Another function pair required for serialisation; these ones save

and restore anything vitally important in the game_ui. Most of the
game_ui is expected to be stuff about cursor positions and currently
active mouse drags, so it absolutely _doesn't_ want to be preserved
over a serialisation; but one or two things would be disorienting or
outright wrong to reset, such as the Net origin position and the
Mines death counter.

[originally from svn r6026]

cube.c

@@ -1004,6 +1004,15 @@ static void free_ui(game_ui *ui)
 {
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -1714,6 +1723,8 @@ const struct game thegame = {
     FALSE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

fifteen.c

@@ -436,6 +436,15 @@ static void free_ui(game_ui *ui)
 {
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -882,6 +891,8 @@ const struct game thegame = {
     TRUE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

flip.c

@@ -871,6 +871,15 @@ static void free_ui(game_ui *ui)
 {
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -1229,6 +1238,8 @@ const struct game thegame = {
     FALSE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

guess.c

@@ -404,6 +404,15 @@ static void free_ui(game_ui *ui)
     sfree(ui);
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -1260,6 +1269,8 @@ const struct game thegame = {
     FALSE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

mines.c

@@ -2357,6 +2357,21 @@ static void free_ui(game_ui *ui)
     sfree(ui);
 }
 
+char *encode_ui(game_ui *ui)
+{
+    char buf[80];
+    /*
+     * The deaths counter needs preserving across a serialisation.
+     */
+    sprintf(buf, "D%d", ui->deaths);
+    return dupstr(buf);
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+    sscanf(encoding, "D%d", &ui->deaths);
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -3039,6 +3054,8 @@ const struct game thegame = {
     TRUE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

net.c

@@ -1846,6 +1846,23 @@ static void free_ui(game_ui *ui)
     sfree(ui);
 }
 
+char *encode_ui(game_ui *ui)
+{
+    char buf[120];
+    /*
+     * We preserve the origin and centre-point coordinates over a
+     * serialise.
+     */
+    sprintf(buf, "O%d,%d;C%d,%d", ui->org_x, ui->org_y, ui->cx, ui->cy);
+    return dupstr(buf);
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+    sscanf(encoding, "O%d,%d;C%d,%d",
+	   &ui->org_x, &ui->org_y, &ui->cx, &ui->cy);
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -2739,6 +2756,8 @@ const struct game thegame = {
     FALSE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

netslide.c

@@ -1005,6 +1005,15 @@ static void free_ui(game_ui *ui)
     sfree(ui);
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 /* ----------------------------------------------------------------------
  * Process a move.
  */
@@ -1822,6 +1831,8 @@ const struct game thegame = {
     FALSE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

nullgame.c

@@ -142,6 +142,15 @@ static void free_ui(game_ui *ui)
 {
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -255,6 +264,8 @@ const struct game thegame = {
     FALSE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

pattern.c

@@ -773,6 +773,15 @@ static void free_ui(game_ui *ui)
     sfree(ui);
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -1194,6 +1203,8 @@ const struct game thegame = {
     FALSE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

puzzles.h

@@ -275,6 +275,8 @@ struct game {
     char *(*text_format)(game_state *state);
     game_ui *(*new_ui)(game_state *state);
     void (*free_ui)(game_ui *ui);
+    char *(*encode_ui)(game_ui *ui);
+    void (*decode_ui)(game_ui *ui, char *encoding);
     void (*changed_state)(game_ui *ui, game_state *oldstate,
                           game_state *newstate);
     char *(*interpret_move)(game_state *state, game_ui *ui, game_drawstate *ds,

rect.c

@@ -2170,6 +2170,15 @@ static void free_ui(game_ui *ui)
     sfree(ui);
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void coord_round(float x, float y, int *xr, int *yr)
 {
     float xs, ys, xv, yv, dx, dy, dist;
@@ -2799,6 +2808,8 @@ const struct game thegame = {
     TRUE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

samegame.c

@@ -411,6 +411,15 @@ static void free_ui(game_ui *ui)
     sfree(ui);
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void sel_clear(game_ui *ui, game_state *state)
 {
     int i;
@@ -999,6 +1008,8 @@ const struct game thegame = {
     TRUE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

sixteen.c

@@ -564,6 +564,15 @@ static void free_ui(game_ui *ui)
 {
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -1060,6 +1069,8 @@ const struct game thegame = {
     TRUE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

solo.c

@@ -1931,6 +1931,15 @@ static void free_ui(game_ui *ui)
     sfree(ui);
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -2420,6 +2429,8 @@ const struct game thegame = {
     TRUE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,

twiddle.c

@@ -608,6 +608,15 @@ static void free_ui(game_ui *ui)
 {
 }
 
+char *encode_ui(game_ui *ui)
+{
+    return NULL;
+}
+
+void decode_ui(game_ui *ui, char *encoding)
+{
+}
+
 static void game_changed_state(game_ui *ui, game_state *oldstate,
                                game_state *newstate)
 {
@@ -1224,6 +1233,8 @@ const struct game thegame = {
     TRUE, game_text_format,
     new_ui,
     free_ui,
+    encode_ui,
+    decode_ui,
     game_changed_state,
     interpret_move,
     execute_move,