missing consts added

math/BufferedValue.h

@@ -16,7 +16,7 @@ public:
         last = current;
     }
 
-    T get(float lag) {
+    T get(float lag) const {
         return Math::interpolate(last, current, lag);
     }
 
@@ -51,26 +51,26 @@ public:
     }
 
     template<typename O>
-    auto operator+(const O& o) {
+    auto operator+(const O& o) const {
         return current + o;
     }
 
     template<typename O>
-    auto operator-(const O& o) {
+    auto operator-(const O& o) const {
         return current - o;
     }
 
     template<typename O>
-    auto operator*(const O& o) {
+    auto operator*(const O& o) const {
         return current * o;
     }
 
     template<typename O>
-    auto operator/(const O& o) {
+    auto operator/(const O& o) const {
         return current / o;
     }
 
-    auto operator-() {
+    auto operator-() const {
         return -current;
     }