Legacy Document

Inside Macintosh: QuickDraw GX Environment and Utilities /

Chapter 8 - QuickDraw GX Mathematics / QuickDraw GX Mathematics Reference

Mapping Functions / Manipulating and Applying Mappings

InvertMapping

You can use the InvertMapping function to create an inverted copy of a mapping.

gxMapping *InvertMapping(gxMapping *target, 
                         const gxMapping *source);

target

A pointer to a mapping structure. On return, contains the inverse of the mapping specified in the source parameter.

source

A pointer to the mapping to be inverted.

function result

A pointer to the inverted mapping, which is also the target mapping.

DESCRIPTION

The InvertMapping function creates a copy of the source mapping, inverts it, and returns the inverted mapping in the target parameter. If both the source and target parameters point to the same gxMapping structure, that mapping will be replaced by its inverse. If the mapping is not invertible, the function returns nil and the target is not changed.

ERRORS, WARNINGS, AND NOTICES

Errors

mapping_is_nil