Block tech tree mods

core/src/io/anuke/mindustry/content/TechTree.java

@@ -13,6 +13,7 @@ public class TechTree implements ContentList{
 
     @Override
     public void load(){
+        TechNode.context = null;
         all = new Array<>();
 
         root = node(coreShard, () -> {
@@ -302,7 +303,7 @@ public class TechTree implements ContentList{
         });
     }
 
-    private TechNode node(Block block, Runnable children){
+    private static TechNode node(Block block, Runnable children){
         ItemStack[] requirements = new ItemStack[block.requirements.length];
         for(int i = 0; i < requirements.length; i++){
             requirements[i] = new ItemStack(block.requirements[i].item, 30 + block.requirements[i].amount * 6);
@@ -311,10 +312,15 @@ public class TechTree implements ContentList{
         return new TechNode(block, requirements, children);
     }
 
-    private TechNode node(Block block){
+    private static TechNode node(Block block){
         return node(block, () -> {});
     }
 
+    public static void create(Block parent, Block block){
+        TechNode.context = all.find(t -> t.block == parent);
+        node(block, () -> {});
+    }
+
     public static class TechNode{
         static TechNode context;
 
@@ -322,19 +328,22 @@ public class TechTree implements ContentList{
         public final ItemStack[] requirements;
         public final Array<TechNode> children = new Array<>();
 
-        TechNode(Block block, ItemStack[] requirements, Runnable children){
-            if(context != null){
-                context.children.add(this);
+        TechNode(TechNode ccontext, Block block, ItemStack[] requirements, Runnable children){
+            if(ccontext != null){
+                ccontext.children.add(this);
             }
 
             this.block = block;
             this.requirements = requirements;
 
-            TechNode last = context;
             context = this;
             children.run();
-            context = last;
+            context = ccontext;
             all.add(this);
         }
+
+        TechNode(Block block, ItemStack[] requirements, Runnable children){
+            this(context, block, requirements, children);
+        }
     }
 }