Address C4244 warnings in MSVC

Making Displacement and Point operator*(float) use explicit casts because rounding is desirable.

Source/engine/displacement.hpp

@@ -44,8 +44,8 @@ struct Displacement {
 
 	constexpr Displacement &operator*=(const float factor)
 	{
-		deltaX *= factor;
-		deltaY *= factor;
+		deltaX = static_cast<int>(deltaX * factor);
+		deltaY = static_cast<int>(deltaY * factor);
 		return *this;
 	}
 

Source/engine/point.hpp

@@ -44,8 +44,8 @@ struct Point {
 
 	constexpr Point &operator*=(const float factor)
 	{
-		x *= factor;
-		y *= factor;
+		x = static_cast<int>(x * factor);
+		y = static_cast<int>(y * factor);
 		return *this;
 	}