highlight selection points

src/main/java/me/youhavetrouble/blockedit/BEPlayer.java

@@ -1,5 +1,7 @@
 package me.youhavetrouble.blockedit;
 
+import me.youhavetrouble.blockedit.optionals.SelectionHighlight;
+import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.entity.Player;
 import org.bukkit.util.BoundingBox;
@@ -12,6 +14,15 @@ public class BEPlayer {
     private static final HashMap<UUID, BEPlayer> playerHashMap = new HashMap<>();
     private BoundingBox selection;
     private Location selectionPoint1, selectionPoint2;
+    private final UUID playerUuid;
+
+    public BEPlayer(Player player) {
+        this.playerUuid = player.getUniqueId();
+    }
+
+    public Player getPlayer() {
+        return Bukkit.getPlayer(playerUuid);
+    }
 
     public BoundingBox getSelection() {
         return selection;
@@ -19,6 +30,7 @@ public class BEPlayer {
 
     public void resetSelection() {
         this.selection = null;
+        Bukkit.getScheduler().runTaskAsynchronously(BlockEdit.getPlugin(),() -> SelectionHighlight.sendStop(getPlayer()));
     }
 
     private void updateSelection() {
@@ -34,6 +46,19 @@ public class BEPlayer {
             selection = null;
             return;
         }
+
+        Bukkit.getScheduler().runTaskAsynchronously(BlockEdit.getPlugin(), () -> {
+            SelectionHighlight.sendStop(getPlayer());
+            if (selectionPoint1.equals(selectionPoint2)) {
+                SelectionHighlight.highlightBlock(getPlayer(), selectionPoint1, "#ffffff", "Selection Points", 10000);
+            } else {
+                SelectionHighlight.highlightBlock(getPlayer(), selectionPoint1, "#ffffff", "Selection Point 1", 10000);
+                SelectionHighlight.highlightBlock(getPlayer(), selectionPoint2, "#ffffff", "Selection Point 2", 10000);
+            }
+
+        });
+
+
         selection = BoundingBox.of(selectionPoint1, selectionPoint2);
         // bounding boxes are dumb.
         selection.expand(0.5, 0.5, 0.5);
@@ -75,7 +100,7 @@ public class BEPlayer {
     }
 
     protected static void addPlayer(Player player) {
-        playerHashMap.put(player.getUniqueId(), new BEPlayer());
+        playerHashMap.put(player.getUniqueId(), new BEPlayer(player));
     }
 
     protected static void removePlayer(Player player) {

src/main/java/me/youhavetrouble/blockedit/optionals/SelectionHighlight.java

@@ -0,0 +1,84 @@
+package me.youhavetrouble.blockedit.optionals;
+
+import com.comphenix.protocol.PacketType;
+import com.comphenix.protocol.ProtocolLibrary;
+import com.comphenix.protocol.events.PacketContainer;
+import com.comphenix.protocol.utility.MinecraftReflection;
+import com.comphenix.protocol.wrappers.MinecraftKey;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import me.youhavetrouble.blockedit.BlockEdit;
+import org.bukkit.Location;
+import org.bukkit.entity.Player;
+
+import java.awt.*;
+import java.lang.reflect.InvocationTargetException;
+import java.nio.charset.StandardCharsets;
+
+
+/**
+ * Highlighting selection blocks thanks to https://github.com/ArtFect/BlockHighlight
+ */
+public class SelectionHighlight {
+
+    public static void highlightBlock(Player player, Location location, String color, String text, int time) {
+        if (BlockEdit.getPlugin().getServer().getPluginManager().isPluginEnabled("ProtocolLib")) {
+            sendBlockHighlight(player, location, color, text, time);
+        }
+    }
+
+    public static void sendStop(Player pl) {
+        sendPayload(pl, "debug/game_test_clear", Unpooled.wrappedBuffer(new byte[0]));
+    }
+
+    private static void sendBlockHighlight(Player player, Location location, String hex, String text, int time) {
+        ByteBuf packet = Unpooled.buffer();
+        packet.writeLong(blockPosToLong((int)location.getX(), (int)location.getY(), (int)location.getZ()));
+        int color = hex2Rgb(hex, 100).getRGB();
+        packet.writeInt(color);
+        writeString(packet, text);
+        packet.writeInt(time);
+        sendPayload(player, "debug/game_test_add_marker", packet);
+    }
+
+    private static long blockPosToLong(int x, int y, int z) {
+        return ((long) x & 67108863L) << 38 | (long) y & 4095L | ((long) z & 67108863L) << 12;
+    }
+
+    private static void writeBytes(ByteBuf packet, int i) {
+        while ((i & -128) != 0) {
+            packet.writeByte(i & 127 | 128);
+            i >>>= 7;
+        }
+        packet.writeByte(i);
+    }
+
+    private static void writeString(ByteBuf packet, String s) {
+        byte[] abyte = s.getBytes(StandardCharsets.UTF_8);
+        writeBytes(packet, abyte.length);
+        packet.writeBytes(abyte);
+    }
+
+    private static void sendPayload(Player receiver, String channel, ByteBuf bytes) {
+        PacketContainer handle = new PacketContainer(PacketType.Play.Server.CUSTOM_PAYLOAD);
+        handle.getMinecraftKeys().write(0, new MinecraftKey(channel));
+
+        Object serializer = MinecraftReflection.getPacketDataSerializer(bytes);
+        handle.getModifier().withType(ByteBuf.class).write(0, serializer);
+
+        try {
+            ProtocolLibrary.getProtocolManager().sendServerPacket(receiver, handle);
+        } catch (InvocationTargetException e) {
+            throw new RuntimeException("Unable to send the packet", e);
+        }
+    }
+
+    //https://stackoverflow.com/questions/4129666/how-to-convert-hex-to-rgb-using-java/4129692
+    private static Color hex2Rgb(String colorStr, int transparency) {
+        return new Color(
+                Integer.valueOf(colorStr.substring(1, 3), 16),
+                Integer.valueOf(colorStr.substring(3, 5), 16),
+                Integer.valueOf(colorStr.substring(5, 7), 16), transparency);
+    }
+
+}

src/main/java/me/youhavetrouble/blockedit/util/Selection.java

@@ -10,10 +10,13 @@ import java.util.UUID;
 public class Selection extends BoundingBox {
 
     private UUID worldUuid;
+    private Location selectionPoint1, selectionPoint2;
 
     public Selection(Location location1, Location location2, UUID worldUuid) {
         super(location1.getX(), location1.getY(), location1.getZ(), location2.getX(), location2.getY(), location2.getZ());
         this.worldUuid = worldUuid;
+        this.selectionPoint1 = location1;
+        this.selectionPoint2 = location2;
     }
 
     public Selection(BoundingBox boundingBox, UUID worldUuid) {
@@ -21,6 +24,14 @@ public class Selection extends BoundingBox {
         this.worldUuid = worldUuid;
     }
 
+    public Location getSelectionPoint1() {
+        return selectionPoint1;
+    }
+
+    public Location getSelectionPoint2() {
+        return selectionPoint2;
+    }
+
     public World getWorld() {
         return Bukkit.getWorld(worldUuid);
     }

src/main/resources/plugin.yml

@@ -5,6 +5,8 @@ api-version: 1.17
 authors: [ YouHaveTrouble ]
 description: Modern WorldEdit alternative
 website: youhavetrouble.me
+softdepend:
+  - ProtocolLib
 commands:
   /wand:
     permission: blockedit.wand