2009
Table Of Contents
- Contents
- Overview
- Maya Basics
- Polygonal Modeling
- Introduction
- Preparing for the lesson
- Lesson 1: Modeling a polygonal mesh
- Introduction
- Setting modeling preferences
- Using 2D reference images
- Creating a polygon primitive
- Modeling in shaded mode
- Model symmetry
- Selecting components by painting
- Selecting edge loops
- Editing components in the orthographic views
- Editing components in the perspective view
- Drawing a polygon
- Extruding polygon components
- Bridging between edges
- Adding polygons to a mesh
- Splitting polygon faces
- Terminating edge loops
- Deleting construction history
- Mirror copying a mesh
- Working with a smoothed mesh
- Creasing and hardening edges on a mesh
- Beyond the lesson
- NURBS Modeling
- Subdivision Surfaces
- Animation
- Introduction
- Preparing for the lessons
- Lesson 1: Keyframes and the Graph Editor
- Lesson 2: Set Driven Key
- Lesson 3: Path animation
- Lesson 4: Nonlinear animation with Trax
- Introduction
- Open the first scene for the lesson
- Creating clips with Trax
- Changing the position of clips with Trax
- Editing the animation of clips
- Reusing clips within Trax
- Soloing and muting tracks
- Scaling clips within Trax
- Open the second scene for the lesson
- Creating clips from motion capture data
- Extending the length of motion capture data
- Redirecting the motion within a clip
- Beyond the lesson
- Lesson 5: Inverse kinematics
- Introduction
- Open the scene for the lesson
- Understanding hierarchies
- Viewing hierarchies using the Hypergraph
- Creating a skeleton hierarchy
- Parenting a model into a skeleton hierarchy
- Applying IK to a skeleton hierarchy
- Creating a control object for an IK system
- Constraining an IK system
- Limiting the range of motion of an IK system
- Simplifying the display of a hierarchy
- Applying parent constraints on an IK system
- Planning an animation for an IK system
- Animating an IK system
- Beyond the lesson
- Character Setup
- Polygon Texturing
- Rendering
- Introduction
- Preparing for the lessons
- Lesson 1: Rendering a scene
- Introduction
- Open the scene for the lesson
- Creating shading materials for objects
- Refining shading materials for objects
- Maya renderers
- Rendering a single frame using IPR
- Rendering using the Maya software renderer
- Batch rendering a sequence of animation frames
- Viewing a sequence of rendered frames
- Beyond the lesson
- Lesson 2: Shading surfaces
- Lesson 3: Lights, shadows, and cameras
- Lesson 4: Global Illumination
- Lesson 5: Caustics
- Dynamics
- Painting
- Introduction
- Preparing for the lessons
- Lesson 1: Painting in 2D using Paint Effects
- Lesson 2: Painting in 3D using Paint Effects
- Introduction
- Preparing for the lessons
- Brushes and strokes
- Rendering Paint Effects strokes
- Paint Effects on 3D objects
- Creating a surface to paint on
- Painting on objects
- Using turbulence with brush stroke tubes
- Using additional preset brushes
- Mesh brushes
- Converting mesh strokes to polygons
- Modifying a converted polygonal mesh
- Beyond the lesson
- Lesson 3: Painting textures on surfaces
- Expressions
- Scripting in Maya
- Index
4 Go to the start time.
5 With Balloon selected, choose Window > Animation Editors > Expression
Editor.
6 Enter this expression:
if (time < 2)
Balloon.scaleY = time;
This expression is an if statement. The if keyword causes the expression
to make a decision based on a comparison of two or more items. In this
case, the expression compares the value of time to the value 2.
The expression checks whether the value of time is less than two seconds.
If so, it does the assignment Balloon.scaleY = time. If time is not less than
two seconds, the assignment doesn’t occur.
NOTE When you compare the value of time to a number in an expression,
Maya interprets time as seconds rather than milliseconds, minutes, or any
other unit of time. In the example, Maya interprets 2 as two seconds.
Notice how the assignment Balloon.scaleY = time has been formatted so it
appears indented under if (time < 2). Maya ignores all indentation, extra
spaces, and blank lines between statements. We used the indentation to
make the expression easier to read. You could have also written the
expression as follows:
if (time < 2) Balloon.scaleY = time;
This isn’t as easy to read. Consistent, organized spacing is a good habit
to develop. This lesson attempts to show examples of good spacing style
whenever possible.
7 Click Create to compile the expression.
The ball flattens.
The expression executes when you click the Create button. Because the
animation is at frame 0, animation time is 0. Because time is less than 2,
Maya sets Balloon.scaleY equal to the value of time, which equals 0.
A scaleY value of 0 flattens the object in the Y dimension.
8 Playback the animation.
Creating a conditional expression | 575