Macro to decide the best search directon on dual-way ring based pointer chains. More...

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Defines
#define	DIR_R 'R'
#define	DIR_L 'L'
#define	DIRECTION(s, d, l) (s>d ? ((((l-s)+d) > (s-d)) ? DIR_L : DIR_R) : (((d-s) > ((l-d)+s)) ? DIR_L : DIR_R))

Detailed Description

Macro to decide the best search directon on dual-way ring based pointer chains.

Define Documentation

#define DIR_L 'L'

"Left" direction, where the ID number decreases (previous element)

Definition at line 36 of file eurephia_directions.h.

#define DIR_R 'R'

"Right" direction, where the ID number increases (next element)

Definition at line 35 of file eurephia_directions.h.

#define DIRECTION	(	s,
		d,
		l
	)		(s>d ? ((((l-s)+d) > (s-d)) ? DIR_L : DIR_R) : (((d-s) > ((l-d)+s)) ? DIR_L : DIR_R))

This macro finds the quickest way to go from one element to another one in a circular dual-way pointer chain, based on a numeric id of the elements.

Parameters:

	s	starting point on the chain
	d	destination point on the chain
	l	number of elements in the chain

Returns:: Returns DIR_R or DIR_L, depending on what will be the shortest distance.

Definition at line 48 of file eurephia_directions.h.