Introduce a new game backend function (there seem to have been a lot

of these recently) whose job is to update a game_ui to be consistent
with a new game_state. This is called by midend.c in every situation
where the current game_state changes _other_ than as a result of
make_move (Undo, Redo, Restart, Solve).

The introduction of this function allows a game_ui to contain
information about selections or highlights within a game_state which
simply wouldn't make sense when transferred to another game_state.
In particular, I've used it to fix a subtle bug in Solo whereby,
although you couldn't right-click to pencil-mode highlight a filled
square, you could _get_ a pencil-mode highlight in a filled square
if you used Undo and Redo. (Undo to before the square was filled,
right-click to highlight it, then Redo. Alternatively, left-click
and clear the square, right-click to highlight it, then Undo.)

[originally from svn r5912]

1 files changed, 6 insertions, 0 deletions

diff --git a/netslide.c b/netslide.c
index 0ab3e34..e6751fe 100644
--- a/netslide.c
+++ b/netslide.c
@@ -1045,6 +1045,11 @@ static void slide_col(game_state *state, int dir, int col)
     slide_col_int(state->width, state->height, state->tiles, dir, col);
 }
 
+static void game_changed_state(game_ui *ui, game_state *oldstate,
+                               game_state *newstate)
+{
+}
+
 static game_state *make_move(game_state *state, game_ui *ui,
                              game_drawstate *ds, int x, int y, int button)
 {
@@ -1749,6 +1754,7 @@ const struct game thegame = {
     FALSE, game_text_format,
     new_ui,
     free_ui,
+    game_changed_state,
     make_move,
     game_size,
     game_colours,