Inside Macintosh: Apple Game Sprockets Guide /

Chapter 2 - DrawSprocket / DrawSprocket Reference

DrawSprocket Functions / Handling a Mouse

DSpFindContextFromPoint

You can use the DSpFindContextFromPoint function to find out which context corresponds to a point given in global coordinates.

OSStatus DSpFindContextFromPoint (
Point inGlobalPoint,
DSpContextReference *outContext);

inGlobalPoint

A point in global coordinates.

outContext

On exit, a reference to a context that contains that point.

function result

A result code.

DESCRIPTION

If the user moves the mouse, the game needs to know which context it's in so that the global coordinates can be properly translated into local coordinates for the context. The function takes, in the inGlobalPoint parameter, the global coordinates of a point and returns, in the outContext parameter, a reference to the context that point is in.

CALLING RESTRICTIONS

Do not call this function during an interrupt.