Hi Guys,
I'm a complete novice looking to do some modelling of Armoured Vehicles.
I like the clean look and UI of MOI alot, but currently understand very little of how I can use it effectively.
So rather than ask for recommended Tools, that'd be plain rude.
Instead I'm simply asking the more experienced folks whether they'd use MOI for this?
Assuming I can put the time in to learn, am I going down the wrong path, so to speak?

Hopefully, not too much of a dumb question.

Cheers
Gav.

Hi Gav, yeah MoI is a good program to use for modeling armoured vehicles.

You follow the same general kinds of steps that are shown in the introductory tutorials here:
http://moi3d.com/1.0/docs/tutorials.htm

just that you'll have some different styled shapes that you are booleaning together, like you'll have more blocky chunks instead of long smooth pieces.

But if you follow along those video tutorials linked to above it should give you a good overall introduction to the basics of NURBS modeling and how you build basic shapes in MoI. You build more detailed shapes by spending more time assembling more and more basic shapes together.

There are quite a few people who use MoI to do this kind of modeling, here are some links for you to check out:

http://moi3d.com/forum/index.php?webtag=MOI&msg=3297.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=2965.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=2286.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=2122.1

http://moi3d.com/gallery/viewitem.php?id=236
http://moi3d.com/gallery/viewitem.php?id=67
http://moi3d.com/gallery/viewitem.php?id=23


Those were just some examples from looking through the gallery and also just searching the forum for the keyword "Tank".

- Michael

Hi Michael,
Thanks for the rapid reply.

Thanks for the links - I had seen all but 2 I think, but was really curious as to whether those sorts of guys had used MOI for reason, or simple because they could.
Being honest, my biggest problem is my lack of skill and knowing how to move through the stages and what makes sense when.

I struggle with some of the editing and grabbing vertices and moving them seems to make more sense at the moment, my previous 3D foray was 15 years ago at College and all meshes - NURBS still have some work to do in my head :-).

Anywho, I've really enjoyed using the trial so I'll push on and see where I get with my ideas.

Cheers.
Gav.

Hi Gav, did you check out the tutorial videos that I linked to above?
(http://moi3d.com/1.0/docs/tutorials.htm)

So one thing you may notice when viewing those is that there is no time where any surface in those videos are edited by grabbing surface vertices and moving them around.

There are points edited but they are on 2D curves, then you use those curves to construct your shapes to produce the result.

In NURBS modeling you mostly generate surfaces from profile curves in that same way instead of directly manipulating the surfaces like you would in a polygon modeler.

This NURBS "2D curve driven" type approach tends to work really well for man-made or mechanical type shapes which tend to be made up of blueprint-like profile curves that define how the shape should look like.

When you get into more very organic shapes like a creature or monster head, then things like that are not well defined just by a 2D profile curve and so for things like that you do want to use mesh vertex modeling which is more suited for direct surface tweaking.


But when your design is well defined by 2D profiles, it tends to be much quicker to do the setup work in 2D instead.

One way to compare it is that NURBS modeling is kind of more like a construction and drawing approach to building the model, while the mesh vertex modeling is kind of more like sculpting since it is pushing a bunch of vertices around in 3D.

But setting things up in 2D when possible can be really quick and easier to control, that's why for things that are defined by profile curves it will usually be better to make those with NURBS rather than with polygons.

The other part that works well with NURBS is that booleans are something you use as a basic modeling tool, while in polygons it is something that you usually try to avoid. So things like holes or cut away pieces are very suited for NURBS modeling.


Make sure to go over the videos a few times, and maybe try to build the same thing by following along.

If you get stuck with a particular model, please post the model here and I'll see if I can give you some tips on how to better approach it.


Also here is a recent thread where I was helping someone switch to a more "NURBS construction" mindset instead of a polygon mindset, you may want to look it over:
http://moi3d.com/forum/index.php?webtag=MOI&msg=3321.1


One kind of key thing is that with NURBS modeling you will often times want to draw a slightly extended model that you then cut with other pieces to form the final shape. You generally want to incorporate booleans and cutting as much into the modeling strategy as possible.


- Michael

Hi Michael,

Yeh, I've had a good look at quite a few of the videos, yours and the Ferrari build in particular.

"So one thing you may notice when viewing those is that there is no time where any surface in those videos are edited by grabbing surface vertices and moving them around."
Yep, and that's where sometimes I've had to stop and think 'what now' :-).

I'll take your advice and try and recreate and few of the examples, and read check out the other posts you mention.

"If you get stuck with a particular model, please post the model here and I'll see if I can give you some tips on how to better approach it."

Will do - cheers.

"One kind of key thing is that with NURBS modeling you will often times want to draw a slightly extended model that you then cut with other pieces to form the final shape. You generally want to incorporate booleans and cutting as much into the modeling strategy as possible."
One of those things that time and experience will show I guess.

Thanks.
Gav.

Hi Gav,

> Yep, and that's where sometimes I've had to stop and
> think 'what now' :-).

Well, usually it is just repeat more of the same process - draw in some new profile curves, create some new solids from those by whatever method is suitable for the shape, like extrude, sweep, revolve, etc... then combine those new solids with other ones by booleans.

Also instead of creating a solid sometimes you will draw in curves and use the curves to cut away pieces of the solid to make a new shape.


> One of those things that time and experience will show I guess.

Yeah, kind of - one thing that may help is to imagine more about how some part would be manufactured.

When some kind of steel part is manufactured by machining, it does not get built in a factory by some machine pulling vertices around, instead there may be things like drills that cut away material from some stock or cut holes in things and so forth (of course there are quite a variety of different manufacturing methods, but that may help with some ideas).

So if you want to have a hole in something, with NURBS you want to model the main piece without the hole first, and then make the hole by cutting the object with a boolean operation. That's instead of trying to make holes by something like moving a bunch of vertices to kind of follow a path around the hole.


It's definitely a very different approach from polygon modeling, but actually that's why it is useful! If it just behaved the same as polygon modeling then there would be no benefit to you to use it instead of polygon modeling. By it having a different approach, that makes it have different strengths and weaknesses and if you use it situations that leverage its strengths that's when you can save a lot of time.

- Michael