Inside Macintosh: QuickDraw GX Objects /

Chapter 6 - Transform Objects / Transform Objects Reference

Functions / Getting and Setting the Mapping

GXSetTransformMapping

You can use the GXSetTransformMapping function to assign a mapping to a transform object.

void GXSetTransformMapping(gxTransform target, 
                           const gxMapping *map);

target

A reference to the transform object you want to assign the mapping to.

map

A pointer to a mapping structure containing the matrix you want to assign as the mapping property of the target transform.

DESCRIPTION

The GXSetTransformMapping function copies information from the mapping structure pointed to by the map parameter into the mapping property of the transform object referenced by the target parameter.

You can specify nil for the map parameter, in which case this function sets the mapping property of the target transform to the identity mapping. (An identity mapping has no transforming effect on shape geometries that it is applied to.)

SPECIAL CONSIDERATIONS

You may provide any values for the elements of the mapping structure pointed to by the map parameter, with one exception: the lower-right element of this matrix (element [2][2]) may not be 0.

ERRORS, WARNINGS, AND NOTICES

Errors
out_of_memory
transform_is_nil
Notices (debugging version)
mapping_unaffected

SEE ALSO

For information about the mapping property of the transform object, see the section "Mapping" beginning on page 6-10. For information about mapping matrices in general, see the mathematics chapter of Inside Macintosh: QuickDraw GX Environment and Utilities.