Modo Walkthrough: Primitives 1 – Cube and Sphere

It has been a long time since I last wrote on this site. Having spent the last few years concentrating on my full time job, I am now in a position where I have enough time to return to working with 3D and incorporate it into my job.

As a result, I will be working my way through and documenting my chosen software, Modo, to get a deeper understanding of the program, and giving myself a full refresher on 3D in general. Throughout this process, it is inevitable that I will use other resources on the web, for example, youtube, the modo manual etc. Where applicable I will post the resources at the end of the post. While this process is largely for myself and my own learning, I hope that presenting it here will help at least someone else at the same time.

Please note that having spent years in Lightwave working with a quad view, I prefer to use the “model quad” functionality rather than a single window with the work plane.

The best place to start looking is at the primitives. While most people of course know what these are and how to use them, it is still important to cover them and all of the menus that are associated with them. The primitives can be found in the top right corner of the Modelling tabs. There are a total of sixteen options, two of which will be covered in this first section in order to keep the post length down. The vector/pen options and text will be covered in their own section.

The primitive tools in Modo
The primitive tools in Modo

Primitives with the small arrow in the bottom right corner can be held down for further options.

Pressing the triangle for more primitives
Pressing the triangle for more primitives

The list of primitives available are: cube, sphere, ellipsoid, cylinder, capsule, arc, cone, torus, tube, and solid sketch.

To select a primitive, click on it then drag out the rough dimensions in the quad view using the handles in the appropriate panel to select the desired size.

A basic cube in the quad view, drawn out by using the handles to adjust the size
A basic cube in the quad view, drawn out by using the handles to adjust the size

There is a menu to the side of the frame that allows you to manually input all of the primitive’s variables which is contextual to each different shape. However, some of the variables are the same for all of the primitives, e.g. position, size, segments.

The primitive variables menu
The primitive variables menu

This will be covered only once, but the individual variables will be covered for every primitive.

Variables common to primitives:
Position
The position parameters determine where the primitive will be placed in open space, with 0,0,0 being the centre.

Size/Radius
The size determines the size/radius of the primitive.

Segments
The segments option allows more segments to be added to each side of the primitive. For example, taking a cube as an example, adding extra segments to the sides divides the cube into more polygons.

A cube with four segments on each side.
A cube with four segments on each side.

This is very useful when starting a model as it reduces the need to immediately subdivide/cut/bevel etc. It also divides the segments up equally.

On primitives like the sphere, this determines the number of horizontal cuts there will be.

32 segments vs 16 segments
32 segments vs 16 segments

Sides
This determines how many segments make up the primitive, it is typically used for round objects, for example, the sphere or the ellipsoid

Axis
The axis option determines which axis the radius will be projected on, and therefore changes the direction of the base and the top.

Make UVs
This option makes an automatic UV map for the primitive. This is fine if you want to just use the primitive, but if you start manipulating the shape you are better off making your own.

Min/Max X, Y, Z
This value determines the minimum starting position of the primitive in the world, and the position where it ends. This is another way of amending the size of the primitive where the start and terminus are known.

Cube specific options
Radius and Radius Segments
The radius variables allow for the cube to be rounded off on the edges. The radius value determines how much of an inset there will be for the rounded off edge, radius segments determines how many cuts there will be in the additional geometry. Sharp determines how round the edges can be, i.e. the angle of the rounding off, by adding extra geometry at the edges.

Not sharp vs. sharp radius
Not sharp vs. sharp radius

Sphere specific options
Sphere Mode
This option set allows you to change the way that the sphere is constructed

The three sphere modes
The three sphere modes

Globe is the default and creates a regular sphere that represents a ball, quadball creates what is essentially a subdivided square, tesselated adds a sphere that is composed of triangles and quads, and looks like the sort of thing that you might sew together until you increase the subdivision level.

Subdivision level
This lets you choose the level of subdivision that you want to use, higher numbers equate to smoother surfaces but a larger polygon count.

Polygon Type
The choice between face, subdivs and Catmull-Clark lets you choose which algorithm you use to smooth the mesh. Note that face is the normal, non subdivided model.