Add AI/GS methods to get inflation factors

See: #415

docs/script-additions.html

@@ -95,5 +95,20 @@
 			<div class="methodtext">Checks whether the given road type is buildable by towns.</div>
 		</div>
 	</div>
+
+	<h3>Inflation: GSInflation Class and AIInflation Class</h3>
+	<div class="indent">
+		<h4>Static Public Member Functions:</h4>
+		<div class="indent">
+			<div class="code">static int64 GetPriceFactor ()</div>
+			<div class="methodtext">Get the inflation factor for prices.</div>
+			<div class="methodtext">Returns the inflation factor as a fixed point value (16 bits).</div>
+		</div>
+		<div class="indent">
+			<div class="code">static int64 GetPaymentFactor ()</div>
+			<div class="methodtext">Get the inflation factor for payments.</div>
+			<div class="methodtext">Returns the inflation factor as a fixed point value (16 bits).</div>
+		</div>
+	</div>
 </body>
 </html>

src/script/api/CMakeLists.txt

@@ -175,6 +175,7 @@ add_files(
     script_industrylist.hpp
     script_industrytype.hpp
     script_industrytypelist.hpp
+    script_inflation.hpp
     script_info_docs.hpp
     script_infrastructure.hpp
     script_list.hpp
@@ -246,6 +247,7 @@ add_files(
     script_industrylist.cpp
     script_industrytype.cpp
     script_industrytypelist.cpp
+    script_inflation.cpp
     script_infrastructure.cpp
     script_list.cpp
     script_log.cpp

src/script/api/script_inflation.cpp

@@ -0,0 +1,24 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD 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.
+ * OpenTTD 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 for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file script_inflation.cpp Implementation of ScriptInflation. */
+
+#include "../../stdafx.h"
+#include "script_inflation.hpp"
+#include "../../economy_func.h"
+
+#include "../../safeguards.h"
+
+/* static */ int64 ScriptInflation::GetPriceFactor()
+{
+	return _economy.inflation_prices;
+}
+
+/* static */ int64 ScriptInflation::GetPaymentFactor()
+{
+	return _economy.inflation_payment;
+}

src/script/api/script_inflation.hpp

@@ -0,0 +1,35 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD 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.
+ * OpenTTD 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 for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file script_inflation.hpp Inflation related code. */
+
+#ifndef SCRIPT_INFLATION_HPP
+#define SCRIPT_INFLATION_HPP
+
+#include "script_object.hpp"
+
+/**
+ * Class that handles inflation related functions.
+ * @api ai game
+ *
+ */
+class ScriptInflation : public ScriptObject {
+public:
+	/**
+	 * Get the inflation factor for prices.
+	 * @return Inflation factor, 16 bit fixed point.
+	 */
+	static int64 GetPriceFactor();
+
+	/**
+	 * Get the inflation factor for payments.
+	 * @return Inflation factor, 16 bit fixed point.
+	 */
+	static int64 GetPaymentFactor();
+};
+
+#endif /* SCRIPT_INFLATION_HPP */