From: Jérôme Benoit <jerome.benoit@piment-noir.org>
Date: Fri, 5 May 2017 18:24:34 +0000 (+0200)
Subject: Merge branch 'master' into playable_shots
X-Git-Url: https://git.piment-noir.org/?p=Project_algorithmic_C.git;a=commitdiff_plain;h=6d7fa659380189a35b8d7cce9f0417b4ed1ce3a5;hp=b5cb4c1247e32f76b64166ac0b776de776374631

Merge branch 'master' into playable_shots

Signed-off-by: Jérôme Benoit <jerome.benoit@piment-noir.org>
---

diff --git a/lib/debug.c b/lib/debug.c
index c7f4dfb..6532079 100644
--- a/lib/debug.c
+++ b/lib/debug.c
@@ -32,3 +32,7 @@ void display_array(int base_y, int base_x, unsigned int pawn_array[board_size][b
         }
     }
 }
+
+/* void dbg_mvprintv(int y, int x, ) {
+
+} */
diff --git a/lib/othello.c b/lib/othello.c
index dd92cfb..5d9970c 100644
--- a/lib/othello.c
+++ b/lib/othello.c
@@ -180,11 +180,11 @@ unsigned int eval_winner(unsigned int nb_white, unsigned int nb_black) {
     }
 }
 
-static unsigned int reverse_one_direction(int y, int x, int direction, unsigned int current_player, unsigned int pawn_array[board_size][board_size]) {
+static unsigned int count_pawn_to_reverse_one_direction(int y, int x, int direction, unsigned int current_player, unsigned int pawn_array[board_size][board_size]) {
     unsigned int nb_pawns_reversed = 0;
     int moving_y = y, moving_x = x;
 
-    /* count for pawns to reverse in the chosen direction */
+    /* count the pawns to reverse in the chosen direction */
     direction_to_coordinates(direction, &moving_y, &moving_x);
     while (true) {
         if (!is_valid_coordinates(moving_y, moving_x) || is_box_type(moving_y, moving_x, pawn_array, empty)) {
@@ -196,9 +196,18 @@ static unsigned int reverse_one_direction(int y, int x, int direction, unsigned
         nb_pawns_reversed++;
         direction_to_coordinates(direction, &moving_y, &moving_x);
     }
+    return nb_pawns_reversed;
+}
+
+/* revert the pawns if needed in one direction */ 
+static unsigned int reverse_one_direction(int y, int x, int direction, unsigned int current_player, unsigned int pawn_array[board_size][board_size], bool dry_run) {
+    unsigned int nb_pawns_reversed = 0;
+    int moving_y = y, moving_x = x;
+
+    nb_pawns_reversed = count_pawn_to_reverse_one_direction(moving_y, moving_x, direction, current_player, pawn_array);
 
     /* now reverse the needed pawns */
-    if (nb_pawns_reversed > 0) {
+    if (nb_pawns_reversed > 0 && !dry_run) {
         moving_y = y, moving_x = x;
         direction_to_coordinates(direction, &moving_y, &moving_x);
         while (!is_box_type(moving_y, moving_x, pawn_array, current_player)) {
@@ -209,6 +218,22 @@ static unsigned int reverse_one_direction(int y, int x, int direction, unsigned
     return nb_pawns_reversed;
 }
 
+/* loop optimized version of valid_shot changing nothing to the pawns 2D array */
+static bool is_legal_shot(int y, int x, unsigned int current_player, unsigned int pawn_array[board_size][board_size]) {
+    unsigned int nb_pawns_reversed = 0;
+    
+    if (!is_valid_coordinates(y, x) || !is_box_type(y, x, pawn_array, empty)) {
+        return false;
+    }
+    
+    for (unsigned int direction = north; direction <= north_west; direction++) {
+        nb_pawns_reversed += reverse_one_direction(y, x, direction, current_player, pawn_array, true);
+        if (nb_pawns_reversed > 0) {
+            return true;
+        }
+    }
+}
+
 /* play the shot if legal and flip or reverse the necessary pawns */
 unsigned int valid_shot(int y, int x, unsigned int current_player, unsigned int pawn_array[board_size][board_size]) {
     unsigned int nb_pawns_reversed = 0;
@@ -218,7 +243,7 @@ unsigned int valid_shot(int y, int x, unsigned int current_player, unsigned int
     }
 
     for (unsigned int direction = north; direction <= north_west; direction++) {
-        nb_pawns_reversed += reverse_one_direction(y, x, direction, current_player, pawn_array);
+        nb_pawns_reversed += reverse_one_direction(y, x, direction, current_player, pawn_array, false);
     }
     
     if (nb_pawns_reversed == 0) {