Inside Macintosh: Imaging With QuickDraw /

Appendix A - Picture Opcodes

This appendix describes picture opcodes, which are numbers used by the DrawPicture procedure to determine what object to draw or what mode to change for subsequent drawing. Your application generally should not read or write picture opcodes directly but should instead use QuickDraw routines (described in the chapter "Pictures" in this book) for generating and processing the opcodes. Picture opcodes are listed here for your application's debugging purposes.

The Picture record (described in the chapter "Pictures") begins with a picSize field and a picFrame field, followed by a variable amount of picture definition data in the form of opcodes. The first opcode in any picture must be the version opcode, followed by the version number of the picture.

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Appendix Contents

Version and Header Opcodes

Picture Opcode Data Types

Opcodes in Pictures

A Sample Extended Version 2 Picture

A Sample Version 2 Picture

A Sample Version 1 Picture