For all intents and purposes, modeling wise, MODO is a tool for working with polygons. Yes, there other ways provided for generating forms somewhat indirectly, such as spline and Bezier curve patching, or working with different types of subdivision surfaces or even Fur, but the ultimate goal of those operations is to eventually create polygons for rendering/baking or export to their ultimate destination. MODO provides a variety of ways to manipulate and shape those polygons into the desired shape. Some tools manipulate polygons directly, such as the transform and deform tools, others provide means to manipulate polygons indirectly, such as the sculpting of Multiresolution meshes. There are as many methodologies to reaching a finished result as there are users, everyone has their own unique approach, but of the various styles, there are some basics to understand for MODO's way of working that will ease the overall learning curve allowing each user to reach their goal and find their own individual style.
Modeling in MODO
In any 3D modeling toolset, each tool needs to infer or be informed about several key variables in order to work properly. It needs to know its central position, meaning the location in 3D space from where the desired effect is applied. It also needs to know its operational axis (its orientation), and finally it needs to know which portion of the scene is going to be affected and by how much. In MODO each of these variables has been extracted to its own operational layer, offering each as an individual building block, such as Action Centers and Falloffs. All the tools in modo are made up of these building blocks and understanding how each part contributes to produce the final result is an important step in getting the most of the modo toolbox. Users can also assemble these blocks to make their own custom tools via the Tool Pipe, providing a flexible and really powerful way to work.
Components versus Items
One of the areas that is often confusing to new users of MODO are the various selection modes. When modeling, users work in the three component modes -'Vertices', 'Edges' and 'Polygons', this is where the actual geometry is created and shaped. 'Items' mode is useful for positioning modeled object in a scene and is a necessity of Animation in MODO proper. When in any individual selection mode, only selections of that type can be made. The important distinction is that when editing an Item, users are editing the layer itself (think of it like a container), while editing a component is editing the contents of the layer (what's inside the container). Modifications made in the Vertex, Edge and Polygon modes happen around the Center point, while transforms applied while in Item mode move the entire item, including its Center point.
Interacting with MODO
Interacting with MODO itself is done mostly through the manipulation of the mouse, taking advantage of all three buttons and the scroll wheel (some may prefer a trackball or tablet, both typically have functions that can be remapped to mimic the options available on a mouse). Mouse button activity is supplemented by keyboard commands, which are at times used in unison with the mouse. This can take some getting used to (see Mousing Standards for more information). Given that MODO is a 3D application that users interact with in a 2D fashion, this may at times feel awkward, but produces the most predictable results given today's technology (Hey, where's my 3D monitor and force feedback gloves?).
Users are encouraged to read through the entire interface section of the documentation; familiarizing oneself with the many viewports, tabs and panels will help in working in MODO. Nothing kills the creative impulse more quickly than fruitlessly searching for some often used tool or function. The organization of MODO is designed to reduce this as much as possible. Main functions are organized as Tabs across the top, such as Modeling or Sculpting. When in any of these areas, only the tools necessary for the task at hand are provided, streamlining the process. This way of working also makes it easy to jump in and out of tasks easily, providing for a comfortable non-linear workflow. Users can model, UV map, sculpt and then model some more with very little worry that one process will have a negative affect on the others. In fact, a non-linear workflow is encouraged in MODO. Users should be adjusting and tweaking along the way toward the final result. This is meant to eliminate a lot of the guess work and surprises traditionally associated with creating in '3D'.
Using Tools
To use any tool to perform an action, users must first left mouse button (LMB) click on the tool button or menu option. For one-shot commands, such as 'Delete', 'Fit' or 'Hide', that is all that is necessary to produce a result. For interactive tools, like 'Move', 'Rotate' and 'Bevel', this makes the tool itself active but it isn't yet acting on anything in the scene. At this point the user can modify the default values of the tool in the Tool Properties panel, and then press 'Apply' to act upon the target, OR LMB+click in the 3D viewport sets the tool in interactive mode. This action draws the appropriate tool handle within the viewport. Now the Property values can be interactively adjusted by LMB+clicking and dragging on any of the available tool handles (handles will change to a yellow color to show they can be adjusted) constraining the action so specific axes, or by 'Hauling' which is the act of LMB+click dragging the mouse pointer left/right or up/down within the viewport away from any tool handle, allowing users to modify multiple axes at once. When the desired result for a tool is achieved, users can simply drop the tool by pressing 'Q' key to finalize the application of it. Once a tool is dropped, interactive editing of tool attributes is no longer possible and the action of the tool is fixed into the target geometry.
Work Plane
Users should understand that actions don't arbitrarily happen in 3D space within a viewport. For example, when creating points, the individual vertices are created at the intersection of the 'Work Plane' and where the user clicks in the viewport, providing predictable and repeatable results. Understanding the Work Plane and its functions is important to understanding how MODO works. The Work Plane is the light gray grid that is visible in any viewport. In a perspective view, users may notice that the grid will change position; this is the Work Plane orienting itself toward the user, trying to stay as close as possible to parallel with the viewport window, while remaining aligned to the nearest axis. Users can also modify the Work Plane to a fixed arbitrary position, based on a component selection. This temporarily orients the entire MODO universe to align with that selection, so all functions now work in relation to the Work Plane making it easier to perform task that would be very difficult otherwise. For more information regarding using the Work Plane, please reference that page of the documentation.
Action Centers
When performing any action on a selection, the position of the center of origin and the axis orientation of the tool handle itself has a dramatic effect over the result when applied. Yes, users can orient the Work Plane to suit many situations, but constantly modifying the Work Plane would get tedious, so MODO has what are called 'Action Centers', automatic combinations of center positions and axis directions for tools. There are a variety of options, based on different criteria; some are oriented to selections, some to a viewports orientation, while others are based on fixed positions, like the items center (0,0,0). Action Centers often packaged with tools to provide specific functions. Take for instance the Flex tool, this combines a rotation tool, with an action center that orients itself automatically to the selection border making it easy to pose characters. Understanding Action centers are necessary to a fluid experience with MODO, it is recommended users reference the Action Center page for more information on working with them.
Falloffs
Ordinarily, when performing an action on a selection, the application is uniform across the selection area. Falloffs provide a means to vary the strength of the action across a given area. Once activated, all of MODO's tools respect the falloffs and apply themselves appropriately, opening up a variety of option that would be incredibly difficulty to reproduce otherwise. When enabled, a Falloff will snap to a selection if a tool is currently active, scaling to fit within the selections bounding box, making them incredibly easy to apply and use. Falloffs can also be packaged along with tools, and often are. They are the basis of the many deformation tools - Rotate combined with a linear falloff produces the Twist tool, Move combined with the same falloff produces the Shear effect. Falloffs may appear simple, but wield an incredible amount of power when working in MODO. For more information on using and applying Falloffs, please reference that section of the documentation.
