Not everything was in the SDL namespace.

Author: CodenameLambda

clock.hh

@@ -4,15 +4,17 @@
 #include <chrono>
 
 
-class Clock {
-    decltype(std::chrono::system_clock::now()) last;
-    bool first;
+namespace SDL {
+    class Clock {
+        decltype(std::chrono::system_clock::now()) last;
+        bool first;
 
-    public:
-    Clock();
+        public:
+        Clock();
 
-    std::chrono::milliseconds tick();
-    std::chrono::milliseconds tick(const float fps);
-};
+        std::chrono::milliseconds tick();
+        std::chrono::milliseconds tick(const float fps);
+    };
+}
 
 #endif