Hi all

Just started using Modo (really like it so far).

Am wondering what the best format to export from MoI into Modo is?

Also, any other Modo tricks in relation to using MoI?

(or heck, just any Modo tricks in general lol)

-EDIT-

For example, I just imported a .lwo file, with some flat surfaces from moi, and half of them were back to front (backfacing).

Also which formats best support MoI's "styles"?

Hi NightCabbage,

1) .lwo is the best format for modo, using ngones, and you can turn 'weld vertices along edges' on.
2) Styles are converted into surfaces names
3) Don't forget to give some objects name in Moi, every geometry with the same name = 1 object (layer) in modo.

About the normal orientation, you can try to only use solids, so MoI will align normals 'correclty'. For open surface, you have 50% to have inverted normals. A double sided surface will be assigned into modo anyway.

You can try to reflip normals by hand in modo (select a poly -> flip), but expect if it was fixed, (havn't test it in the new service pack), the vertex normal will be wrong.

Thanks PaQ!

Hmmmm, no matter what I do, (when importing an lwo file) whenever I assign a material to one item/object with a style - each other item/object with that style gets the same material.

Even when I select the item in modo, by itself, and then hit 'M' to assign a new material - all that does it replace the current material for every item with that style (from moi).

For example, if I export a model from moi containing many objects, how can I assign different materials to them in modo?

-EDIT-

Oh, it's because of the shader tree, right?

I really need to learn how to use that properly - it's going to take some getting used to...

I'm not used to one material having an effect on more things than I've assigned it (if you let it flal through to other items I think).

Hi NightCabbage,

Yes, you probably have to learn a bit Modo shading system as you question looks more modo related.
Maybe an quick view on luxology.tv could help to give you a good start

http://www.luxology.com/tv/training/view.aspx?id=280

Also have a look to the Related Videos in the bottom of this page :

Shader Tree Essentials Intro
Poly Masks
Item Masks

...


btw dont hesistate to create an account on the luxology forum, people are (often) really nice, and
you will have fast replies to your problems.

Paq, wasnt there some thing with having to export each object individually? because they get grouped in modo and will only take 1 material? i could be wrong, as I only played with modo for a few weeks and that was a few months ago.

Look at this Tut: http://tapetube.com/2009/10/importing-iges-into-modo-moi-3d
There is everything explained even in the comments, that MoI exports a vertex-map that could mess things up.
Even like the users in the comments I would def agree that there has to be something for switching on/off the export of this vertex-map in the export dialog which really makes no sense in modo and could disturb newbies, as there is a toggle function for smoothing in Modo by default.

Hi Nick,

> Paq, wasnt there some thing with having to export
> each object individually? because they get grouped
> in modo and will only take 1 material?

There shouldn't be any need to export each object as separate files or anything like that.

Objects in Modo aren't restricted to only have 1 material for the whole object, you should be able to assign separate materials to different faces within the same mesh object.

Also you can control how things are grouped into mesh objects in Modo by assigning names to the objects in MoI.

If you assign the same name to 2 objects, and you also have "Combined same name objects" turned on under Options > Import/Export, then those objects will get grouped together as one mesh item in the LWO file.

- Michael

Hi Anton,

> Even like the users in the comments I would def agree that
> there has to be something for switching on/off the export of
> this vertex-map in the export dialog which really makes no
> sense in modo and could disturb newbies, as there is a toggle
> function for smoothing in Modo by default.

But that's definitely not true that the vertex map "makes no sense" in Modo - it's actually very important to get the vertex map to come through into Modo in order to get the best quality shading.

If you don't get the vertex map through, then instead Modo will create vertex normals for smoothing by just averaging the normals of surrounding poly faces. This tends to create shading glitches. The vertex normals that MoI writes out on the other hand come from the original NURBS surface, so using those for shading helps to keep the shading look exactly the same as the original NURBS object.

There are still some bugs in Modo in vertex normal handling when editing geometry though, which hopefully they will fix at some point. Some operations such as flipping should also flip the vertex normals but currently do not, and some other kinds of operations that alter the mesh's shape should actually delete the vertex normal map (since the vertex normals are only meant to go with one particular mesh shape) but they don't.

But for doing a regular rendering, you usually will want to have the vertex normals come through, it's the way that you get the best quality shading and have the object look the same as the original NURBS object.

- Michael

LWO imports fine. The vertex normals come in properly as well. If there is a vertex normal map, Modo, correctly, ignores the material's smoothing options, so I don't understand the previous comment. You don't have to worry about smoothing. Scaling is spot on as well.

MoI Style = Named Material poly group in Modo. Don't worry too much about object names. They will be given a separate mesh item in modo but will all be grouped under a group with the name of the imported lwo file.

You can change the materials in Modo to anything you want as long as you keep the Name. Because Modo allows Nesting, you could have a style in Moi called RED, for example. On import to Modo, a Polygon Tag called RED is created with a material in it. You can then nest below Red any material you like, say Black Plastic, as long as it is a child of RED. Pull all these materials corresponding to MoIs styles out of the group with the name of the mesh, then delete the group. I have attached a screen shot of how the shader tree should look (this is from my Canon A1 model that I put in the gallery yesterday).

The big, big, advantage of Modo's shader tree approach is when you want to change your model in MOI and re-import to Modo. Just save out the new MoI mesh as an Lwo file (overwrite the old one is easiest). Open your old file in Modo. In the ITEM tab, delete the ITEM group containing your old mesh. Import your new LWO mesh. This will create the item group again. Switch to the SHADER tab. All the materials you set up previously are still there. There will be a new group with the name of the mesh. just delete it and all your materials are reapplied to the new mesh automatically. If you created any new styles in Moi after the first import, pull them out of the group before you delete it (if you look at the materials in the group before you delete it, all the ones you already have will have (2) at the end of the name. Any that don't are new.)

It sound complicated but it isn't. 3 clicks to update. 1) Delete old item group 2) import new mesh 2) delete imported material group. That's it.

C4D on the other hand is much more complicated as the materials are attached to each mesh item so when you reimport you have a lot of work to sort out which material is which.

Copying a UV map when you re-import in Modo can be done but it is a bit advanced and not intuitive. Stick to non-UV mapping if you can as these are carried from one mesh to another with the material unlike UV maps which are mesh specific.

>> If you assign the same name to 2 objects, and you also have "Combined same name objects" turned on
>> under Options > Import/Export, then those objects will get grouped together as one mesh item in the LWO >> file.

What the deuce!? I never saw that option before. D'oh!

Hi NightCabbage, just some more details on this part:

> For example, I just imported a .lwo file, with some flat surfaces
> from moi, and half of them were back to front (backfacing).

By flat surfaces you mean some planes that are non-solid open surfaces?

Those will not necessarily have any one fixed orientation for their normals - it will depend on things like whether you drew some of their construction curves clockwise or counter-clockwise or things like that.

Unlike a solid, an open surface all by itself just does not have any automatic "correct" orientation to it.

Here's an example - say you draw a vertical plane like this:




If it just stays as an independent isolated surface like that, there isn't any way for MoI to know whether it is supposed to be the front part of an object like this:



or whether it is supposed to be the back part of an object like this:




This is not unique to MoI or even NURBS surfaces - if you build objects in a poly modeler one individual polygon at a time you will run into the same thing.


But in MoI if you join all the individual surfaces that touch each other like that into a completely closed solid, then there is a well defined inside and outside to an object like that and all the surface normals will automatically get oriented towards the outside of the solid object.


If you are not making a full solid, then you can either flip the output in your polygon modeling program, or you can also set up a keyboard shortcut with the Flip command in MoI which you can run on an open surface object in MoI to flip which side is considered to be the positive surface normal side.


In the future I want to add a kind of "direction showing mode" that would show the negative surface side of the object in MoI in red so that you could more easily see which side was which. Right now there isn't anything for that, mostly because there isn't really anything in MoI itself that is particularly sensitive to that.


- Michael

Lots to read :)
And lots of helpful information for a newbie like myself! Thanks guys!

PaQ - thanks for that Lux TV video, it was good. I'll try to hunt some more down.

So am I correct in saying this:

A material can be applied to an object in two ways...

a) an item mask - for any item to have that material
b) poly tags - for any polygons to have that material

Hmm, could someone tell me what the difference is between these two trees:


(a poorly done photoshop of Steve's example tree :)

I'm wondering what the extra nodes in the tree are for? Do they do anything, or are they just like folders that hold things (and thus there's no point in having a folder in a folder)?



So it sounds like I should use MoI's Styles to define each of the end model's material groups in modo?


(Michael)
> In the future I want to add a kind of "direction showing mode" that would show the negative surface side
> of the object in MoI in red so that you could more easily see which side was which. Right now there isn't
> anything for that, mostly because there isn't really anything in MoI itself that is particularly sensitive to that.

Ah that sounds perfect :)

Also, does the MoI option for LWO files "scale output units to meters" literally convert each 1 unit of MoI to a meter in Modo?
(what's the best way to deal with smaller units?)





> What the deuce!? I never saw that option before. D'oh!

Lucky it's enabled by default then :D

Hi NightCabbage,

> So it sounds like I should use MoI's Styles to define each
> of the end model's material groups in modo?

Yup, that's one of the main purposes for MoI's Styles mechanism - to give you a way to set up material assignments for exporting to LWO and OBJ formats.


> Also, does the MoI option for LWO files "scale output units to meters"
> literally convert each 1 unit of MoI to a meter in Modo?
> (what's the best way to deal with smaller units?)

LWO files don't have any way to mark what units the file are in, and the way that Modo works it assumes that the units of the LWO file are in meters.

So for example if you create a line that has length = 5 cm in MoI and save it to LWO, Modo will actually interpret that value of 5 as being 5 meters.

But if you enable that option, then MoI will scale what it writes into the LWO file to convert it to meters, so for example if you have 5 cm in MoI with that option enabled it will scale all coordinates by 0.01 to convert from cm into meters, resulting in the value of 0.05 being written to the file. Then when Modo reads it, it will see the value as 0.05 meters which will be the same size as your original 5 cm in MoI.


Modo is not the only program that works with LWO files though, and other programs may not have the same "assume the LWO file is in meters" behavior to it, that's why that's an option to do the scaling.

- Michael

>>A material can be applied to an object in two ways...

a) an item mask - for any item to have that material
b) poly tags - for any polygons to have that material

Hmm, could someone tell me what the difference is between these two trees:


(a poorly done photoshop of Steve's example tree :)

I'm wondering what the extra nodes in the tree are for? Do they do anything, or are they just like folders that hold things (and thus there's no point in having a folder in a folder)?
>>>

If you look at the properties of a shader group in Modo, there are various ways to control what it does. These groups are essentially masks, and Modo applies the materials starting at the bottom of the tree and working upwards. Things higher in the tree override lower items universally unless they are restricted in some way by a mask. The mask can be by Item or by a Polygon Selection. In my example the Chromium Plate Cast is a group that has no restriction (the polygon tag field is set to "All"). It is a convenient way to group a preset. The whole preset can be swapped by deleting the group and adding a new preset. However, it is the child of the Matr: chrome group. This restricts itself and any of it's children to the polygon selection "chrome" (MoIs style applied to objects and faces). A slightly more complex but very useful attribute is the "Apply to Sub Group" option, which then takes the masking from the child groups. This allows you to set one material as the first child of the group and have it apply to all masks that are also children of the group but not to anything else.


Modo's shader tree is quite different to other 3D apps (it is much more like Photoshop layers)and requires a bit of study to fully understand it. One thing that helps enormously in debugging the shader tree is the Render Preview Window. If you right click the preview window, the pixel under the mouse is evaluated and a pop-up shows the items in the shader tree that have contributed to that pixel. You can then click on an item in that list and be taken straight to that item in the shader tree. I have attached a screen shot of the effect of right clicking the preview window.

There are some good tutorials on Luxology's web site. In the on line help for Modo there are a number of videos that explain the shader tree and masks in depth.

Hey Michael!
Just wanted to tell this issue with the vertex map. And since I'm new to Modo and just testing MoI this was an issue I couldn't solve for a day and was really happy to have found the comments and this tutorial I've mentioned.
So my intention was to export some l beveled objects (lots of facets) to further render in Modo and so I didn't know what was going on at this time.

My suggestion would be to implement a checkbox for switching on and of this v-map-export even to clear things up.

Vertex Maps are exported from MoI and imported by Modo. There is no need for an option.

You are using .LWO as an export format, aren't you? IGES doesn't work as well as LWO.

Hi Anton, could you describe a bit more about what the actual problem is that you were seeing?

Were you trying to edit the object somehow after importing it into Modo?

Vertex normals should not cause any problems if you are just importing your file and rendering it - on the contrary they actually help out significantly in that situation because they make the shading look better.

But if you were doing some kind of other steps than just simply rendering it, then you could possibly need to clear the vertex normals - but that's actually what I would consider a bug in Modo's handling of vertex normals, they should automatically clear the vertex normals and also update them in some situations where they currently do not. Hopefully this will get improved in Modo at some point so that you won't need to do any manual step of clearing normals over there.


> My suggestion would be to implement a checkbox for
> switching on and of this v-map-export even to clear things up.

I'm still not clear on what the problem was...

Under the typical circumstances of just importing a LWO file into Modo and rendering it, there should not be any need to delete the vertex normal map.

- Michael

Ok, this is absolutely cool to have vertex-maps if you are about to render a NURBS-like effect.
In contrast (only my design approach in my test project!) if you are about to render the faceted mesh which you are seeing while exporting the mesh and dragging the polygon slider then I was really annoyed (never dealt with vertex maps so far) that I couldn't get the clue, even when switching off the smooth option in the assigned material, why there wouldn't be any facets at all.
For any non-expert switching over to Modo (and case he also wants faceted geometry rendered in Modo) this would be only an comprehensible option to get a clue what's going on.

Cheers,
A

Hi Anton I see - but that's a pretty unusual circumstance to actually want to render a faceted look to your objects rather than a smooth render.


> For any non-expert switching over to Modo (and case he also
> wants faceted geometry rendered in Modo) this would be only
> an comprehensible option to get a clue what's going on.

I'm not really sure that having a checkbox for disabling vertex normals would actually solve this problem... For example if someone didn't know how vertex normals would affect their rendering it would also be easy for them to not know they had to uncheck that option (and then also adjust the material properties in Modo) in order to get a faceted render look.

I think it's just something that you need to know how to work in Modo - if you have any vertex normal map it should be deleted to get that effect.

That's a good thing to know how to work in Modo because other kinds of file imports into Modo can also create vertex normals, like importing an OBJ file for example. So if you don't learn how Modo works you could easily run into the same problems when importing other kinds of files from other programs as well.


> then I was really annoyed (never dealt with vertex maps so far)
> that I couldn't get the clue, even when switching off the smooth
> option in the assigned material, why there wouldn't be any
> facets at all.

Yes, it seems like that could be some confusing UI in Modo, where it looks like you are disabling smoothing but nothing happens.

Maybe you could report that UI problem to Luxology and see if they can improve the UI so that it won't be so confusing in that particular area. Possibly if you disable smoothing in the material it could stop vertex normals from being used or something like that.

- Michael

> then I was really annoyed (never dealt with vertex maps so far)
> that I couldn't get the clue, even when switching off the smooth
> option in the assigned material, why there wouldn't be any
> facets at all.

Because a vertex map is active, any change of the smoothing angle in the surface editor isn't take into account.
To remove the vertex map :

List / Other maps / Right click on Vertex map and choose delete.