Important: The information in this document is obsolete and should not be used for new development.
Chapter 5 - Graphics Devices
This chapter describes how Color QuickDraw manages video devices so that your application can draw to a window's graphics port without regard to the capabilities of the screen--even if the window spans more than one screen.Read this chapter to learn how Color QuickDraw communicates with a video
device--such as a plug-in video card or a built-in video interface--by automatically creating and managing a record of data typeGDevice
. Your application generally never needs to createGDevice
records. However, your application may find it useful to examineGDevice
records to determine the capabilities of the user's screens. When zooming a window, for example, your application can useGDevice
records to determine which screen contains the largest area of a window, and then determine the ideal window size for that screen. You may also wish to use theDeviceLoop
procedure, described in this chapter, if you want to optimize your application's drawing for screens with different capabilities.This chapter describes the
GDevice
record and the routines that Color QuickDraw uses to create and manage such records. This chapter also describes routines that your application might find helpful for determining screen characteristics. For many applications, QuickDraw provides a device-independent interface; as described in other chapters of this book, your application can draw images in a graphics port for a window, and Color QuickDraw automatically manages the path to the screen--even if the user has multiple screens. However, if your application needs more control over how it draws images on screens of various sizes and with different capabilities, your application can use the routines described in this chapter.
Chapter Contents
- About Graphics Devices
- Using Graphics Devices
- Optimizing Your Images for Different Graphics Devices
- Zooming Windows on Multiscreen Systems
- Setting a Device's Pixel Depth
- Exceptional Cases When Working With Color Devices
- Graphics Devices Reference
- Data Structures
- Routines for Graphics Devices
- Creating, Setting, and Disposing of GDevice Records
- Getting the Available Graphics Devices
- Determining the Characteristics of a Video Device
- Changing the Pixel Depth for a Video Device
- Application-Defined Routine
- Resource
- The Screen Resource
- Summary of Graphics Devices
- Pascal Summary
- Constants
- Data Types
- Routines for Graphics Devices
- Application-Defined Routine
- C Summary
- Constants
- Data Types
- Functions for Graphics Devices
- Application-Defined Function
- Assembly-Language Summary
- Data Structure
- Global Variables