Add modifier key for placing cable parts on the opposite side

src/generated/resources/assets/ae2/lang/en_us.json

@@ -961,6 +961,7 @@
   "key.ae2.category": "Applied Energistics 2",
   "key.ae2.guide": "Open Guide for Items",
   "key.ae2.mouse_wheel_item_modifier": "Modifier for Mouse-Wheel Items",
+  "key.ae2.part_placement_opposite": "Place Parts on Opposite Side",
   "key.ae2.portable_fluid_cell": "Open Portable Fluid Cell",
   "key.ae2.portable_item_cell": "Open Portable Item Cell",
   "key.ae2.wireless_terminal": "Open Wireless Terminal",

src/main/java/appeng/core/AppEngBase.java

@@ -59,6 +59,7 @@
 import appeng.api.stacks.AEKeyType;
 import appeng.api.stacks.AEKeyTypes;
 import appeng.api.stacks.AEKeyTypesInternal;
+import appeng.core.definitions.AEAttachmentTypes;
 import appeng.core.definitions.AEBlocks;
 import appeng.core.definitions.AEItems;
 import appeng.core.definitions.AEParts;
@@ -123,6 +124,7 @@ public AppEngBase(IEventBus modEventBus) {
 
         AEComponents.DR.register(modEventBus);
         InitStructures.register(modEventBus);
+        AEAttachmentTypes.register(modEventBus);
         modEventBus.addListener(this::registerRegistries);
         modEventBus.addListener(MainCreativeTab::initExternal);
         modEventBus.addListener(InitNetwork::init);

src/main/java/appeng/core/AppEngClient.java

@@ -87,9 +87,11 @@
 import appeng.client.render.effects.ParticleTypes;
 import appeng.client.render.effects.VibrantFX;
 import appeng.client.render.overlay.OverlayManager;
+import appeng.core.definitions.AEAttachmentTypes;
 import appeng.core.definitions.AEBlocks;
 import appeng.core.network.ServerboundPacket;
 import appeng.core.network.serverbound.MouseWheelPacket;
+import appeng.core.network.serverbound.PartPlacementOppositePacket;
 import appeng.helpers.IMouseWheelItem;
 import appeng.hooks.BlockAttackHook;
 import appeng.hooks.RenderBlockOutlineHook;
@@ -132,6 +134,10 @@ public class AppEngClient extends AppEngBase {
             "key.ae2.mouse_wheel_item_modifier", KeyConflictContext.IN_GAME, InputConstants.Type.KEYSYM,
             InputConstants.KEY_LSHIFT, "key.ae2.category");
 
+    private static final KeyMapping PART_PLACEMENT_OPPOSITE = new KeyMapping(
+            "key.ae2.part_placement_opposite", KeyConflictContext.IN_GAME, InputConstants.Type.KEYSYM,
+            InputConstants.KEY_LCONTROL, "key.ae2.category");
+
     private final Guide guide;
 
     public AppEngClient(IEventBus modEventBus) {
@@ -231,6 +237,7 @@ private void registerHotkeys(RegisterKeyMappingsEvent e) {
             e.register(OpenGuideHotkey.getHotkey());
         }
         e.register(MOUSE_WHEEL_ITEM_MODIFIER);
+        e.register(PART_PLACEMENT_OPPOSITE);
         Hotkeys.finalizeRegistration(e::register);
     }
 
@@ -271,6 +278,7 @@ private void clientSetup(FMLClientSetupEvent event) {
         });
 
         NeoForge.EVENT_BUS.addListener(this::wheelEvent);
+        NeoForge.EVENT_BUS.addListener(this::ctrlEvent);
         NeoForge.EVENT_BUS.register(OverlayManager.getInstance());
     }
 
@@ -330,6 +338,18 @@ private void wheelEvent(final InputEvent.MouseScrollingEvent me) {
         }
     }
 
+    private void ctrlEvent(InputEvent.Key event) {
+        if (event.getKey() == PART_PLACEMENT_OPPOSITE.getKey().getValue()) {
+            var player = Minecraft.getInstance().player;
+
+            if (player != null) {
+                var isDown = event.getAction() == InputConstants.PRESS;
+                player.setData(AEAttachmentTypes.HOLDING_CTRL, isDown);
+                PacketDistributor.sendToServer(new PartPlacementOppositePacket(isDown));
+            }
+        }
+    }
+
     public boolean shouldAddParticles(RandomSource r) {
         return switch (Minecraft.getInstance().options.particles().get()) {
             case ALL -> true;

src/main/java/appeng/core/definitions/AEAttachmentTypes.java

@@ -0,0 +1,22 @@
+package appeng.core.definitions;
+
+import java.util.function.Supplier;
+
+import net.neoforged.bus.api.IEventBus;
+import net.neoforged.neoforge.attachment.AttachmentType;
+import net.neoforged.neoforge.registries.DeferredRegister;
+import net.neoforged.neoforge.registries.NeoForgeRegistries;
+
+import appeng.core.AppEng;
+
+public final class AEAttachmentTypes {
+    private static final DeferredRegister<AttachmentType<?>> ATTACHMENT_TYPES = DeferredRegister
+            .create(NeoForgeRegistries.ATTACHMENT_TYPES, AppEng.MOD_ID);
+
+    public static final Supplier<AttachmentType<Boolean>> HOLDING_CTRL = ATTACHMENT_TYPES.register("ctrl",
+            () -> AttachmentType.builder(() -> false).build());
+
+    public static void register(IEventBus modEventBus) {
+        ATTACHMENT_TYPES.register(modEventBus);
+    }
+}

src/main/java/appeng/core/network/InitNetwork.java

@@ -36,6 +36,7 @@
 import appeng.core.network.serverbound.MEInteractionPacket;
 import appeng.core.network.serverbound.MouseWheelPacket;
 import appeng.core.network.serverbound.PartLeftClickPacket;
+import appeng.core.network.serverbound.PartPlacementOppositePacket;
 import appeng.core.network.serverbound.SelectKeyTypePacket;
 import appeng.core.network.serverbound.SwapSlotsPacket;
 import appeng.core.network.serverbound.SwitchGuisPacket;
@@ -78,6 +79,7 @@ public static void init(RegisterPayloadHandlersEvent event) {
         serverbound(registrar, SelectKeyTypePacket.TYPE, SelectKeyTypePacket.STREAM_CODEC);
         serverbound(registrar, SwapSlotsPacket.TYPE, SwapSlotsPacket.STREAM_CODEC);
         serverbound(registrar, SwitchGuisPacket.TYPE, SwitchGuisPacket.STREAM_CODEC);
+        serverbound(registrar, PartPlacementOppositePacket.TYPE, PartPlacementOppositePacket.STREAM_CODEC);
 
         // Bidirectional
         bidirectional(registrar, ConfigValuePacket.TYPE, ConfigValuePacket.STREAM_CODEC);

src/main/java/appeng/core/network/serverbound/PartPlacementOppositePacket.java

@@ -0,0 +1,40 @@
+package appeng.core.network.serverbound;
+
+import org.jetbrains.annotations.NotNull;
+
+import net.minecraft.network.RegistryFriendlyByteBuf;
+import net.minecraft.network.codec.StreamCodec;
+import net.minecraft.server.level.ServerPlayer;
+
+import appeng.core.definitions.AEAttachmentTypes;
+import appeng.core.network.CustomAppEngPayload;
+import appeng.core.network.ServerboundPacket;
+
+public record PartPlacementOppositePacket(boolean keyDown) implements ServerboundPacket {
+    public static final StreamCodec<RegistryFriendlyByteBuf, PartPlacementOppositePacket> STREAM_CODEC = StreamCodec
+            .ofMember(
+                    PartPlacementOppositePacket::write,
+                    PartPlacementOppositePacket::decode);
+
+    public static final Type<PartPlacementOppositePacket> TYPE = CustomAppEngPayload.createType("ctrl_down");
+
+    @NotNull
+    @Override
+    public Type<PartPlacementOppositePacket> type() {
+        return TYPE;
+    }
+
+    public static PartPlacementOppositePacket decode(RegistryFriendlyByteBuf buf) {
+        var keyDown = buf.readBoolean();
+        return new PartPlacementOppositePacket(keyDown);
+    }
+
+    public void write(RegistryFriendlyByteBuf data) {
+        data.writeBoolean(keyDown);
+    }
+
+    @Override
+    public void handleOnServer(ServerPlayer player) {
+        player.setData(AEAttachmentTypes.HOLDING_CTRL, keyDown);
+    }
+}

src/main/java/appeng/datagen/providers/localization/LocalizationProvider.java

@@ -128,6 +128,7 @@ private void generateLocalizations() {
         add("key.ae2.wireless_terminal", "Open Wireless Terminal");
         add("key.ae2.guide", "Open Guide for Items");
         add("key.ae2.mouse_wheel_item_modifier", "Modifier for Mouse-Wheel Items");
+        add("key.ae2.part_placement_opposite", "Place Parts on Opposite Side");
         add("key.toggle_focus.desc", "Toggle search box focus");
         add("stat.ae2.items_extracted", "Items extracted from ME Storage");
         add("stat.ae2.items_inserted", "Items added to ME Storage");

src/main/java/appeng/parts/PartPlacement.java

@@ -21,12 +21,12 @@
 import appeng.api.parts.IPartItem;
 import appeng.api.parts.PartHelper;
 import appeng.core.AELog;
+import appeng.core.definitions.AEAttachmentTypes;
 import appeng.parts.networking.CablePart;
 import appeng.util.Platform;
 import appeng.util.SettingsFrom;
 
 public class PartPlacement {
-
     public static InteractionResult place(UseOnContext context) {
 
         var player = context.getPlayer();
@@ -136,6 +136,10 @@ public static Placement getPartPlacement(@Nullable Player player,
             return replaceCablePlacement;
         }
 
+        if (player != null) {
+            side = player.getData(AEAttachmentTypes.HOLDING_CTRL) ? side.getOpposite() : side;
+        }
+
         if (canPlacePartOnBlock(player, level, partStack, pos, side)) {
             return new Placement(pos, side);
         }