Inside Macintosh: QuickDraw GX Objects /

Chapter 7 - View-Related Objects / View-Related Objects Reference

View Device Functions / Creating and Manipulating View Device Objects

GXCopyToViewDevice

You can use the GXCopyToViewDevice function to create a copy of an existing view device object.

gxViewDevice GXCopyToViewDevice  (gxViewDevice target, 
                                  gxViewDevice source);

target

A reference to the view device to copy the source contents into. If you specify nil for this parameter, the GXCopyToViewDevice function creates a new view device object.

source

A reference to the view device whose contents you want to copy.

function result

A reference to the view device that is a copy of the source view device.

DESCRIPTION

The GXCopyToViewDevice function copies the contents of an existing view device object to another, or it creates a new view device object and copies the contents of an existing view device object to it. The function copies the clip, mapping, bitmap shape (including color space, color profile reference, and color set reference), attributes, and tag list from the source view device. It clones, but does not copy, the tag objects in the tag list.

In copying the bitmap, the GXCopyToViewDevice function does not copy the pixel image itself, just the properties of the bitmap shape. For the color set and color profile properties of the bitmap, and tag objects, GXCopyToViewDevice copies only the references, not the objects themselves.

If you specify nil for the target parameter, the GXCopyToViewDevice function creates a new view port object and copies the properties of the source view device into it.

SPECIAL CONSIDERATIONS

If you attempt to copy to a screen device, this function posts a viewDevice_access_restricted error.

If you specify nil for the target parameter and no error occurs, the GXCopyToViewDevice function creates a view device object; you are responsible
for disposing of that object when you no longer need it.

ERRORS, WARNINGS, AND NOTICES

Errors
out_of_memory
invalid_viewDevice_reference
viewDevice_access_restricted	(debugging version)

SEE ALSO

To create a new view device that has default properties instead of being a copy of an existing view device, use the GXNewViewDevice function, described on page 7-98.

To compare two view device objects for equality, use the GXEqualViewDevice function, described next.

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