diff --git a/core/src/mindustry/core/GameState.java b/core/src/mindustry/core/GameState.java
index 668fbd0b71..4ffc24dd06 100644
--- a/core/src/mindustry/core/GameState.java
+++ b/core/src/mindustry/core/GameState.java
@@ -59,7 +59,7 @@ public class GameState{
     }
 
     public boolean hasSpawns(){
-        return rules.waves && !(isCampaign() && rules.attackMode);
+        return rules.waves && ((rules.waveTeam.cores().size > 0 && rules.attackMode) || rules.spawns.size > 0);
     }
 
     /** Note that being in a campaign does not necessarily mean having a sector. */
diff --git a/core/src/mindustry/ui/dialogs/ResearchDialog.java b/core/src/mindustry/ui/dialogs/ResearchDialog.java
index b22315dfc5..762051b93d 100644
--- a/core/src/mindustry/ui/dialogs/ResearchDialog.java
+++ b/core/src/mindustry/ui/dialogs/ResearchDialog.java
@@ -381,11 +381,9 @@ public class ResearchDialog extends BaseDialog{
             this.parent = parent;
             this.width = this.height = nodeSize;
             nodes.add(this);
-            if(node.children != null){
-                children = new TechTreeNode[node.children.size];
-                for(int i = 0; i < children.length; i++){
-                    children[i] = new TechTreeNode(node.children.get(i), this);
-                }
+            children = new TechTreeNode[node.children.size];
+            for(int i = 0; i < children.length; i++){
+                children[i] = new TechTreeNode(node.children.get(i), this);
             }
         }
     }
diff --git a/core/src/mindustry/ui/layout/TreeLayout.java b/core/src/mindustry/ui/layout/TreeLayout.java
index 6de2442bcf..a4ee3ac419 100644
--- a/core/src/mindustry/ui/layout/TreeLayout.java
+++ b/core/src/mindustry/ui/layout/TreeLayout.java
@@ -11,7 +11,7 @@ public interface TreeLayout{
         public T parent;
 
         //internal stuff
-        public float mode, prelim, change, shift;
+        public float mode, prelim, change, shift, cachedWidth = -1f;
         public int number = -1, leaves;
         public TreeNode thread, ancestor;
 
@@ -21,12 +21,13 @@ public interface TreeLayout{
 
         public float calcWidth(){
             if(children == null) return width;
+            if(cachedWidth > 0) return cachedWidth;
 
             float cWidth = 0;
             for(T node : children){
                 cWidth += node.calcWidth();
             }
-            return Math.max(width, cWidth);
+            return cachedWidth = Math.max(width, cWidth);
         }
     }
 }