Unnecessary, computer takes a while. My suggestion is to check for continuous indestructible effective blockades that range from one side of the board to the other. This solves the problems.
For everything else we have we have the simple material check.
Well even on an open board what is or isn't sufficient material to force mate is a bit more complicated than in standard chess as there can be fairy pieces, different royals, players without royals, and even different rules.
For instance you could have a RvsK endgame, on an open board, which isn't counted as insufficient material, but without the help of a king a rook can't even stalemate a king, and the king can't trap the rook, meaning that capture of the rook can't be forced.
Or you could have a player with a royal queen, and what is needed to checkmate a royal queen, on an open board depends on the size of the board.
Or you could have something like a KGGvsK, on an open board, which is not counted as insufficient material, but, on an open board, 2 grasshoppers can't checkmate a king.
Or you could have a King and pawn vs King endgame, on an open board, but have the pawn either not allowed to promote, or only allowed to promote to a knight or bishop, in which case the king and pawn isn't enough to checkmate the king.
oh though you were talking about non-fairy piece variants, but really your suggestion is not way to go
Based on this I was thinking that an alternative to having the computer check for sufficient material would be to have the computer first check whether one player can checkmate on the next move, and then, if there is no mate on the next move, use brute force to check whether there are sequences of moves that can result in 2 move forced checkmate combinations. If after looking through a large search tree the computer cannot find any 2 move forced checkmate combinations then, the computer would declare the game over and give the same number of points to the remaining players as it would for insufficient material. If the computer finds sequences of moves that would result in 2 move forced checkmate combinations then it would allow the game to continue.
Wouldn't this mean it would essentially be a 3 move rule instead of a 50 move rule? Or am I missing something?
I saw in this discussion on how to get computers to recognize dead draw positions
someone propose having the computer use brute force to search for helpmates with the idea that if the position is truly a dead draw then no matter how many move sequence possibilities a computer searches, it will not be able to find any resulting in checkmate, but if the position is not a dead draw then if the computer checks enough random sequences of moves then it should be almost guaranteed to find a helpmate sequence.
I notice that the material counts, in which the game is over on this site seem to be ones, in which in regular chess there can be no 2 move checkmate combinations. For instance KNvsKB cannot have any 2 move forced mate combinations in regular chess, and so the game ends if it reaches such a position, but KNNvsKB can have 2 move forced mate combinations as when the king can't move but is not in check, the bishop can still move.
Based on this I was thinking that an alternative to having the computer check for sufficient material would be to have the computer first check whether one player can checkmate on the next move, and then, if there is no mate on the next move, use brute force to check whether there are sequences of moves that can result in 2 move forced checkmate combinations. If after looking through a large search tree the computer cannot find any 2 move forced checkmate combinations then, the computer would declare the game over and give the same number of points to the remaining players as it would for insufficient material. If the computer finds sequences of moves that would result in 2 move forced checkmate combinations then it would allow the game to continue.
I think this could be a good way to get the computer to detect positions, in which no player can force a mate in more than 1 move without having to individually program each situation into the computer.