fix: use chrono for time

src/main.cpp

@@ -49,6 +49,8 @@
 #include <skein/particle.h>
 #include <skein/particlemap.h>
 
+#include <chrono>
+
 // INPUT!
 //
 // what input do we even want in the first place?
@@ -84,6 +86,12 @@ void clearInput()
     input.cycleAnimation = false;
 }
 
+double getTime()
+{
+    auto now = std::chrono::steady_clock::now().time_since_epoch();
+    return std::chrono::duration<double>(now).count();
+}
+
 int main()
 {
     GLFWwindow* window = nullptr;
@@ -120,7 +128,8 @@ int main()
     const int ANIM_ORBITING     = 0;
     const int ANIM_ECCENTRICITY = 1;
     int animation = 0;
-    float time = glfwGetTime();
+
+    double time = getTime();
 
     // Main loop
     while (!glfwWindowShouldClose(window))
@@ -141,13 +150,14 @@ int main()
         }
 
         // only update time if playing the orbiting animation
+        const double speed = 0.5;
         if (animation == ANIM_ORBITING)
         {
-            time = glfwGetTime();
+            time = getTime() * speed;
         }
         else
         {
-            float e = .25 + .2 * sin(glfwGetTime());
+            double e = .25 + .2 * sin(getTime());
             orbit.setEccentricity(e);
         }