Legacy Document

Inside Macintosh: QuickDraw GX Environment and Utilities /

Chapter 1 - QuickDraw GX and the Macintosh Environment / QuickDraw GX and the Macintosh Environment Reference

Macintosh Interface Functions / Installing a View Port Filter

GXGetViewPortFilter

You can use the GXGetViewPortFilter function to return the view device of a specified graphics device.

gxUserViewPortFilter GXGetViewPortFilter(gxViewPort portOrder,
                                          long *refCon);

portOrder

A reference to the view port whose currently installed view port filter you need.

refCon

A pointer to a long value. On return, the value is the reference constant that was passed to the GXSetViewPortFilter function when the filter function was installed.

function result

A pointer to the view port filter function that is installed in the specified view port.

DESCRIPTION

The GXGetViewPortFilter function returns a pointer to the view port filter that is currently installed in the specified view port. The function also returns, in the refCon parameter, the reference constant that was passed to GXSetViewPortFilter when the filter function was installed.

ERRORS, WARNINGS, AND NOTICES

Errors

out_of_memory

invalid_viewPort_reference

SEE ALSO

The GXSetViewPortFilter function is described in the previous section.

For a description of the prototype of the view port filter function, see page 1-40.