8. 同步比分并绘制 HUD
前面的比赛逻辑全部在服务器运行。本章在屏幕顶部显示地图 ID、红蓝比分和当前阶段。客户端保存一份展示快照，服务器继续负责规则判断。
定义传输数据
创建 ScoreS2CPacket.java：
ScoreS2CPacket.java
package com.example.elimination;
import net.minecraft.network.FriendlyByteBuf;
import net.minecraftforge.network.NetworkEvent;
import java.util.function.Consumer;
import java.util.function.Supplier;
public record ScoreS2CPacket(String mapName, int red, int blue, String phase) {
// Installed during physical client setup; the signature contains no client classes.
public static Consumer<ScoreS2CPacket> receiver = packet -> {};
public static void encode(ScoreS2CPacket packet, FriendlyByteBuf buf) {
buf.writeUtf(packet.mapName, 48);
buf.writeVarInt(packet.red);
buf.writeVarInt(packet.blue);
buf.writeUtf(packet.phase, 32);
}
public static ScoreS2CPacket decode(FriendlyByteBuf buf) {
return new ScoreS2CPacket(buf.readUtf(48), buf.readVarInt(), buf.readVarInt(), buf.readUtf(32));
}
public void handle(Supplier<NetworkEvent.Context> supplier) {
NetworkEvent.Context context = supplier.get();
context.enqueueWork(() -> receiver.accept(this));
context.setPacketHandled(true);
}
}
包只保存字符串和数字。写入与读取顺序一致，并限制字符串长度。handle() 将处理切回客户端主线程；receiver 由下面的客户端入口安装，公共包类无需引用 Minecraft。
注册独立频道
EliminationNetwork.java
package com.example.elimination;
import net.ptcrys.fpsmatch.common.packet.register.NetworkPacketRegister;
import net.minecraft.resources.ResourceLocation;
import net.minecraftforge.network.NetworkDirection;
public final class EliminationNetwork {
public static final NetworkPacketRegister PACKETS = new NetworkPacketRegister(
new ResourceLocation(EliminationMod.MODID, "main"), "1");
public static void register() {
PACKETS.registerPacket(ScoreS2CPacket.class, NetworkDirection.PLAY_TO_CLIENT);
}
}
在上一章 EliminationMod.setup() 的 enqueueWork 回调中，保留能力注册并添加 EliminationNetwork.register();。频道和消息注册发生在公共初始化阶段，两端使用相同顺序。明确声明 PLAY_TO_CLIENT，使这个展示包只能从服务器发往客户端。
从地图发送快照
在 EliminationMap 中添加：
EliminationMap.java
public void syncToClient() {
if (getServerLevel().getGameTime() % 20 != 0) return;
String phase = isStart() && roundLifecycle != null
? roundLifecycle.phase().name().toLowerCase(java.util.Locale.ROOT) : "idle";
ScoreS2CPacket packet = new ScoreS2CPacket(getMapName(), red.getScores(), blue.getScores(), phase);
getMapTeams().getOnlineWithSpec().forEach(player ->
EliminationNetwork.PACKETS.getChannel().send(
net.minecraftforge.network.PacketDistributor.PLAYER.with(() -> player), packet));
}
地图每 tick 末尾会调用 syncToClient()。本例每 20 tick 发一次完整快照，包含参赛者和旁观者，重连者也会收到下一份快照。这里使用附属模组自己的频道发送，不能把注册在独立频道的包交给 FPSMatch 内置频道。
为使教学代码直接可读，先采用定期全量发送。需要更及时或更省流量时，可以在入场时发送初始快照，在比分或阶段变化时推送增量。
安装客户端接收器
创建仅在物理客户端加载的 EliminationClient.java：
EliminationClient.java
package com.example.elimination;
import net.minecraft.client.Minecraft;
import net.minecraft.network.chat.Component;
import net.minecraftforge.api.distmarker.Dist;
import net.minecraftforge.client.event.ClientPlayerNetworkEvent;
import net.minecraftforge.client.event.RegisterGuiOverlaysEvent;
import net.minecraftforge.common.MinecraftForge;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.common.Mod;
import net.minecraftforge.fml.event.lifecycle.FMLClientSetupEvent;
@Mod.EventBusSubscriber(modid = EliminationMod.MODID, value = Dist.CLIENT,
bus = Mod.EventBusSubscriber.Bus.MOD)
public final class EliminationClient {
private static ScoreS2CPacket latest;
private static long receivedAt;
@SubscribeEvent
public static void setup(FMLClientSetupEvent event) {
event.enqueueWork(() -> {
ScoreS2CPacket.receiver = packet -> {
latest = packet;
receivedAt = System.nanoTime();
};
MinecraftForge.EVENT_BUS.addListener(EliminationClient::logout);
});
}
private static void logout(ClientPlayerNetworkEvent.LoggingOut event) { latest = null; }
@SubscribeEvent
public static void overlays(RegisterGuiOverlaysEvent event) {
event.registerAboveAll("elimination_score", (gui, graphics, partialTick, width, height) -> {
Minecraft minecraft = Minecraft.getInstance();
if (latest == null || minecraft.player == null || minecraft.options.hideGui
|| System.nanoTime() - receivedAt > 2_000_000_000L) return;
Component text = Component.translatable("hud.elimination.score", latest.mapName(),
latest.red(), latest.blue(),
Component.translatable("phase.elimination." + latest.phase()));
graphics.drawCenteredString(minecraft.font, text, width / 2, 12, 0xFFFFFF);
});
}
}
FMLClientSetupEvent 和 RegisterGuiOverlaysEvent 订阅 MOD 总线，离开服务器事件订阅 Forge 总线。value = Dist.CLIENT 将包含 Minecraft 的类限制在物理客户端。
收到包时更新 latest，覆盖层只读取这份快照。断开连接时清空数据；离开地图后如果两秒没有新快照，HUD 自动隐藏。因此本例离场显示最多延迟两秒；需要立即隐藏的界面可增加明确的离场消息。
添加语言文件
resources/assets/elimination_addon/lang/zh_cn.json 中包含：
{
"hud.elimination.score": "%s | 红 %s : 蓝 %s | %s",
"phase.elimination.waiting": "准备",
"phase.elimination.active_round": "进行中",
"phase.elimination.round_end_waiting": "回合结算",
"phase.elimination.paused": "暂停",
"phase.elimination.idle": "未开始"
}
把条目合并到已有语言文件，保留前面章节的播报文案。drawCenteredString 使用 GUI 缩放后的宽度定位文字，hideGui 使 HUD 随 F1 一起隐藏。
继续扩展
同一个工程已经贯通地图、队伍、回合、设置、能力、网络与客户端展示。接下来可阅读HUD 与客户端状态、客户端操作请求或资源与本地化。