Inside Macintosh: QuickDraw GX Objects /

Chapter 6 - Transform Objects / Transform Objects Reference

Functions / Getting and Setting the Hit-Test Parameters

GXGetTransformHitTest

You can use the GXGetTransformHitTest function to retrieve the hit-test parameters of a transform object.

gxShapePart GXGetTransformHitTest(gxTransform source, 
                                    Fixed *tolerance);

source

A reference to the transform object whose hit-test parameters you want to examine.

tolerance

A pointer to a Fixed value. On return, the value specifies the hit-test tolerance of the source transform.

function result

The shape-parts mask of the source transform, specifying the shape parts to be tested for.

DESCRIPTION

The GXGetTransformHitTest function returns the contents of the hit-test parameters property of the transform object referenced by the source parameter. The shape-parts mask is returned as the function result and the hit-test tolerance is returned by the tolerance parameter.

Hit-test tolerance is specified in geometry units. You can specify nil for the tolerance parameter, in which case the hit-test tolerance is not returned.

ERRORS, WARNINGS, AND NOTICES

Errors
out_of_memory
transform_is_nil

SEE ALSO

For information about the hit-test parameters property, see "Hit-Test Parameters" beginning on page 6-11. To interpret the values in the shape-parts mask, see Table 6-1 on page 6-12.

To assign hit-test parameters to a transform object, use the GXSetTransformHitTest function, described next.

To retrieve the hit-test parameters of the transform associated with a specified shape, use the GXGetShapeHitTest function, described on page 6-80.