Physics I guess

src/time/time.c

@@ -21,6 +21,9 @@ void timeInit(void) {
   // Set these to something non-zero.
   TIME.time = TIME_STEP;
   TIME.delta = TIME_STEP;
+
+  TIME.fixedDelta = TIME_STEP;
+  TIME.fixedTime = TIME_STEP;
 }
 
 void timeUpdate(void) {
@@ -36,4 +39,14 @@ void timeUpdate(void) {
   TIME.delta = delta;
   assertTrue(TIME.delta >= 0.0f, "Time delta is negative");
   TIME.time += TIME.delta;
+
+  // Perform a fixed time step.
+  if(TIME.time - TIME.fixedTime >= TIME_STEP) {
+    TIME.fixedUpdate = true;
+    TIME.fixedDelta = TIME_STEP;
+    TIME.fixedTime += TIME_STEP;
+  } else {
+    TIME.fixedDelta = 0.0f;
+    TIME.fixedUpdate = false;
+  }
 }

src/time/time.h

@@ -11,6 +11,10 @@
 typedef struct {
   float_t delta;
   float_t time;
+
+  bool_t fixedUpdate;
+  float_t fixedDelta;
+  float_t fixedTime;
 } dusktime_t;
 
 extern dusktime_t TIME;