Find the control surface with a given ID
PtSurface_t *PtFindSurface( PtWidget_t *widget, unsigned char surface_id );
This function locates a control surface belonging to a given widget, using the surface's numerical ID, surface_id, as a search key.
A pointer to the structure representing the control surface, or NULL if the specified surface couldn't be found.
|Since control surfaces are maintained internally as an array, it's not uncommon for them to shift around in memory as surfaces are added and removed, thereby possibly invalidating a pointer returned by this function. As such, all surface pointers should be regarded as transient, and you should retrieve an updated copy whenever there's a chance that the widget's surface configuration might have changed.|
Control Surfaces chapter of the Photon Programmer's Guide