Nameplates With No (Visible) Mob Underneath (Holograms)

Spent yesterday working on some code for this. I got a quick implementation going using ProtocolLib and PacketWrapper.

THIS IS WORKING IN 1.7
I don't know why people think it broke. I'm not using any nms. The libraries I use work in most versions of minecraft will most likely already work in 1.8. (As long as they don't add any major protocol chages.)

Here is the code for a Nametag object.

Code:

import com.comphenix.packetwrapper.WrapperPlayServerAttachEntity;
import com.comphenix.packetwrapper.WrapperPlayServerEntityDestroy;
import com.comphenix.packetwrapper.WrapperPlayServerEntityMetadata;
import com.comphenix.packetwrapper.WrapperPlayServerEntityTeleport;
import com.comphenix.packetwrapper.WrapperPlayServerSpawnEntity;
import com.comphenix.packetwrapper.WrapperPlayServerSpawnEntityLiving;
import com.comphenix.protocol.ProtocolLibrary;
import com.comphenix.protocol.wrappers.WrappedDataWatcher;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import org.bukkit.Location;
import org.bukkit.entity.EntityType;
import org.bukkit.entity.Player;
 
/**
*
* @author gyroninja
*/
public class Nametag {
 
    int id;
 
    Location loc;
 
    double dy;
 
    String name;
 
    public Nametag(int id, Location loc, double dy, String name) {
 
        this.id = id;
 
        this.loc = loc;
 
        this.dy = dy;
 
        this.name = name;
    }
 
    public void showNametag(Player p) throws InvocationTargetException {
 
        WrapperPlayServerSpawnEntityLiving horse = new WrapperPlayServerSpawnEntityLiving();
 
        horse.setEntityID(id);
 
        horse.setType(EntityType.HORSE);
 
        horse.setX(loc.getX());
        horse.setY(loc.getY() + dy + 55);
        horse.setZ(loc.getZ());
 
        WrappedDataWatcher wdw = new WrappedDataWatcher();
 
        wdw.setObject(10, name);
        wdw.setObject(11, (byte) 1);
 
        wdw.setObject(12, -1700000);
 
        horse.setMetadata(wdw);
 
        ProtocolLibrary.getProtocolManager().sendServerPacket(p, horse.getHandle());
 
        WrapperPlayServerSpawnEntity skull = new WrapperPlayServerSpawnEntity();
 
        skull.setEntityID(id + 1);
 
        skull.setType(66);
 
        skull.setX(loc.getX());
        skull.setY(loc.getY() + dy + 55);
        skull.setZ(loc.getZ());
 
        ProtocolLibrary.getProtocolManager().sendServerPacket(p, skull.getHandle());
 
        WrapperPlayServerAttachEntity attach = new WrapperPlayServerAttachEntity();
 
        attach.setEntityId(id);
        attach.setVehicleId(id + 1);
 
        ProtocolLibrary.getProtocolManager().sendServerPacket(p, attach.getHandle());
    }
 
    public void hideNametag(Player p) throws InvocationTargetException {
 
        WrapperPlayServerEntityDestroy destroy = new WrapperPlayServerEntityDestroy();
 
        ArrayList<Integer> entities = new ArrayList<>();
 
        entities.add(id);
        entities.add(id + 1);
 
        destroy.setEntities(entities);
 
        ProtocolLibrary.getProtocolManager().sendServerPacket(p, destroy.getHandle());
    }
 
    public void setLocation(Player p, Location loc) throws InvocationTargetException {
 
        WrapperPlayServerEntityTeleport teleport = new WrapperPlayServerEntityTeleport();
 
        teleport.setEntityID(id + 1);
 
        teleport.setX(loc.getX());
        teleport.setY(loc.getY() + 55 + dy);
        teleport.setZ(loc.getZ());
 
        ProtocolLibrary.getProtocolManager().sendServerPacket(p, teleport.getHandle());
    }
 
    public void setName(Player p, String name) throws InvocationTargetException {
 
        this.name = name;
 
        WrapperPlayServerEntityMetadata eMeta = new WrapperPlayServerEntityMetadata();
 
        eMeta.setEntityId(id);
 
        WrappedDataWatcher wdw = new WrappedDataWatcher();
 
        wdw.setObject(10, name);
 
        eMeta.setEntityMetadata(wdw.getWatchableObjects());
 
        ProtocolLibrary.getProtocolManager().sendServerPacket(p, eMeta.getHandle());
    }
}

That is used for having a single nametag entity.

For a list of multiple Nametags you can use NametagList

Code:

import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import org.bukkit.Location;
import org.bukkit.entity.Player;
 
/**
*
* @author gyroninja
*/
public class NametagList {
 
    ArrayList<Nametag> nametags = new ArrayList<>();
 
    public ArrayList<Nametag> getNametags() {
 
        return nametags;
    }
 
    public void showNametags(Player p) throws InvocationTargetException {
 
        for (Nametag nametag : nametags) {
 
            nametag.showNametag(p);
        }
    }
 
    public void hideNametags(Player p) throws InvocationTargetException {
 
        for (Nametag nametag : nametags) {
 
            nametag.hideNametag(p);
        }
    }
 
    public void setLocation(Player p, Location loc) throws InvocationTargetException {
 
        for (Nametag nametag : nametags) {
 
            nametag.setLocation(p, loc);
        }
    }
}

To add nametags to a list just call getNametags() and add a Nametag object to them.
Class for loading pictures to nametags. Note this probably isn't the most optimal code. (GroupNametag extends JavaPlugin it can be any plugin)

Code:

import java.awt.AlphaComposite;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.net.URL;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.Color;
import org.bukkit.Location;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;
 
/**
*
* @author gyroninja
*/
public class NametagUtils {
 
    private static GroupNametag gnt;
 
    int currentID = 9000;
 
    Color[] colors = {
 
        Color.fromRGB(0, 0, 0),
        Color.fromRGB(0, 0, 170),
        Color.fromRGB(0, 170, 0),
        Color.fromRGB(0, 170, 170),
        Color.fromRGB(170, 0, 0),
        Color.fromRGB(170, 0, 170),
        Color.fromRGB(255, 170, 0),
        Color.fromRGB(170, 170, 170),
        Color.fromRGB(85, 85, 85),
        Color.fromRGB(85, 85, 255),
        Color.fromRGB(85, 255, 85),
        Color.fromRGB(85, 255, 255),
        Color.fromRGB(255, 85, 85),
        Color.fromRGB(255, 85, 255),
        Color.fromRGB(255, 255, 85),
        Color.fromRGB(255, 255, 255)
    };
 
    public void loadImage(String url) {
 
        ArrayList<String> lines = new ArrayList<>();
 
        if (url.endsWith(".gif")) {
 
            try {
 
                ImageReader reader = (ImageReader)ImageIO.getImageReadersByFormatName("gif").next();
               
                reader.setInput(ImageIO.createImageInputStream(new URL(url).openStream()), false);
 
                int frames = reader.getNumImages(true);
 
                ArrayList<NametagList> tags = new ArrayList<>();
 
                for (int i = 0; i < frames; i++) {
 
                    lines = getLinesFromImage(reader.read(i));
 
                    NametagList nametagList = new NametagList();
 
                    for (int i2 = 0; i2 < lines.size(); i2++) {
 
                        String line = lines.get(i2);
 
                        nametagList.nametags.add(new Nametag(currentID, new Location(Bukkit.getWorlds().get(0), 0, 80, 0), 20 - (i2 * 0.25), line));
 
                        currentID += 2;
                    }
 
                    tags.add(nametagList);
 
                    if (i == 0) {
 
                        try {
 
                            for (Player p : Bukkit.getOnlinePlayers()) {
 
                                nametagList.showNametags(p);
                            }
                        }
 
                        catch (InvocationTargetException ex) {
 
                            Logger.getLogger(GroupNametag.class.getName()).log(Level.SEVERE, null, ex);
                        }
                    }
                }
 
                Bukkit.getScheduler().scheduleSyncDelayedTask(this, new UpdateNametagTask(10, tags));
            }
 
            catch (IOException ex) {
 
                Logger.getLogger(GroupNametag.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
 
        else {
 
            try {
 
                lines = getLinesFromImage(ImageIO.read(new URL(url)));
            }
 
            catch (IOException ex) {
 
                Logger.getLogger(GroupNametag.class.getName()).log(Level.SEVERE, null, ex);
            }
 
            NametagList nametagList = new NametagList();
 
            for (int i = 0; i < lines.size(); i++) {
 
                String line = lines.get(i);
 
                nametagList.nametags.add(new Nametag(currentID, new Location(Bukkit.getWorlds().get(0), 0, 80, 0), 20 - (i * 0.25), line));
 
                currentID += 2;
            }
 
            try {
 
                for (Player p : Bukkit.getOnlinePlayers()) {
 
                    nametagList.showNametags(p);
                }
            }
 
            catch (InvocationTargetException ex) {
 
                Logger.getLogger(GroupNametag.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }
 
    public double getDistance(Color c1, Color c2) {
 
        double rmean = (c1.getRed() + c2.getRed()) / 2.0;
 
        double r = c1.getRed() - c2.getRed();
        double g = c1.getGreen() - c2.getGreen();
        int b = c1.getBlue() - c2.getBlue();
 
        double weightR = 2 + rmean / 256.0;
        double weightG = 4.0;
        double weightB = 2 + (255 - rmean) / 256.0;
 
        return weightR * r * r + weightG * g * g + weightB * b * b;
    }
 
    public ArrayList<String> getLinesFromImage(BufferedImage image) {
 
        ArrayList<String> lines = new ArrayList<>();
 
        if (image.getWidth() > 128) {
 
            BufferedImage tmp = new BufferedImage(128, image.getHeight() / (image.getWidth() / 128), BufferedImage.TYPE_INT_ARGB);
 
            Graphics2D resizer = tmp.createGraphics();
 
            resizer.setComposite(AlphaComposite.Src);
 
            resizer.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
            resizer.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
            resizer.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
 
            resizer.drawImage(image, 0, 0, 128, image.getHeight() / (image.getWidth() / 128), null);
 
            resizer.dispose();
 
            image = tmp;
        }
 
        int width = image.getWidth();
        int height = image.getHeight();
 
        for (int y = 0; y < height; y++) {
 
            StringBuilder line = new StringBuilder();
 
            for (int x = 0; x < width; x++) {
 
                int color = image.getRGB(x, y);
 
                int red = (color & 0x00ff0000) >> 16;
                int green = (color & 0x0000ff00) >> 8;
                int blue = color & 0x000000ff;
 
                int alpha = (color>>24) & 0xff;
 
                if (alpha < 128) {
 
                    line.append(ChatColor.WHITE);
                    line.append("⬛");
 
                    continue;
                }
 
                int index = 0;
                int best = -1;
 
                for (int i = 0; i < colors.length; i++) {
 
                    double distance = getDistance(Color.fromRGB(red, green, blue), colors[i]);
 
                    if (x == 0 && y == 0) {
 
                        Bukkit.broadcastMessage(colors[i].toString());
                    }
 
                    if (distance < best || best == -1) {
 
                        best = (int) distance;
 
                        index = i;
                    }
                }
 
                line.append(ChatColor.values()[index]);
                line.append("⬛");
            }
 
            lines.add(line.toString());
        }
 
        return lines;
    }
}

And for making the gifs animated

Code:

import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.bukkit.Bukkit;
import org.bukkit.entity.Player;
import org.bukkit.scheduler.BukkitRunnable;
 
/**
*
* @author gyroninja
*/
public class UpdateNametagTask extends BukkitRunnable {
 
    int frame = 0;
    int next = 1;
 
    int delay;
 
    ArrayList<NametagList> tags;
 
    public UpdateNametagTask(int delay, ArrayList<NametagList> tags) {
 
        this.delay = delay;
 
        this.tags = tags;
    }
 
    @Override
    public void run() {
 
        try {
 
            for (int i = 0; i < tags.get(frame).nametags.size(); i++) {
 
                Nametag nametag = tags.get(frame).nametags.get(i);
                Nametag nametag2 = tags.get(next).nametags.get(i);
 
                for (Player p : Bukkit.getOnlinePlayers()) {
 
                    //nametag.setName(p, nametag2.name); Meh doesn't work, not exactly sure why.
                    nametag.hideNametag(p);
                    nametag2.showNametag(p);
                }
            }
 
            frame++;
            next++;
 
            if (frame == tags.size()) {
 
                frame = 0;
            }
 
            if (next == tags.size()) {
 
                next = 0;
            }
 
            if (next != 0) {
 
                Bukkit.getScheduler().scheduleSyncDelayedTask(GroupNametag.getInstance(), this, delay);
            }
        }
 
        catch (InvocationTargetException ex) {
 
            Logger.getLogger(UpdateNametagTask.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

Here's an example of what's possible with these.



Edit: Forgot to link to Asdjke's video on this, was in a rush. This version is a bit different and just uses packets to add them.

Edit2: Upgraded my code to the new PacketWrapper source https://github.com/aadnk/PacketWrapper
Edit 3: Updated a lot of the code

 

You should give credit to the guy who came up with it as well.

Nice work, though

 

gyroninja This does not work with current versions of CraftBukkit as Packet names have been changed.

Packet18SpawnMob is now PacketPlayOutSpawnEntity (I believe, please correct me if im wrong)

 

If nobody else does I'll probably make something to convert images/text nicely in the next week.

 

I'm using PacketWrapper (https://github.com/aadnk/PacketWrapper)
This will work in current versions. I didn't want to dabble with NMS too much with this project
and this is a cleaner solution.

 

Do the nameplates move with the player, or do they remain stationary?

 

1. Is it posible to attach it to player?
2. Could someone update it to 1.7?
3. Could someone tell my how to make it independence to ProtocolLib?

 

1. Not really, I guess you could teleport it.
2. I'll make a..."cleaner" version later when I get some certain stuff done.
3. ^

 

Garris0n Would be great if you could find way to attach it to player. I have awesome idea for this.

 

In theory you could.

 

Am currently trying to update it to 1.7 NMS.... but im not very good with NMS...

My current progress is at https://gist.github.com/Goblom/9137084

Please note, i'm not very good good with NMS and i haven't played with it much. The basis of the Hologram system is there, but there is no way to set the location or the message because i haven't gotten that far into it before pulling some hair out trying to understand the EntityHorse NMS class...

I Might go back and complete the class in the future but for now, others can use it as a base for which they need to finish (If they wish)

 

https://github.com/Bukkit/CraftBukk...t/minecraft/server/EntityInsentient.java#L745
https://github.com/Bukkit/CraftBukk...t/minecraft/server/EntityInsentient.java#L757

Or you could use .getBukkitEntity.

 

Garris0n That is using CraftBukkit Classes... Since i know how to use those i didn't want to use them. I want experience with NMS as it interests me and is (not necessarily) a good thing to learn, but its fun to learn and use. Especially when using reflection, because you could could essentially have more control over entity manipulation.

If you feel that using a CraftBukkit Class is more efficient then by all means go for it.

Edit: I was wrong, I missed the package of the classes Garris0n posted

 

Wait what? What exactly are you using then?

 

Garris0n Its using NMS (Net Minecraft Server) calling classes from net.minecraft.server.[version].[class]

Using EntityInsentient is using OBC, i think that is what its called, (Org Bukkit CraftBukkit) calling classes from org.bukkit.craftbukkit.[version].[class]

Edit: EntityInsentiant is not OBC, its NMS, i missed the package for the class.

 

timtower Welcome to it. I might not complete the version i posted as everyone i have talked to recommended using CraftBukkit classes, and i do not want to do that. So, i got stuck, and started pulling hair out...

If you get stuck trying to read my code, well, you have my skype and are welcome to ask questions

 

EntityInsentient is NMS, CraftLivingEntity would be the OBC class.

Essentially it's structured in three "sets":
The interfaces from the Bukkit API (Pig) - These are just interfaces to be used as the API dependency, they generally do not contain any actual code.
The OBC classes from CraftBukkit (CraftPig) - These implement the interfaces and are what the entities "truly" are. They only have one practical use for a developer: getting the...
NMS classes (EntityPig) - These contain the actual source of the entity, while the OBC class is a kind of "bridge" between the NMS and the API. They also contain plenty of obfuscated methods and other fun stuff.

 

Garris0n Woops, i missed the Package name ... But at least i got some of my information right I was kind of iffy with my description.

Edit: Get corrected, and also learned something new. Awesome

 

Also, just for the record, whenever I do make it my version won't be using reflection. Using raw NMS is more efficient, and the package names were added for good reason and shouldn't be "hacked" around.

 

Garris0n (if I understand correctly) By using raw NMS you mean importing nms classes...

The only reason i opped for reflection is because the names will be the same through mc versions (no need to fix imports for every bukkit update). So, i wont need to import NMS classes for the specific version of MC that i want to use...

Importing NMS classes that are specific to the version of mc is not that efficient because the imports will have to be changed every update and also not be compatible through bukkit updates.

 

The point is that you have to change them so you actually look through your code and fix any issues. And reflection is just not efficient in general, it's much slower than importing the NMS classes and using them.

Also, opted.

 

Well I have no Idea wtf anyones talking about here..........

 

Onlineids Discussion turned argument turned debate turned discussion, between Garris0n and I

 

To?

Goblom is working on it.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Garris0n Bart

I have decided to not stop working on a port for 1.7. I will be working with timtower to port this over to 1.7 and above.

We are going to turn our work into a plugin and post it on bukkit dev. Project has already been created, but main page looks like crap (I need someone to help out with making it look all pretty) (Click me to go to DBO Project Page)

 

Well then, uh, me later Bart.

 

so no worky in 1.7.x then? and if not, how do i implement it? cheers

 

TeamJesus Use Bukkit version pre-1.7 until someone ports a separate class, or the Holographic plugin is completed

 

how can i do this? This looks so awesome. I want to implement this on my network. Is someone updating it?