Summary

In this tutorial, I will try to explain all options available when modeling in the vertex sub-object. It may look like just a long list, but I'll will try to explain when a certain modeling action in the VSO is useful and give examples of when you could use it.

If you haven't created an EP (editable poly) yet, then do so now, by creating a new primitive and converting it to an EP by selecting it, right click, 'Convert To:', 'Editable Poly'. Then go into sub-object mode (Ctrl + B) and to the Vertex Sub-Object (Insert, or click the plus and select 'Vertex'). Then, if you haven't done it yet, open the modifier tab. What you should look like right now:

Under this you can see all the options you have in the VSO.

Selection

Under this roll-out you can switch to other sub-objects, as indicated by the five icons, right now the vertex one is higlighted since we are in that mode. While we are in this mode, notice how in your viewport all the dots of your model are shown more clearly, they may have become little plus signs, or small blue dots for me as seen on this screenshot (switch between wireframe and smooth + highlights of your viewport by pressing 'F3'):

So now you could select one, or more vertices by selecting them and then moving (shortcut: W) them. Selecting multiple vertices can be done by pressing Ctrl, deseleting vertices can be done by pressing Alt and then clicking the ones you don't want. This is always the case in Max: Ctrl adds to your selection, Alt subtracts it from your selection. Moving can be done by using the XYZ euler , which works very intuitively.

This is all basic knowledge and you really should be aquainted with it before continuing with this tutorial.
Also notice the little line: 'Vertex 6 Selected'. This may seem insignificant, but it's not. It can be extremely helpfull, since sometimes you have, without knowing it, or by accident created additional vertices which are at the exact same position as other vertices, so you don't see them, but they do affect your model, for instance when using MeshSmooth. With this line you can see that, since you could drag select certain parts of your model and expect a certain number of vertices and then when this doesn't match the number shown, then you know something is going on! I'll show an example under the Edit Vertices Roll-Out.

So first up:

Shrink: This is an option to make your current selection shrink (unsurprisingly). Keep in mind when using shrink, that it needs a 'hole' in your selection to be able to shrink. For instance when I select all the vertices of my model and then press 'Shrink' nothing happens. It needs a start, so select all vertices then deselect (Alt) one and then press shrink to see what happens: all the adjacent (connected by a single edge) vertices to the one you just deselected, are also deselected.

Grow: The inverse of shrink and also works in the same manner: if you haven't selected anything then there is nothing to grow from and it won't do anything. But select one vertex, press 'Grow' and see that all adjacent vertices are selected. This I use more often than shrink, usually when I have a large model but when the model is made up from separate parts: grow doesn't continue growing from one loose part of a model to another. When there is a physical gap, so no connection between two parts in the form of an edge or multiple edges, then grow will stop there (but of course will try to grow until one whole part of the model is selected).

Ring and Loop: This is 3D Max logic at it's best: they're there, but you can't use them. They'll be available in the Edge sub-object (and be very very useful).

Soft Selection

Before you can use Soft Selection, you click the radio button 'Use Soft Selection', only then will all the parameters become available. Up the value of Falloff until you see the color of your vertices change: the color indicates how much influence it recieves from your originally selected vertex/vertices. Soft selection is exactly the right description of what it does: you select certain vertices, but softly, so that when you move those vertices is has a certain feedback on vertices which you didn't select. They kind of drag along with your originally selected vertices. Try it out and play with the Falloff, Pinch and Bubble parameter to get a feel of what it does. Shade face toggle we will come back on later, in the tutorial about the Polygon Sub-Object.
I personally hardly ever use it, mainly because it has a vagueness and non-controllableness that I don't like. Especially when modeling technical and detailed stuff it's in my opinion useless. On the other hand, soft selection can be extremely handy for organic modeling!

Deactivate the Soft Selection again.

Edit Vertices

Remove: Not really sure why on Gods green earth they made a button to do this, but ah well. Select vertices, press this button and they are removed. I have seriously in all my years of modeling, never ever used it. Just select what you want to delete and then press... Delete! Amazing, but true.

Break: When you perform this on selected vertices it breaks them loose from the current model, in a copy kind of way. :) It creates a number of vertices which is equivalent to the number of edges comming together in your original vertex. I'll show what I mean in the next three images (with the text shown in the selection roll-out):

Obviously something has happened, since we went from one vertex to three. When you move each one of the three vertices away from it's original position you can see what has happened:

They are all independent.

Extrude: This one works a little differently from the buttons we have so far, since we can either do some extruding manually (press the button) or do it by the numbers (press the little window next to it). Try extrude on a single vertex (either way, manually or by the numbers) and see what happens. You get a spike from the original vertex. I am not quite sure what to make of it and when to use it. Maybe, now that I have fooled around with it for a bit, I can see a purpose for it. Extrude creates something, and as mentioned in the introduction, I deem this sub-object for shaping mostly.

Weld: Ah! Weld, now we're talking. This is something I use very, very often. It melts two or more vertices together. So if you would have performed a break operation for instance and then selected the three newly created vertices and then pressed weld then the Break operation is undone in a non-undo-pressing kind of way. Here also there is the manual and technical version. In the by-the-numbers one you can set a threshold which is effectively a sphere around your selected vertices: all vertices within the sphere of influence of an other vertex will melt together. And they will melt at the average of their positions. The sphere cannot be drawn manually, so by pressing the button you apply welding with the threshold as set in the by-the-number window.

Target Weld: The brother of weld, but used more often by me. With this you can drag one vertex, in your viewport, to another one and it will melt the first onto the other, without any averaging of positions. Click it, then select a vertex of your model (click and drag, notice the dashed line!) and drag it to another vertex: congratulations, you have target welded! \o/ It is extremely handy for cleaning up your mesh or correcting certain modeling operations (double chamfers for instance, but I'll come to that in Tutorial 5 about Modeling Techniques).

Chamfer: Chamfer is in this sub-object almost the same as extrude (try for instance an extrude with height = 0). But anyways: chamfering. Chamfering is one of the essentials in polygon modeling, yet not in vertex sub-object. But what it does is create an additional face. Here I selected one corner vertex and was in the middle of chamfering it:

As you can see, it smoothens it out a bit and creates a new, triangular shaped, face.

Connect: This connects two (and only two, not more, not less) selected vertices, by making an edge that connects them. But only if the two vertices are part of the same face. You still with me? No? Good, since it's totally useless.

Remove Isolated Vertices: It removes vertices that have decided to be alone. :) You would have to seriously be doing something weird to create a single or more vertices that aren't attached to anything. Something like this for instance (it would remove the one indicated by the arrow):

Remove Unused Map Verts: I really wouldn't know. But, quoted from the manual:
Certain modeling operations can leave unused (isolated) map vertices that show up in the Unwrap UVW editor, but cannot be used for mapping. You can use this button to automatically delete these map vertices.
So there ya have it. I have never even gave it look, up until today. PS: You see how Dicreet (the makers of Max) are toying with us here? Tsk, using 'verts' instead of 'vertices' because else it wouldn't fit in the tab! PAH! :)

Edit Geometry

Create: Creates a vertex at the position where you click. This is for hardcore modeling only.

Collapse: Mighty handy tool, which resembles welding: select the verts you want to 'collapse' and press 'Collapse'. Then all selected vertices will collapse into one single vertex at the position, which is the average of the original bunch.

Detach: Don't ever use Detach in the VSO. Ever. It's just useless. It cannot be what you want to do. Believe me.

Hide Selected / Hide All / Hide Unselected: I advise not to use this in any sub-object, but only on complete models / meshes.

The rest of this section will be covered in the Polygon Sub-Object tutorial, since it's the same for all sub-objects and because there is some small differences concerning selection of a part of your model and then applying one of the operations available here and that difference is best explained in the PSO.

The last three roll-outs (Vertex Properties, Subdivision Surface and Subdivision Displacement) I don't use. Ever. They may be handy, but I have lived without even giving them a single look.

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