Merged change from 1.2 to add X11 path for OpenGL detection

test/configure.in

@@ -68,6 +68,21 @@ AM_PATH_SDL($SDL_VERSION,
 CFLAGS="$CFLAGS $SDL_CFLAGS"
 LIBS="$LIBS $SDL_LIBS"
 
+dnl Check for X11 path, needed for OpenGL on some systems
+AC_PATH_X
+if test x$have_x = xyes; then
+    if test x$ac_x_includes = xno || test x$ac_x_includes = x; then
+        :
+    else
+        CFLAGS="$CFLAGS -I$ac_x_includes"
+    fi
+    if test x$ac_x_libraries = xno || test x$ac_x_libraries = x; then
+        :
+    else
+        XPATH="-L$ac_x_libraries"
+    fi
+fi
+
 dnl Check for OpenGL
 AC_MSG_CHECKING(for OpenGL support)
 have_opengl=no
@@ -80,7 +95,7 @@ have_opengl=yes
 AC_MSG_RESULT($have_opengl)
 if test x$have_opengl = xyes; then
     CFLAGS="$CFLAGS -DHAVE_OPENGL"
-    GLLIB="$SYS_GL_LIBS"
+    GLLIB="$XPATH $SYS_GL_LIBS"
 else
     GLLIB=""
 fi