diff --git a/source/tools/atlas/GameInterface/Handlers/MapHandlers.cpp b/source/tools/atlas/GameInterface/Handlers/MapHandlers.cpp
index 4a4ff52c53..b627655f67 100644
--- a/source/tools/atlas/GameInterface/Handlers/MapHandlers.cpp
+++ b/source/tools/atlas/GameInterface/Handlers/MapHandlers.cpp
@@ -86,10 +86,10 @@ QUERYHANDLER(GenerateMap)
 
 	CScriptValRooted settings;
 	scriptInterface.Eval("({})", settings);
-	scriptInterface.SetProperty(settings.get(), "Size", (size_t)msg->size);
-	scriptInterface.SetProperty(settings.get(), "Seed", (size_t)msg->seed);
+	scriptInterface.SetProperty(settings.get(), "Size", (int)msg->size);
+	scriptInterface.SetProperty(settings.get(), "Seed", (int)msg->seed);
 	scriptInterface.SetProperty(settings.get(), "BaseTerrain", std::vector<std::wstring>(*msg->terrain));
-	scriptInterface.SetProperty(settings.get(), "BaseHeight", (size_t)msg->height);
+	scriptInterface.SetProperty(settings.get(), "BaseHeight", (int)msg->height);
 	scriptInterface.SetProperty(settings.get(), "CircularMap", true);	// now default to circular map
 
 	CScriptValRooted pData = scriptInterface.ParseJSON(*msg->playerData);
diff --git a/source/tools/atlas/GameInterface/Messages.h b/source/tools/atlas/GameInterface/Messages.h
index 1812d3f028..67c5c9becf 100644
--- a/source/tools/atlas/GameInterface/Messages.h
+++ b/source/tools/atlas/GameInterface/Messages.h
@@ -134,10 +134,10 @@ MESSAGE(ResizeScreen,
 
 QUERY(GenerateMap,
 		((std::wstring, script))				// name of script
-		((size_t, size))						// size in number of patches
-		((size_t, seed))						// seed for rng
+		((int, size))							// size in number of patches
+		((int, seed))							// seed for rng
 		((std::vector<std::wstring>, terrain))	// base terrain(s)
-		((size_t, height))						// base height
+		((int, height))							// base height
 		((std::string, playerData))				// JSON player data
 		,
 		((int, status))							// Status code, 0 for success, or < 0 for failure