Fixed empty category

core/src/mindustry/content/Blocks.java

@@ -1791,6 +1791,8 @@ public class Blocks{
 
         duct = new Duct("duct"){{
             requirements(Category.distribution, with(Items.graphite, 1));
+            //TODO bad idea? should this just require 1 beryllium?
+            buildVisibility = BuildVisibility.berylliumOnly;
             speed = 4f;
         }};
 

core/src/mindustry/ui/fragments/PlacementFragment.java

@@ -87,7 +87,7 @@ public class PlacementFragment extends Fragment{
     }
 
     void rebuild(){
-        currentCategory = Category.turret;
+        currentCategory = Category.distribution;
         Group group = toggler.parent;
         int index = toggler.getZIndex();
         toggler.remove();
@@ -400,6 +400,8 @@ public class PlacementFragment extends Fragment{
                         Seq<Block> blocks = getUnlockedByCategory(cat);
                         categoryEmpty[cat.ordinal()] = blocks.isEmpty();
                     }
+                    
+                    boolean needsAssign = categoryEmpty[currentCategory.ordinal()];
 
                     int f = 0;
                     for(Category cat : getCategories()){
@@ -409,6 +411,11 @@ public class PlacementFragment extends Fragment{
                             categories.image(Styles.black6);
                             continue;
                         }
+                        
+                        if(needsAssign){
+                            currentCategory = cat;
+                            needsAssign = false;
+                        }
 
                         categories.button(ui.getIcon(cat.name()), Styles.clearToggleTransi, () -> {
                             currentCategory = cat;

core/src/mindustry/world/meta/BuildVisibility.java

@@ -2,6 +2,7 @@ package mindustry.world.meta;
 
 import arc.func.*;
 import mindustry.*;
+import mindustry.content.*;
 
 public enum BuildVisibility{
     hidden(() -> false),
@@ -11,6 +12,7 @@ public enum BuildVisibility{
     sandboxOnly(() -> Vars.state == null || Vars.state.rules.infiniteResources),
     campaignOnly(() -> Vars.state == null || Vars.state.isCampaign()),
     lightingOnly(() -> Vars.state == null || Vars.state.rules.lighting || Vars.state.isCampaign()),
+    berylliumOnly(() -> !Vars.state.rules.hiddenBuildItems.contains(Items.beryllium)),
     ammoOnly(() -> Vars.state == null || Vars.state.rules.unitAmmo);
 
     private final Boolp visible;