrain.

Here is the correct wireframe and polycount
[attachimg=1]

The result when rendered in TG is visually the same as before.
Just the polycount is not 486 ,but now 294.

The announced illustrations will follow in the next posts.
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on July 13, 2015, 03:16:52 pm
Quote from: j meyer on July 13, 2015, 03:09:09 pm

Sorry,what can I say,I was young and needed the money....errh,
oops,wrong phrase,well then,it was late and I was tired. ;)
Or I'm just the usual scatterbrain.


hee hee hee
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 13, 2015, 03:55:57 pm
[attachimg=1]
Some random geometry, with a mix of hard/soft edge.
If you apply a displacement on this kind of mesh, every hard edges will create a gap.

[attachimg=2]
You can average the normals in the 'normal' menu.

[attachimg=3]
Now the mesh should be gap proof ... the global shading might look a little bit weird too.

[attachimg=4]
These are the options for the .obj exporter ... seems to work fine ... but I never used maya myself.
Looks like a common song on every forum is 'first, delete you construction history' ... might help too :)

[attachimg=5]
This is mostly the kind of topology you need to control the overall shading without using edge crease (break normals) in your model.
It's in fact very close to subdivision modeling topology, where you try to keep tension by duplicating edges .

It's very time consuming, but very useful if you want to prevent displacement artifact ...

hope it helps.
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 13, 2015, 04:05:15 pm
Thank you.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 13, 2015, 04:25:55 pm
Cool! Thanks paq!

Now for some more pics and stuff.
You will find me using the term smooth subdivision here.The terminology can
vari from one modeling app to the other.That's why I want to show you the
difference between subdivision and smooth subdivision.

[attachimg=1]

Next are some steps to show how you can get the kind of topology on your
cube like shown earlier in this thread.Like on the corrected version of the soft
rounded cube to be precise.

[attachimg=2]

An edge loop is a closed ring of edges btw.
As you can see the added edge loops (2. + 3.in the image) prevent the cube
from that shrinking effect when smooth subdividing,shown in the first image
of this post.
Since I don't know the 'official' name for these additional loops I called them
stopping loops and will refer to them as such in this thread.
On complex shapes installing these loops can get tricky,but they are a good
way of keeping the edges of a model from being smoothed too much.

To be continued in the next post



Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on July 13, 2015, 04:28:19 pm
Nice sum up of the problem paq.
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on July 13, 2015, 04:31:08 pm
keep em coming Jochen...and thanks
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 13, 2015, 04:45:35 pm
Now that you have your 2x smooth subdivided cube you can start to reduce the
polycount,if needed/desired.
There is an area where the polys are perfectly even (or in other words where
adjacent faces have an angle of 0° or !80° from one to the other) on each
of the cube's sides.
They are all in the same plane,so you can delete all edge loops within these
areas without altering the result of the smoothing.

The areas
[attachimg=1]

and the reduced result
[attachimg=2]

You have seen the reduced result rendered in TG some posts above already.
But you'll see it again in my next post where I'll show some different versions
of the cube for you to compare.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 13, 2015, 05:26:14 pm
Here are a few different versions of the cube so you can have a look and then
maybe decide for youself,if it suits your needs or as Ulco put it,if it's good or bad.
Most likely it will depend on your project(s) anway.

The illustrations show both rendered result in TG and a wireframe,so you know
what is what.
Smooth subdivided 1x or 2x means after having installed the stopping loops,
just to remind you.

#1
[attachimg=1]

#2
[attachimg=2]

#3
[attachimg=3]

#4
[attachimg=4]

#5
[attachimg=5]

As stated above it will most likely depend on your project and your pretensions
what is tolerable and what is not.

And again that's all for now.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 14, 2015, 03:05:58 am
This is a great thread, Jochen. Thanks very much. I am still relatively new to modeling, so it's an eye opener. It would probably go too far to explain how to create edge loops (I do know multishift) and (easily) delete unwanted subdivision in LW?
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 14, 2015, 12:52:46 pm
Unfortunately I have no personal experience with LW and a quick look at
the LW7 manual didn't really help as LW seems to have a pretty different
modeling.I could not find any edge tools.Seems LW does the modeling
just by manipulating points and faces.(and curves etc)

I could only show exact steps for wings3d,if you think that'd be of help to you.

Maybe a long term LW user can help us out here.Please.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 14, 2015, 01:26:16 pm

Have a look at this video for example Ulco.
There are different ways and some plugins for edge loops. He mentioned some plugins too in the video.

https://www.youtube.com/watch?v=ipFEI3R_rDM

One way for getting rid of unwanted surfaces is selecting the surfaces and using the "Merge Polys" command in the "Detail" tab in modeler in polygon mode.


Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 15, 2015, 02:00:00 am
Thanks guys. I don't want to take over this thread, but thanks to you I discovered the edge bevel. And more after seeing the tut...
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 15, 2015, 12:20:05 pm
Thanks Kadri. :)

No problem Ulco this thread is meant for stuff like that.



Title: Re: 3D Models and Terragen - Basics
Post by: Oshyan on July 15, 2015, 09:02:50 pm
This is a really useful thread. But I think the post-question-response(s)-repeat forum discussion model is not a good way to present such information. It means the information is harder to find - it must be culled out from amongst other responses - and that incorrect or outdated information is harder to avoid/eliminate/update. A Wiki approach is ideal to solve this kind of need for potentially collaborative documentation/information and ongoing updates and improvements. So I would strongly suggest creating a Wiki page in the user-generated content area of the Planetside wiki to hold the "final" version of this info. For this, and especially in the future, I think it may be best to start the Wiki page, then start a forum thread to discuss it, but keep all informational and content posts in the Wiki, with only discussion, Q&A, etc. here in the forums. Note that there is also a discussion method in the wiki that could be used, but I imagine most people would prefer to do it here (this forum is a lot more full-featured and easier to use for discussion, for one thing).

Wiki is here: http://planetside.co.uk/wiki/
And is open and freely editable by any forum member. Just use your forum login credentials.

- Oshyan
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on July 16, 2015, 02:28:05 am
Quote from: Oshyan on July 15, 2015, 09:02:50 pm
This is a really useful thread. But I think the post-question-response(s)-repeat forum discussion model is not a good way to present such information. It means the information is harder to find - it must be culled out from amongst other responses - and that incorrect or outdated information is harder to avoid/eliminate/update. A Wiki approach is ideal to solve this kind of need for potentially collaborative documentation/information and ongoing updates and improvements. So I would strongly suggest creating a Wiki page in the user-generated content area of the Planetside wiki to hold the "final" version of this info. For this, and especially in the future, I think it may be best to start the Wiki page, then start a forum thread to discuss it, but keep all informational and content posts in the Wiki, with only discussion, Q&A, etc. here in the forums. Note that there is also a discussion method in the wiki that could be used, but I imagine most people would prefer to do it here (this forum is a lot more full-featured and easier to use for discussion, for one thing).

Wiki is here: http://planetside.co.uk/wiki/
And is open and freely editable by any forum member. Just use your forum login credentials.

- Oshyan



great idea
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 16, 2015, 02:01:07 pm
I've put it here deliberately.From my point of view it should be a dialogue.
And I think we should collect some more related stuff and have people
asking their questions in relation to models in TG/modeling for TG first.
If only to find out what kind of info may be useful especially for the less
experienced for example.
In case someone wants to put it in the wiki later on we should be able to
find a solution.


Btw,how about that stuff about models in the Preview window (with and without
normals and normals flipped) posted in the support forum a while ago?
Should I post that into this thread,too?
What do you guys think?
Title: Re: 3D Models and Terragen - Basics
Post by: Hetzen on July 16, 2015, 04:32:25 pm
A quick point on smoothing groups. It's not about smoothing the geometry, it's about smoothing how light works on the surface.

I've only ever modeled in Max and it's not really one of my disciplines. Most 3d software uses similar techniques just named slightly differently.

In Max, you have Smoothing groups, which allow you to apply smoothing across the geometry. The reason there are groups is so that if you want a curved surface to have a hard edge against another curved surface (like two sides of a clam shape where the lip comes to a hard edge), in Max you can apply the top half with smoothing group 1 and the lower half as smoothing group 2. This would then smooth the surface of everything within the group and not try and smooth around the desired hard edge.

A sphere should only have one smoothing group as there are no edges to differentiate.

What smoothing groups don't solve is how the outside edge of the object curves. This will always be faceted by the number of vertices you have in that object's plane of curvature.

As an example, a low poly sphere with 1 smoothing group will look smooth in the centre but hard edged at the sides as there is not enough vertices to define the curve around the objects edge.

Paq's post with the TV type object shows what happens when the object has only one smoothing group. The light interacts weirdly, because it's trying to smooth all of the surfaces together, when in fact there are various combinations of right angles to consider too.

Jochen has shown what you need to do to get a curved edge very clearly, you have to bevel it a few times and apply one smoothing group to the whole cube. This is really important with displacement in any program.

Back to Paq's TV, to get a correct effect he will need to bevel where he wants rounded corners and change the smoothing group number of the polygons where he wants them to have their own unique smoothing. So for example, the large beveled cube would have smoothing group 1 applied, the sides of the first extrusion (4 of them) would each have unique smoothing group numbers so that the right angle is maintained when shaded. The next level of extrusion would have another 4 if he wants to maintain the hard edge and so on.

Most programs have an auto smooth function within the polygon/mesh properties which does most of the work for you. You just set the threshold angle and let it do it's business. But you more often than not need to get into the mesh and add you own smoothing groups to certain surfaces that you want to distinguish between that may not fall within the threshold you've set.
Title: Re: 3D Models and Terragen - Basics
Post by: Oshyan on July 16, 2015, 08:31:56 pm
Having a dialog (like this one) does not have to be "instead of" a wiki page, it can (and should be) *in addition to* a wiki page. This thread is potentially very useful and will get lost fairly quickly once people stop discussing it. Yes, we could Sticky it, but then we have a potentially long (already somewhat long) discussion thread that people have to read through to get what would probably be 1 or 2 pages of real, useful information, and they have to sift through questions, experiments, and potentially non-ideal solutions to get the best info. That's the value of having a wiki page: you can present distilled, "best practice" information and it never gets lost.

- Oshyan
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 16, 2015, 09:18:02 pm
Since there are other directions basic modeling can take you, such as sculpting, I wanted to point out that in most cases you would not want to subdivide when taking your object to sculpt.

With the example of the cube(s) from this thread, you would make the shape and scale, but not subdivide until you got to your sculpting soft. The reason is that you want very even and uniform polygons. Wen you start removing edges and verts as in the examples on this thread, you will alter the normal effect of subdividing further. The result will be uneven distribution of polygons over the shapes like a cube.

Now when bringing your sculpt back to the original model to bake, you more than likely will want to subdivide, this will give the maps better results on your base model. But it is a case by case thing. Trial and error is a necessary part of it because every model is going to be different. The point is that the shapes/forms to take from your modeler to sculpt on be clean.

the idea of creating polygons by subdividing (smoothing) and then removing unneeded polygons (in Maya- the "remove edge and vert" command) Is a proven modeling workflow for sure. That is how I learned. With "digitalTutors, for example, this method is used in maya and pretty much all the other software that allow for it (which I think is basically all modelers).

I realize that going into sculpting takes us into more complex modeling (not exactly the "basics"). But I learned this lesson the hard way, and only want to point out that as a someone begins a modeling project, you want to be sure of how you plan to start and finish. There is a definite process and order of doing things in 3D modeling. And I know from pain, that you cannot always get good results in a sculpt from a base model that you have already done too much work on.



Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 16, 2015, 09:20:21 pm
Hello,

Quote from: Hetzen on July 16, 2015, 04:32:25 pm

Back to Paq's TV, to get a correct effect he will need to bevel where he wants rounded corners and change the smoothing group number of the polygons where he wants them to have their own unique smoothing. So for example, the large beveled cube would have smoothing group 1 applied, the sides of the first extrusion (4 of them) would each have unique smoothing group numbers so that the right angle is maintained when shaded. The next level of extrusion would have another 4 if he wants to maintain the hard edge and so on.


(http://www.planetside.co.uk/forums/index.php?action=dlattach;topic=20209.0;attach=58423;image)
On this example, if you are speaking in 3dsmax term, there is only one single group for the whole object. There is no need to break the normals, the extra edges are there to keep the shading 'right' or acceptable.



[attachimg=1]

Technically it's not really a bevel either, but more an edge shift, in both direction, for every edges you want to keep 'sharp' ...
in the same way you would prepare the mesh for a Catmull Clark surface subdivision.

In many package, bevel = rounded edge, fillet, or even chamfer. This commands can quickly add lots of complexity into the model,
and depending of the settings, it might even erase the initial edge position.

By shifting edges, or sliding them (again, it depends of the DCC software used), you keep the initial edge in place.
It makes further editing much more simple.

(That having said, you can do this modeling task on multiple edges at once in Modo, using the Bevel command  ::) , with 'sharp corner' + 'square edge shape' option activated)
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 17, 2015, 12:13:36 am

Quote from: Hetzen on July 16, 2015, 04:32:25 pm
A quick point on smoothing groups. It's not about smoothing the geometry, it's about smoothing how light works on the surface.
...


Yes it is true for other programs.
But when you use displacement with the micropoly render in Terragen (ray trace OFF) it handles the geometry different.
So in Terragen it actually is kinda smoothing (holding the edges together) the geometry.

Matt said this:
"If the object doesn't have normals, Terragen defaults to using the face normals. These are usually discontinuous from face to face. If two neighbouring faces are displaced along a different normal then the object splits apart at the shared edge (Terragen doesn't fill in the gaps).

If the object has normals (vertex normals) and the normals are the same for each shared vertex (they are "smooth"), the normals at the face edges will be the same for all neighbouring faces, so displacement doesn't cause them the split separate.
"

From here:
http://www.planetside.co.uk/forums/index.php/topic,19431.msg190793.html#msg190793

With smooth normals practically it ends like that a very basic cube with 6 faces looks like it is heavily subdivided like in another program.
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 27, 2015, 02:18:52 am
Because I am fixing some issues, Ill post this here as it is related to basics.

Non-planar Faces in TG.

In maya where I am modeling currently, Non-planar Faces are not a problem. Mostly you cannot even see it, but when you smooth normals, they can become very ugly.
The following is a description of Non-planar Faces:
     
QuoteNon-planar faces are polygons with at least four vertices that do not lie on the same plane. In other words the vertices of a Non-planar face no longer form a flat surface in 3d space. Non-planar faces are not necessarily bad; in fact Maya doesn't care at all. Objects with non-planar faces can be smoothed, rendered and all polygonal tools should still work fine. When modeling for a game engine Non-planar faces may cause problems, but luckily they can be fixed without any problems. Cleanup will find and highlight all non-planar faces and if told to cleanup it will triangulate all non-planar faces. In this case triangulation is the easiest method to fix non-planar faces since three sided polygons (also known as trigons) always form a plane in 3d space. If you are keen about keeping your model in four sided polygons (also known as quads) you will have to clean up the geometry manually. The best way to go about it is to use the orthographic views (front, side, top, etc.)

     
What I wanted to point out, is that non-planar faces will show as problematic in TG as well if normals have been averaged/smoothed. It appears like the renderer does not know what to do with the light, and makes those faces much darker or much brighter than the surrounding faces. The only fix is to go into the modeler and delete those faces, and replace them with planar faces (in maya--> select one edge and double click and delete---> mesh--->"fill hole")

At this moment I am not sure what happens to the normals when you delete a face and replace it.

Anyway, A lesson I learned, Model very very carefully even if you don't think you need to. There is always something waiting to kick you in the balls.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 27, 2015, 10:21:14 am

That was why i mentioned the ngons before Michael.They can be problematic in nearly in all programs.
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 27, 2015, 11:13:35 am
You mean in addition to quads right, not that it can't happen with quads? Anyway at least for me, Ngons are much worse problem in TG. entire areas will not render at all with ngons, so whole sections of models missing. At least that is what happened when I first had that problem in TG2.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 27, 2015, 11:43:59 am

You can have problems even with quads or trigons using in different programs and with normals etc.

If i remember correctly the only place you will have no problem with ngons are  flat surfaces,not sure.
And it depends on the kind of surface angle,normal etc. So it works sometimes without a problem even in Terragen.

But ngons are so bad it is even meaningless to search for a solution for this if you ask me.
The safest way is whatever you model try to don't use ngons.

Others might have more knowledge about this.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 27, 2015, 01:01:12 pm
Ngons are a problem,most definitely.Even on flat surfaces.

Non planar faces can be problematic indeed in conjunction with 'smooth normals'.
That's what I was refering to in Michaels thread in my reply to Matt's post lately.
They - non planar faces - are hard to avoid when sculpting.

Going to do that shader related stuff tonight,maybe I'll add an illustration for the
non planar faces as well.
Title: Re: 3D Models and Terragen - Basics
Post by: TheBadger on July 27, 2015, 09:16:45 pm
Well if at some point you do break all this down into a wiki entry of some kind. there should be a section/paragraph on things not to do/things that never work. So Ngons and how TG just can't cope with the trauma, and some of the other things that are fresh in the threads right now. Just saying. ;D
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 27, 2015, 09:29:24 pm

J meyer this for example worked without a problem :


[attachimg=1]


With flat surfaces i did mean this kind of examples.
But when 1 or more vertices changes position (in this example in the Y axis for example) for whatever reason, it can get problematic very fast.
I haven't tested it with different normal angles.So even it works like above it could be problematic with different normal settings as you said.
I would subdivide it before serious use and get rid of any ngons.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 28, 2015, 04:23:34 am
Here's a short informative link: http://blog.digitaltutors.com/ngons-triangles-bad/ (http://blog.digitaltutors.com/ngons-triangles-bad/)  I didn't realize ngons and triangles should be avoided (too new to modeling  ;)). When hauling through Poseray, it's automatically triangulated, I think.
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 28, 2015, 11:20:39 am
Hello,

Well the blog is talking about subdivision surface modeling. If you prepare assets for Terragen, you don't really have to care.

When working with subdivision modeling, you actually prepare a 'cage' model, that will be subdivide and smooth out using (most of the time) a 'catmull clark subdivision' method.
And this subdivision function gives a better visual result when dealing with quads, or at least predominant quad models.

But not every models have to be made that way, if you model a little architectural piece for you environment, you can just mix poly, tries, ngons ... it doesn't matter.
Behind the scene, there is only triangles anyway ... quads and ngons are just 'helper' for modeling, because it's easier to deal with.

For terragen, you only have to triangulate ngons before export. You can leave quad as quad, or you can triangulate everything.
Just save a 'working' model too in you modeling package (using native format, because .obj sucks :P), with the original topology for further editing.

Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 28, 2015, 01:06:52 pm
Kadri I can't see what you have done there without seeing at least a wireframe.
Maybe there are exceptions.


Modeling in quads is the way to go,although an occasional triangle won't hurt.
Ngons are to avoid.
As Matt pointed out earlier elsewhere on these forums TG triangulates any
imported model anyway and you as a modeler should only triangulate your
(finished) model if you prefer one triangulation way over the other.
Which can be necssary on some occasions.I'll show an example for that later
when posting the non planar stuff.Hopefully by tomorrow.
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 28, 2015, 01:45:45 pm
Quote from: j meyer on July 28, 2015, 01:06:52 pm

Modeling in quads is the way to go,although an occasional triangle won't hurt.
Ngons are to avoid.



Again, it depends of the context. There is no need to model only with quad just for the sake of it.

'Only quad' is needed for a 'subdivision modeling workflow', where the mesh will be deformed in animation (skinning, morph etc).
Actually quad is not the only thing you have to deal with, you also have to care about vertex valence, but that's an other story.

If the model will not be deformed (often called hard surface modeling), then you can use n-gons too. As long as it's looks fine in the viewport, who cares.
In the past some software didn't accept to subdivide ngons topology, but it's not the case anymore.

If you are not using subdivision surface on the top of you model, then there is no rules. Of course n-gons should only be
used for flat surface , and maybe you need to add some edges here and there to help the internal triangulation to resolve
concave geometry, but that's all.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 28, 2015, 01:55:38 pm

It depends like Paq said where the ngons are used.
On a flat surface they get triangled without problem mostly.
Terragen triangled the obj itself here for example without problem.
But with displacements and normals etc. used in Terragen it can get ugly.
So in Terragen with displacement i would avoid them all the time.

Here is the file itself with the object.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 28, 2015, 04:16:43 pm
paq - This is about modeling/models and Terragen!
        I at least try to keep my info related to that.
        Thanks.

Kadri - The last time I tried that was with that moviemodels train wagon,if you remember
          and that did not render the large flat surfaces.
          There might be exceptions or Matt has changed something in the meantime,don' know.
          Will try your file and tell here.
       
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 28, 2015, 04:26:15 pm
Works on my end too.Strange. 
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 28, 2015, 04:30:17 pm

I would like to see the old model you mentioned. Curious too.
Probably the vertices weren't at the same axis-surface or displacement was used if it doesn't worked then.
But maybe Matt might have made changes too of course.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 28, 2015, 04:32:06 pm

Or it was a normal problem?
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 28, 2015, 04:45:34 pm
Now for the shader stuff.

This time it's about how to prepare your model inside your modeling application
in a way that TG creates all the Part nodes and their corresponding Shader nodes
you want your model to have.

It may be of help to know that the file format we are using (.obj) just saves the coordinates
of the vertices (points) of a model and - if -the vertex normals.And some other stuff that can
vary from app to app.No info as for separate geometry parts.That's done via materials.
The material/shading information is saved within the accompanying .mtl file.(put the mtl file
in another folder and load the obj without it and you'll see the difference.No greyPart node,
just the red Parts shader node.The model renders pure black unless you connect some Default or other shader to it.)
There are lots of parameters that won't be exported from your modeling app or imported by
your target app.A few are,but most of them not.
That goes for TG and other rendering software.

So I found it a good habit to make the final shader tuning in TG instead of trying to do as much
as possible beforehand,but that's just me.


A little visual aid as to what is what:

[attachimg=1]

The demo model is composed of 6 separate parts of geometry and has one shader/material
assigned.It's the material that's on every model by default.Here it's named default,too.
In your app it may be named differently.

[attachimg=2]

When exported like that your model will have one grey Part node and it's corresponding
Default shader.
The nodes inside the Parts shader node:

[attachimg=3]

Renders like this in TG

[attachimg=4]

So,what to do?
Back in your modeling app you select one of your model's parts and assign a new material/
shader to it.Name that material/shader properly.Avoid spaces,use underscores or hyphens.
For example: starting with the cube,assign a new material to it and name it cube.
You don't have to do anything else to this material now.Most of the settings won't export
anyway.
Do that for the other parts as well.
In the example I gave every material it's own color,but that's just for demo purposes,easier
to see what has been done.
You'll also notice that I've 'grouped' the spheres to show what's possible generally.
Now our model has still 6 parts,but this time three materials/shaders.

[attachimg=5]

The nodes

[attachimg=6]

Rendered

[attachimg=7]

That's better,we can have a different shading on the different elements now.
But it's still not enough! More shaders,gimme more shaders...aahrff.


to be continued in the next post.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 28, 2015, 04:51:12 pm
Back to the modeling app again.
There is something else we can do.We can assign a material to groups of polys,too.
It doesn't have to be separate geometry necessarily.
Like this for instance:

[attachimg=1]

The nodes

[attachimg=2]

And rendered

[attachimg=3]

Pretty easy.

The above tries to illustrate the general principle.
And the principle goes for both non UV-mapped models -like in the example - or models
that are UV-mapped.And of course combinations.

Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 28, 2015, 05:07:51 pm
Kadri - It was the free model from that guy who made a special sale some time ago.
          The alleged movie quality models.You posted in that community thread,too.
          Think I've got it on a stick still.
          Opened that in TG,full of missing geometry,opened it in wings same result.
          PoseRay triangulated it on loading and after that the geometry was ok.
          I've had that over the years many times especially with Lightwave models.
          There is a DS9 runabout out there that I remember for that very reason.
          No displacement involved as far as I recall.
          And no it was definitely not what you call a normal problem.
          Missing geometry means you see big holes in your model.
          Will try it again and post an example.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 28, 2015, 05:10:44 pm

I see. If i find time (before you) i will have a look too :)
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 28, 2015, 05:36:21 pm
Here you go.
In Wings3D

[attach=1]

In TG

[attach=2]
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 28, 2015, 05:43:10 pm

Without using Poseray it looks problematic yes.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 28, 2015, 05:53:00 pm

I looked at one problematic part.


[attachimg=1]



It is flat but it does have a hole in it.
Not sure if the others are all the same but Terragen can't triangle these kind of surfaces as it should maybe?
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 28, 2015, 06:10:42 pm

I looked  a little closer.
It gets a little more confusing for others maybe.

Not sure in what way you used the term ngon above Jochen but i mean both of them (planar-flat and non planar-flat).
In this example they are ngons but they look planar mostly

My own basic example does have a ngon surface but it is planar and doesn't have a hole in it.

The train parts that don't show up in your example are ngons but they have mostly holes in it.
Haven't looked at the others.
Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 28, 2015, 06:13:45 pm
Hi Kadri,

Yes from my test Terragen 'simply' delete or discard any n-gons.
So just select all n-gons in LW (I think there is a statistic panel in lw too right ? where you can select every poly with more than 4 vertex), and triple them.

@ j meyer,

What I was trying to explain, it's not because Terragen doesn't support n-gons that you have to avoid them during modeling task in you DCC.
The little train was a perfect example, sure you have to triple ngons, but only when you export your model for Terragen.

I just wan't to avoid people wasting modeling effort creating full quad topology when it's actually not needed, excpet like Kadri said, if you want to prepare the model for texture displacement.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 28, 2015, 06:24:55 pm
Quote from: paq on July 28, 2015, 06:13:45 pm
...
I just wan't to avoid people wasting modeling effort creating full quad topology when it's actually not needed, excpet like Kadri said, if you want to prepare the model for texture displacement.


I actually don't care for quads or triangles until i stumble in a problem.
I do mostly only hard modeling. Not that i am a good modeler anyway  :P
But except the shadow problem in Terragen i mostly don't have those kind of problems.
After a while you model in the way you should without much effort probably out of habit.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 29, 2015, 01:02:29 pm
paq -
Quote....The little train was a perfect example, sure you have to triple ngons, but only when you export your model for Terragen....

That's what this thread is about:modeling for use in Terragen,modeling to export your model
to Terragen.
And,please,triple means multiply by 3,triangulate is the word.
Just trying to avoid more confusion as we already have here.


Kadri - the term ngon in regard to modeling means any face with more then 4 edges.
and that's how I use it.Has nothing to do with non planar or planar.
Holes may make it worse,but I had these problems without holes also.

Title: Re: 3D Models and Terragen - Basics
Post by: paq on July 29, 2015, 02:18:07 pm
Quote from: j meyer on July 29, 2015, 01:02:29 pm

That's what this thread is about:modeling for use in Terragen,modeling to export your model
to Terragen.
And,please,triple means multiply by 3,triangulate is the word.
Just trying to avoid more confusion as we already have here.


Thanks for the grammar lesson, but 'triple' is the command name to triangulate a mesh in Lw and Modo.
I have the feeling you are making the whole 'modeling for Terragen' idea over complicated, establishing modeling
rules when actually it's just a matter of export options.

As my limited english seems to add an other layer of confusion, I'll just stop posting  (but keep reading  ;))
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 29, 2015, 02:38:59 pm
I don't see a reason for you to stop posting.
English is not my first language,too.We shouldn't press this issue too much,really,
at the end we are all using bad english even that native speakers. ;)

Didn't know about that LW command and I bet some others did not know also.
But still,if some call it triangulate here and others triple none of the guys reading
this will be able to follow without problems.
We should all use the same terms here that's all I'm asking for.
Your knowledge is still appreciated.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 29, 2015, 05:08:39 pm
Quote from: j meyer on July 29, 2015, 01:02:29 pm
...
the term ngon in regard to modeling means any face with more then 4 edges.
and that's how I use it.Has nothing to do with non planar or planar.
...


Yes but non planar ones makes them more problematic.
That is what i tried to say for my test file with the ngon surface.

I will have a look later with some other object.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 29, 2015, 05:31:22 pm
Curious to see what you'll find Kadri. :)



We were talking about non planar faces lately.Actually we are still on it.
What is a non planar face,you might ask.
A non planar face is a four or more sided face with one or more vertices not on the same
plane as the others.
Errh...What? ???
Take a triangle polygon.It has three vertices (points) connected by three straight edges.
It's flat or level.If you now take one vertex and move it up you still have a flat polygon.
No matter which vertex or how high above the other two it will always be a flat face.
Stretched maybe,but flat.
Now take a four sided polygon,a quad.That has four vertices connected by four straight edges.
Let's assume it is flat at this moment.Take a vertex and move it up as before and you don't have a flat surface anymore.It's a non planar face now.
You will see why that can be problematic further down below.

The first example deals with just slightly non planar faces on the side of a cube.
The image should illustrate what has been done to the cube.

[attachimg=1]

Now three images of the cube rendered in TG each with a different lighting angle.
Left them a bit bigger so you can see better.
[attach=2]

[attach=3]

[attach=4]

Depending on the light angle it can be problematic even with such a small amount of
'non planar-ness'.

But it can be much worse than this.
The second example will show.


to be continued in the next post
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 29, 2015, 05:37:51 pm
This second example will show one aspect of the non planar faces a bit more clearly,hopefully.

[attachimg=1]

As you can see the faces are somewhat more non planar than in the first example.
Things like that can show up on curved surfaces for instance.
And here we also see why it can be crucial sometimes to choose the triangulation variant rather than leaving it up to TG to triangulate it.
As mentioned before,usually it's not necessary to have your model triangulated,but in cases like this it's definitely better to triangulate at least some faces yourself.

The 2 variants of triangulating.

[attachimg=2]


I show these before the TG-rendered results so that you get an idea of what's happening when
importing and rendering the untriangulated model (like shown in image #1 of this post).

TG-rendered

[attachimg=3]

You see it can actually change your geometry in a way that's not desired most likely.



Think I should mention that none of my statements on modeling in this thread (or elsewhere)
is meant to be obligative or canonical.
These are rather guidelines than rules.Based on my personal experience and observations.
I don't claim them to be complete or free of mistakes.
Use at your own risk.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 29, 2015, 06:12:10 pm
Kadri - Forgot to have a look at your model yesterday.Too much other stuff in my little
          brain.Just now I thought of it again and after having a look the solution is more than
          simple.The model that's in the Project assets folder has no ngon.The shape has more
          than four corners,but it's already triangulated and thus no ngon anymore.
          And that's the reason why it renders flawless.
          Seems we had a litlle misunderstanding.Hope it's clearer now.
          Sorry for the delay.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 29, 2015, 07:18:04 pm

Good examples Jochen.


Quote from: j meyer on July 29, 2015, 06:12:10 pm
Kadri - Forgot to have a look at your model yesterday.Too much other stuff in my little
          brain.Just now I thought of it again and after having a look the solution is more than
          simple.The model that's in the Project assets folder has no ngon.The shape has more
          than four corners,but it's already triangulated and thus no ngon anymore.
          And that's the reason why it renders flawless.
          Seems we had a litlle misunderstanding.Hope it's clearer now.
          Sorry for the delay.


Yes i was trying to say there that Terragen trianglated that surface without problem.

And this example is kinda the same actually. I think the problem you had even with planar ngons is similar to this.
In your train example this did not show up.But after Poseray i had no problem with it.

I exported this glass part from the same train object that doesn't show up in your image.

First i exported it as it is directly from Lightwave.
I could not see it in Terragen so much i tried. The node was there but it was like a ghost :)


[attachimg=1]




Then i tripled it in Lightwave and exported it ones more directly as an OBJ file.
This time it did show up in Terragen


[attachimg=2]


It looks like Terragen can't do the triangulating as it should on some surfaces.
How or why it happens Matt knows better.

By the way my 3D work and thoughts are always work in progress ;)
Paq or any other ones don't shy away. It is Jochen's thread but i am sure he thinks the same way (as he already said).

So yeah it looks like converting is one of the important problems especially with ngons probably.
Title: Re: 3D Models and Terragen - Basics
Post by: Matt on July 29, 2015, 07:38:08 pm
Terragen's OBJ Reader will triangulate quads, but faces with 5 or more edges are not supported; it simply ignores them.

Matt
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 29, 2015, 07:44:53 pm

Wow...Very fast response, thanks Matt.
As always while you are here another question,any changes planed for this behavior Matt? :)
Title: Re: 3D Models and Terragen - Basics
Post by: Matt on July 29, 2015, 07:46:38 pm
We don't have any plans to change this yet.

Matt
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 29, 2015, 07:48:54 pm

Thanks Matt.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 30, 2015, 02:08:19 am
My experience in LW is that tripling/triangulating automatically doesn't always choose the most logical connections for the new edges. So I do the most important ones by hand. I don't know what Poseray does in that respect.
Also, and this may be a strange habit of mine, I don't like the messy triangles when tripling a more complicated ngon. So for house walls with windows, I usually cut the whole walls up in enough squares, then manipulate the window planes to their locations and move them inward by hitting 'b'. Instead of cutting a hole into a plane from another layer with a cube or other shape, that is.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 30, 2015, 02:29:52 am

It looks messy but not sure how to make it look better automatically without doing it manually as you do Ulco.

If the surfaces do look good without a problem i don't care. But i know some care much more and not only you Ulco :)

Was curious and exported the original from Poseray too.
This is how the Poseray exported OBJ looked in Lightwave Ulco.


[attachimg=1]
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 30, 2015, 02:36:46 am
Interesting Kadri. It's quite different. And I know, my 'behavior' is probably a bit too preoccupied with clarity. By the way, I wonder why the normals of the new planes/triangles are not centered, but sometimes on the edge. I guess that also makes a difference in how angles are calculated for smoothing.
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 30, 2015, 02:52:23 am
Quote from: Dune on July 30, 2015, 02:36:46 am
... By the way, I wonder why the normals of the new planes/triangles are not centered, but sometimes on the edge. I guess that also makes a difference in how angles are calculated for smoothing.


Ahh that is a thing that i wanted to know too since years and always forget to search about :)
Have to look for that. Maybe others already know it here?
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 30, 2015, 06:00:16 am

Ulco i asked in the Lightwave forum. Can't say anything about it but the answer is this:

"Normal that is displayed in viewport wireframe is just hint. Visualization.
Real normal vector, such as during rendering, if mesh is smooth is constantly varying.
It's interpolated across entire polygon.

Wireframe drawn normal dashed line is in center of polygon, that's it: sum all vertex positions and divide by quantity.
If you have two or more points not merged, not welded, displayed normal vector will be probably moved to direction of these not merged points.
f.e. take pen tool and make quad, drag one point with snapping enabled to one of remaining three.
It's quad poly, but looks like triangle. Where is center of displayed normal?
"

It is Sensei's answer. He is a plugin maker for Lightwave that knows what he does.You might know him.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on July 30, 2015, 08:24:22 am
Thanks, Kadri. I think I remember his name form the plugins indeed. Interesting. Learned something again. Nothing to worry about then  ;D
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 30, 2015, 08:33:52 am
Quote from: Dune on July 30, 2015, 08:24:22 am
... Nothing to worry about then  ;D


Yeah that was what i understood too :D
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 30, 2015, 02:09:17 pm
First of all: Thank you Matt!  ;D
I for one hope that behaviour (TG ignoring ngons) won't change.

Ulco - To me it seems like a good habit. :)

Kadri - I was refering to your obj file opened in Wings3D.Which I totally forgot
          to do the day before when I just rendered in TG.
          Hope Matt's post cleared that up in the meantime.


As far as I have observed PoseRay's auto triangulation isn't better.If you need things
to be in a certain way you are always better off doing it 'manually'.
As always,from my point of view and judging by my experiences,of course.

         
         
Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 30, 2015, 08:17:58 pm
Quote from: j meyer on July 30, 2015, 02:09:17 pm
...
I for one hope that behaviour (TG ignoring ngons) won't change.
...



Every software i know can use them in this or that way why shouldn't Terragen?



Quote from: j meyer on July 30, 2015, 02:09:17 pm
...
As far as I have observed PoseRay's auto triangulation isn't better.If you need things
to be in a certain way you are always better off doing it 'manually'.
As always,from my point of view and judging by my experiences,of course.



Not that i think different, but if you use the flat surface as a flat surface (my above first response is related to this too) other then esthetics there is no difference.
If you want to displace that flat surface,then yeah it isn't a flat surface anymore and you have to model accordingly of course.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on July 31, 2015, 12:37:39 pm
QuoteEvery software i know can use them in this or that way why shouldn't Terragen?

There are programs that can't.And as things are you have to model differently for almost
every purpose.That's cumbersome enough.If that's changing every once in a while it would
not make things easier.


My quoted PoseRay remark (from the post above) is refering to:
QuoteMy experience in LW is that tripling/triangulating automatically doesn't always choose the most logical connections for the new edges. So I do the most important ones by hand. I don't know what Poseray does in that respect....



Title: Re: 3D Models and Terragen - Basics
Post by: Kadri on July 31, 2015, 07:13:21 pm

Ignoring ngons fully looks one step worse to me then trying to triangulate them (even if a little problematic).
That train object could be imported without a problem with basic triangulating even with all the ngons for example.
Anyway it is up to Matt and dealing with this kind of converting issues isn't any news so i don't care so much.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on February 18, 2017, 11:46:55 am
And now for something else.

Some days ago Ulco wrote:
QuoteIt's too bad you can't have 2 UV-maps on an object. I often use a tiled texture for parts, hardly ever one total UVmap. In the latter case you can paint dirt in crevices over the texture as a separate map, have it stream along sides with wind, etc.


There is a solution to achieve that effect. It is not two UV maps, still one, but used in two ways.

[attachimg=1]

In the above example image you can see that the tiling can be changed independently, so that the
other texture is not affected.
How? See next post.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on February 18, 2017, 12:00:06 pm
I think I know how you do that; by changing the size of a UV (repeated) image map to say 0.1 instead of 1, and adding it to the 'normal' UVmap. But for dirt in crevices you's really need one map of the whole object so you can paint in the dirt in crevices. That's still hard I think. If you have a solution for that, I would be thrilled.
For stone walls I often use a repeated default texture; the UV map well exceeding the space available (for 1 tile).
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on February 18, 2017, 12:27:57 pm
Nope, not like that. It has a map for the whole thing, except the top part.
Did it that way, because your tree objects always have these caps and
I didn't know for what kind of model you'd like to have it.
My next post will explain.
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on February 18, 2017, 12:32:53 pm
I can't wait! Sounds cool.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on February 18, 2017, 12:57:20 pm
Ok, here it comes.
For the example I used a square based pillar/beam to show the principle on something
easy. So this pillar is 4 squares high and since it has 4 sides it is 4squares wide, too.
Deleted the bottom and separated the top square to be an object of it's own.
Then I took the pillar into UV-mode and cut it on one edge and unwrapped it.
That resulted in a square that fills the whole UV space ( 0-1 ).
The top, although not relevant for this example, got unwrapped, too.
Set up like that the pillar was exported to .obj format.
Opened the model in TG and started to load the images and assign them.
These are the images in use.
[attachimg=1]
The node setup
[attachimg=2]
The alpha mask is used to cut out the white from the dirt layer image, which btw
is representative for a handpainted dirt layer.
The tiling texture is applied via an image map shader to make use of the repeat x
and y features. And that is the crux in conjunction with scale.
Just divide the size of 1 by the amount of the desired tiling. Like 0.5 for 2 tiles,
0.25 for 4 and so on. See pictures, please.
[attachimg=3]
[attachimg=4]
[attachimg=5]
Pretty easy and straightforward.
Of course you can connect the nodes in different ways, the above is just one example.
It's for the principle.

Hope it'll give you some idea(s).
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on February 18, 2017, 11:24:52 pm
Brilliant, is there anyway this could be added to the WIKI under textures...?
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on February 19, 2017, 01:47:31 am
This is what I meant in reply 109, but I'm afraid it wouldn't work for a building where one part (say all walls) exceeds the UV area. That whole section would have to be within the UV space, or you get tiling of the dirt painted in that UV space as well. Dirt won't be on the right spot, except maybe in the UV area.
I also think that if you have 'gradual' dirt, you need a glass shader or a gradual opacity, which is not the case atm.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on February 19, 2017, 10:32:39 am
Sorry Ulco, I misunderstood reply 109 obviously.

QuoteI'm afraid it wouldn't work for a building where one part (say all walls) exceeds the UV area. That whole section would have to be within the UV space, or you get tiling of the dirt painted in that UV space as well. Dirt won't be on the right spot, except maybe in the UV area.


That's actually the point of this method. Having unwrapped parts exceeding the 0-1 space is what is
causing the tiling, as we know. So this method takes care of the tiling in TG exclusively while the
unwrapped map does not exceed the 0-1 space and is, thus, paintable.
Gradual dirt might be a problem, haven't tried all options. Although masking the surface layer -
what I did here - works with grey values iirc, doesn't it?. (my map here hasn't any, just b/w)
The only other way I know of is doing it in ZB - applying a tiling tex, converting to polypainting,
re-mapping and then drawing your dirt map - as mentioned elsewhere before.

Bobby - feel free to do so.
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on February 19, 2017, 11:27:40 am
Quote from: j meyer on February 19, 2017, 10:32:39 am

Bobby - feel free to do so.


Hmmm, it requires converting to an html page and I have no skills there...was hoping Oshyan or someone could do it...
Title: Re: 3D Models and Terragen - Basics
Post by: Dune on February 20, 2017, 02:36:27 am
QuoteSo this method takes care of the tiling in TG exclusively while the unwrapped map does not exceed the 0-1 space

I thought about after shutting down yesterday and came to the same conclusion, that would be the way indeed; do it the other way round. The only 'difficulty' being the exact ratio of tiling in TG, that would need some figuring out. Clever way. Must try it some day. Thanks Jochen.
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on February 20, 2017, 12:18:10 pm
 :)
Title: Re: 3D Models and Terragen - Basics
Post by: archonforest on March 21, 2017, 02:16:57 pm
Hi Jochen :D

So I want to dirt up a bit my train and the train cars. Just a bit. Right now I am using that technique that you showed in this thread earlier with the heli. It works but it does not looks real or something. Perhaps my set up is wrong? Will post a picture in a sec...


The left uses a PF into the color. The right one uses the technique you showed earlier...
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on March 21, 2017, 03:02:29 pm
At first glance it looks like you might need to pipe your power fractal through a
transform shader set to use world space.
But I'm going to download the train car model and have a look.
Title: Re: 3D Models and Terragen - Basics
Post by: archonforest on March 21, 2017, 03:09:12 pm
Quote from: j meyer on March 21, 2017, 03:02:29 pm
At first glance it looks like you might need to pipe your power fractal through a
transform shader set to use world space.
But I'm going to download the train car model and have a look.


Got it. Will try it also. When u say transform shader you mean transform input shader right?
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on March 21, 2017, 03:19:21 pm
Quote from: archonforest on March 21, 2017, 03:09:12 pm
Quote from: j meyer on March 21, 2017, 03:02:29 pm
At first glance it looks like you might need to pipe your power fractal through a
transform shader set to use world space.
But I'm going to download the train car model and have a look.





Got it. Will try it also. When u say transform shader you mean transform input shader right?



That's the one Atilla
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on March 21, 2017, 03:21:25 pm
Yes,thanks Bobby, a transform input shader. The transform merge also works, but the connections
are slightly different.
Had a quick look at the model and a transform shader set to world space is definitely
required to get the PF working correctly.
Title: Re: 3D Models and Terragen - Basics
Post by: bobbystahr on March 21, 2017, 03:25:59 pm
Quote from: j meyer on March 21, 2017, 03:21:25 pm
Yes,thanks Bobby,




Just back from getting my income taxes done for free and I'm getting a new cpu from them I think....I have a RAM cashstash so with any luck in 6 weeks I'll actually have the computer I wanted with the new AMD Ryzen7 and 32 G RAM.
Title: Re: 3D Models and Terragen - Basics
Post by: archonforest on March 21, 2017, 03:38:29 pm
Quote from: j meyer on March 21, 2017, 03:21:25 pm
Yes,thanks Bobby, a transform input shader. The transform merge also works, but the connections
are slightly different.
Had a quick look at the model and a transform shader set to world space is definitely
required to get the PF working correctly.


Wow what a differennt! Tku Jochen. It works well. Now I just need to tweak it. One more question Jochen. Can u explain with some words what is happening wit the PF? If its too complicated then do not do it. I just like to understand how things works so I can think with it.  :D
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on March 21, 2017, 04:10:34 pm
If you try to put a Power Fractal on a UV mapped surface only a very small,limited area
of the PF is applied to model - or a part of it - and depending of the shapes and count
of polygons it will get stretched or pinched.
World space makes TG 'see' the model's surface as a whole independent of the models
UV mapping. Try to imagine the Power Fractal's pattern as a huge sponge or so filling
the whole virtual space TG provides. With world space enabled the model stands within
this sponge and the PF pattern is applied to the model's surface accordingly.
Easy example: Let's say your model is a solid cube. Then a cube shape is cut out of that
aforementioned sponge, thus leaving a cube shaped hole in the sponge. If you now imagine
yourself standing in that hole  the pattern you would see on the walls and the ceiling and
bottom is what gets applied to the models surface.

Hard to explain somehow.
Title: Re: 3D Models and Terragen - Basics
Post by: archonforest on March 21, 2017, 04:21:06 pm
Quote from: j meyer on March 21, 2017, 04:10:34 pm
If you try to put a Power Fractal on a UV mapped surface only a very small,limited area
of the PF is applied to model - or a part of it - and depending of the shapes and count
of polygons it will get stretched or pinched.
World space makes TG 'see' the model's surface as a whole independent of the models
UV mapping. Try to imagine the Power Fractal's pattern as a huge sponge or so filling
the whole virtual space TG provides. With world space enabled the model stands within
this sponge and the PF pattern is applied to the model's surface accordingly.
Easy example: Let's say your model is a solid cube. Then a cube shape is cut out of that
aforementioned sponge, thus leaving a cube shaped hole in the sponge. If you now imagine
yourself standing in that hole  the pattern you would see on the walls and the ceiling and
bottom is what gets applied to the models surface.

Hard to explain somehow.


TKU! Great info. You should write a book man! I would buy it even for 100 bucks!
Title: Re: 3D Models and Terragen - Basics
Post by: j meyer on March 22, 2017, 02:39:51 pm
 :) You're welcome.
And remember when the next question pops up. ;)