From 80a6cf838a7a2c6c8276c71cc55c219ec7540b42 Mon Sep 17 00:00:00 2001
From: H.G.Muller <hgm@hgm-xboard.(none)>
Date: Tue, 10 Apr 2018 17:26:08 +0200
Subject: [PATCH] Allow overlapping promotions zones

The white and black contributions to the zone flags are now ORed into
zoneTab[], (which would already have been cleared when starting any new
variant), so that they won't erase each other.
---
 dropper.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/dropper.c b/dropper.c
index eaea10c..74e0ea8 100644
--- a/dropper.c
+++ b/dropper.c
@@ -580,8 +580,8 @@ GameInit (char *name)
     for(r=0; r<zone; r++) { // board-size table to indicate promotion zones and force-promotion zones
 	for(f=0; f<nrFiles; f++) {
 	    int xr = nrRanks - 1 - r, c = Z_MUST | COLOR | (r==0)*Z_LAST | (r<2 && v!=MINI_NR)*Z_2ND; // in mini-Shogi forelast not in zone
-	    zoneTab[22*r  + f] = Z_BLACK & c;
-	    zoneTab[22*xr + f] = Z_WHITE & c;
+	    zoneTab[22*r  + f] |= Z_BLACK & c;
+	    zoneTab[22*xr + f] |= Z_WHITE & c;
 	}
     }
 
-- 
1.7.0.4