feat: Offhand dynamic lights support

Author: FalsePattern

build.gradle.kts

@@ -302,4 +302,7 @@ dependencies {
     // LittleTiles 1.2.0
     compileOnly(deobfCurse("littletiles-257818:2462370"))
 //    runtimeOnlyNonPublishable(deobfCurse("creativecore-257814:2462369"))
+    compileOnly(deobfModrinth("backhand:1.4.1"))
+    compileOnly(deobfCurse("mb-battlegear-2-59710:2286765"))
+    compileOnly("com.github.GTNewHorizons:Battlegear2:1.4.3:dev")
 }

src/main/java/com/falsepattern/falsetweaks/FalseTweaks.java

@@ -27,6 +27,7 @@
 import lombok.val;
 import lombok.var;
 
+import net.minecraft.launchwrapper.Launch;
 import net.minecraft.util.EnumChatFormatting;
 import cpw.mods.fml.common.Loader;
 import cpw.mods.fml.common.Mod;
@@ -110,6 +111,12 @@ public void preInit(FMLPreInitializationEvent e) {
                     "Remove the DynamicLights mod and restart the game!\n" +
                     "FalseTweaks has built-in dynamic lights support.");
         }
+        try {
+            if (Launch.classLoader.getClassBytes("cn.tesseract.offhandlights.OffhandLights") != null) {
+                createSidedException("Remove the OffhandLights mod and restart the game!\n" +
+                                     "FalseTweaks has built-in offhand lights support.");
+            }
+        } catch (Throwable ignored) {}
         proxy.preInit(e);
     }
 

src/main/java/com/falsepattern/falsetweaks/modules/dynlights/base/DynamicLights.java

@@ -42,6 +42,7 @@
 import net.minecraft.entity.monster.EntityBlaze;
 import net.minecraft.entity.monster.EntityCreeper;
 import net.minecraft.entity.monster.EntityMagmaCube;
+import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.entity.projectile.EntityFireball;
 import net.minecraft.init.Blocks;
 import net.minecraft.init.Items;
@@ -326,12 +327,16 @@ public int getLightLevel(Entity entity) {
             }
 
             if (entity instanceof EntityLivingBase) {
-                EntityLivingBase player = (EntityLivingBase) entity;
-                ItemStack stackMain = player.getHeldItem();
+                EntityLivingBase living = (EntityLivingBase) entity;
+                ItemStack stackMain = living.getHeldItem();
                 int levelMain = getLightLevel(stackMain);
-                ItemStack stackHead = player.getEquipmentInSlot(4);
+                ItemStack stackHead = living.getEquipmentInSlot(4);
                 int levelHead = getLightLevel(stackHead);
-                return Math.max(levelMain, levelHead);
+                int level = Math.max(levelMain, levelHead);
+                if (entity instanceof EntityPlayer) {
+                    level = Math.max(level, getLightLevel(OffhandMod.CURRENT.getOffhandItem((EntityPlayer) entity)));
+                }
+                return level;
             } else if (entity instanceof EntityItem) {
                 EntityItem entityItem = (EntityItem) entity;
                 ItemStack itemStack = getItemStack(entityItem);

src/main/java/com/falsepattern/falsetweaks/modules/dynlights/base/OffhandMod.java

@@ -0,0 +1,76 @@
+/*
+ * This file is part of FalseTweaks.
+ *
+ * Copyright (C) 2022-2025 FalsePattern
+ * All Rights Reserved
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * FalseTweaks is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, only version 3 of the License.
+ *
+ * FalseTweaks is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with FalseTweaks. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.falsepattern.falsetweaks.modules.dynlights.base;
+
+import mods.battlegear2.api.core.IInventoryPlayerBattle;
+import mods.battlegear2.api.core.InventoryPlayerBattle;
+import xonin.backhand.api.core.BackhandUtils;
+
+import net.minecraft.entity.player.EntityPlayer;
+import net.minecraft.item.ItemStack;
+import net.minecraft.launchwrapper.Launch;
+import cpw.mods.fml.common.Loader;
+
+public enum OffhandMod {
+    None,
+    Backhand {
+        @Override
+        public ItemStack getOffhandItem(EntityPlayer player) {
+            return BackhandUtils.getOffhandItem(player);
+        }
+    },
+    Battlegear2 {
+        @Override
+        public ItemStack getOffhandItem(EntityPlayer player) {
+            return ((InventoryPlayerBattle) player.inventory).getCurrentOffhandWeapon();
+        }
+    },
+    Battlegear2GTNH {
+        @Override
+        public ItemStack getOffhandItem(EntityPlayer player) {
+            return ((IInventoryPlayerBattle) player.inventory).battlegear2$getCurrentOffhandWeapon();
+        }
+    };
+
+    public static final OffhandMod CURRENT = detectCurrent();
+
+    private static OffhandMod detectCurrent() {
+        if (Loader.isModLoaded("battlegear2")) {
+            try {
+                if (Launch.classLoader.getClassBytes("mods.battlegear2.api.core.InventoryPlayerBattle") != null) {
+                    return OffhandMod.Battlegear2;
+                }
+            } catch (Throwable ignored) {
+            }
+            return OffhandMod.Battlegear2GTNH;
+        }
+        if (Loader.isModLoaded("backhand")) {
+            return OffhandMod.Backhand;
+        }
+        return None;
+    }
+
+    public ItemStack getOffhandItem(EntityPlayer player) {
+        return null;
+    }
+}