Display Trades

src/main/java/com/github/sebseb7/autotrade/InitHandler.java

@@ -4,6 +4,7 @@ import com.github.sebseb7.autotrade.config.Configs;
 import com.github.sebseb7.autotrade.event.InputHandler;
 import com.github.sebseb7.autotrade.event.KeybindCallbacks;
 import com.github.sebseb7.autotrade.render.TraderHighlightRenderer;
+import com.github.sebseb7.autotrade.render.VillagerTradeOverlayRenderer;
 import fi.dy.masa.malilib.config.ConfigManager;
 import fi.dy.masa.malilib.config.options.ConfigString;
 import fi.dy.masa.malilib.event.InputEventHandler;
@@ -17,6 +18,7 @@ public class InitHandler implements IInitializationHandler {
 		ConfigManager.getInstance().registerConfigHandler(Reference.MOD_ID, new Configs());
 
 		TraderHighlightRenderer.register();
+		VillagerTradeOverlayRenderer.register();
 
 		InputHandler handler = new InputHandler();
 		InputEventHandler.getKeybindManager().registerKeybindProvider(handler);

src/main/java/com/github/sebseb7/autotrade/config/Configs.java

@@ -58,11 +58,14 @@ public class Configs implements IConfigHandler {
 				"true: Start the delay after the villager was unloaded; false: Start the delay after the trade has been initiated");
 		public static final ConfigInteger CONTAINER_CLOSE_DELAY = new ConfigInteger("containerCloseDelay", 0, 0,
 				30000000, "delay in ticks; to get signal from trapped chest");
+		public static final ConfigBoolean SHOW_TRADES = new ConfigBoolean("showTrades", true,
+				"Display villager/wandering-trader trades above their heads (requires trading with them once to cache the offers)");
 
 		public static final ImmutableList<IConfigValue> OPTIONS = ImmutableList.of(ENABLED, ITEM_FRAME, GLASS_BLOCK,
 				SELECTOR_OFFSET, ENABLE_SELL, SELL_ITEM, SELL_LIMIT, ENABLE_BUY, BUY_ITEM, BUY_LIMIT, MAX_INPUT_ITEMS,
 				INPUT_CONTAINER_X, INPUT_CONTAINER_Y, INPUT_CONTAINER_Z, OUTPUT_CONTAINER_X, OUTPUT_CONTAINER_Y,
-				OUTPUT_CONTAINER_Z, VOID_TRADING_DELAY, VOID_TRADING_DELAY_AFTER_TELEPORT, CONTAINER_CLOSE_DELAY);
+				OUTPUT_CONTAINER_Z, VOID_TRADING_DELAY, VOID_TRADING_DELAY_AFTER_TELEPORT, CONTAINER_CLOSE_DELAY,
+				SHOW_TRADES);
 	}
 
 	public static void loadFromFile() {

src/main/java/com/github/sebseb7/autotrade/event/AutoTradeClientTick.java

@@ -2,6 +2,7 @@ package com.github.sebseb7.autotrade.event;
 
 import com.github.sebseb7.autotrade.AutoTrade;
 import com.github.sebseb7.autotrade.config.Configs;
+import com.github.sebseb7.autotrade.render.VillagerTradeCache;
 import com.github.sebseb7.autotrade.util.TradeItemSpec;
 import fi.dy.masa.malilib.gui.Message;
 import fi.dy.masa.malilib.util.GuiUtils;
@@ -289,6 +290,12 @@ final class AutoTradeClientTick {
 			state = true;
 			MerchantMenu menu = screen.getMenu();
 			MerchantOffers offers = menu.getOffers();
+
+			// Cache offers for the in-world trade overlay.
+			Entity activeEntity = findEntityById(mc, villagerActive);
+			if (activeEntity != null && offers != null && !offers.isEmpty()) {
+				VillagerTradeCache.put(activeEntity.getUUID(), offers);
+			}
 			for (int i = 0; i < offers.size(); i++) {
 				MerchantOffer offer = offers.get(i);
 				int tradesLeft = offer.getMaxUses() - offer.getUses();

src/main/java/com/github/sebseb7/autotrade/render/VillagerTradeCache.java

@@ -0,0 +1,41 @@
+package com.github.sebseb7.autotrade.render;
+
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+import net.minecraft.world.item.trading.MerchantOffers;
+
+/**
+ * Client-side cache of villager/wandering-trader trade offers, keyed by entity
+ * UUID.
+ *
+ * <p>Populated by {@code AutoTradeClientTick} when the mod opens a merchant
+ * screen; consumed by {@link VillagerTradeOverlayRenderer} to draw trade labels
+ * above each villager's head.
+ */
+public final class VillagerTradeCache {
+	private static final Map<UUID, MerchantOffers> CACHE = new ConcurrentHashMap<>();
+
+	private VillagerTradeCache() {
+	}
+
+	/** Store (or update) the offers we observed for a given entity. */
+	public static void put(UUID entityUuid, MerchantOffers offers) {
+		CACHE.put(entityUuid, offers);
+	}
+
+	/** Retrieve cached offers, or {@code null} if we haven't seen this entity trade yet. */
+	public static MerchantOffers get(UUID entityUuid) {
+		return CACHE.get(entityUuid);
+	}
+
+	/** Remove a single entry (e.g. when the entity leaves render distance). */
+	public static void remove(UUID entityUuid) {
+		CACHE.remove(entityUuid);
+	}
+
+	/** Drop every cached entry (e.g. on world change). */
+	public static void clear() {
+		CACHE.clear();
+	}
+}

src/main/java/com/github/sebseb7/autotrade/render/VillagerTradeOverlayRenderer.java

@@ -0,0 +1,165 @@
+package com.github.sebseb7.autotrade.render;
+
+import com.github.sebseb7.autotrade.config.Configs;
+import com.mojang.blaze3d.vertex.PoseStack;
+import java.util.ArrayList;
+import java.util.List;
+import net.fabricmc.fabric.api.client.rendering.v1.level.LevelRenderContext;
+import net.fabricmc.fabric.api.client.rendering.v1.level.LevelRenderEvents;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.Font;
+import net.minecraft.client.renderer.MultiBufferSource;
+import net.minecraft.util.Mth;
+import net.minecraft.world.entity.Entity;
+import net.minecraft.world.entity.npc.villager.Villager;
+import net.minecraft.world.entity.npc.wanderingtrader.WanderingTrader;
+import net.minecraft.world.item.trading.MerchantOffer;
+import net.minecraft.world.item.trading.MerchantOffers;
+import net.minecraft.world.phys.Vec3;
+import org.joml.Matrix4f;
+
+/**
+ * Renders a compact summary of each villager's known trades above their head.
+ *
+ * <p>Trade data comes from {@link VillagerTradeCache}, which is populated when
+ * the mod opens a merchant screen.  Villagers whose trades haven't been seen
+ * yet show nothing.
+ */
+public final class VillagerTradeOverlayRenderer {
+
+	/** Vertical gap between successive trade lines (in world-space blocks). */
+	private static final float LINE_SPACING = 0.25F;
+
+	/** World-space scale of the text (vanilla name-tags use ~0.025). */
+	private static final float TEXT_SCALE = 0.02F;
+
+	/** Text background colour (semi-transparent dark). */
+	private static final int BG_COLOR = 0x80000000;
+
+	/** Normal trade text colour (white). */
+	private static final int TEXT_COLOR = 0xFFFFFFFF;
+
+	/** Depleted trade text colour (grey/red). */
+	private static final int DEPLETED_COLOR = 0xFFFF6666;
+
+	private VillagerTradeOverlayRenderer() {
+	}
+
+	public static void register() {
+		LevelRenderEvents.AFTER_SOLID_FEATURES.register(VillagerTradeOverlayRenderer::render);
+	}
+
+	private static void render(LevelRenderContext context) {
+		Minecraft mc = Minecraft.getInstance();
+		if (mc.level == null || mc.player == null) {
+			return;
+		}
+		if (!Configs.Generic.SHOW_TRADES.getBooleanValue()) {
+			return;
+		}
+
+		Font font = mc.font;
+		MultiBufferSource.BufferSource bufferSource = context.bufferSource();
+		Vec3 camera = mc.gameRenderer.getMainCamera().position();
+		float tickDelta = mc.getDeltaTracker().getGameTimeDeltaPartialTick(true);
+
+		for (Entity entity : mc.level.entitiesForRendering()) {
+			if (!(entity instanceof Villager) && !(entity instanceof WanderingTrader)) {
+				continue;
+			}
+			// Only render for villagers within a reasonable distance.
+			if (entity.distanceToSqr(mc.player) > 64.0 * 64.0) {
+				continue;
+			}
+
+			MerchantOffers offers = VillagerTradeCache.get(entity.getUUID());
+			if (offers == null || offers.isEmpty()) {
+				continue;
+			}
+
+			// Build compact trade lines: "CostA [+ CostB] → Result  (uses/max)"
+			List<TradeLineEntry> lines = buildTradeLines(offers);
+			if (lines.isEmpty()) {
+				continue;
+			}
+
+			// Interpolated entity position relative to camera.
+			double x = Mth.lerp(tickDelta, entity.xOld, entity.getX()) - camera.x;
+			double y = Mth.lerp(tickDelta, entity.yOld, entity.getY()) - camera.y;
+			double z = Mth.lerp(tickDelta, entity.zOld, entity.getZ()) - camera.z;
+
+			// Place the first line above the entity's head (entity height + small gap).
+			float baseY = entity.getBbHeight() + 0.6F;
+
+			PoseStack poseStack = new PoseStack();
+			poseStack.pushPose();
+			poseStack.translate(x, y + baseY, z);
+
+			// Face the camera (billboard).
+			poseStack.mulPose(mc.gameRenderer.getMainCamera().rotation());
+			poseStack.scale(-TEXT_SCALE, -TEXT_SCALE, TEXT_SCALE);
+
+			// Draw lines from top (highest index) to bottom (index 0).
+			for (int i = 0; i < lines.size(); i++) {
+				TradeLineEntry entry = lines.get(i);
+				float lineOffsetY = -(lines.size() - 1 - i) * (font.lineHeight + 2);
+
+				Matrix4f matrix = poseStack.last().pose();
+				matrix = new Matrix4f(matrix);
+				matrix.translate(0, lineOffsetY, 0);
+
+				int textWidth = font.width(entry.text);
+				float textX = -textWidth / 2.0F;
+
+				// Background
+				font.drawInBatch(entry.text, textX, 0, entry.color, false, matrix, bufferSource,
+						Font.DisplayMode.SEE_THROUGH, BG_COLOR, 0xF000F0);
+				// Foreground
+				font.drawInBatch(entry.text, textX, 0, entry.color, false, matrix, bufferSource,
+						Font.DisplayMode.NORMAL, 0, 0xF000F0);
+			}
+
+			poseStack.popPose();
+		}
+	}
+
+	private static List<TradeLineEntry> buildTradeLines(MerchantOffers offers) {
+		List<TradeLineEntry> lines = new ArrayList<>();
+		for (int i = 0; i < offers.size(); i++) {
+			MerchantOffer offer = offers.get(i);
+			StringBuilder sb = new StringBuilder();
+
+			// Cost A
+			if (!offer.getCostA().isEmpty()) {
+				sb.append(offer.getCostA().getCount()).append("× ")
+						.append(offer.getCostA().getHoverName().getString());
+			}
+
+			// Cost B (optional)
+			if (!offer.getCostB().isEmpty()) {
+				if (sb.length() > 0) {
+					sb.append(" + ");
+				}
+				sb.append(offer.getCostB().getCount()).append("× ")
+						.append(offer.getCostB().getHoverName().getString());
+			}
+
+			sb.append(" → ");
+
+			// Result
+			sb.append(offer.getResult().getCount()).append("× ")
+					.append(offer.getResult().getHoverName().getString());
+
+			// Remaining uses
+			int remaining = offer.getMaxUses() - offer.getUses();
+			sb.append("  (").append(remaining).append("/").append(offer.getMaxUses()).append(")");
+
+			boolean depleted = remaining <= 0;
+			lines.add(new TradeLineEntry(sb.toString(), depleted ? DEPLETED_COLOR : TEXT_COLOR));
+		}
+		return lines;
+	}
+
+	private record TradeLineEntry(String text, int color) {
+	}
+}