Actually 2 questions:

1. Suppose I start with a cube object. Is it possible to select just one top edge and move that edge up ot down to make a sloped top of the cube or select the top face and resize it so the cube is now a truncated pyramid?

2. How do you guys make those cool examples embedded in your posts that show exacty what the question/ answer is?

I'm just like a kid w/ a new toy...

Thanks,

John Tucker

Hi John,


Normally instead of trying to morph a cube into a pyramid you would instead more directly draw 2 rectangles like so:



Then select them and run Construct / Loft to generate your truncated pyramid more directly:




MoI is focused more on constructive mechanisms like this where you set up your curves and then generate your model from those curves, and not so much about starting with some other solid shape and trying to squish it into your result.

That kind of squishing workflow is more prevalent with polygon modeling programs which use a different way of representing shapes than MoI does.


Although, for the case of a box you can actually squish it in MoI if you want, because it is made up of simple untrimmed surfaces. To squish it you can select it and then turn on control points by using Edit / Show pts and then select points for the top part and scale them in.

But that kind of surface point squishing approach won't generally work once you have done booleans on objects which makes them made up of trimmed surfaces. There is some explanation of that in this FAQ question here.


You mean the part that says "quote" ? To do that you write quote tags surrounding the text, like this:
<quote> stuff in here </quote>

If you mean inserting images, to do that you make a JPG or PNG image, then push the "Attachments" button and upload the image as an attachment and push the "Insert image inline" button that is available on the attachments dialog. That will then insert an <img> tag into your message which is where the image will show up. You can also just attach it and not insert it inline, that will make it show up as a thumbnail in an attachments: section at the end of your message.

The animated ones are created as animated GIF files created by a screen capture program.

- Michael

Thanks again Michael.

I did not really work too much with the V1 demo, I just kind of trusted that MOI would be a good choice based on the really good reputation it has on the web and te relatively low price. Since I just use it as a hobby, cost was a big concern. So far I am definitely not dissapointed (just the opposite in fact), but I realize I will have to re-think some of the work flow I am used to. Doing it the way you recommend makes perfect sense.

Thanks,

John Tucker

Actually, I must have been doing something wrong, I re-tried selecting the control points on, and I can easilly manipulate any simple solid. I'll try not to post too many stupid questions until I get a better handle on teh work flow with MOI.

Thanks,

J. Tucker

Hi John, well the control point editing will only work on solids that have what are called "untrimmed" surfaces.

If you have a solid that has been booleaned you will usually have a different structure to it where there is an "underlying surface" that has "trim curves" on it, and the surface control points are not necessarily aligned to the edges.

On that kind of a thing you can't generally turn on control points for it in the same way you can for a box.

There is some description about that in this FAQ item:

http://moi3d.com/wiki/FAQ#Q:_Why_does_show_points_work_for_some_objects_but_not_others.3F

So even though that works in some cases to squish a solid around, it is kind of a special case thing and not really what MoI's main workflow is set up to do.

Instead of squishing an existing thing around, the focus in MoI is much more about constructing surfaces from curves that you have drawn, it's more like a kind of "drawing" method rather than a "sculpting or squishing" type method.

MoI's method works particularly well with objects that incorporate some kinds of 2D profiles to them.

The "point squishing" or sculpting type method works better for shapes that are less mechanical and more fully organic like creatures or faces or stuff like that - for those kinds of shapes it is better to use a polygon modeling program which is focused on that kind of a point squishing workflow.

MoI is more oriented towards semi-mechanical shapes or man made things - you can build those kinds of things much more rapidly and accurately in MoI than in a polygon modeler.

So there isn't just one single method that is the best for every single kind of 3D model - different 3D systems tend to have strengths in particular areas.

But if you like that method of squishing points of a solid around, that's just generally going to apply more to a polygon modeling program's method of working and not so much to how things are done in MoI.


You should definitely watch the video tutorials available here:
http://moi3d.com/1.0/docs/tutorials.htm

Those should give you a good introduction to how MoI's general model construction technique works - you can see there that in each case the model is constructed by first drawing and arranging curves to make profiles for the shape and then surfaces and solids are constructed from those curves.

- Michael

Michael,

First off let me say that I have tried the construction lines. Along with the Straight Snap and Object Snap tools, it is nothing short of greatness. I am amazed at how well that works, much better than guides in other apps. I under stand I should expect differences in the work flow between NURBS and polygon modeling, but this is my first venture into a pure NURBS modeler. I am doing some remodeling and wanted to model a sofa with some complex curves. Only took me about 15 minuits to do my first model in MoI. I guess that tells you something about the ease of use you have built into MoI. Anyway, after reviewing the tutorials for a secomd time, I notice that in fact you can edit the solids from sweeps, revolves, etc from te control curve control points. At least for a while. After some other activities, the econtrol points only affect the curve, not the resultant feature solid. Can you tell me what specific actions lock the solid and dissasociate the modeling curve from resulting solid (I'm not even sure I am using the correct terminology here)? The command refernce does not really get into teh relationship among the various commands or the general operation or flow of MoI.

Anyway, Just let me compliment you on an your work here. I may have some additional comments and suggestions (especially regarding the UI) but I will reserve them until I have a lot more seat time. Except for one: why is the file menu om the bottom rather than the windows standard? I'm sure you have a reason.

Thanks again for your help in getting me started.

Regards,

John Tucker

Hi John, I'm glad that you are making good progress with MoI and enjoying it!

> After some other activities, the econtrol points only
> affect the curve, not the resultant feature solid. Can you
> tell me what specific actions lock the solid and dissasociate
> the modeling curve from resulting solid

The "history chain" will get broken with any operation that involves removing the object and replacing it with a new version. Most of the time this will mean operations that cut the object like booleans or trimming.

In the future I do want to improve this and make a deeper history.

For now you will mostly want to do adjustments soon after you have created a surface, before you start to apply booleans and such to it.


> Except for one: why is the file menu om the bottom
> rather than the windows standard? I'm sure you have
> a reason.

Well, one reason initially was to make the UI more friendly to tablet users. The "rest position" for a tablet will tend to be more at the bottom of the tablet (corresponding to the bottom of the screen) rather than at the top of the tablet. So having the UI along the bottom gives easier access in that case.

But also aside from that, it's a nice feeling having the top clear of UI, it allows for a more open feeling of the whole app, kind of primarily showcasing your 3D model content rather than having a window title and menu bar as the first thing you see at the top.

- Michael