Integrate scaling and unscaling into Point.hpp

src/libslic3r/libslic3r.h

@@ -17,6 +17,7 @@
 #include <vector>
 #include <cassert>
 #include <cmath>
+#include <type_traits>
 
 #include "Technologies.hpp"
 #include "Semver.hpp"
@@ -247,6 +248,37 @@ static inline bool is_approx(Number value, Number test_value)
     return std::fabs(double(value) - double(test_value)) < double(EPSILON);
 }
 
+// A meta-predicate which is true for integers wider than or equal to coord_t
+template<class I> struct is_scaled_coord
+{
+    static const constexpr bool value =
+        std::is_integral<I>::value &&
+        std::numeric_limits<I>::digits >=
+            std::numeric_limits<coord_t>::digits;
+};
+
+// Meta predicates for floating, 'scaled coord' and generic arithmetic types
+// Can be used to restrict templates to work for only the specified set of types.
+// parameter T is the type we want to restrict
+// parameter O (Optional defaults to T) is the type that the whole expression
+// will be evaluated to.
+// e.g. template<class T> FloatingOnly<T, bool> is_nan(T val);
+// The whole template will be defined only for floating point types and the
+// return type will be bool.
+// For more info how to use, see docs for std::enable_if
+//
+template<class T, class O = T> 
+using FloatingOnly = std::enable_if_t<std::is_floating_point<T>::value, O>;
+
+template<class T, class O = T>
+using ScaledCoordOnly = std::enable_if_t<is_scaled_coord<T>::value, O>;
+
+template<class T, class O = T>
+using IntegerOnly = std::enable_if_t<std::is_integral<T>::value, O>;
+
+template<class T, class O = T>
+using ArithmeticOnly = std::enable_if_t<std::is_arithmetic<T>::value, O>;
+
 } // namespace Slic3r
 
 #endif