Hi all

Ok, so I keep finding myself wanting the same feature/command, so I thought I'd ask, in case it can be done already, or in case Michael would be willing to create one :D

So what I want is a command that can inset a shape (often the original shape) into a surface, or multiple surfaces...

I'll (manually) create some examples, so you know waht I'm talking about!

1) So you could inset a surface using the surface's own shape:


2) You could inset multiple surfaces, using their own shape:


3) You could inset one or more surfaces using a custom curve shape:


What do you think?

I think it'd be so handy! I'd use it all the time!

I think parameters would be something like:

- Inset width (the distance from the edge to begin the inset)
- Inset depth (the depth of the inset)
- Flip (to make it outset, instead of inset)

Hi NightCabbage, that is actually something I've been thinking about recently and I have some ideas on how to add that in the future.

In the meantime though you need to use a combination of tools (like Offset, Extrude, and Booleans) to create that kind of stuff. See here for some examples:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2088.5

- Michael

Thanks Michael

I'm glad to see you're thinking about adding that feature - I'd use it on every model I made :D

Also, that thread that you linked to is interesting! At the bottom, you mention "multi planar extrude" etc.

Which is exactly what my next question was!! I'd even made the following picture!!



I called it "thicken" because I couldn't think of another way to describe it :)

THere would be some slightly tricky things for MoI to figure out what to do in certain circumstances, but it would be a very handy tool!

Hi NightCabbage, also there is an existing command called Shell which is related in several ways to the first 2 ones that you show.

If the piece you want to perform the inset on is a simple solid and not part of a large complex piece, then you can use Shell to help speed up those cases.

The way it works is like this:

If you have solid piece like this:



Select the faces that you want to have as openings in the shelled result, so in this case select these 2 faces:



Now run Construct > Offset > Shell, and enter a wall thickness value.

That will create this result:




Note that it is pretty close to what you are asking about - but it has more of a fully hollow shape rather than an indentation. But it has done a lot of the work already.

Now you can pick the inside bottom 2 faces like this:



Use Copy / Paste to duplicate them, then run Shell on those new surfaces to thicken them into a solid, you will need to set the Direction: Flip option in Shell to make them go in the proper direction.

That is the other use of shell, to thicken surfaces into solids - with that surface thickened into a solid, it is now a plug which fills in the hollowed out area, so you can now select the 2 solids and use Boolean Union to make the final result.




That sequence could be useful for doing some shapes like this pretty quickly right now.

- Michael

lol, sadly my shell attempt wasn't quite as successful as yours :)



Any idea what I'm doing wrong?

After doing the shell to make the deep inset (which works fine), I have copied and pasted the 2 faces. Then I have run Shell on them, with thickness 3 and flip.

Hi NightCabbage, sorry I was writing my post above while you posted your other one.

> I called it "thicken" because I couldn't think of another way to describe it :)

In MoI it is called "Shell", and it is available under Construct > Offset.

Check out some of the illustrations on it here:
http://moi3d.com/1.0/docs/moi_command_reference7.htm#shell

It's very worthwhile to spend a bit of time browsing the documentation - it has a lot of illustrations in it that show what kinds of commands are available:
http://moi3d.com/1.0/docs/moi_command_reference.htm


However, Shell will have some difficulty thickening pieces made up of more than one surface, if their edges do not meet at simple angles. So the example you have there where the top has an angled slice on it will not shell properly, but if you do it on a simple straight piece like this before cutting the angled part, it will work, like so:





Then cut the angled top off after it has already been thickened.


You can be better off doing more stuff with curve profiles when possible though, so for example if you want a thickened object it can be a better idea to thicken your initial curves first by using Offset on them (in v2 there is a new "cap ends" option for offset to produce a thickened outline curve very easily), and then extrude that and you will have a thickened result right from the first extrusion.

- Michael

Hi NightCabbage,

> Any idea what I'm doing wrong?

Hard to say without examining the model file directly. Can you please post the 3DM model file (before shelling it) so I can check it out?

But it kind of looks like you may need to do an extrusion rather than a shell for the filling piece, because your shape is based on an extrusion rather than an offset.

Note that the angle used in my shape is different than your most recent one in this area here:



Your new one goes straight upwards, unlike your original one which was shaped more like mine I think?

- Michael

> Your new one goes straight upwards, unlike your original one which was shaped more like mine I think?

Ah, yes, this is true :)

Though does this mean that it's harder to "inset" some shapes than others?
ie. the second one I made

Also shell - haha it's working quite well with my random shapes now, however for some reason, the last time I tried it (to "thicken" something) it didn't work properly - I'm not sure why! If it happens again I might post the 3dm file...

Thanks for the help and patience Michael - as always!

<3

Hi NightCabbage, no problem!

> I'm not sure why! If it happens again I might post the 3dm file...

It can easily run into difficulty when thickening pieces made up of more than one surface, if the surfaces do not all attach to one another in a very regular angular pattern.

In cases like that you may need to separate the model into individual surfaces and thicken those surfaces - the thickening of a single surface should not run into the same kinds of difficulties.

Hopefully in the future it will be possible to thicken multi-surface objects more easily than what is done currently, but it will need a pretty big upgrade to the shelling component in the geometry library that MoI uses which is licensed from another company. I do have a request in to them with several examples to ask to improve this area, I'm not sure when that will happen though.


Shelling a solid works in a different way than trying to thicken a surface, so sometimes instead of thickening a surface you may want to finish the surfaces into a basic solid, then perform the shell on the solid. The sheller is more able to make clean matching pieces when there are side walls available to cut pieces with.

- Michael

Hi NightCabbage,

> Though does this mean that it's harder to "inset" some shapes
> than others?
> ie. the second one I made

Probably that is true (that some things will be harder than others to inset with this method), but actually in the second one you made you just should use Extrude for the second step to build the plug pieces, rather than Shell for that step.

By default extrude will make faces extrude along their own face normal, use the "Set dir" option and click 2 points vertically to make the faces extrude along the vertical direction and then you will have your plug pieces.

If you have a larger solid and you're trying to inset just one small area of it, you probably won't be able to use the method I showed here because the shell will work more on the whole object. For something like that you'll need to work at kind of a lower level, doing Offset on the edge curves, then trimming or extruding, the kinds of steps that were shown in that previous link above.

- Michael

Awesome! I just found out a cool way to do insets :)

You have the original shape, and you do a project of the curve shape you want to be inset onto it.

Then you network it, and extrude it into a solid.

Then boolean subtract it out.

Easy :D

One thing I find about MoI - it has so many "hidden" features!
eg. Boolean Difference can also be used as a "slice" tool

I had sorta asked Michael for this when I had mentioned to him that I had wished for a traditional Bevel and Extrude command for some faces I was working on.


Hopefully we'll get something like this in MoI soon - it would make my panel work so much faster and easier for sure!


-Will

.

I had an idea that I just had to try:



Tends to work best with blocky shapes though, where offsetting does not have problems.

- Michael

That looks very cool Michael. What happens on trimmed curved surfaces?

Side note: I just noticed the "Set Flat Direction" option in the sweep flat command. This is cool too.

That was not yet possible with the offset shell function?

Hi Pilou,

> That was not yet possible with the offset shell function?

Shell is related but not the same - shell hollows out the entire object.

Like for example with this selection:



Shell hollows out the entire object and leaves those as openings, producing this result:



Shell produces a "thin wall" object.

An Inset on the other hand, does not go through the whole object and instead produces a result that is localized to those faces:



- Michael

Wow!
Great Michael.
eric

Hi Burr,

> That looks very cool Michael. What happens on trimmed curved surfaces?

It can depend on the shape, there can be difficulties in the offset calculations in a lot of cases. Also currently the pieces being inset must be bounded on all sides by sharp corners.

But there are a lot of trimmed curved surfaces that will work as well, like here is a sweep that has a hole booleaned out from it:








- Michael