Merge branch 'master' into jgrpp

# Conflicts:
#	src/blitter/32bpp_anim.hpp
#	src/blitter/32bpp_base.hpp
#	src/blitter/8bpp_base.hpp
#	src/blitter/null.hpp
#	src/cheat_gui.cpp
#	src/gfx.cpp
#	src/linkgraph/linkgraph.cpp
#	src/spriteloader/grf.cpp
#	src/station_cmd.cpp

src/ground_vehicle.cpp

@@ -185,7 +185,7 @@ GroundVehicleAcceleration GroundVehicle<T, Type>::GetAcceleration()
 	}
 	/* Air drag; the air drag coefficient is in an arbitrary NewGRF-unit,
 	 * so we need some magic conversion factor. */
-	resistance += (area * this->gcache.cached_air_drag * speed * speed) / 1000;
+	resistance += static_cast<int64>(area) * this->gcache.cached_air_drag * speed * speed / 1000;
 
 	resistance += this->GetSlopeResistance();