Improve Windows compatibility

docs/windows.md

@@ -56,7 +56,13 @@ CMake, and choose `C:\Users\MyUser\open_spiel\open_spiel\CMakeLists.txt`. CMake
 will then run; once you see `CMake generation finished`, choose Build -> Build
 All. The files will be available in
 `C:\Users\MyUser\open_spiel\open_spiel\out\build\x64-Debug`, when the build
-completes with "Build All succeeded."
+completes with "Build All succeeded." 
+Extra compilation options may be necessary if errors occur.  
+MSVC options to deal with required C++ standard, file encoding (for chess characters) and large object files include `/std:c++17`,  `/utf-8`, `/bigobj`.
+To use them together with default MSVC arguments, you can use the follwing CMake command line arguments:
+```
+-DCMAKE_CXX_FLAGS="/std:c++17 /utf-8 /bigobj /DWIN32 /D_WINDOWS /GR /EHsc"
+```
 
 To be able to import the Python code (both the C++ binding `pyspiel` and the
 rest) from any location, you will need to add to your PYTHONPATH the root

open_spiel/games/bridge/bridge.cc

@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-
+#define NOMINMAX
 #include "open_spiel/games/bridge/bridge.h"
 
 #include <algorithm>

open_spiel/games/twixt/twixtboard.cc

@@ -386,9 +386,9 @@ void Board::AppendPegChar(std::string& s, Position position) const {
 void Board::AppendBeforeRow(std::string& s, Position position) const {
   // -1, +1
   int len = s.length();
-  AppendLinkChar(s, position + (Position){-1, 0}, kENE, "/");
-  AppendLinkChar(s, position + (Position){-1, -1}, kNNE, "/");
-  AppendLinkChar(s, position + (Position){0, 0}, kWNW, "_");
+  AppendLinkChar(s, position + Position{-1, 0}, kENE, "/");
+  AppendLinkChar(s, position + Position{-1, -1}, kNNE, "/");
+  AppendLinkChar(s, position + Position{0, 0}, kWNW, "_");
   if (len == s.length()) s.append(" ");
 
   //  0, +1
@@ -399,48 +399,48 @@ void Board::AppendBeforeRow(std::string& s, Position position) const {
 
   // +1, +1
   len = s.length();
-  AppendLinkChar(s, position + (Position){+1, 0}, kWNW, "\\");
-  AppendLinkChar(s, position + (Position){+1, -1}, kNNW, "\\");
-  AppendLinkChar(s, position + (Position){0, 0}, kENE, "_");
+  AppendLinkChar(s, position + Position{+1, 0}, kWNW, "\\");
+  AppendLinkChar(s, position + Position{+1, -1}, kNNW, "\\");
+  AppendLinkChar(s, position + Position{0, 0}, kENE, "_");
   if (len == s.length()) s.append(" ");
 }
 
 void Board::AppendPegRow(std::string& s, Position position) const {
   // -1, 0
   int len = s.length();
-  AppendLinkChar(s, position + (Position){-1, -1}, kNNE, "|");
-  AppendLinkChar(s, position + (Position){0, 0}, kWSW, "_");
+  AppendLinkChar(s, position + Position{-1, -1}, kNNE, "|");
+  AppendLinkChar(s, position + Position{0, 0}, kWSW, "_");
   if (len == s.length()) s.append(" ");
 
   //  0,  0
   AppendPegChar(s, position);
 
   // +1, 0
   len = s.length();
-  AppendLinkChar(s, position + (Position){+1, -1}, kNNW, "|");
-  AppendLinkChar(s, position + (Position){0, 0}, kESE, "_");
+  AppendLinkChar(s, position + Position{+1, -1}, kNNW, "|");
+  AppendLinkChar(s, position + Position{0, 0}, kESE, "_");
   if (len == s.length()) s.append(" ");
 }
 
 void Board::AppendAfterRow(std::string& s, Position position) const {
   // -1, -1
   int len = s.length();
-  AppendLinkChar(s, position + (Position){+1, -1}, kWNW, "\\");
-  AppendLinkChar(s, position + (Position){0, -1}, kNNW, "\\");
+  AppendLinkChar(s, position + Position{+1, -1}, kWNW, "\\");
+  AppendLinkChar(s, position + Position{0, -1}, kNNW, "\\");
   if (len == s.length()) s.append(" ");
 
   //  0, -1
   len = s.length();
-  AppendLinkChar(s, position + (Position){-1, -1}, kENE, "_");
-  AppendLinkChar(s, position + (Position){+1, -1}, kWNW, "_");
+  AppendLinkChar(s, position + Position{-1, -1}, kENE, "_");
+  AppendLinkChar(s, position + Position{+1, -1}, kWNW, "_");
   AppendLinkChar(s, position, kSSW, "|");
   if (len == s.length()) AppendLinkChar(s, position, kSSE, "|");
   if (len == s.length()) s.append(" ");
 
   // -1, -1
   len = s.length();
-  AppendLinkChar(s, position + (Position){-1, -1}, kENE, "/");
-  AppendLinkChar(s, position + (Position){0, -1}, kNNE, "/");
+  AppendLinkChar(s, position + Position{-1, -1}, kENE, "/");
+  AppendLinkChar(s, position + Position{0, -1}, kNNE, "/");
   if (len == s.length()) s.append(" ");
 }
 
@@ -514,7 +514,7 @@ void Board::SetPegAndLinks(Player player, Position position) {
       if (target_cell.color() == cell.color()) {
         // check if there are blocking links before setting link
         const std::set<Link>& blockers =
-            BlockerMap::GetBlockers((Link){position, dir});
+            BlockerMap::GetBlockers(Link{position, dir});
         bool blocked = false;
         for (auto& bl : blockers) {
           if (GetCell(bl.position).HasLink(bl.direction)) {

open_spiel/utils/file.cc

@@ -106,10 +106,15 @@ bool Exists(const std::string& path) {
 }
 
 std::string RealPath(const std::string& path) {
+#ifdef _WIN32
+  char real_path[MAX_PATH];
+  if (_fullpath(real_path, path.c_str(), MAX_PATH) == nullptr) {
+#else
   char real_path[PATH_MAX];
   if (realpath(path.c_str(), real_path) == nullptr) {
     // If there was an error return an empty path
-    return "";
+#endif
+      return "";
   }
 
   return std::string(real_path);