fps in window title

src/timer.c

@@ -0,0 +1,31 @@
+#include <sys/time.h>
+
+#include "types.h"
+
+Timer create_timer(const unsigned int target) {
+  Timer output = {
+      .counter = 0,
+      .target = target,
+  };
+
+  gettimeofday(&output.start, NULL);
+
+  return output;
+}
+
+bool inc_timer(Timer *timer) {
+  timer->counter += 1;
+  return timer->counter >= timer->target;
+}
+
+double reset_and_count(Timer *timer) {
+  struct timeval stop;
+  double secs, per_secs;
+  gettimeofday(&stop, NULL);
+  secs = (double)(stop.tv_usec - timer->start.tv_usec) / 1000000 +
+         (double)(stop.tv_sec - timer->start.tv_sec);
+  per_secs = ((float)timer->counter) / secs;
+  timer->start = stop;
+  timer->counter = 0;
+  return per_secs;
+}