API can add text to HUD and health bars.

src/main/java/com/provismet/provihealth/ProviHealthClient.java

@@ -5,6 +5,7 @@
 
 import com.provismet.provihealth.api.ProviHealthApi;
 import com.provismet.provihealth.config.Options;
+import com.provismet.provihealth.hud.BorderRegistry;
 import com.provismet.provihealth.hud.TargetHealthBar;
 import com.provismet.provihealth.particle.Particles;
 
@@ -36,6 +37,7 @@ public void onInitializeClient () {
                 }
             }
         );
+        BorderRegistry.sortTitles();
 
         Options.load();
         Particles.register();

src/main/java/com/provismet/provihealth/api/ProviHealthApi.java

@@ -1,6 +1,8 @@
 package com.provismet.provihealth.api;
 
+import net.minecraft.entity.LivingEntity;
 import net.minecraft.registry.tag.TagKey;
+import net.minecraft.text.Text;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -209,4 +211,22 @@ public default boolean registerPortrait (EntityType<?> type, @Nullable Identifie
     public default boolean registerPortrait (EntityType<?> type, @Nullable Identifier resource, int priority) {
         return BorderRegistry.registerBorder(type, resource, priority);
     }
+
+    /**
+     * Registers a function that places text on the healthbars or the HUD.
+     * Text can be used to place additional information about an entity on the HUD or the in-world healthbar.
+     * Text appears line-by-line on the HUD and in-world healthbar. Separate lines should be registered separately.
+     * The lambda is given context for whether it is appearing on the in-world or the HUD render.
+     *
+     * @param titleLambda Function of (LivingEntity entity, boolean isWorld, boolean isHUD) -> Text. Should return null if no text is wanted.
+     * @param order Determines the order of this line of text. Higher numbers appear at the top.
+     */
+    public default void registerTitle (TitleGenerator titleLambda, int order) {
+        BorderRegistry.registerTitle(titleLambda, order);
+    }
+
+    @FunctionalInterface
+    public interface TitleGenerator {
+        public Text apply (LivingEntity entity, boolean isWorld, boolean isHUD);
+    }
 }

src/main/java/com/provismet/provihealth/compat/ProviHealthConfigScreen.java

@@ -76,6 +76,13 @@ public static Screen build (Screen parent) {
             .build()
         );
 
+        hud.addEntry(entryBuilder.startBooleanToggle(Text.translatable("entry.provihealth.hudTitles"), Options.hudTitles)
+            .setDefaultValue(true)
+            .setTooltip(Text.translatable("tooltip.provihealth.hudTitles"))
+            .setSaveConsumer(newValue -> Options.hudTitles = newValue)
+            .build()
+        );
+
         hud.addEntry(entryBuilder.startBooleanToggle(Text.translatable("entry.provihealth.gradient"), Options.hudGradient)
             .setDefaultValue(false)
             .setTooltip(Text.translatable("tooltip.provihealth.gradient"))
@@ -181,6 +188,13 @@ public static Screen build (Screen parent) {
             .build()
         );
 
+        health.addEntry(entryBuilder.startBooleanToggle(Text.translatable("entry.provihealth.worldTitles"), Options.worldTitles)
+            .setDefaultValue(true)
+            .setTooltip(Text.translatable("tooltip.provihealth.worldTitles"))
+            .setSaveConsumer(newValue -> Options.worldTitles = newValue)
+            .build()
+        );
+
         health.addEntry(entryBuilder.startBooleanToggle(Text.translatable("entry.provihealth.gradient"), Options.worldGradient)
             .setDefaultValue(false)
             .setTooltip(Text.translatable("tooltip.provihealth.gradient"))

src/main/java/com/provismet/provihealth/compat/SelfApiHook.java

@@ -3,7 +3,6 @@
 import com.provismet.provihealth.ProviHealthClient;
 import com.provismet.provihealth.api.ProviHealthApi;
 
-import net.minecraft.entity.EntityType;
 import net.minecraft.item.Items;
 import net.minecraft.registry.tag.EntityTypeTags;
 

src/main/java/com/provismet/provihealth/config/Options.java

@@ -58,6 +58,7 @@ public class Options {
     public static Vector3f unpackedStartHud = Vec3d.unpackRgb(hudStartColour).toVector3f();
     public static Vector3f unpackedEndHud = Vec3d.unpackRgb(hudEndColour).toVector3f();
     public static boolean hudGradient = false;
+    public static boolean hudTitles = true;
 
     public static boolean showTextInWorld = true;
     public static float maxRenderDistance = 24f;
@@ -70,6 +71,7 @@ public class Options {
     public static boolean overrideLabels = false;
     public static boolean worldShadows = true;
     public static float worldOffsetY = 0f;
+    public static boolean worldTitles = true;
 
     public static boolean spawnDamageParticles = true;
     public static boolean spawnHealingParticles = false;
@@ -163,10 +165,12 @@ public static void save () {
             .append("playerTarget", playersVisibilityOverride).newLine()
             .append("otherHealth", others.name()).newLine()
             .append("otherTarget", othersVisibilityOverride).newLine()
+            .append("worldTitles", worldTitles).newLine()
             .append("bossHUD", bossHUD.name()).newLine()
             .append("hostileHUD", hostileHUD.name()).newLine()
             .append("playerHUD", playerHUD.name()).newLine()
             .append("otherHUD", otherHUD.name()).newLine()
+            .append("hudTitles", hudTitles).newLine()
             .append("damageParticles", spawnDamageParticles).newLine()
             .append("healingParticles", spawnHealingParticles).newLine()
             .append("damageColour", damageColour).newLine()
@@ -319,6 +323,10 @@ public static void load () {
                         playersVisibilityOverride = parser.nextBoolean();
                         break;
 
+                    case "worldTitles":
+                        worldTitles = parser.nextBoolean();
+                        break;
+
                     case "playerHUD":
                         playerHUD = HUDType.valueOf(parser.nextString());
                         break;
@@ -335,6 +343,10 @@ public static void load () {
                         otherHUD = HUDType.valueOf(parser.nextString());
                         break;
 
+                    case "hudTitles":
+                        hudTitles = parser.nextBoolean();
+                        break;
+
                     case "damageParticles":
                         spawnDamageParticles = parser.nextBoolean();
                         break;

src/main/java/com/provismet/provihealth/hud/BorderRegistry.java

@@ -1,8 +1,13 @@
 package com.provismet.provihealth.hud;
 
+import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.HashMap;
+import java.util.List;
 
+import com.provismet.provihealth.api.ProviHealthApi;
 import net.minecraft.registry.tag.TagKey;
+import net.minecraft.text.Text;
 import org.jetbrains.annotations.Nullable;
 
 import com.provismet.provihealth.ProviHealthClient;
@@ -21,6 +26,8 @@ public class BorderRegistry {
     private static final HashMap<EntityType<?>, BorderPriority> typeBorderPriorities = new HashMap<>();
     private static final HashMap<EntityType<?>, ItemPriority> typeIconPriorities = new HashMap<>();
 
+    private static final List<TitlePriority> orderedTitles = new ArrayList<>();
+
     private static final Identifier DEFAULT = ProviHealthClient.identifier("textures/gui/healthbars/default.png");
 
     public static boolean registerBorder (TagKey<EntityType<?>> entityTag, @Nullable Identifier border, int priority) {
@@ -71,6 +78,19 @@ else if (typeIconPriorities.containsKey(type) && priority <= typeIconPriorities.
         return true;
     }
 
+    public static void registerTitle (ProviHealthApi.TitleGenerator titleGen, int order) {
+        orderedTitles.add(new TitlePriority(titleGen, order));
+    }
+
+    public static void sortTitles () {
+        orderedTitles.sort(new Comparator<TitlePriority>() {
+            @Override
+            public int compare (TitlePriority a, TitlePriority b) {
+                return a.order() - b.order();
+            }
+        });
+    }
+
     public static Identifier getBorder (@Nullable LivingEntity entity) {
         if (entity == null || !Options.useCustomHudPortraits) return DEFAULT;
         else {
@@ -118,6 +138,14 @@ public static ItemStack getItem (LivingEntity entity) {
         return bestIcon;
     }
 
+    public static List<Text> getTitle (LivingEntity entity, boolean world, boolean hud) {
+        if (entity == null) return null;
+
+        List<Text> titles = orderedTitles.stream().map(title -> title.titleGetter().apply(entity, world, hud)).filter(title -> title != null).toList();
+        return titles;
+    }
+
     private record ItemPriority (ItemStack itemStack, int priority) {}
     private record BorderPriority (Identifier borderId, int priority) {}
+    private record TitlePriority (ProviHealthApi.TitleGenerator titleGetter, int order) {}
 }

src/main/java/com/provismet/provihealth/hud/TargetHealthBar.java

@@ -27,6 +27,8 @@
 import net.minecraft.util.Identifier;
 import net.minecraft.util.math.MathHelper;
 
+import java.util.List;
+
 public class TargetHealthBar implements HudRenderCallback {
     public static boolean disabledLabels = false;
 
@@ -149,9 +151,31 @@ public void onHudRender (DrawContext drawContext, float tickDelta) {
 
                     if (expectedLeftPixel < armourX) expectedLeftPixel = armourX + 10;
 
-                    int mountHealthX = drawContext.drawText(MinecraftClient.getInstance().textRenderer, mountHealthString, expectedLeftPixel, BAR_Y + BAR_HEIGHT + (vehicleMaxHealthDeep > 0f ? MOUNT_BAR_HEIGHT : 0) + 2, 0xFFFFFF, true);
+                    int mountHealthX = drawContext.drawText(MinecraftClient.getInstance().textRenderer, mountHealthString, expectedLeftPixel, BAR_Y + BAR_HEIGHT + MOUNT_BAR_HEIGHT + 2, 0xFFFFFF, true);
                     drawContext.drawTexture(MOUNT_HEART, mountHealthX, BAR_Y + BAR_HEIGHT + MOUNT_BAR_HEIGHT + 1, 9, 9, 0f, 0f, 9, 9, 9, 9);
                 }
+
+                // Render titles on HUD
+                if (Options.hudTitles) {
+                    List<Text> titles = BorderRegistry.getTitle(this.target, false, true).reversed();
+
+                    int titleX = 5;
+                    int titleY = OFFSET_Y + FRAME_LENGTH + 5;
+
+                    if (Options.hudPosition == HUDPosition.LEFT) {
+                        for (Text title : titles) {
+                            drawContext.drawText(MinecraftClient.getInstance().textRenderer, title, titleX, titleY, 0xFFFFFF, true);
+                            titleY += 10;
+                        }
+                    }
+                    else {
+                        for (Text title : titles) {
+                            titleX = MinecraftClient.getInstance().getWindow().getScaledWidth() - 10 - MinecraftClient.getInstance().textRenderer.getWidth(title);
+                            drawContext.drawText(MinecraftClient.getInstance().textRenderer, title, titleX, titleY, 0xFFFFFF, true);
+                            titleY += 10;
+                        }
+                    }
+                }
             }
 
             if (hudType != HUDType.NONE) {

src/main/java/com/provismet/provihealth/world/EntityHealthBar.java

@@ -8,6 +8,7 @@
 import com.provismet.provihealth.ProviHealthClient;
 import com.provismet.provihealth.config.Options;
 import com.provismet.provihealth.config.Options.SeeThroughText;
+import com.provismet.provihealth.hud.BorderRegistry;
 import com.provismet.provihealth.interfaces.IMixinLivingEntity;
 import com.provismet.provihealth.util.Visibility;
 
@@ -31,6 +32,8 @@
 import net.minecraft.util.Identifier;
 import net.minecraft.util.math.MathHelper;
 
+import java.util.List;
+
 public class EntityHealthBar {
     private static final Identifier BARS = ProviHealthClient.identifier("textures/gui/healthbars/in_world.png");
     private static final Identifier COMPAT_BARS = ProviHealthClient.identifier("textures/gui/healthbars/in_world_coloured.png");
@@ -107,46 +110,60 @@ public static void render (Entity entity, float tickDelta, MatrixStack matrices,
             Matrix4f textModel = matrices.peek().getPositionMatrix();
             final TextRenderer textRenderer = MinecraftClient.getInstance().textRenderer;
             final String healthString = String.format("%d/%d", Math.round(target.getHealth()), Math.round(target.getMaxHealth()));
+            final float lineHeight = 9;
+
+            List<Text> titles = List.of(); // initialise an empty list
+            if (Options.worldTitles) titles = BorderRegistry.getTitle(target, true, false);
 
             if (Options.overrideLabels) {
                 final Text targetName = getName(target);
                 final float targetNameWidth = textRenderer.getWidth(targetName);
 
-                float healthX = 50f - textRenderer.getWidth(healthString);
-                final float healthY = -9;
-                float nameX = -50;
-                float nameY = -9;
-                boolean wrapLines = targetNameWidth - 50f > healthX - 2f;
+                // 0 is in the centre.
+                final float leftmost = -50f;
+                final float rightmost = -leftmost;
+
+                float healthX = rightmost - textRenderer.getWidth(healthString);
+                final float healthY = -lineHeight;
+                float nameX = leftmost;
+                float nameY = -lineHeight;
+                boolean wrapLines = targetNameWidth - rightmost > healthX - 2f;
 
                 if (wrapLines) {
                     healthX = (healthX - 50) / 2f;
                     nameX = -targetNameWidth / 2f;
-                    nameY -= 9;
+                    nameY -= lineHeight;
                 }
 
-                if (target.shouldRenderName() && !target.isSneaky() && Options.seeThroughTextType != SeeThroughText.NONE) {
+                if ((target.shouldRenderName() || (target.hasCustomName() && target == MinecraftClient.getInstance().targetedEntity)) && !target.isSneaky() && Options.seeThroughTextType != SeeThroughText.NONE) {
                     if (Options.seeThroughTextType == SeeThroughText.STANDARD) {
                         if (Options.worldShadows) {
-                            textRenderer.draw(targetName, nameX + 1, nameY + 1, 0x404040, false, textModel, vertexConsumers, TextLayerType.NORMAL, 0, light);
-                            textRenderer.draw(healthString, healthX + 1, healthY + 1, 0x404040, false, textModel, vertexConsumers, TextLayerType.NORMAL, 0, light);
+                            EntityHealthBar.renderFullText(textRenderer, targetName, healthString, titles, nameX + 1, nameY + 1, healthX + 1, healthY + 1, lineHeight, 1, 0x404040, false, textModel, vertexConsumers, TextLayerType.NORMAL, light);
                         }
 
                         matrices.translate(0, 0, 0.03f);
                         textModel = matrices.peek().getPositionMatrix();
-                        textRenderer.draw(targetName, nameX, nameY, 0xFFFFFF, false, textModel, vertexConsumers, TextLayerType.SEE_THROUGH, 0, light);
-                        textRenderer.draw(healthString, healthX, healthY, 0xFFFFFF, false, textModel, vertexConsumers, TextLayerType.SEE_THROUGH, 0, light);
+                        EntityHealthBar.renderFullText(textRenderer, targetName, healthString, titles, nameX, nameY, healthX, healthY, lineHeight, 0, 0xFFFFFF, false, textModel, vertexConsumers, TextLayerType.SEE_THROUGH, light);
                     }
                     else {
-                        textRenderer.draw(targetName, nameX, nameY, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.SEE_THROUGH, 0, light);
-                        textRenderer.draw(healthString, healthX, healthY, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.SEE_THROUGH, 0, light);
+                        EntityHealthBar.renderFullText(textRenderer, targetName, healthString, titles, nameX, nameY, healthX, healthY, lineHeight, 0, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.SEE_THROUGH, light);
                     }
                 }
                 else {
-                    textRenderer.draw(targetName, nameX, nameY, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.NORMAL, 0, light);
-                    textRenderer.draw(healthString, healthX, healthY, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.NORMAL, 0, light);
+                    EntityHealthBar.renderFullText(textRenderer, targetName, healthString, titles, nameX, nameY, healthX, healthY, lineHeight, 0, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.NORMAL, light);
+                }
+            }
+            else {
+                textRenderer.draw(healthString, -(textRenderer.getWidth(healthString)) / 2f, -lineHeight, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.NORMAL, 0, light);
+
+                float titleX;
+                float titleY = -lineHeight;
+                for (Text title : titles) {
+                    titleX = -textRenderer.getWidth(title) / 2f;
+                    titleY -= lineHeight;
+                    textRenderer.draw(title, titleX, titleY, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.NORMAL, 0, light);
                 }
             }
-            else textRenderer.draw(healthString, -(textRenderer.getWidth(healthString)) / 2f, -10, 0xFFFFFF, Options.worldShadows, textModel, vertexConsumers, TextLayerType.NORMAL, 0, light);
             matrices.pop();
         }
 
@@ -155,6 +172,19 @@ public static void render (Entity entity, float tickDelta, MatrixStack matrices,
         matrices.pop();
     }
 
+    private static void renderFullText (TextRenderer textRenderer, Text name, String health, List<Text> titles, float nameX, float nameY, float healthX, float healthY, float titleLineHeight, float titleLineOffset, int colour, boolean shadow, Matrix4f model, VertexConsumerProvider vertexes, TextLayerType layerType, int light) {
+        textRenderer.draw(name, nameX, nameY, colour, shadow, model, vertexes, layerType, 0, light);
+        textRenderer.draw(health, healthX, healthY, colour, shadow, model, vertexes, layerType, 0, light);
+
+        float titleX;
+        float titleY = nameY;
+        for (Text title : titles) {
+            titleX = titleLineOffset - (textRenderer.getWidth(title) / 2f);
+            titleY -= titleLineHeight;
+            textRenderer.draw(title, titleX, titleY, colour, shadow, model, vertexes, layerType, 0, light);
+        }
+    }
+
     @SuppressWarnings("resource")
     private static Text getName (LivingEntity entity) {
         if (entity instanceof PlayerEntity && entity.isInvisibleTo(MinecraftClient.getInstance().player)) return Text.translatable("entity.provihealth.unknownPlayer");