Initial commit

.gitignore

@@ -0,0 +1,4 @@
+/.gradle
+/.idea
+/build
+/run

LICENSE.txt

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2025 
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

build.gradle

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+plugins {
+    id 'fabric-loom' version '1.11-SNAPSHOT'
+    id 'maven-publish'
+}
+
+version = project.mod_version
+group = project.maven_group
+
+base {
+    archivesName = project.archives_base_name
+}
+
+
+repositories {
+    // Add repositories to retrieve artifacts from in here.
+    // You should only use this when depending on other mods because
+    // Loom adds the essential maven repositories to download Minecraft and libraries from automatically.
+    // See https://docs.gradle.org/current/userguide/declaring_repositories.html
+    // for more information about repositories.
+}
+
+dependencies {
+    // To change the versions see the gradle.properties file
+    minecraft "com.mojang:minecraft:${project.minecraft_version}"
+    mappings "net.fabricmc:yarn:${project.yarn_mappings}:v2"
+    modImplementation "net.fabricmc:fabric-loader:${project.loader_version}"
+
+    modImplementation "net.fabricmc.fabric-api:fabric-api:${project.fabric_version}"
+}
+
+processResources {
+    inputs.property "version", project.version
+    inputs.property "minecraft_version", project.minecraft_version
+    inputs.property "loader_version", project.loader_version
+    filteringCharset "UTF-8"
+
+    filesMatching("fabric.mod.json") {
+        expand "version": project.version,
+                "minecraft_version": project.minecraft_version,
+                "loader_version": project.loader_version
+    }
+}
+
+def targetJavaVersion = 21
+tasks.withType(JavaCompile).configureEach {
+    // ensure that the encoding is set to UTF-8, no matter what the system default is
+    // this fixes some edge cases with special characters not displaying correctly
+    // see http://yodaconditions.net/blog/fix-for-java-file-encoding-problems-with-gradle.html
+    // If Javadoc is generated, this must be specified in that task too.
+    it.options.encoding = "UTF-8"
+    if (targetJavaVersion >= 10 || JavaVersion.current().isJava10Compatible()) {
+        it.options.release.set(targetJavaVersion)
+    }
+}
+
+java {
+    def javaVersion = JavaVersion.toVersion(targetJavaVersion)
+    if (JavaVersion.current() < javaVersion) {
+        toolchain.languageVersion = JavaLanguageVersion.of(targetJavaVersion)
+    }
+    // Loom will automatically attach sourcesJar to a RemapSourcesJar task and to the "build" task
+    // if it is present.
+    // If you remove this line, sources will not be generated.
+    withSourcesJar()
+}
+
+jar {
+    from("LICENSE") {
+        rename { "${it}_${project.archivesBaseName}" }
+    }
+}
+
+// configure the maven publication
+publishing {
+    publications {
+        create("mavenJava", MavenPublication) {
+            artifactId = project.archives_base_name
+            from components.java
+        }
+    }
+
+    // See https://docs.gradle.org/current/userguide/publishing_maven.html for information on how to set up publishing.
+    repositories {
+        // Add repositories to publish to here.
+        // Notice: This block does NOT have the same function as the block in the top level.
+        // The repositories here will be used for publishing your artifact, not for
+        // retrieving dependencies.
+    }
+}

gradle.properties

@@ -0,0 +1,14 @@
+# Done to increase the memory available to gradle.
+org.gradle.jvmargs=-Xmx1G
+# Fabric Properties
+# check these on https://modmuss50.me/fabric.html
+minecraft_version=1.21.8
+yarn_mappings=1.21.8+build.1
+loader_version=0.17.2
+# Mod Properties
+mod_version=1.0
+maven_group=com.kasetoatz
+archives_base_name=biggerhotbar
+# Dependencies
+# check this on https://modmuss50.me/fabric.html
+fabric_version=0.131.0+1.21.8

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.14.1-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

gradlew

@@ -0,0 +1,251 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s\n' "$PWD" ) || exit
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH="\\\"\\\""
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        -jar "$APP_HOME/gradle/wrapper/gradle-wrapper.jar" \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"

gradlew.bat

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+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+@rem SPDX-License-Identifier: Apache-2.0
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

settings.gradle

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+pluginManagement {
+    repositories {
+        maven {
+            name = 'Fabric'
+            url = 'https://maven.fabricmc.net/'
+        }
+        gradlePluginPortal()
+    }
+}

src/main/java/com/kasetoatz/biggerhotbar/Biggerhotbar.java

@@ -0,0 +1,39 @@
+package com.kasetoatz.biggerhotbar;
+
+import net.fabricmc.api.ClientModInitializer;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.network.ClientPlayerEntity;
+import net.minecraft.client.network.ClientPlayerInteractionManager;
+import net.minecraft.entity.player.PlayerInventory;
+import net.minecraft.screen.slot.SlotActionType;
+
+import static com.kasetoatz.biggerhotbar.Manager.*;
+
+public class Biggerhotbar implements ClientModInitializer
+{
+    @Override
+    public void onInitializeClient()
+    {
+        load();
+    }
+
+    public static void flipItems()
+    {
+        toggleFlipped();
+        ClientPlayerEntity player = MinecraftClient.getInstance().player;
+        ClientPlayerInteractionManager manager = MinecraftClient.getInstance().interactionManager;
+        if (player == null || manager == null)
+        {
+            return;
+        }
+        for (int i = 0; i < 9; i++)
+        {
+            manager.clickSlot(player.playerScreenHandler.syncId, getSlotID(i + 27), i, SlotActionType.SWAP, player);
+        }
+    }
+
+    private static int getSlotID(int index)
+    {
+        return index < PlayerInventory.getHotbarSize() ? index + PlayerInventory.MAIN_SIZE : index;
+    }
+}

src/main/java/com/kasetoatz/biggerhotbar/Manager.java

@@ -0,0 +1,97 @@
+package com.kasetoatz.biggerhotbar;
+
+import com.fasterxml.jackson.databind.type.ArrayType;
+import com.google.common.reflect.TypeToken;
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.network.ServerInfo;
+import net.minecraft.util.WorldSavePath;
+import net.minecraft.util.crash.CrashException;
+import net.minecraft.util.crash.CrashReport;
+
+import java.io.IOException;
+import java.lang.reflect.Type;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+
+public class Manager
+{
+    private static final Path FILE = FabricLoader.getInstance().getConfigDir().resolve("bh_entries.json");
+    private static final Gson GSON = new GsonBuilder().setPrettyPrinting().create();
+    private static ArrayList<String> DATA = new ArrayList<>();
+
+    public static void load()
+    {
+        if (Files.exists(FILE))
+        {
+            try
+            {
+                String json = Files.readString(FILE);
+                Type type = new TypeToken<ArrayList<String>>(){}.getType();
+                DATA = GSON.fromJson(json, type);
+            }
+            catch (IOException exc)
+            {
+                throw new CrashException(CrashReport.create(exc, "Loading config file."));
+            }
+        }
+    }
+
+    private static void save()
+    {
+        try
+        {
+            Files.writeString(FILE, GSON.toJson(DATA));
+        }
+        catch (IOException exc)
+        {
+            throw new CrashException(CrashReport.create(exc, "Savinng config file."));
+        }
+    }
+
+    private static String getKey()
+    {
+        MinecraftClient client = MinecraftClient.getInstance();
+        ServerInfo info = client.getCurrentServerEntry();
+        if (info != null)
+        {
+            return info.address;
+        }
+        if (client.isInSingleplayer() && client.getServer() != null)
+        {
+            return client.getServer().getSavePath(WorldSavePath.ROOT).getParent().getFileName().toString();
+        }
+        return null;
+    }
+
+    public static boolean isFlipped()
+    {
+        String key = getKey();
+        if (key != null)
+        {
+            return DATA.contains(key);
+        }
+        return false;
+    }
+
+    public static void toggleFlipped()
+    {
+        String key = getKey();
+        if (key != null)
+        {
+            if (DATA.contains(key))
+            {
+                DATA.remove(key);
+            }
+            else
+            {
+                DATA.add(key);
+            }
+            save();
+        }
+    }
+}

src/main/java/com/kasetoatz/biggerhotbar/mixin/HandledScreenMixin.java

@@ -0,0 +1,123 @@
+package com.kasetoatz.biggerhotbar.mixin;
+
+import net.minecraft.client.gui.screen.ingame.CreativeInventoryScreen;
+import net.minecraft.client.gui.screen.ingame.HandledScreen;
+import net.minecraft.screen.slot.Slot;
+import net.minecraft.screen.slot.SlotActionType;
+import org.jetbrains.annotations.Nullable;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.*;
+import org.spongepowered.asm.mixin.injection.invoke.arg.Args;
+
+import static com.kasetoatz.biggerhotbar.Manager.isFlipped;
+
+@Mixin(HandledScreen.class)
+public abstract class HandledScreenMixin
+{
+    @Shadow @Nullable protected Slot focusedSlot;
+    @Shadow protected abstract void onMouseClick(Slot slot, int slotId, int button, SlotActionType actionType);
+
+    @Unique
+    private Slot customSlot(Slot slot)
+    {
+        if (isFlipped())
+        {
+            if ((Object)this instanceof CreativeInventoryScreen)
+            {
+                return slot;
+            }
+            int index = slot.getIndex();
+            if (index < 9)
+            {
+                return new Slot(slot.inventory, index, slot.x, slot.y - 22);
+            }
+            if (index > 26 && index < 36)
+            {
+                return new Slot(slot.inventory, index, slot.x, slot.y + 22);
+            }
+        }
+        return slot;
+    }
+
+    @Unique
+    private int highlightY(int y)
+    {
+        if (isFlipped() && focusedSlot != null)
+        {
+            if ((Object)this instanceof CreativeInventoryScreen)
+            {
+                return y;
+            }
+            int index = focusedSlot.getIndex();
+            if (index < 9)
+            {
+                return y - 22;
+            }
+            if (index > 26 && index < 36)
+            {
+                return y + 22;
+            }
+        }
+        return y;
+    }
+
+    @ModifyVariable(method="drawSlot", at=@At("HEAD"), argsOnly=true)
+    public Slot drawSlot(Slot slot)
+    {
+        return customSlot(slot);
+    }
+
+    @ModifyVariable(method="isPointOverSlot", at=@At("HEAD"), argsOnly=true)
+    public Slot isPointOverSlot(Slot slot)
+    {
+        return customSlot(slot);
+    }
+
+    @ModifyArg(method="drawSlotHighlightBack", at=@At(value="INVOKE", target="Lnet/minecraft/client/gui/DrawContext;drawGuiTexture(Lcom/mojang/blaze3d/pipeline/RenderPipeline;Lnet/minecraft/util/Identifier;IIII)V"), index=3)
+    public int highlightBackY(int y)
+    {
+        return highlightY(y);
+    }
+
+    @ModifyArg(method="drawSlotHighlightFront", at=@At(value="INVOKE", target="Lnet/minecraft/client/gui/DrawContext;drawGuiTexture(Lcom/mojang/blaze3d/pipeline/RenderPipeline;Lnet/minecraft/util/Identifier;IIII)V"), index=3)
+    public int highlightFrontY(int y)
+    {
+        return highlightY(y);
+    }
+
+    @ModifyArgs(method="handleHotbarKeyPressed", at=@At(value="INVOKE", target="Lnet/minecraft/client/gui/screen/ingame/HandledScreen;onMouseClick(Lnet/minecraft/screen/slot/Slot;IILnet/minecraft/screen/slot/SlotActionType;)V", ordinal=1))
+    public void keypress(Args args)
+    {
+        if ((Object)this instanceof CreativeInventoryScreen)
+        {
+            return;
+        }
+        if (isFlipped())
+        {
+            int src = args.get(1);
+            int dest = args.get(2);
+            args.set(0, null);
+            args.set(2, 0);
+            args.set(3, SlotActionType.PICKUP);
+            int source, destination;
+            if (src > 35 && src < 45)
+            {
+                source = dest + 27;
+                destination = src;
+            }
+            else
+            {
+                source = src;
+                destination = dest + 27;
+            }
+            onMouseClick(null, source, 0, SlotActionType.PICKUP);
+            if (source != destination)
+            {
+                onMouseClick(null, destination, 0, SlotActionType.PICKUP);
+            }
+            args.set(1, source);
+        }
+    }
+}

src/main/java/com/kasetoatz/biggerhotbar/mixin/InGameHudMixin.java

@@ -0,0 +1,82 @@
+package com.kasetoatz.biggerhotbar.mixin;
+
+import net.minecraft.client.gui.DrawContext;
+import net.minecraft.client.gui.hud.InGameHud;
+import net.minecraft.client.render.RenderTickCounter;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.Identifier;
+import org.jetbrains.annotations.Nullable;
+import org.spongepowered.asm.mixin.*;
+import org.spongepowered.asm.mixin.injection.*;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import static com.kasetoatz.biggerhotbar.Manager.isFlipped;
+
+@Mixin(InGameHud.class)
+public abstract class InGameHudMixin
+{
+    @Shadow @Final @Mutable private static Identifier HOTBAR_TEXTURE;
+    @Shadow protected abstract void renderHotbarItem(DrawContext context, int x, int y, RenderTickCounter tickCounter, PlayerEntity player, ItemStack stack, int seed);
+    @Shadow @Nullable protected abstract PlayerEntity getCameraPlayer();
+    @Unique private int centerX;
+
+    static
+    {
+        HOTBAR_TEXTURE = Identifier.of("biggerhotbar", "hotbar");
+    }
+
+    @ModifyConstant(method="renderHotbar", constant=@Constant(intValue=91))
+    private int hudOffset(int value)
+    {
+        return 182;
+    }
+
+    @ModifyConstant(method="renderHotbar", constant=@Constant(intValue=182))
+    private int hudWidth(int value)
+    {
+        return 362;
+    }
+
+    @ModifyConstant(method="renderHotbar", constant=@Constant(intValue=90))
+    private int itemPos(int value)
+    {
+        return 181;
+    }
+
+    @ModifyArg(method="renderHotbar", at=@At(value="INVOKE", target="Lnet/minecraft/entity/player/PlayerInventory;getStack(I)Lnet/minecraft/item/ItemStack;"))
+    public int modifyGetStack(int slot)
+    {
+        return isFlipped() ? slot + 27 : slot;
+    }
+
+    @Inject(method="renderHotbar", at=@At("TAIL"))
+    public void renderHotbar(DrawContext context, RenderTickCounter tickCounter, CallbackInfo ci)
+    {
+        PlayerEntity player = getCameraPlayer();
+        if (player == null)
+        {
+            return;
+        }
+        centerX = context.getScaledWindowWidth() / 2;
+        int posY = context.getScaledWindowHeight() - 19;
+        int start = isFlipped() ? 0 : 27;
+        int end = isFlipped() ? 9 : 36;
+        for (int i = start; i < end; i++)
+        {
+            int pos = centerX - 1 + (i - start) * 20 + 2;
+            renderHotbarItem(context, pos, posY, tickCounter, player, player.getInventory().getStack(i), i);
+        }
+    }
+
+    @ModifyArg(method="renderHotbar", at=@At(value="INVOKE", target="Lnet/minecraft/client/gui/DrawContext;drawGuiTexture(Lcom/mojang/blaze3d/pipeline/RenderPipeline;Lnet/minecraft/util/Identifier;IIII)V", ordinal=1), index=2)
+    private int customSelect(int value)
+    {
+        PlayerEntity player = getCameraPlayer();
+        if (player == null)
+        {
+            return value;
+        }
+        return isFlipped() ? centerX - 183 + (player.getInventory().getSelectedSlot() + 9) * 20 : value;
+    }
+}

src/main/java/com/kasetoatz/biggerhotbar/mixin/MouseMixin.java

@@ -0,0 +1,34 @@
+package com.kasetoatz.biggerhotbar.mixin;
+
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.Mouse;
+import net.minecraft.client.network.ClientPlayerEntity;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.ModifyArg;
+
+import static com.kasetoatz.biggerhotbar.Biggerhotbar.flipItems;
+
+@Mixin(Mouse.class)
+public abstract class MouseMixin
+{
+    @Shadow @Final private MinecraftClient client;
+
+    @ModifyArg(method="onMouseScroll", at=@At(value="INVOKE", target="Lnet/minecraft/entity/player/PlayerInventory;setSelectedSlot(I)V"), index=0)
+    private int onMouseScroll(int slot)
+    {
+        ClientPlayerEntity player = client.player;
+        if (player == null)
+        {
+            return slot;
+        }
+        int old = player.getInventory().getSelectedSlot();
+        if ((old == 8 && slot == 0) || (old == 0 && slot == 8))
+        {
+            flipItems();
+        }
+        return slot;
+    }
+}

src/main/java/com/kasetoatz/biggerhotbar/mixin/PlayerInventoryMixin.java

@@ -0,0 +1,44 @@
+package com.kasetoatz.biggerhotbar.mixin;
+
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.network.ClientPlayerEntity;
+import net.minecraft.client.network.ClientPlayerInteractionManager;
+import net.minecraft.entity.player.PlayerInventory;
+import net.minecraft.item.ItemStack;
+import net.minecraft.screen.slot.SlotActionType;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+import static com.kasetoatz.biggerhotbar.Manager.isFlipped;
+
+@Mixin(PlayerInventory.class)
+public abstract class PlayerInventoryMixin
+{
+    @Shadow public abstract ItemStack getStack(int slot);
+
+    @Inject(method="addStack(ILnet/minecraft/item/ItemStack;)I", at=@At(value ="INVOKE", target="Lnet/minecraft/entity/player/PlayerInventory;setStack(ILnet/minecraft/item/ItemStack;)V", shift=At.Shift.AFTER))
+    public void addStack(int slot, ItemStack stack, CallbackInfoReturnable<Integer> cir)
+    {
+        boolean flipped = isFlipped() && slot < 9;
+        if ((slot > 8 && slot < 27) || flipped)
+        {
+            for (int i = 27; i < 36; i++)
+            {
+                if (getStack(i).isEmpty())
+                {
+                    ClientPlayerEntity player = MinecraftClient.getInstance().player;
+                    ClientPlayerInteractionManager manager = MinecraftClient.getInstance().interactionManager;
+                    if (player == null || manager == null)
+                    {
+                        return;
+                    }
+                    manager.clickSlot(player.playerScreenHandler.syncId, flipped ? slot + 36 : slot, 0, SlotActionType.PICKUP, player);
+                    manager.clickSlot(player.playerScreenHandler.syncId, i, 0, SlotActionType.PICKUP, player);
+                }
+            }
+        }
+    }
+}

src/main/resources/biggerhotbar.mixins.json

@@ -0,0 +1,18 @@
+{
+  "required": true,
+  "minVersion": "0.8",
+  "package": "com.kasetoatz.biggerhotbar.mixin",
+  "compatibilityLevel": "JAVA_21",
+  "client": [
+    "HandledScreenMixin",
+    "InGameHudMixin",
+    "MouseMixin",
+    "PlayerInventoryMixin"
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  },
+  "overwrites": {
+    "requireAnnotations": true
+  }
+}

src/main/resources/fabric.mod.json

@@ -0,0 +1,24 @@
+{
+  "schemaVersion": 1,
+  "id": "biggerhotbar",
+  "version": "${version}",
+  "name": "BiggerHotbar",
+  "description": "",
+  "authors": [],
+  "contact": {},
+  "license": "MIT",
+  "environment": "client",
+  "entrypoints": {
+    "client": [
+      "com.kasetoatz.biggerhotbar.Biggerhotbar"
+    ]
+  },
+  "mixins": [
+    "biggerhotbar.mixins.json"
+  ],
+  "depends": {
+    "fabricloader": ">=${loader_version}",
+    "fabric": "*",
+    "minecraft": "${minecraft_version}"
+  }
+}