Inside Macintosh: 3D Graphics Programming With QuickDraw 3D /

Chapter 15 - Pick Objects / Pick Objects Reference

Data Structures

Pick Data Structure

You use a pick data structure to specify information when creating a pick object for subsequent picking. A pick data structure is defined by the TQ3PickData data type.

typedef struct TQ3PickData {
   TQ3PickSort                sort;
   TQ3PickDetail              mask;
   unsigned long              numHitsToReturn;
} TQ3PickData;

Field Description

sort

A hit list sorting value that determines the kind of sorting, if any, that is to be done on the hit list.

mask

A hit information mask that determines the type of information to be returned for the items in a hit list.

numHitsToReturn

The maximum number of hits to return. QuickDraw 3D discards any hits that would exceed this limit, but only after all possible hits have been found and placed into the sort order determined by the sort field. You can specify the constant kQ3ReturnAllHits to request that all hits be returned.