[gnugo-devel] handicap code restructuring

[Gunnar Farneback]

This patch breaks the function placehand() out of genmove.c and moves
it into a new file handicap.c. There is no change in functionality.

The reason for the change is to prepare for some new code to generate
free placement handicaps. This will be much enough to warrant a
separate file for the handicap code.

- new file engine/handicap.c
- placehand() moved from genmove.c to handicap.c

/Gunnar

Index: engine/Makefile.am
===================================================================
RCS file: /cvsroot/gnugo/gnugo/engine/Makefile.am,v
retrieving revision 1.10
diff -u -r1.10 Makefile.am
--- engine/Makefile.am  22 Mar 2002 08:18:32 -0000      1.10
+++ engine/Makefile.am  17 Aug 2002 21:33:49 -0000
@@ -26,6 +26,7 @@
       fuseki.c \
       genmove.c \
       globals.c \
+      handicap.c \
       hash.c \
       influence.c \
       interface.c \
Index: engine/Makefile.in
===================================================================
RCS file: /cvsroot/gnugo/gnugo/engine/Makefile.in,v
retrieving revision 1.33
diff -u -r1.33 Makefile.in
--- engine/Makefile.in  25 Mar 2002 04:47:27 -0000      1.33
+++ engine/Makefile.in  17 Aug 2002 21:33:50 -0000
@@ -108,6 +108,7 @@
       fuseki.c \
       genmove.c \
       globals.c \
+      handicap.c \
       hash.c \
       influence.c \
       interface.c \
@@ -155,7 +156,7 @@
 am_libengine_a_OBJECTS = aftermath.$(OBJEXT) board.$(OBJEXT) \
        cache.$(OBJEXT) clock.$(OBJEXT) combination.$(OBJEXT) \
        dragon.$(OBJEXT) filllib.$(OBJEXT) fuseki.$(OBJEXT) \
-       genmove.$(OBJEXT) globals.$(OBJEXT) hash.$(OBJEXT) \
+       genmove.$(OBJEXT) globals.$(OBJEXT) handicap.$(OBJEXT) hash.$(OBJEXT) \
        influence.$(OBJEXT) interface.$(OBJEXT) life.$(OBJEXT) \
        matchpat.$(OBJEXT) move_reasons.$(OBJEXT) movelist.$(OBJEXT) \
        optics.$(OBJEXT) owl.$(OBJEXT) printutils.$(OBJEXT) \
@@ -176,7 +177,7 @@
 @AMDEP_TRUE@   $(DEPDIR)/combination.Po $(DEPDIR)/dragon.Po \
 @AMDEP_TRUE@   $(DEPDIR)/filllib.Po $(DEPDIR)/fuseki.Po \
 @AMDEP_TRUE@   $(DEPDIR)/genmove.Po $(DEPDIR)/globals.Po \
address@hidden@ $(DEPDIR)/hash.Po $(DEPDIR)/influence.Po \
address@hidden@ $(DEPDIR)/handicap.Po $(DEPDIR)/hash.Po $(DEPDIR)/influence.Po \
 @AMDEP_TRUE@   $(DEPDIR)/interface.Po $(DEPDIR)/life.Po \
 @AMDEP_TRUE@   $(DEPDIR)/matchpat.Po $(DEPDIR)/move_reasons.Po \
 @AMDEP_TRUE@   $(DEPDIR)/movelist.Po $(DEPDIR)/optics.Po \
@@ -239,6 +240,7 @@
 @AMDEP_TRUE@@am__include@ @address@hidden(DEPDIR)/address@hidden@
 @AMDEP_TRUE@@am__include@ @address@hidden(DEPDIR)/address@hidden@
 @AMDEP_TRUE@@am__include@ @address@hidden(DEPDIR)/address@hidden@
address@hidden@@am__include@ @address@hidden(DEPDIR)/address@hidden@
 @AMDEP_TRUE@@am__include@ @address@hidden(DEPDIR)/address@hidden@
 @AMDEP_TRUE@@am__include@ @address@hidden(DEPDIR)/address@hidden@
 @AMDEP_TRUE@@am__include@ @address@hidden(DEPDIR)/address@hidden@
Index: engine/genmove.c
===================================================================
RCS file: /cvsroot/gnugo/gnugo/engine/genmove.c,v
retrieving revision 1.45
diff -u -r1.45 genmove.c
--- engine/genmove.c    6 Aug 2002 19:04:11 -0000       1.45
+++ engine/genmove.c    17 Aug 2002 21:33:51 -0000
@@ -614,176 +614,6 @@
 }
   
 
-/* ================================================================ */
-/*       Set up fixed placement handicap stones for black side      */
-/* ================================================================ */
-
-
-/* Handicap stones are set up according to the following diagrams:
- *  
- * 2 stones:                    3 stones:           
- *
- *   A B C D E F G H J           A B C D E F G H J  
- * 9 . . . . . . . . . 9       9 . . . . . . . . . 9
- * 8 . . . . . . . . . 8       8 . . . . . . . . . 8
- * 7 . . + . . . X . . 7       7 . . X . . . X . . 7
- * 6 . . . . . . . . . 6       6 . . . . . . . . . 6
- * 5 . . . . + . . . . 5       5 . . . . + . . . . 5
- * 4 . . . . . . . . . 4       4 . . . . . . . . . 4
- * 3 . . X . . . + . . 3       3 . . X . . . + . . 3
- * 2 . . . . . . . . . 2       2 . . . . . . . . . 2
- * 1 . . . . . . . . . 1       1 . . . . . . . . . 1
- *   A B C D E F G H J           A B C D E F G H J  
- *   
- * 4 stones:                    5 stones:           
- *                                                  
- *   A B C D E F G H J           A B C D E F G H J  
- * 9 . . . . . . . . . 9       9 . . . . . . . . . 9
- * 8 . . . . . . . . . 8       8 . . . . . . . . . 8
- * 7 . . X . . . X . . 7       7 . . X . . . X . . 7
- * 6 . . . . . . . . . 6       6 . . . . . . . . . 6
- * 5 . . . . + . . . . 5       5 . . . . X . . . . 5
- * 4 . . . . . . . . . 4       4 . . . . . . . . . 4
- * 3 . . X . . . X . . 3       3 . . X . . . X . . 3
- * 2 . . . . . . . . . 2       2 . . . . . . . . . 2
- * 1 . . . . . . . . . 1       1 . . . . . . . . . 1
- *   A B C D E F G H J           A B C D E F G H J  
- *  
- * 6 stones:                    7 stones:           
- *                                                  
- *   A B C D E F G H J           A B C D E F G H J  
- * 9 . . . . . . . . . 9       9 . . . . . . . . . 9
- * 8 . . . . . . . . . 8       8 . . . . . . . . . 8
- * 7 . . X . . . X . . 7       7 . . X . . . X . . 7
- * 6 . . . . . . . . . 6       6 . . . . . . . . . 6
- * 5 . . X . + . X . . 5       5 . . X . X . X . . 5
- * 4 . . . . . . . . . 4       4 . . . . . . . . . 4
- * 3 . . X . . . X . . 3       3 . . X . . . X . . 3
- * 2 . . . . . . . . . 2       2 . . . . . . . . . 2
- * 1 . . . . . . . . . 1       1 . . . . . . . . . 1
- *   A B C D E F G H J           A B C D E F G H J  
- *  
- * 8 stones:                    9 stones:           
- *                                                  
- *   A B C D E F G H J           A B C D E F G H J  
- * 9 . . . . . . . . . 9       9 . . . . . . . . . 9
- * 8 . . . . . . . . . 8       8 . . . . . . . . . 8
- * 7 . . X . X . X . . 7       7 . . X . X . X . . 7
- * 6 . . . . . . . . . 6       6 . . . . . . . . . 6
- * 5 . . X . + . X . . 5       5 . . X . X . X . . 5
- * 4 . . . . . . . . . 4       4 . . . . . . . . . 4
- * 3 . . X . X . X . . 3       3 . . X . X . X . . 3
- * 2 . . . . . . . . . 2       2 . . . . . . . . . 2
- * 1 . . . . . . . . . 1       1 . . . . . . . . . 1
- *   A B C D E F G H J           A B C D E F G H J  
- *  
- * For odd-sized boards larger than 9x9, the same pattern is followed,
- * except that the edge stones are moved to the fourth line for 13x13
- * boards and larger.
- *
- * For even-sized boards at least 8x8, only the four first diagrams
- * are used, because there is no way to place the center stones
- * symmetrically. As for odd-sized boards, the edge stones are moved
- * to the fourth line for boards larger than 11x11.
- *
- * At most four stones are placed on 7x7 boards too (this size may or
- * may not be supported by the rest of the engine). No handicap stones
- * are ever placed on smaller boards.
- *
- * Notice that this function only deals with fixed handicap placement.
- * Larger handicaps can be added by free placement if the used
- * interface supports it.
- */
-
-
-/* This table contains the (coded) positions of the stones.
- *  2 maps to 2 or 3, depending on board size
- *  0 maps to center
- * -ve numbers map to  board_size - number
- *
- * The stones are placed in this order, *except* if there are
- * 5 or 7 stones, in which case center ({0, 0}) is placed, and
- * then as for 4 or 6.
- */
-
-static const int places[][2] = {
-
-  {2, -2}, {-2, 2}, {2, 2}, {-2, -2}, /* first 4 are easy */
-                                      /* for 5, {0,0} is explicitly placed */
-  
-  {0, 2}, {0, -2},                    /* for 6 these two are placed */
-                                      /* for 7, {0,0} is explicitly placed */
-  
-  {2, 0}, {-2, 0},                    /* for 8, these two are placed */
-
-  {0, 0},                             /* finally tengen for 9 */
-};
-
-
-/*
- * Sets up handicap stones, returning the number of placed handicap stones.
- */
-
-int
-placehand(int handicap)
-{
-  int x;
-  int maxhand;
-  int three = board_size > 11 ? 3 : 2;
-  int mid = board_size/2;
-  int retval = handicap;
-
-  /* A handicap of 1 just means that B plays first, no komi.
-   * Black is not told where to play the first stone so no handicap
-   * is set. 
-   */
-  if (handicap < 2)
-    return 0;
-  if ((board_size % 2 == 1) && (board_size >= 9))
-    maxhand = 9;
-  else if (board_size >= 7)
-    maxhand = 4;
-  else
-    maxhand = 0;
-
-  /* It's up to the caller of this function to notice if the handicap
-   * was too large for fixed placement and act upon that.
-   */
-  if (handicap > maxhand) {
-    handicap = maxhand;
-    retval = maxhand;
-  }
-
-  /* special cases: 5 and 7 */
-  if (handicap == 5 || handicap == 7) {
-    add_stone(POS(mid, mid), BLACK);
-    handicap--;
-  }
-
-  for (x = 0; x < handicap; ++x) {
-    int i = places[x][0];
-    int j = places[x][1];
-
-    /* translate the encoded values to board co-ordinates */
-    if (i == 2)  i = three;    /* 2 or 3 */
-    if (i == -2) i = -three;
-
-    if (j == 2)  j = three;
-    if (j == -2) j = -three;
-
-    if (i == 0) i = mid;
-    if (j == 0) j = mid;
-
-    if (i < 0) i += board_size-1;
-    if (j < 0) j += board_size-1;
-
-    add_stone(POS(i, j), BLACK);
-  }
-
-  return retval;
-}
-
-
 /* revise_semeai(color) changes the status of any DEAD dragon of
  * OPPOSITE_COLOR(color) which occurs in a semeai to UNKNOWN.
  * It returns true if such a dragon is found.
@@ -852,8 +682,6 @@
   
   return 1;
 }
-
-
 
 
 /*
Index: engine/handicap.c
===================================================================
RCS file: engine/handicap.c
diff -N engine/handicap.c
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ engine/handicap.c   17 Aug 2002 21:33:52 -0000
@@ -0,0 +1,202 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
+ * This is GNU GO, a Go program. Contact address@hidden, or see       *
+ * http://www.gnu.org/software/gnugo/ for more information.          *
+ *                                                                   *
+ * Copyright 1999, 2000, 2001, 2002 by the Free Software Foundation. *
+ *                                                                   *
+ * This program is free software; you can redistribute it and/or     *
+ * modify it under the terms of the GNU General Public License as    *
+ * published by the Free Software Foundation - version 2             *
+ *                                                                   *
+ * This program is distributed in the hope that it will be useful,   *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of    *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the     *
+ * GNU General Public License in file COPYING for more details.      *
+ *                                                                   *
+ * You should have received a copy of the GNU General Public         *
+ * License along with this program; if not, write to the Free        *
+ * Software Foundation, Inc., 59 Temple Place - Suite 330,           *
+ * Boston, MA 02111, USA.                                            *
+\* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+#include "gnugo.h"
+
+#include "liberty.h"
+#include "random.h"
+
+/* ================================================================ */
+/*       Set up fixed placement handicap stones for black side      */
+/* ================================================================ */
+
+
+/* Handicap stones are set up according to the following diagrams:
+ *  
+ * 2 stones:                    3 stones:           
+ *
+ *   A B C D E F G H J           A B C D E F G H J  
+ * 9 . . . . . . . . . 9       9 . . . . . . . . . 9
+ * 8 . . . . . . . . . 8       8 . . . . . . . . . 8
+ * 7 . . + . . . X . . 7       7 . . X . . . X . . 7
+ * 6 . . . . . . . . . 6       6 . . . . . . . . . 6
+ * 5 . . . . + . . . . 5       5 . . . . + . . . . 5
+ * 4 . . . . . . . . . 4       4 . . . . . . . . . 4
+ * 3 . . X . . . + . . 3       3 . . X . . . + . . 3
+ * 2 . . . . . . . . . 2       2 . . . . . . . . . 2
+ * 1 . . . . . . . . . 1       1 . . . . . . . . . 1
+ *   A B C D E F G H J           A B C D E F G H J  
+ *   
+ * 4 stones:                    5 stones:           
+ *                                                  
+ *   A B C D E F G H J           A B C D E F G H J  
+ * 9 . . . . . . . . . 9       9 . . . . . . . . . 9
+ * 8 . . . . . . . . . 8       8 . . . . . . . . . 8
+ * 7 . . X . . . X . . 7       7 . . X . . . X . . 7
+ * 6 . . . . . . . . . 6       6 . . . . . . . . . 6
+ * 5 . . . . + . . . . 5       5 . . . . X . . . . 5
+ * 4 . . . . . . . . . 4       4 . . . . . . . . . 4
+ * 3 . . X . . . X . . 3       3 . . X . . . X . . 3
+ * 2 . . . . . . . . . 2       2 . . . . . . . . . 2
+ * 1 . . . . . . . . . 1       1 . . . . . . . . . 1
+ *   A B C D E F G H J           A B C D E F G H J  
+ *  
+ * 6 stones:                    7 stones:           
+ *                                                  
+ *   A B C D E F G H J           A B C D E F G H J  
+ * 9 . . . . . . . . . 9       9 . . . . . . . . . 9
+ * 8 . . . . . . . . . 8       8 . . . . . . . . . 8
+ * 7 . . X . . . X . . 7       7 . . X . . . X . . 7
+ * 6 . . . . . . . . . 6       6 . . . . . . . . . 6
+ * 5 . . X . + . X . . 5       5 . . X . X . X . . 5
+ * 4 . . . . . . . . . 4       4 . . . . . . . . . 4
+ * 3 . . X . . . X . . 3       3 . . X . . . X . . 3
+ * 2 . . . . . . . . . 2       2 . . . . . . . . . 2
+ * 1 . . . . . . . . . 1       1 . . . . . . . . . 1
+ *   A B C D E F G H J           A B C D E F G H J  
+ *  
+ * 8 stones:                    9 stones:           
+ *                                                  
+ *   A B C D E F G H J           A B C D E F G H J  
+ * 9 . . . . . . . . . 9       9 . . . . . . . . . 9
+ * 8 . . . . . . . . . 8       8 . . . . . . . . . 8
+ * 7 . . X . X . X . . 7       7 . . X . X . X . . 7
+ * 6 . . . . . . . . . 6       6 . . . . . . . . . 6
+ * 5 . . X . + . X . . 5       5 . . X . X . X . . 5
+ * 4 . . . . . . . . . 4       4 . . . . . . . . . 4
+ * 3 . . X . X . X . . 3       3 . . X . X . X . . 3
+ * 2 . . . . . . . . . 2       2 . . . . . . . . . 2
+ * 1 . . . . . . . . . 1       1 . . . . . . . . . 1
+ *   A B C D E F G H J           A B C D E F G H J  
+ *  
+ * For odd-sized boards larger than 9x9, the same pattern is followed,
+ * except that the edge stones are moved to the fourth line for 13x13
+ * boards and larger.
+ *
+ * For even-sized boards at least 8x8, only the four first diagrams
+ * are used, because there is no way to place the center stones
+ * symmetrically. As for odd-sized boards, the edge stones are moved
+ * to the fourth line for boards larger than 11x11.
+ *
+ * At most four stones are placed on 7x7 boards too (this size may or
+ * may not be supported by the rest of the engine). No handicap stones
+ * are ever placed on smaller boards.
+ *
+ * Notice that this function only deals with fixed handicap placement.
+ * Larger handicaps can be added by free placement if the used
+ * interface supports it.
+ */
+
+
+/* This table contains the (coded) positions of the stones.
+ *  2 maps to 2 or 3, depending on board size
+ *  0 maps to center
+ * -ve numbers map to  board_size - number
+ *
+ * The stones are placed in this order, *except* if there are
+ * 5 or 7 stones, in which case center ({0, 0}) is placed, and
+ * then as for 4 or 6.
+ */
+
+static const int places[][2] = {
+
+  {2, -2}, {-2, 2}, {2, 2}, {-2, -2}, /* first 4 are easy */
+                                      /* for 5, {0,0} is explicitly placed */
+  
+  {0, 2}, {0, -2},                    /* for 6 these two are placed */
+                                      /* for 7, {0,0} is explicitly placed */
+  
+  {2, 0}, {-2, 0},                    /* for 8, these two are placed */
+
+  {0, 0},                             /* finally tengen for 9 */
+};
+
+
+/*
+ * Sets up handicap stones, returning the number of placed handicap stones.
+ */
+
+int
+placehand(int handicap)
+{
+  int x;
+  int maxhand;
+  int three = board_size > 11 ? 3 : 2;
+  int mid = board_size/2;
+  int retval = handicap;
+
+  /* A handicap of 1 just means that B plays first, no komi.
+   * Black is not told where to play the first stone so no handicap
+   * is set. 
+   */
+  if (handicap < 2)
+    return 0;
+  if ((board_size % 2 == 1) && (board_size >= 9))
+    maxhand = 9;
+  else if (board_size >= 7)
+    maxhand = 4;
+  else
+    maxhand = 0;
+
+  /* It's up to the caller of this function to notice if the handicap
+   * was too large for fixed placement and act upon that.
+   */
+  if (handicap > maxhand) {
+    handicap = maxhand;
+    retval = maxhand;
+  }
+
+  /* special cases: 5 and 7 */
+  if (handicap == 5 || handicap == 7) {
+    add_stone(POS(mid, mid), BLACK);
+    handicap--;
+  }
+
+  for (x = 0; x < handicap; ++x) {
+    int i = places[x][0];
+    int j = places[x][1];
+
+    /* translate the encoded values to board co-ordinates */
+    if (i == 2)  i = three;    /* 2 or 3 */
+    if (i == -2) i = -three;
+
+    if (j == 2)  j = three;
+    if (j == -2) j = -three;
+
+    if (i == 0) i = mid;
+    if (j == 0) j = mid;
+
+    if (i < 0) i += board_size-1;
+    if (j < 0) j += board_size-1;
+
+    add_stone(POS(i, j), BLACK);
+  }
+
+  return retval;
+}
+
+
+/*
+ * Local Variables:
+ * tab-width: 8
+ * c-basic-offset: 2
+ * End:
+ */