Legacy Document

Inside Macintosh: Imaging With QuickDraw /

Chapter 6 - Offscreen Graphics Worlds / Offscreen Graphics Worlds Reference

Data Structures /

GWorldPtr

An offscreen graphics world in Color QuickDraw contains a CGrafPort record--and its handles to associated PixMap and ColorTable records--that describes an offscreen graphics port and contains references to a GDevice record and other state information. The actual data structure for an offscreen graphics world is kept private to allow for future extensions. However, when your application uses the NewGWorld function to create an offscreen world, NewGWorld returns a pointer of type GWorldPtr by which your application refers to the offscreen graphics world. This pointer is defined as follows:

TYPE GWorldPtr = CGrafPtr;

On computers lacking Color QuickDraw, GWorldPtr points to an extension of the GrafPort record.