So I will change the definition to that it should not go back to the previously visited square on the path.
That, I think, would be the ideal. :)
A good algorithm would be to tabulate first which squares you can reach in one step, and then from all of those take another step to tabulate those you can reach in two steps, eliminating duplicats at every stage.
That can be great, though sometimes where a piece can move from a square depends on where it came from. With a Rose, for example, any square that can be reached in 2 or 3 steps has two ways of approaching (unless blocked), and each of those two ways has a different allowed exit -- four if the Rose is allowed to go full circle. Some complex bent sliders, the Combine being the most common, also have overlapping moves. The algorithm would be perfect for pieces like the Ubi-Ubi or Shogi area movers, and probably would also improve regular radial sliders and oblique riders (especially those with cannon, grasshop, or juggernaut moves), but there should be some way to allow for "this way in, that way out" (like ignoring the elimination of duplicates after a turn modifier is encountered).
That, I think, would be the ideal. :)
That can be great, though sometimes where a piece can move from a square depends on where it came from. With a Rose, for example, any square that can be reached in 2 or 3 steps has two ways of approaching (unless blocked), and each of those two ways has a different allowed exit -- four if the Rose is allowed to go full circle. Some complex bent sliders, the Combine being the most common, also have overlapping moves. The algorithm would be perfect for pieces like the Ubi-Ubi or Shogi area movers, and probably would also improve regular radial sliders and oblique riders (especially those with cannon, grasshop, or juggernaut moves), but there should be some way to allow for "this way in, that way out" (like ignoring the elimination of duplicates after a turn modifier is encountered).