View Port Objects(IM:XP)

Inside Macintosh: QuickDraw GX Printing /: Chapter 1 - Introduction to Printing With QuickDraw GX / Using Printing-Related Objects With Other QuickDraw GX Objects

View Port Objects
View ports are used to restrict the parts of shapes that are spooled during printing. They also specify how to associate a shape with a view port when reading the shapes from a print file. For example, when you call the GXStartPage function to build your picture shape of the page, you specify a view port list. This view port list controls which shapes are printed. When you call the GXDrawShape function for a shape in order to add the shape to the picture shape, only the part of the shape that shows through a view port in this list is added to the picture shape. When a print file is read, the picture shape is associated with the view ports in the list you specify.

Note
The GXDrawShape function may also cause the shape to be drawn onscreen. If you draw a shape with view ports that are in the onscreen view group but not specified in the view port list when calling the GXStartPage function, the shape is displayed on the screen.
For more information about using view ports with the GXStartPage function, see the chapter "Core Printing Features" in this book. For more information about using view ports when reading print files, see the chapter "Advanced Printing Features" in this book.