ViaVersion VersionSwitcher for Minecraft Coder Pack (MCP)
If you encounter any issues, please report them on the
issue tracker.
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ViaVersion 4.10.0 did some changes to the ProtocolVersion API, you have to update your own code if you ever used the ViaLoadingBase class:
// Old
ViaLoadingBase.getInstance().getTargetVersion().isOlderThan(ProtocolVersion.v1_8);
ViaLoadingBase.getInstance().getTargetVersion().isNewerThan(ProtocolVersion.v1_8);
ViaLoadingBase.getInstance().getTargetVersion().isNewerThanOrEqualTo(ProtocolVersion.v1_8);
ViaLoadingBase.getInstance().getTargetVersion().isOlderThanOrEqualTo(ProtocolVersion.v1_8);
ViaLoadingBase.getInstance().getTargetVersion().getIndex();
// New
ViaLoadingBase.getInstance().getTargetVersion().olderThan(ProtocolVersion.v1_8);
ViaLoadingBase.getInstance().getTargetVersion().newerThan(ProtocolVersion.v1_8);
ViaLoadingBase.getInstance().getTargetVersion().newerThanOrEqualTo(ProtocolVersion.v1_8);
ViaLoadingBase.getInstance().getTargetVersion().olderThanOrEqualTo(ProtocolVersion.v1_8);
ViaLoadingBase.PROTOCOLS.indexOf(ViaLoadingBase.getInstance().getTargetVersion());
In addition to that, the ComparableProtocolVersion class has been removed and it's methods have been moved to the ProtocolVersion class.
Firstly, you will need to add the listed libraries into your dependencies in IntelliJ or Eclipse
Dependencies (Included inside libraries
folder)
downgraded-ViaVersion-[ver].jar > ViaVersion > https://github.com/ViaVersion/ViaVersion
downgraded-ViaBackwards-[ver].jar > ViaBackwards > https://github.com/ViaVersion/ViaBackwards
downgraded-ViaRewind-[ver].jar > ViaRewind > https://github.com/ViaVersion/ViaRewind
snakeyml-2.2.jar > SnakeYaml > https://bitbucket.org/snakeyaml/snakeyaml
Secondly, you need to add code that allows you to actually use ViaMCP (Choose the version folder that corresponds with your client version)
For other versions than 1.8.x and 1.12.2, you will need to modify the code to fit your client version. You can see namings for other major versions here
NOTE: ViaVersion 5.0.0+ doesn't support Java 8 anymore, therefore when updating the libraries yourself, you need to download the -Java8 jar files from the ci server or generate them yourself using this tool.
Add this to the main class of your client (aka injection function)
try {
ViaMCP.create();
// In case you want a version slider like in the Minecraft options, you can use this code here, please choose one of those:
ViaMCP.INSTANCE.initAsyncSlider(); // For top left aligned slider
ViaMCP.INSTANCE.initAsyncSlider(x, y, width (min. 110), height (recommended 20)); // For custom position and size slider
} catch (Exception e) {
e.printStackTrace();
}
You will need to modify 2 methods inside NetworkManager.java
1. Hook ViaVersion into the Netty Pipeline
Find the method, that is func_181124_a
, createNetworkManagerAndConnect
or contains (Bootstrap)((Bootstrap)((Bootstrap)(new Bootstrap()).group((EventLoopGroup)lazyloadbase.getValue())
Find the vanilla network pipeline call:
// 1.8.x client
p_initChannel_1_.pipeline().addLast((String)"timeout", (ChannelHandler)(new ReadTimeoutHandler(30))).addLast((String)"splitter", (ChannelHandler)(new MessageDeserializer2())).addLast((String)"decoder", (ChannelHandler)(new MessageDeserializer(EnumPacketDirection.CLIENTBOUND))).addLast((String)"prepender", (ChannelHandler)(new MessageSerializer2())).addLast((String)"encoder", (ChannelHandler)(new MessageSerializer(EnumPacketDirection.SERVERBOUND))).addLast((String)"packet_handler", (ChannelHandler)networkmanager);
// 1.12.x client
p_initChannel_1_.pipeline().addLast("timeout", new ReadTimeoutHandler(30)).addLast("splitter", new NettyVarint21FrameDecoder()).addLast("decoder", new NettyPacketDecoder(EnumPacketDirection.CLIENTBOUND)).addLast("prepender", new NettyVarint21FrameEncoder()).addLast("encoder", new NettyPacketEncoder(EnumPacketDirection.SERVERBOUND)).addLast("packet_handler", networkmanager);
After the vanilla network pipeline call, add the ViaMCP protocol pipeline hook:
if (p_initChannel_1_ instanceof SocketChannel && ViaLoadingBase.getInstance().getTargetVersion().getVersion() != ViaMCP.NATIVE_VERSION) {
final UserConnection user = new UserConnectionImpl(p_initChannel_1_, true);
new ProtocolPipelineImpl(user);
p_initChannel_1_.pipeline().addLast(new MCPVLBPipeline(user));
}
Your code should look like this afterwards (1.8.x for example), the vanilla network pipeline call should not be commented out and the ViaMCP protocol pipeline hook should be after the vanilla network pipeline call:
p_initChannel_1_.pipeline().addLast((String)"timeout", (ChannelHandler)(new ReadTimeoutHandler(30))).addLast((String)"splitter", (ChannelHandler)(new MessageDeserializer2())).addLast((String)"decoder", (ChannelHandler)(new MessageDeserializer(EnumPacketDirection.CLIENTBOUND))).addLast((String)"prepender", (ChannelHandler)(new MessageSerializer2())).addLast((String)"encoder", (ChannelHandler)(new MessageSerializer(EnumPacketDirection.SERVERBOUND))).addLast((String)"packet_handler", (ChannelHandler)networkmanager);
if (p_initChannel_1_ instanceof SocketChannel && ViaLoadingBase.getInstance().getTargetVersion().getVersion() != ViaMCP.NATIVE_VERSION) {
final UserConnection user = new UserConnectionImpl(p_initChannel_1_, true);
new ProtocolPipelineImpl(user);
p_initChannel_1_.pipeline().addLast(new MCPVLBPipeline(user));
}
2. Fix the compression in the NetworkManager#setCompressionTreshold function
Simply call the following code at the end of the method in Minecraft:
this.channel.pipeline().fireUserEventTriggered(new CompressionReorderEvent());
You will need to add a button to access the protocol switcher (or alternatively use the version slider under this section)
In addSingleplayerMultiplayerButtons()
function add (if in GuiMainMenu):
this.buttonList.add(new GuiButton(69, 5, 5, 90, 20, "Version"));
In actionPerformed()
function add:
if (button.id == 69)
{
this.mc.displayGuiScreen(new GuiProtocolSelector(this));
}
You can also use a version slider to control ViaMCP versions
this.buttonList.add(ViaMCP.INSTANCE.getAsyncVersionSlider());
Class: Minecraft.java
Function: clickMouse()
1.8.x
Replace this.thePlayer.swingItem();
on the 1st line in the if-clause with:
AttackOrder.sendConditionalSwing(this.objectMouseOver);
Replace this.playerController.attackEntity(this.thePlayer, this.objectMouseOver.entityHit);
in the switch in case ENTITY
with:
AttackOrder.sendFixedAttack(this.thePlayer, this.objectMouseOver.entityHit);
1.12.2
Replace this.player.swingArm(EnumHand.MAIN_HAND);
at the last line in the else if-clause with:
AttackOrder.sendConditionalSwing(this.objectMouseOver, EnumHand.MAIN_HAND);
Replace this.playerController.attackEntity(this.player, this.objectMouseOver.entityHit);
in the switch in case ENTITY
with:
AttackOrder.sendFixedAttack(this.thePlayer, this.objectMouseOver.entityHit, EnumHand.MAIN_HAND);
Block Placement
Replace all code in onItemUse
function in the ItemBlock
class with:
return FixedSoundEngine.onItemUse(this, stack, playerIn, worldIn, pos, side, hitX, hitY, hitZ);
Block Breaking
Replace all code in destroyBlock
function in the World
class with:
return FixedSoundEngine.destroyBlock(this, pos, dropBlock);
Call the fixTransactions();
in the ViaMCP
class file so ViaVersion doesn't remap anything in transaction packets.
After that, you need to do some changes in the Game code:
Class: S32PacketConfirmTransaction.java
Function: readPacketData()
Replace the code with this method:
public void readPacketData(PacketBuffer buf) throws IOException {
if (ViaLoadingBase.getInstance().getTargetVersion().newerThanOrEqualTo(ProtocolVersion.v1_17)) {
this.windowId = buf.readInt();
} else {
this.windowId = buf.readUnsignedByte();
this.actionNumber = buf.readShort();
this.accepted = buf.readBoolean();
}
}
Class: C0FPacketConfirmTransaction.java
Function: writePacketData()
Replace the code with this method:
public void writePacketData(PacketBuffer buf) throws IOException {
if (ViaLoadingBase.getInstance().getTargetVersion().newerThanOrEqualTo(ProtocolVersion.v1_17)) {
buf.writeInt(this.windowId);
} else {
buf.writeByte(this.windowId);
buf.writeShort(this.uid);
buf.writeByte(this.accepted ? 1 : 0);
}
}
Note: this code can be different depending on your mappings and game version, you just need to make sure it only reads the window id and doesn't read the rest of the packet because we previously removed the ViaVersion handlers which would have handled the rest of the packet.
Class: NetHandlerPlayClient.java
Function: handleConfirmTransaction()
Add this code after the checkThreadAndEnqueue function call:
if (ViaLoadingBase.getInstance().getTargetVersion().newerThanOrEqualTo(ProtocolVersion.v1_17)) {
this.addToSendQueue(new C0FPacketConfirmTransaction(packetIn.getWindowId(), 0, false));
return;
}
You can send raw packets with ViaMCP, you can use the following code to send raw packets:
final PacketWrapper blockPlace = PacketWrapper.create(ServerboundPackets1_9.PLAYER_BLOCK_PLACEMENT, null); // Replace null with your stored UserConnection, see NetworkManager tutorial above
blockPlace.write(Type.POSITION1_8, new Position(0, 0, 0)); // Replace with the block position
blockPlace.write(Type.VAR_INT, 0); // Replace with the block face, see https://wiki.vg/index.php?title=Protocol&oldid=7617#Player_Digging
blockPlace.write(Type.VAR_INT, 0); // Replace with the hand, 0 for main hand, 1 for off hand
blockPlace.write(Type.UNSIGNED_BYTE, (short) 0); // The x pos of the crosshair, from 0 to 15 increasing from west to east
blockPlace.write(Type.UNSIGNED_BYTE, (short) 0); // The y pos of the crosshair, from 0 to 15 increasing from bottom to top
blockPlace.write(Type.UNSIGNED_BYTE, (short) 0); // The z pos of the crosshair, from 0 to 15 increasing from north to south
try {
blockPlace.sendToServer(Protocol1_9To1_8.class); // Protocol class names are: server -> client version
} catch (Exception e) {
// Packet sending failed
throw new RuntimeException(e);
}
This should fix most peoples issues with dependencies (usually NoClassDefFoundError or ClassNotFoundException)
assets
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