Chapter 6 - Transform Objects
This chapter describes transform objects and the functions you can use to manipulate them. Read this chapter if you need to clip parts of a shape for drawing, modify the position or dimensions of a shape, modify the view ports to which a shape is drawn, or hit-test a shape.Before reading this chapter, you should be familiar with the information in the chapter "Introduction to QuickDraw GX" in this book. You should also be familiar with shape objects, as discussed in the chapter "Shape Objects" in this book.
For specific information about how transform objects affect bitmap and picture shapes, see Inside Macintosh: QuickDraw GX Graphics. For specific information about how transform objects affect typographic shapes, see Inside Macintosh: QuickDraw GX Typography. For information about the mathematical foundation of transform mappings, see the mathematics chapter of Inside Macintosh: QuickDraw GX Environment and Utilities. For information about view ports, see the chapter "View-Related Objects" in this book.
This chapter introduces QuickDraw GX transform objects and describes their properties. It then shows how to use QuickDraw GX functions to
- create and manipulate transform objects
- manipulate transform object properties, including the clip, view port list, and hit-test parameters
- perform mapping operations to change the translation, rotation, scale, skew, or perspective of transform objects and shape objects
Chapter Contents
- About Transform Objects
- Transform Object Properties
- Clip
- Mapping
- View Port List
- Hit-Test Parameters
- Shape-Parts Mask
- Tolerance
- Setting Up the Parameters
- Default Transform Objects
- Using Transform Objects
- Creating and Manipulating Transform Objects
- Creating and Disposing of Transform Objects
- Copying, Comparing, and Cloning Transform Objects
- Implicit Creation of Transform Objects
- Loading and Unloading Transform Objects
- Manipulating Transform Object Properties
- Manipulating a Transform Object's Owner Count
- Getting and Setting a Transform Object's Tag References
- Resetting Default Transform Properties
- Getting, Setting, and Modifying the Transform Clip
- Moving, Scaling, Rotating, and Skewing Shapes
- Modifying the Transform Mapping
- Modifying Shape Geometry
- Manipulating the View Port List
- Setting Up Hit-Test Parameters
- Transform Objects Reference
- Constants and Data Types
- The Transform Object
- Shape Parts for Hit-Testing
- Functions
- Creating and Manipulating Transform Objects
- Manipulating Transform Object Properties
- Getting and Setting the Clip
- Performing Geometric Operations on Transform Clips
- Getting and Setting the Mapping
- Transforming Shapes by Modifying Transform Mappings
- Transforming Shapes by Modifying Shape Geometries
- Getting and Setting the View Port List
- Getting and Setting the Hit-Test Parameters
- Summary of Transform Objects
- Constants and Data Types
- The Transform Object
- Shape Parts for Hit-Testing
- Functions
- Creating and Manipulating Transform Objects
- Manipulating Transform Object Properties
- Getting and Setting a Transform's Clip
- Performing Geometric Arithmetic on Transform Clips
- Getting and Setting a Transform's Mapping
- Transforming Shapes by Modifying Transform Mappings
- Transforming Shapes by Modifying Shape Geometries
- Getting and Setting a Transform's View Ports
- Getting and Setting a Transform's Hit-Test Parameters