MAYA Tutorial - Introduction

Maya is the 3-D animation software that provides a number of tools for creating complex characters and animations. Maya's powerful feature set gives you an almost unlimited power to create any kind of animation. The functionality of the Maya software can be extended with the use of MEL (Maya embedded language). MEL can be used to customize the user interface and write scripts and macros. In Maya, you can create objects, lights, cameras and textures. Any object, light, camera, or just any entity can be animated by changing the value of its parameters in time. We can use Maya, to create effects or animations or movies, commercials, architectural animation and forensic animation. Maya can be used to achieve far more complex effects and animation is as compared to other software is on the shelf. This tutorial is aimed at teaching a newbie, the basic concepts and functionality of the Maya software.

MAYA Tutorial - MAYA Interface

Maya user interface looks very complex at first. However, this large number of functions and the scope to add more functions to the user interface provides the real flexibility to the program. Other than the functions common for all the various aspects of a 3d graphics software application, there are set of functions dedicated to a more specific task like modeling, texturing, animation, rendering etc. The default Maya user interface can be divided into the following sections.

• Main Menu Bar
  
  
• Status Line
  
  
• Shelf
  
  
• Tool Box
  
  
• Workspace
  
  
• Panel Menus
  
  
• Time Slider
  
  
• Range Slider
  
  
• Command Line
  
  
• Help Line
  
  
• Channel box
  
  
• Layer editor

Fig 1-1 Maya User Interface

The Menu Bar

There are different menu sets in Maya that correspond to the more specific aspects of the application like Animation, Modeling, Dynamics, Rendering, cloth and Maya Live. The cloth and Maya Live are available with Maya unlimited version. These Menu sets can also be accessed using the hot keys F2, F3, F4 etc.

The menus in the menu sets behave similarly as a normal window menu. Other than the menu sets, there are common menus like File, Edit etc.

Any Menu item that has double lines over it can be dragged of the menu bar to create a min-toolbox so that the commonly used tools can float on the desktop.

You can hide or display different UI elements from the Menu item Display-> UI Elements.

Fig1-2 Menu Bar

The Status Line

The commands available on the status line are mostly use for the purpose of modeling. On the extreme left we have mode selector that helps us to change modes between modeling, animation, rendering or dynamics etc.

A collapser is a clickable switch for hiding a section of the Status Line. Collapsers can be used to hide or display sections of the status line and adjust the number of available functions at an instance.

Fig1-3 Status Line

Selection Mask lets us select the masking preset so that certain types of objects can be ignored while making selections in a 3d panel. The icons to the right of the list box show the masking selections that have been made. The selection mask list box acts as a preset for the buttons in the Select by Type area farther to the right. These buttons correspond to Hierarchy, Object and Component mode. These functions can be used to select entire objects and mask the selection to pick only particular type of objects such as surfaces, lines, cameras etc.

Component Selection mode enables you to adjust subcomponents of an object, such as letting you select a certain portion of an object such as a box or a sphere and deform it. The hierarchy selection mode is used to select only the parent or only the children objects, this comes in handy when setting up object hierarchies.

A selection can be locked by pressing the Lock Selection button. This helps in avoiding accidentally de-selection of an object. Next is Highlight Selection Mode button, a toggle to highlight the selected object in the display.

We use snap tools to ease modeling and modifying objects by making it seem as though an object or part of an object is drawn toward another.

You use the Operations List buttons to view upstream and downstream connections and enable or disable them. Next is Construction History toggle and Maya uses this to record construction. History is not related to the Undo operation. Having Construction History enabled can make files large and slow to load, however, so you might opt to turn it off sometimes.

Next we have the Quick Render, Interactive Photorealistic Renderer(IPR) and Render Globals button. Quick Render and Interactive Photorealistic Renderer is used to render a scene at full quality. IPR rendering is slower, but when finished, it can update the rendering in nearly real time. Next is the Render Globals button, which controls the size of the rendering and many other parameters.

The last we have Numeric Input tool. It can operate in different types of modes. It is used to type in a prefix or common letters and select all the objects you want quickly, rename the currently selected object, and enter an exact value for the current highlighted transform.

Shelf

Shelf contains different tools and commands. The shelf can be customized for one's specific needs. It is used to organize commonly used functions and tools into groups. You can create different shelves for different functions like modeling, animation, texturing etc with the required tools for each function.

Fig1-4 Shelf

Tool Box

Maya Tool Box contains common tools as well as Layout buttons for changing views and layouts. The first one is the select tool. As the name explains itself, while this option is selected, you can use the mouse pointer to click over a particular object to select it. You can also click and drag over a number of objects to select them all together. The lasso tool is also used for selection in a way that you can draw a free hand border around the objects to be selected.

The move, rotate and scale tools are used for transforming objects in Maya. The soft modification tool is used to select the sub-object elements and modify them by moving, rotating or scaling in a way that the neighboring sub-objects also get affected by this deformation with the effect being an inverse of distance from the primary selected sub-objects.

Fig1-5 Toolbox

The last selected tool section shows the last used tool for easy access.

The single perspective view button lets you view the workspace as a single large view from a single perspective. The Four views can be used to view the workspace in four sections with each section containing the three orthographic views top, side and front and a perspective view respectively.

The other combination options below these tools are used to divide the workspace into different section in such a way that one section contains the view of the scene and other contains an animation or rendering editor so that you can edit the attributes and watch the results simultaneously.

Workspace

The Workspace displays by default in a perspective window or panel. The purpose of using workspace is to view your scene. You can display various editors and arrange the workspace panels in different layouts. The workspace can be divided into sections to accommodate the orthographic and perspective views of the scenes as well as the different editors for animation, texturing and rendering etc.

Time Slider and Range Slider

The Two Sliders are for controlling the frames in your animation. The Time Slider includes the playback buttons and the current time indicator. The Range slider includes start and end times and allows animators to focus on a specific part of the animation.

Fig1-6 Time slider and Range slider

Command Line

The command Line lets you enter the MEL (Maya embedded Language) commands to perform various functions. The MEL is a powerful feature of Maya that provides us with a vast flexibility and a scope to exploit the Maya tools beyond the user interface.

The left side is where you can type MEL commands and the right half displays system responses, error messages, and warnings. For a longer series of commands, use the Script Editor. The right side can also show echoes of all commands if you turn on Script> Echo All Commands from the Script Editor.

Fig1-7 Maya Command Line

Help Line

Like several other applications, you can look at the help line for descriptions, instructions, and other useful information. While a tool is selected, the helpline gives out a brief description for "how to" and "what for".

Panel Menus

Every view panel you work in has a common set of menus at the top. The panel menu that appears in a 3d scene, shown here with lighting menu selected. If the panel menus do not appear, you can enable them in Window> Settings/Preferences> Preferences, and then click the Interface entry under the Categories list on the left side of the dialog box.

Under the View menu, you'll see options for Look at Selected, Frame Selected, and Frame All. These options are helpful for finding an item and focusing on it.

Under the Shading menu, the first two entries are Wireframe (hotkey: 4) and Smooth Shade All (hotkey: 5).An important option to note is the NURBS detail mode. When you're working with NURBS, you can display them in three detail levels: low (hotkey: 1), medium (hotkey: 2), or high (hotkey: 3). These hotkeys work only with NURBS.

Fig1-8 Panel Menu

The Lighting menu has an option for using existing lights in the scene (hotkey: 7) with this panel's Shaded mode. Normally, Shaded mode is automatically illuminated (with "default lights") in a crude way that serves to get some light in the scene for viewing or rendering a new model.

Use the Show menu to selectively hide all entities of a certain type. For example, you often use it to hide cameras and lights, just to clean up the view so that you can focus on objects. At the bottom of this menu is an option to hide the grid, which is useful when you want to simplify the view.

Under the Panels menu, use the top three options to select what the panel is seeing in a 3D view.

The next three options let you change the entire layout of the panels. The Panel item displays options for switching the selected panel to some other window, such as a rendered view or the Graph Editor. Next is Layouts, which determines how the view area is split into windows. Below it is Saved Layouts, which is similar to the Quick Layout buttons below the toolbox.

Hotkeys

Hotkeys are also known as keyboard shortcuts. There are several default hotkeys. You can change these hotkeys and assign new ones using the Hotkey editor by

• Selecting Window>Settings/Preferences>Hotkeys.
  
  
• Select the category and command,
  
  
• In the assign new Hotkey area, specify the key combination .You can see a list of which keys are unmapped by clicking List All.

Fig1-9 Hotkey Editor

Viewing hotkey lists

Click List All to view a list of mapped and unmapped keys.

Fig1-10 Hotkeys reference

The Hotbox

Maya's Hotbox is a utility to get quickly to the menus that are available in the menu bar. It pops up when you press and hold spacebar. Once you customize the Hotbox, it provides quick access to the menus you use, hiding menus that are irrelevant to your work. It has five zones with special options. Five zones are North, South, East, West and center.

To see the entire Hotbox, click in the Hotbox Controls section on the right-hand side of the window, and drag your cursor over the Show All option. You might want to come back to this same Hotbox option and disable the Cloth and Live menus if you won't be using them.

Fig1-11 Hotbox

In order to disable the Hotbox, Select window>Settings/Preferences > Hotkeys. The Hotkey Editor window opens. From the editor window select Hotbox in the list of Categories. Select Show Hotbox from the list of commands, Select space from current Hotkeys, and then click on the Remove button. This turns off the hotkey functionality. Click the Save button and then the close button.

MAYA Tutorial - Transforms in MAYA

"Transform" of an object means three functions: position, rotation, and scale. Each function has three components—for X, Y, and Z. So transform contains 9 variables in total 3 defining each function. When you create a scene entity, its transform appears in the Channel Box. Here you will learn how to scale, rotate, and move your objects. Whenever you give a command in Maya to create an object, it is created using default transform which defines the position to be in the center of the scene at 0,0,0 coordinates, or origin.

In order to customize the object transform, you need to move, rotate, and scale the object to place it in the position you want. You can Move, scale, and rotate the primitive object into its final position either by direct manipulation or by entering numeric values through an editor.

You can also Duplicate the primitive objects to create multiple copies of the original or create different variations from your original primitive object.

When you create a new primitive in Maya, it becomes the selected object. In the Channel Box, you can access the object's creation parameters, the ones used most often to modify a new shape.

The ToolBox

In order to manipulate an object's transform, the basic tools required from the toolbox are select tool, lasso serves a similar purpose, move tool for changing the position of the object, rotate tool for changing the orientation of the object and the scale tool for changing the scale of the object.

Fig2-1 The basic transform tools

Selecting Objects

There are many ways to select objects in Maya.

• You can select object individually.
• You can select all objects in the scene.
• You can select objects of a specified type.
• You can select objects of a specified name.
• You can select all objects in a set.
• You can select all objects in a display layer.

Inverting a Selection

Use Invert Selection to select all objects in the scene that are not selected. For example if you select two of five objects in a scene and then select Edit>Invert Selection, the other three objects are selected instead. This only works on objects not components.

To select all displayed objects

Select Edit > Select All

To deselect all objects

Click anywhere in the view.

Using Transforms

When you are in the Move (hotkey: w), Rotate (hotkey: e), or Scale (hotkey: r) mode, you have several options for transforming the object . Generally, if you click and drag on the surface of a selected object, or on the center point for the manipulator handles, you can freely move or rotate the object. In Scale mode, the object scales uniformly. You can also click and drag on any of the handles to have the action constrained to that axis.

The Move Tool

Click the Move Tool icon in the Tool Box and then select the object you want to move. Maya displays a manipulator with four handles-one to move along each axis and one to move anywhere with in the planes.

Fig2-2 The move tool

Click one of the handles, as indicated above. The selected handle changes color when active .The default color is yellow. If you double-click on the Tool Box icons for move, rotate, and scale, you get options for the tools (none appear for scale, but at least an empty dialog box appears). A useful option in this dialog box is snap spacing.

The Rotate Tool

It use the Rotate Tool to rotate objects about any or all three axes. Click the Rotate Tool icon in the Tool Box. Select the object you want to rotate. Maya displays a rotate manipulator consisting of four rings plus a virtual sphere enclosed by the rings or handles. The colors correspond to XYZ axes.

Fig2-3 The rotate tool

Click one of the handles, as indicated above. The selected handle changes color when active .The default color is yellow. Use the X, Y, Z rings to perform constrained rotations. Use the outer ring to rotate relative to the view.

When you rotate a component, Maya rotates it about a temporary pivot which is initially set to the center of the component's bounding box. In the rotate options, you can find the option to set snaps, which is helpful when you want to rotate objects in discrete increments. A good setting might be 15 degrees to make it easy to rotate objects to precise 30-, 45-, 60-, and 90-degree positions. Note that this snapping happens only when you use a manipulator's axis handle.

The Scale Tool

Use the Scale Tool to change the size of the objects by scaling proportionally in all three dimensions. You can also scale non- proportionally in one dimension at a time.

Click the Scale Tool icon in the Tool Box and select the object you want to scale. Maya displays a scale manipulator consisting of four handles. The color corresponds to XYZ axes.

Fig2-4 The scale tool

Soft Modification Tool

This lets you push and pull geometry .By default, the amount of deformation is greatest at the center of the push/pull, and gradually falls off further away from the centre. However, you can control the falloff of the deformation to create various types of effects.

You can use this tool on NURBS surfaces, polygonal surfaces, subdivision surfaces, curves, particles or any object with components.

Show Manipulator Tool

This Tool lets you edit the construction history of an operation or the attributes of an object itself. This tool lets you access the input node of an object. A manipulator is a good way to access the history of a surface created with the construction history. Several manipulators can be active at one time.

Undoing and Redoing

Undo reverse the last action you performed on a selected object. This action transform an object to its original position.

Select Edit>Undo

Select Edit>Redo to perform the last action you reversed.

Duplicating Objects

Sometimes, you need to copy an object many times to create a complex object. Maya's object duplicator is under Edit > Duplicate on the menu. The default is to duplicate an object in place; you can do this with the hotkey Ctrl +d. The new duplicate appears by default exactly over the original object, so you normally follow a duplication with a transform.

Sometime, you want to create more than one duplicate. Use the Edit > Duplicate Option box to modify how duplicates are made.

Instancing

Another way to copy object is instancing. Maya redisplays the geometry being instanced. Since instances are not actual copies of the original geometry.

There are certain demerits of using instancing

• Instances share the same shader as the original geometry and can not be assigned as independent shaders.
  
  
• Instanced lights have no effect.
  
  
• When you create an instance of an already instanced node, Maya does not create a new level.
  
  
• Functions like extrude and insert can not be used on instanced items.

Snapping

The Snap options let you control an object or component's position by attaching it to a grid, point, curve or view plane. As you draw, rotate, resize or drag the objects ,it snap to the grid, point, curve or view plane.

Fig2-5 Snapping options

Snap to grids

This option snaps a vertex or pivot point to a grid corner. If you select snap to grids before you create a curve, its vertices snap to the grid corners.

Snap to curves

This option snaps a vertex or pivot point to a curve or curve on surface.

Snap to points

This option snaps a vertex or pivot point to a point.

Snap to view planes

This option snaps a vertex or pivot point to a view plane.

Snapping hotkeys

x for grid snap

c for curve snap

v for point snap

How to use the grid Snap HotKey?

Select the object you want to snap and click the Move tool icon. Press and hold down the c key while click-dragging on the curve you want to snap with the middle mouse button.

Similarly you can use rest of the keys

Outliner

You can use outliner to examine the structure and components of the scene. It also displays shape nodes, connections and attributes. With the outliner you can make an object the child of a parent object. It selects and renames an object. Last but not least it reorder nodes.

To open the Outliner in the window

Select Window > Outliner

Fig2-6 The outliner

Grouping

Sometimes, you have groups of objects in your scene that are related to each other without being connected as a single entity. Any collection of objects can be selected and made into a group by choosing Edit>Group on the menu. Note that the objects are not tied up into this bundle; you can still select them independently. There's simply a new object that stands for the collection.

Parenting and Grouping

Parents and children in hierarchies work as follows: Where the parent goes, the child must follow, but the child is otherwise free to roam. The child objects can still be animated independently, however, without affecting the parent .With groups, the group node can be animated and all the members of the group follow the group node, but the group's members can still animate independently of the group. When you group several objects, Maya creates the group transform node, which can't be rendered.

You can directly assign hierarchical relationships to objects by selecting the child object(s), Shift-clicking to select the parent, and then choosing Edit >Parent (hotkey: p). Any transform applied to the parent is then reflected in the child. You can also break this bond by using Edit>Unparent (hotkey: Shift+P). This works only when the child object or objects are selected.

Channel Box

This is used to modify an object's attribute values. You can change multiple attribute values of multiple objects. It takes up less much less space in the window. With this you can control construction history. It appears in the Maya Window only it you choose to display it. The information displayed in the Channel Box varies, depending on what kind of object or component you have selected. If you haven't selected an object, the Channel Box region is blank.

In order to display the channel box

Turn on Display> UI Elements > Channel Box/Layer Editor.

MAYA Tutorial - Nurbs Curves and Surfaces

Maya offers a powerful modeling system known as NURBS—Non-Uniform Rational B-Splines. NURBS modeling is not simply putting objects together. Unlike fixed polygons , NURBS create 3D objects from curves and surfaces. Therefore, NURBS can be modeled in a variety of ways.

NURBS modeling is considered a better alternative to SUBd modeling as it gives you more precise control. They have their own rules and limitations for how you can build, attach, and cut them, but in general, they are quite flexible. The faceted, low-resolution look that often occurs when creating curved surfaces with polygons is easily handled in NURBS models, which can display curved surfaces as virtually any number of polygons.

To make it a little simpler, however, NURBS are simply a variation of splines, which are used to define a curve. Curves are the basis for the underlying mathematical structure of what makes up a NURBS surface. Nurbs modeling has capability for creating:

• organic ,flowing surfaces such as animals, human bodies and fruits.
  
  
• Industrial surfaces such as automobiles, clocks and toasters.
  
  
• Smooth surfaces adjustable over broad areas with few control points.

Nurbs Primitives

Nurbs primitives are common geometric objects such as spheres, cubes and cylinders. They are often used as the foundation for other shapes.

Sphere

Select Create > Nurbs primitives >Sphere. After you set the options ,click the Create button.

Pivot

By default, the pivot is set to Object and the primitive is created at the origin. If you set Pivot to User defined, you can enter values in the Pivot point X, Y and Z boxes to position the pivots.

Axis

Select X, Y or Z to specify a preset axis direction of the object. Select Active View to create the object perpendicular to the current orthographic view. The Active view option has no effect when the current modeling view is a camera or perspective view.

Sweep Angles

These options let you create a partial sphere by specifying a degree of rotation. Degree values can range from 0 to 360 degree.

Radius

Sets the width and depth of the primitive.

Surface Degree

A linear surface has a faceted appearance : a cubic surface is rounded.

Sections

Set the number of surface curves created on the sphere in one direction. These curves are also called isoparms, show the outline of the surface shape.

Fig 3-1 Sections

Spans

Set the number of surface curves created on the sphere in the direction that crosses the section direction.

Fig 3-2 Spans

Cube

A cube has six sides, each of them is selectable. You can select a side of the cube in the view or click its heading in the outliner.

Width, Length and Height sets the cube dimensions.

Cylinder

You can create a cylinder with or without end caps. End caps is a unique feature to the creation of the cylinder. You can create caps for either, both or no ends of the cylinder.

Cone

You can create a cone with or without a cap on its base.

Plane

A plane is flat surface made up of specified number of patches .

Torus

A torus is a 3d ring.

Circle

A circle is a curve not a surface. Its features are similar to the sphere.

Curves

The foundation of a Nurbs surface is a curve. Surfaces are web of interconnected curves. The curves help you create and modify surfaces. Proficiency at drawing and editing curves is an important part of Nurbs modeling.

You can not render curves. With Nurbs curves ,you can position points on a curve or surface exactly where you want them and reshape the curve or surface by moving just a few control points that lie on or near the curve. Examples of NURBS primitives are spheres, cubes, cylinders, cones and planes.

A major advantage of modeling with NURBS in Maya is that you can convert any NURBS object to Subdivision Surfaces (also called "SubDs") or polygons at any time.

Using NURBS can have its drawbacks, however. When modeling a character that needs to be animated, you might notice seams, or even visible gaps, between NURBS surfaces .As a result of the way NURBS are constructed, you rarely come up with an object composed of a single surface, and the surfaces must meet together exactly to avoid these problems.

Elements of a Curve

The elements of a curve follow:

A curve point is an arbitrary point on the curve. It can have the same position as a CV or edit point.

CVs are control vertices ,These points often lie away from the curve.

Edit points are also called knots. You can move these points to reposition a specific point on the curve. You can't move the edit points of a surface.

The start of a curve is the first point of the curve created when you draw the curve.The end of the curve is the last point of the curve you create. You need to know which points are the start and end points for certain modeling operations.

The curve direction is displayed as a small letter u.

A hull is a network of straight lines that connects CVs. Hulls are mainly visual aids to see where interconnected CVs exist.

A span is the point of a curve between the two edit points. If you add extra edit points to a curve enhance your control of its shape, you increase the number of spans. you don't select and manipulate a curve span directly.

Fig 3-3 Elements of curve

Tools for Creating Curves

There are three tools for creating curves

1. Create > CV Curve Tool
   
   
2. Create > EP Curve Tool
   
   
3. Create > Pencil Curve Tool

CV Curve Tool

This Tool creates the curve's CV exactly where you click them. It creates edit points based on where you create the CVs. When it turns white, you have created enough CVs to complete the curve. You must create at least four CVs when you use the default option settings.

EP Curve Tool

The EP Curve Tool creates the curve's edit points exactly where you click them. It creates CVs in positions based on where you create the edit points. EP stands for edit points. You must place at least two edit points to create the curve.

Pencil Curve Tool

The Pencil Tool lets you draw a curve by dragging the mouse or by using a digitizing pen and tablet. When you create a curve using the Pencil Curve Tool, you can not delete curve segments by pressing the Backspace key.

Maya creates a trail of edit points and sometimes several curves where you drag the mouse or pen. The CVs created with this tool might seem to pose efficiency and control problems, you can simplify the curves with Edit Curves > Rebuild Curve.

Attaching curves

Use Edit Curves > Attach Curves to create a single curve from two curves.

Attach Method

Connect joins the curves with minimal curvature smoothing at the joint point.

Blends smooths the curvature at the joint point based on the blend Bias value.

Detaching Curves

Use Edit Curves > Detach Curves to break a curve into two curves or to open a closed curve.

Construction Plane

Use Create > Construction Plane to create a plane as a construction aid. You can not rotate a construction plane, make it a live surface, then draw a curve on it. You can not render or animate a construction plane.

Select create > Construction Plane to open the option window.

Fig 3-4 Construction plane options

Pole Axis

Sets the orientation of the construction plane. The default is an XY plane.

Fig 3-5 Orientation of the construction plane

Size

Sets the size of the plane in grid units.

Extending curves

Use Edit Curves> Extend >Extend curve to extend a curve beyond its original creation length. To extend a revolve surface ,you can extend the curve used by the revolve operation.

Select Edit curves > Extend > Extend Curve and set the desired options.

Click the Extend button.

By default the curve is extended 2 unit at its end.

Fig 3-6 Extending curves

Reversing the curve direction

Select Edit Curves > Reverse Curve Direction.

Rebuilding curves

Use Edit Curves > Rebuild curve to rebuild a Nurbs curve or curve on surface to smooth it or lessen its complexity.

Lofting Curves and Surfaces

Lofting is used to construct a surface that passes through a series of profile curves. The curves can be curves -on -surface, surface isoparms or trimmed edges.

With the help of Loft feature, you can create intermediate areas between any two surfaces created with boundary curves. Before you begin ,you need at least two profiles curves or surface isoparms.

Pick the first curve you want to loft, then shift-click to pick subsequent curves.

Select Surfaces >Loft

You can add new curves to an existing lofted surfaces created with construction history.

Birail Tools

Birail Tools that create a surface by sweeping one or more profile curve along two rail curves. Birail 1 sweeps one profile curve, Birail 2 sweeps two, Birail 3+ sweeps three or more.

Before using Birail Tool ,you must check all workspace to make sure the profile curve (s) intersected the rail curves. Profile and rail curves can be isoparms, curves -on-surface,trim boundaries or boundary curves of an existing surfaces.

Select Surfaces > Birail >Birail n Tool.

Beveling Surfaces

Bevel is used to create an extruded surface with a beveled edge from any curve, including text curves and trim edges. You can bevel surfaces for instance, to create a ledge on a building or the rolled edge on an upholstered chair.

Click the curve you want to bevel and select Surfaces > Bevel.

Bevel width

This value specifies the initial width of the bevel as viewed from the front of the curve or isoparm.

Bevel Depth

This value sets the initial depth of the bevel part of the surface. The combination of bevel width and depth sets the bevel angle.

Extrude Height

This value specifies the height of extruded portion of the surface, not including the bevel surface area.

Bevel Corners

This options specify how corners in the original construction curves are handled in the beveled surface.

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MAYA Tutorial - Polygonal Modeling

Polygonal modeling is typically used for hard-edged surfaces that don't bend or in situations where low polygon counts are important, such as modeling for games. With Maya 5, you can easily convert between polygons, SubDs, and NURBS patches. This allows you to begin the model in one format and then convert to another, if necessary, or to use the advantages of editing or rendering a model in another format.

Polygonal Primitives

There are several ways to use primitives to build objects quickly and easily. Use primitives as a starting point, then uses a combination of polygon creation and editing operations to complete a task. The most basic object type is primitive. Primitives are pure shapes that can be used as the basis of creating more complex models. There are six polygonal primitives objects---sphere, Cone, Cylinder, Cube, Plane and Torus.

Fig4-1 Polygon primitives

To create a primitive with the default option settings, select create > Polygon Primitives and choose the primitive you want to create from the menu. You can always edit the primitive from the channel Box or its Attribute Editor.

Fig 4_2 Attribute Editor

Section Radius option

The section Radius option value specifies the size of the sections .Change this value to increase or decrease the radius of sections to see the result.

Subdivision Axis

For spheres, cylinders, cones and toruses , this option defines the number of subdivisions there are around the axis defined by the Axis option. This option is also called Subdivisions Axis .Increase or decrease this value to add or take away faces around the axis defined by the Axis option.

Subdivision Height

This option defines the number of subdivisions there are along the axis defined by the Axis option. Height is equivalent to the Y directions by default.Increase or decrease this value to add or take away faces in the Axis direction.

Fig4-3 Subdivision height

Creating and Editing Text

The Poly text type creates text as Polygons .When this text type is selected, a planar trim curve is created between the curves and tessellate nodes. By default, Maya creates text as Nurbs geometry.

To create polygonal text

• Select Create > Text to open the Text Curves option window and set the Type option to poly.
  
  
• Type the text you want to write in the text box.
  
  
• Change the default font settings if required.
  
  
• Change the option settings.
  
  
• Click the create button to create the text.

Polygonal Text Settings

When you create polygonal text, Maya provides option that you can set to display and create your text for subsequent polygonal-type editing.

Triangles

Three sided polygons are created. This is the default.

Tessellation Methods

Standard fit

This is the default tessellation method. It is adaptive tessellation, meaning that following option is used to determine when to stop the tessellation. The tessellation stops at the fractional tolerance value you set. If there is an edge shorter than the Minimal Edge Length, the tessellation stops on that edge. If the surface is flat enough with in the edge, the tessellation stops here.

General

Set the tessellation method to General to display the following options. Unless Use chord height or use chord height ratio is turned on, a uniform tessellation is performed. Each span is split into a number of polygons depending on the number U and V values you set.

Count

Set the tessellation method to Count to display the Following slider. Count slider is used to determine how many polygons the surface can be tessellated into.

Control points

This tessellation method converts the Nurbs model to polygons while matching the CVs of the original Nurbs surface. There are no other options for this operation.

Extruding

You can pull faces and edges out from polygonal objects using the Extrude Face and Extrude Edge commands.

Extruding Faces

You can extrude faces either interactively or directly through the option window. Select Edit Polygons > Extrude Face ,set whatever option you need and click the Extrude Face button.

• If you want to extrude all the faces of an object, marquee-select the whole object to highlight the faces.
• If you want to extrude certain areas of an object, shift-or Ctrl-click to select those face only.
• If you want to extrude ,duplicate or extract multiple faces together, turn on polygons > Tool options >Keep Faces Together.

you are not happy with results, select Undo from the Edit menu, change the Extrusions settings in the channel Box or Attribute Editor and press Enter.

Extruding Edges

You can extrude edges either interactively or directly through the option window. If you prefer to set the options first and then extrude the edges, Select Edit Polygons > Extrude Face.

Duplicating Faces

You can duplicate and transform faces interactively or directly through the option window. Select the faces of the object you want to duplicate. Press the right mouse button and select Face or press F11.

• If you want to duplicate all the faces of an object, marquee-select the whole object to highlight the faces.
  
• If you want to duplicate certain areas of an object, click to select those face only.

You can also Duplicate Faces through Edit Polygons > Duplicate Face.

Extracting Faces

While Extracting ,Maya disconnects the selected Faces from the original shape, by duplicating the appropriate edges and vertices. The extracted faces become their own shell with in the object. This is the another way to make holes in the object while retaining their original faces.

Seperating the extracted faces creates distinct polygons out of the faces and the original object.

To extract Faces

• Select the face of the object you want to extract. Press the right mouse button and select Face from the marking menu or press F11,then shift or Ctrl-Click to select the faces.
• Select edit Polygons > Extract. The selected Faces are extracted.

Fig4-4 Extracting faces

Smoothing Polygons

There are three ways to smooth polygons.

• Using Polygons > smooth.
• Using Polygons >Average vertices.
• Using the smooth operation of the sculpt polygons Tool to average the values of painted vertices to produce a smoother surface.

Polygon Selection

With Edit Polygons > Selection menu, you can constrain the selection of components to a specified area of a polygonal model and perform operations on those components in that specified area only without disturbing the rest of the model.

Select Edit Polygon > Selection >Grow Selection Region to increase the number of components you initially selected.

Selecting Boundaries

You use Edit Polygons >Selection >Select Selection Boundary to define the boundary of the current selection region. It is a quick way to select the boundaries of whatever is currently selected.

Selection a band of edges

Use Edit Polygons > Selection > Select Contiguous Edges to select a contiguous band of edges around model. With this you can select one edge, choose select Contiguous Edges, and it will select the rest of the edges in the center automatically.

Max 2d Angle ,Max 3d Angle

These settings determine how far the selection continues based on the angles between edges. The 2d angle refers to angle made by the surface topology, regardless of the surface's shape. The 3d angle refers to angles made by the surface's shape, as measured in world or local space.

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MAYA Tutorial - Texturing and Shading

Materials are a critical part of creating attractive images and animation in a 3D program. Materials interact with lights, so lighting drives some material choices; for example, if your overall lighting is bright, you might need to make your scene materials somewhat more matte and light absorbing so that they don't blow out when hit by bright lights.

What do we mean by "materials"? It's a catch-all term to describe all aspects of what a surface looks like. At first glance, beginners usually notice the surface color—red, wood brown, metallic silver. To an artist, however, there are many other factors: An object isn't just metallic silver, for example—it's a mirrored smooth finish that relies on the reflected surroundings for its appearance. In addition to factors of color, shine, and reflection, Maya also considers transparency, incandescence, translucency, refraction, bumpiness, and many other user-controlled parameters. Attention to these details gives your rendered results more subtlety and complexity.

Hypershade

Maya's Hypershade is one of the first and most important areas you should take the time to explore. It provides a quick and easy way to create,edit, and connect rendering nodes, such as textures, materials, lights, rendering utilities and special effects.

Hypershade uses a free-form approach to material design. Swatches connect to one another to create effects; for example, a brick image might connect to the Bump attribute of a material to create bumps in the pattern of bricks. Hypershade also doubles as a kind of browser so that you can view and select existing scene lights, cameras, materials, and other elements.

To open Hypershade, choose Window > Rendering Editors > Hypershade (hotkey: Alt+h).

Fig 5-1 Hypershade

Hypershade displays each node as an icon, sometimes called a swatch, that represents the characteristics of the node. When you edit a node's attributes or assign textures or special effects, that swatch updates in hypershade.

Create Bar

At the left is the Create Bar, which displays all the material types you can create for a selected category. Simply click on a type to create that item in the Work Area. To select a category, click the down arrow on the Create Bar; the options are Materials, Textures, Lights, Utilities, and All Nodes.

Tab Panels

The top tab shows existing materials, and the bottom tab is used to create and edit materials. After you become familiar with Hypershade, you can customize the tabs to your liking and even add Work Area tabs to simultaneously edit several materials.

Top Tab

This area displays all the elements that are already part of the current scene file in these tabs: Materials, Textures, Utilities, Lights, Cameras, and Projects. In this tab, you can duplicate, edit, select objects assigned to shading groups, link lights, import and export materials, and a number of other functions

Bottom Tab

This area is usually used as the Work Area—the assembly point for new materials.

Basic Material Types

Lambert

Lambert is a flat material type that yields a smooth look without specular highlights. It calculates without taking into account surface or reflectivity, which gives a matte, chalk-like appearance. Lambert material is ideal for surfaces that don't have highlights: pottery, chalk, matte paint, and so forth. By default, any newly created object is assigned the Lambert shader.

Phong

The Phong material takes into account specular reflectivity to create highlights across an object surface. The algorithm can be customized for surfaces such as plastic, porcelain, and glazed ceramic.

PhongE

PhongE is a faster rendering version of Phong that yields somewhat softer highlights than Phong.

Blinn

The Blinn material calculates highlights on surfaces similarly to Phong; however, Blinn can achieve a more accurate representation of the soft tinted highlights you see on metallic surfaces. Because Blinn is a versatile material type and doesn't cause flickering with bump maps.

Anisotropic

The Anisotropic material type stretches highlights and rotates them based on the viewer's position. Anisotropic materials are ideal for materials such as hair, feathers, brushed metal, and satin.

Ramp Shader

The Ramp Shader material consists of built-in ramp graphs to offer more advanced control and simplify the shader network.

Ocean Shader

The Ocean Shader material has several items in the shader's attributes that control how the material behaves over time, and it has graphs to add detail to the base shader. Attributes include Wave Speed, Wave Height, Wave Turbulence, and Wave Peaking.

Layered Shader

The Layered Shader lets you combine several materials to create a more complex material.

Shading Map

The Shading Map material is primarily designed to let you get a "cel" look in 3D, like typical animated cartoons.

Surface Shader

The Surface Shader is used when you want to control a material's color, transparency, and glow with something else in Maya.

Use Background

The Use Background shader cuts a "hole" in the image's alpha channel where objects with the material appear. This material is useful for combining separately rendered images in a compositing program to create the final results.

Material Settings

To edit material settings, double-click on any material in Hypershade's top or bottom tabs. Usually, you create a Blinn material in the Work Area of the bottom tab panel, and then double-click it to edit it in the Attribute Editor.

Fig 5_2 Material settings in the attribute editor

Notice the material name at the top of the Attribute Editor, which Maya sets to blinn1 for a default starting name. Maya increments the number if you create more Blinn materials. Next is the Common Material Attributes section, followed by the Specular Shading section. These two sections, displayed by default, are used the most in material editing.

Color

The default material color.

Transparency

If the transparency value is 0(black),the surface is totally opaque; if the transparency value is 1(white),the surface is totally transparent. If you change transparency from the default black ,the background of the material's hypershade swatch becomes a checked pattern .This is not a visual aid and is not rendered.

Ambient Color

Uses Black by default. As the ambient color becomes lighter, it affect's the material's color by lightening it and blending the two colors.

Incandescence

The color and the brightness of light that a material appears to be emitting. The default color value is 0.

Bump Mapping

Makes the surface appear more rough or bumpy by altering surface normals according to the intensity of the pixels in the bump map texture. A bump map does not actually alter the surface.

Diffuse

Gives the material ability to reflect light in all directions. The diffuse value acts like a scaling factor applied to the color setting-the higher the diffuse value, the closer the actual surface is to the color setting.

Translucence

Gives the material the ability to transmit and diffuse light. Light falling on a translucent surface is first absorbed beneath the surface and then diffused in all directions. The slider range is 0 to 1.

Surface Material Attributes

Specular color

The color of shiny highlights on the surface. A black specular color produces no surface highlights. The default color value is 0.5.

Reflectivity

Gives the surface the ability to reflect its surroundings or the reflected color. The default color value is 0.5.

Reflected color

Represents the color of light reflected from the material. This can be used to tint a reflection.

Surface Material

Fig 5-3 Surface Materials

Anisotropic

Represents surfaces with grooves, such as cd or feathers etc. Anisotropic material (such as Phong or Blinn)reflects specular light identically in all directions.If you spin an isotropic sphere, its specular highlight remains still.

Roughness

Determines the overall roughness of the surface. The range is 0.01 to 1.0.The default is 0.7.Smaller values correspond to smoother surfaces and the specular highlights are more concentrated.

Fresnel Index

A fresnel is a flat lens consisting of a number of concentric rings that reduces spherical abnormalities. The Fresnel index for water is 1.33.Value range from 1.0 to 20.0.

Anisotropic Reflectivity

If on, Maya automatically calculates Reflectivity as a fraction of roughness. Reflectivity is on by default.

Blinn Attributes

Color The base color of the surface.

Transparency Adjusts the surface opacity. You can use colors to create a tinted glass effect.

Ambient Color Adds to and blends with the color value.

Incandescence A simulation of emitted light. At low values, it tints and self-illuminates the material, and at high values, it overtakes the material's color and becomes self-illuminated.

Diffuse By default, it's set to 0.8, which dulls down the color value you've set.

Translucence A special effect in which light is absorbed and scattered as it passes through an object, useful for simulating materials such as frosted glass.

Translucence Focus Controls how light scatters from the surface.

Eccentricity The width of the highlight, simulating how polished or rough the surface appears.

Specular Roll Off The brightness/intensity of the highlight.

Specular Color The color of the highlight; usually set to white or a gray value.

Reflectivity The strength of reflections on the object. Reflections can be raytraced or use texture maps.

Reflected Color For Blinn, the color swatch and slider have no effect. However, when a texture map is applied, it appears to be reflected by the material.

Lambert

Represents matte surface(such as chalk,matte paint,unpolished surfaces) with no specular highlights. The initial shading group uses a lambert material.

Layered Shader Attributes

Represents a single surface material composed of several different surface materials layered on top of one another.

Transparency

By default the material is semi-transparent.

Compositing Flag

Composites the layers using a layered shader or layered texture mode.

Hardware color

Helps you distinguish the objects assigned to a layered shader in the views.

Phong Attributes

Represents glassy or glossy surfaces with a hard specular highlight.

Cosine power

This feature is available to the phong material. Controls the size of shiny highlights on the surface. The default value is 20.

Phong E Attributes

A simpler version of the phong material. The specular highlights on the Phong E surfaces are softer than those on Phong Surfaces and Phong E surfaces render faster than Phong surfaces.

Roughness

Controls the specularity focus.

Highlight Size

Controls the amount of specular highlight.

Whiteness

Controls the specular highlight color. The default value is white. You can also map a texture to this value.

Shading Map Attributes

Represents a color map you apply to surfaces after they are rendered.The shading map material is useful for creating non-photorealistic effects(cartoon shading)or to highlight threshold values in a rendered image.

Shading Map Color

Defines the color of the material. The default is gray.

Shader

You can map any material to the shading Map material.

Surfaces Shader Attributes

A wrapper node, meaning you can connect any keyable attribute to this shading group and then connect the shading group to an object.

Out color

The color of the material .The default is black.

Out Transparency

The transparency of the material. The default is black.

Out Glow Color

The glow color of the material. The default is black, without glow.

Use Background

You use it to set the object's Matte channel to 1 or 0, or create a matte for shadows and reflections on the surface. This material applies the same color as the objects in the background image to stand -in-surfaces.

Attributes

Adjust the Use Background material's to the light ,shadows, reflections and the geometry placement in the scene.

Texture Mapping

Normally, a texture refers to applying a 2D image around a 3D surface, rather like wallpapering a curvy surface. Because a 2D image can be stretched, wrapped, and projected onto a surface in many different ways.

Mapping Coordinates

Mapping coordinates, also known as UV coordinates. For NURBS, parametric mapping is inherent to the surface and this is typically what's used. Parametric mapping is the 0 to 1 coordinate system that NURBS uses to map textures across its surfaces. It makes sure that the textures stay mapped to the surface like a decal, even if the geometry is deformed.

For polygon surfaces, mapping is normally applied by projecting 2D maps across the 3D surface in one of several ways: planar, cylindrical, spherical, and a special method called automatic mapping.

Fig 5-4 Mapping projection

Procedural Maps

In addition to applying an image or movie to a surface, Maya has other texture types called procedural textures. Many patterns, such as bricks, tiles, and gradients, are so repetitive that they can easily be represented by an equation. By using special forms of seemingly random values, many natural effects can be simulated mathematically: Marble, leather, water, granite, and many other complex and random textures are included with Maya as procedurals.

Maya's procedural textures come in two varieties: 2D and 3D. You can think of the 2D procedurals as a calculated form of a bitmap.When 3D procedurals are applied, however, they exist throughout 3D space, and object surfaces define where you see the texture. It's like carving the object from a block of the material.Procedural textures have several benefits. Because they are formula based, their parameters can be adjusted to instantly synthesize all kinds of different effects.

2D Procedurals

Maya's 2D procedurals can be divided into two categories: regular patterns and noise patterns. The regular patterns include Grid, Checker, Bulge, Cloth, and Ramp. With these patterns, you can create tiles, bricks, and many other man-made repeating effects. Noise patterns include Fractal, Mountain, Noise, and Water. These psuedorandom textures are excellent for creating the complex "dirty" surfaces common in nature.

3D Procedurals

All the 3D procedurals but snow are random types. Some, such as wood and marble, clearly imitate nature. However, all are excellent for synthesizing random effects.

Assigning material to surfaces

The following lists a few quick ways to assign a material to a surface.

• In the view,select the surface to which you want to assign the material.
  
  
• From Hypershade, MMB-drag the material swatch over the selected surfaces.

or

• In the view ,shift-select the object to which you want to assign the material and in hypershade,click the material swatch.
  
  
• While the cursor is over the material swatch in hypershade,RMB -click-drag to select assign material to selection from the pop-up menu.

or

• MMB-drag and drop a Hypershade swatch onto an object in the IPR Render view.

To apply a material to several surfaces from with Hypershade

• Select the surfaces in a view.
• In Hypershade,RMB-click over the material swatch and select Assign material to selection from the pop-up menu.

To apply a material to a group of faces on a polygonal surface

• Select the surface.
  
  
• Press the RMB while over the surface,select face from the marking menu,then choose the select by component type icon.
  
  
• Select the face you want to map.
  
  
• While the faces are highlighted in the view, in hypershade,LMB-shift-click over the material swatch you want and press theRMB and select Assign material to selection from the pop-up menu.

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