Real-time lighting + solar system rendering

core/src/mindustry/game/Universe.java

@@ -1,7 +1,12 @@
 package mindustry.game;
 
 import arc.*;
+import arc.math.*;
 import arc.util.*;
+import mindustry.content.*;
+import mindustry.type.*;
+
+import static mindustry.Vars.*;
 
 public class Universe{
     private long seconds;
@@ -11,6 +16,22 @@ public class Universe{
         load();
     }
 
+    public void updateGlobal(){
+        //currently only updates one solar system
+        updatePlanet(Planets.sun);
+    }
+
+    private void updatePlanet(Planet planet){
+        planet.position.setZero();
+        planet.addParentOffset(planet.position);
+        if(planet.parent != null){
+            planet.position.add(planet.parent.position);
+        }
+        for(Planet child : planet.children){
+            updatePlanet(child);
+        }
+    }
+
     public void update(){
         secondCounter += Time.delta() / 60f;
         if(secondCounter >= 1){
@@ -22,6 +43,13 @@ public class Universe{
                 save();
             }
         }
+
+        //update sector light
+        float light = world.getSector().getLight();
+        float alpha = Mathf.clamp(Mathf.map(light, 0f, 0.8f, 0.1f, 1f));
+        //assign and map so darkness is not 100% dark
+        state.rules.ambientLight.a = 1f - alpha;
+        state.rules.lighting = !Mathf.equal(alpha, 1f);
     }
 
     public float secondsMod(float mod, float scale){