About the Printing Messages(IM:XP)

Inside Macintosh: QuickDraw GX Printing Extensions and Drivers /: Chapter 4 - Printing Messages

About the Printing Messages
The printing messages described in this chapter are sent by QuickDraw GX during the process of printing a document. QuickDraw GX provides default implementations of many of these messages that perform the basic task for which the message is intended. This means that you only need to override those messages that apply to the specifics
of your extension or driver. And many of the specifics of a device are defined in the resources that are included in your extension or driver.
For example, since QuickDraw GX provides robust default implementations, you can create a printer driver for a PostScript printer by defining resources and overriding only one message, the GXSetupImageData message. You need to override many messages for some printers and only a few messages for others; however, in most cases the default implementation supplied by QuickDraw GX provides functionality that you want to use. You can override messages to add to or modify that functionality as you need to for your task or device.

Subtopics

Printing Message Terminology