Using primitives (simple shapes such as cubes or cylinders) to create a basic "placeholder" version of the model gives the animators something to work with while the model is being completed. Depending on the project you are working on, getting a character approved can take time and could leave the animators waiting around for you, which in the long run will put them behind schedule. Generating this quick model will mean the animators can get to work early, transferring the animation to the final model at a later stage. Not only does this facilitate the workflow, it can also pinpoint any potential problem areas with the character's proportions
Basic Limb Creation
Using the file Kila_Start.mb that we have established, we can create some basic shapes and scale them to fit our character.
Load the file named Kila_Start.mb. Start by switching to the front view panel, and create a cube. To do this, go to Create > Polygon Primitives > Cube and open up the Polygon Cube Options dialog box (Figure 2.18). Make sure Width, Height, and Depth are all set to 1; then click the Create button.
Figure 2.18. Polygon Cube Options settings
Select the newly created cube; this highlights it in green, and a new manipulator should appear. (If this doesn't happen, press W to get into move mode, or click the Move tool in the toolbox to the left.)
Take a look at Figure 2.19, which shows the four main manipulators; from the left, they are Move, Rotate, Scale, and the pivot point manipulator.
Figure 2.19. Move, Rotate, Scale, and pivot point manipulators
Each manipulator has four directions of movement or rotation, displayed in a particular color:
Red moves or rotates around the X axis (left and right).
Green moves or rotates around the Y axis (up and down).
Blue moves or rotates around the Z axis (forward and backward).
The yellow box/cube/circle moves or rotates the object relative to the camera's view.
The use of each manipulator is pretty self-explanatory except for the pivot manipulator. This will allow you to move the pivot point on the selected object. You can access this by pressing the Insert key.
You can alter the size of a manipulator by using the + and keys.
Using keyboard shortcuts is a good way to work more quickly. For the manipulators, use W to switch to move mode, E to rotate, and R to scale.
Using the appropriate manipulator, move, rotate, and scale the cube until it roughly fits Kila's left thigh (Figure 2.20).
Figure 2.20. Thigh creation, front view
Note that it is important that you not freeze the object's transformations at this stage; this would reset the object's axis, making it more difficult to scale. Figure 2.21 (left) shows the axis as it should now be at this point in the procedure. We can quite happily scale this object; it will scale around the correct axis. On the other hand, Figure 2.21 (right) demonstrates the axis if it were reset. Scaling this object now would deform it incorrectly, making it difficult to achieve the desired shape.
Figure 2.21. Do not reset the axis; it should be as shown on the left.
Viewing the Geometry
Open up a view panel's Shading menu will reveal all the ways you can view your geometry as you work (Figure 2.22).
- Wireframe (key 4) Displays the edges of all the geometry in the view panel.
- Smooth Shade All (key 5) Displays all the surfaces as smooth-shaded.
- Smooth Shade Selected Items Displays the selected objects' surface as smooth-shaded (not shown in Figure 2.22).
- Flat Shade All Displays all surfaces and meshes as flat-shaded, faceted objects.
- Flat Shade Selected Items Displays the selected objects' surfaces as flat-shaded/faceted (not shown in Figure 2.22).
Figure 2.22. Various ways to view your geometry in Maya
Viewing the Geometry, continued
- Bounding Box Shows the objects in the scene as boxes. This is mainly used to speed up Maya when you're navigating complex scenes.
- Points Displays only the points (vertices) of objects in the scene (not shown in Figure 2.22).
These last two are in the Shade Options submenu:
- Wireframe on Shaded Combines the smooth-shaded and wireframe views.
- X-Ray Shows all objects as semitransparent.
There are other options to be found in the other menus that allow you to alter the lighting and so on, but we will discuss those as and when we come to use them later in the book.
At this stage, you may find it easier to work in X-ray mode because it allows you to see through the geometry in the scene.
When you're happy with the front view, switch to the side view and again manipulate the cube until it fits inside the thigh on the image plane (Figure 2.23).
Figure 2.23. Thigh creation, side view
At this point, you may wish to taper the lower part of the cube so it fits Kila's thigh better, coming in slightly at her knee. The easiest way to achieve this is to work directly on the vertices. At the moment, you are working in Object mode, meaning you are selecting, editing, and manipulating complete objects. Vertices, like polygons, edges, and UVs, are all components of objects, so to edit components we need to switch to Component mode. There are a number of ways to do this:
Right-click the cube itself. This will display a marking menu with options for opening up various components of the object for selection.
Look at Figure 2.24 (top). I have highlighted the Select By Component Type button in the status line. Clicking this button will switch to Component mode, and the buttons to the right will change to represent the various components you can select.
Figure 2.24. Switch to component mode (top) and the selection type buttons change (bottom).
Pressing F8 will toggle between Object mode and Component mode. You can then select the component you wish to edit via the marking menu or the buttons in the status line.
Switch to Component mode and open up the vertices for editing. You will notice that the box's outline turns blue and the vertices are now colored purple. You can select the vertices at the bottom of the thigh and scale them inward, so that they fit nicely around her knee. Do this in both the front and side views.
To go back into Object mode, press F8, or you can right-click to bring up the marking menu and select Object Mode.
Sortcut Keys for Editing
F8Toggle Component/Object mode
Continue using this method, creating basic cubes and manipulating them until you have Kila's left side completed; just concentrate on her limbs for now. You should end up with something like Figure 2.25.
Figure 2.25. Basic left arm and leg created with cubes
Create the Right Side
Kila's right side will require much less effort than her left. With this model, we can simply mirror her left limbs to create her right side.
To do this we will group the current geometry. Grouping objects serves two purposes. First, it keeps the scene nice and tidy, making it easier to work with and navigate among the objects. Second, it allows us to manipulate a series of objects at the same time and with the same pivot.
When grouped, all the selected objects will be placed under a group node. This is the parent, and the objects are children. Whatever you do to the parent will be reflected in the children.
When objects are arranged in a group hierarchy, you can move up and down the chain using the arrow keys. The up and down arrows will "pick walk" up and down the chain. The left and right arrows will cycle through the objects on a particular hierarchical level.
Select the geometry you have created for Kila's left arm and leg, and go to Edit > Group (or press Ctrl+G/Cmd+G). This groups the objects, placing the pivot for the group in the world's center.
When selecting objects in your scene, remember these key-click combinations: Holding down Ctrl will remove items from the current selection. Holding the Shift key will toggle the items between selected and unselected. Holding down both Ctrl+Shift will add items to your selection.
Create a duplicate. With the new group still selected, go to Edit > Duplicate and open up the options. Set the first input box next to Scale to 1 (this will mirror the duplicated geometry across the X axis). Also, make sure Geometry Type is set to Copy and Group Under is set to World. When you're done, click the Duplicate button.
You now have two arms and two legs in the scene (Figure 2.26).
Figure 2.26. The character with both sets of limbs
Finishing the Head, Neck, and Torso
To finish Kila, we need to create a head, neck, and torso. As before, we will use simple cubes for these. Create four cubes and manipulate them until they represent the neck, head, upper torso, and lower torso (Figure 2.27).
Figure 2.27. Cube placement for upper bodyfront and side views
Divide the torso under the rib cage to give it a little more flexibility when it is animated.
She's not much to look at, really, but this Dr. Who reject will be quite important in getting your characters animations started. All that is left at this stage is to clean up your scene and the History list.
Select all the geometry that makes up your character and, as before, press Ctrl+G/Cmd+G to group everything into a nice tidy group. This should be named group3.
Open up the Outliner (Windows > Outliner), which displays the contents of the current scene. As shown in Figure 2.28, you should now have three groups named group1, group2, and group3.
Figure 2.28. Scene contents in the Outliner
You can also use Maya's Hypergraph (Windows > Hypergraph) to organize the scene's contents.
Delete group1 and group2, as these are no longer of use.
It's important to stay on top of object naming. Remember that other people may use your work, so try and make it as easy for them as possible.
Next you will need to combine the objects into a single mesh. To do this, simply select all the cubes and go to Polygons > Combine. (For the first time, you will need to switch from the default Animation menu set to the Modeling menu set, or you won't see the Polygons menu.)
As you have built this character, each action you have taken has created an extra node in the construction history. Look in the Channel Box when you have an object selected, and in the Inputs section you can see this history in the form of a long list. This is helpful for going back and editing things, but it also increases the file size and eats up your system's memory. Having a long history could also throw Maya into terminal lock-up if operations such as Polygons > Combine, Edit Polygons > Extract, or Polygons > Smooth are executed on a complex model.
What we can do now to clean up the history is to bake it onto the model by first selecting the character and going to Edit > Delete By Type > History.
Alternatively if you wish to delete the history on every object in the scene simply go to Edit > Delete All by Type > History. This does not require anything to be selected beforehand.
With this version of the Kila model, the amount of detail is really up to you. You could use cylinders, as I will in the upcoming Basic Shape tutorial, to get in a bit more of the character's shape. Or you could just stick to basic boxes. Whatever you choose, make sure you don't spend too long on this version; it is only a placeholder character, after all.
You will find my version of Primitive Kila on the CD in Project Files/02, named Kila_Primitive.mb.