Made default CacheLayer add method insert before 'normal'

core/src/mindustry/graphics/CacheLayer.java

@@ -18,8 +18,16 @@ public class CacheLayer{
 
     public int id;
 
-    /** Register a new CacheLayer. */
+    /** Registers cache layers that will render before the 'normal' layer. */
     public static void add(CacheLayer... layers){
+        for(var layer : layers){
+            //7 = 'normal' index
+            add(7, layer);
+        }
+    }
+
+    /** Register CacheLayers at the end of the array. This will render over "normal" tiles. This is likely not the method you want to use. */
+    public static void addLast(CacheLayer... layers){
         int newSize = all.length + layers.length;
         var prev = all;
         //reallocate the array and copy everything over; performance matters very little here anyway
@@ -43,11 +51,15 @@ public class CacheLayer{
         System.arraycopy(prev, index, all, index + 1, prev.length - index);
 
         all[index] = layer;
+
+        for(int i = 0; i < all.length; i++){
+            all[i].id = i;
+        }
     }
 
     /** Loads default cache layers. */
     public static void init(){
-        add(
+        addLast(
             water = new ShaderLayer(Shaders.water),
             mud = new ShaderLayer(Shaders.mud),
             tar = new ShaderLayer(Shaders.tar),