But you do that when the opponent is on move. Otherwise nothing would be shown anyway. When we say 'opponent' in these discussion, we mean the opponent of the side that is on move in the displayed position. Not necessarily that of the player who is looking at the page.
In normal usage, a game typically has two players, and each player is the other player's opponent. According to the variable names used in Game Courier, $player is the player whose turn it is to move, and $opponent is the other player. In this specialized usage, only the player's moves are ever shown, and the opponent's moves are never shown. More precisely, only the current player's moves are ever available to be shown, and the attacks the opponent could make are not available to be shown.
When a player moves, $player and $opponent switch values, and that player can then see the moves available to his opponent up until his opponent moves. It would probably be even more useful to show attacks from the opponent when it is not that opponent's turn, but that would take additional programming, and it would be incompatible with another useful feature I just added, which is the ability to capture an opponent's piece in one click if there is only one legal move to its space.
In hindsight, I would like to undo the use of $player and $opponent as variables, because they have hindered my ability to program multi-player games. But at this stage, it would require a lot of reprogramming.
In normal usage, a game typically has two players, and each player is the other player's opponent. According to the variable names used in Game Courier, $player is the player whose turn it is to move, and $opponent is the other player. In this specialized usage, only the player's moves are ever shown, and the opponent's moves are never shown. More precisely, only the current player's moves are ever available to be shown, and the attacks the opponent could make are not available to be shown.
When a player moves, $player and $opponent switch values, and that player can then see the moves available to his opponent up until his opponent moves. It would probably be even more useful to show attacks from the opponent when it is not that opponent's turn, but that would take additional programming, and it would be incompatible with another useful feature I just added, which is the ability to capture an opponent's piece in one click if there is only one legal move to its space.
In hindsight, I would like to undo the use of $player and $opponent as variables, because they have hindered my ability to program multi-player games. But at this stage, it would require a lot of reprogramming.