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Retrieve information about a region
int PhRegionQuery( PhRid_t rid,
                   PhRegion_t *region,
                   PhRect_t *rect,
                   void *data,
                   unsigned data_len );
This function returns information about the region identified by rid. Upon completion, region and rect contain a description of the region.
If the region has data attached to it, then the data, up to data_len bytes, is copied into data. This data may consist of smaller blocks of data of different types, each preceded by a PhRegionDataHdr_t structure. To find a specific type of data in the region's data, call PhRegionDataFindType().
The following example gets information about the device region:
PhRegion_t region; PhRect_t rect;
if( !PhRegionQuery( Ph_DEV_RID, ®ion,
                    &rect, NULL, 0 ) ) {
  printf( "Sensitive to: %.8x Opaque to: %.8x\n", 
    region.events_sense, region.events_opaque );
  printf( "Located at: {(%d,%d),(%d,%d)}\n", 
     region.origin.x + rect.ul.x,
     region.origin.y + rect.ul.y, 
     region.origin.x + rect.lr.x,
     region.origin.y + rect.lr.y );
}
Photon
| Safety: | |
|---|---|
| Interrupt handler | No | 
| Signal handler | No | 
| Thread | No | 
PhRegion_t, PhRegionChange(), PhRegionOpen()
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