Jump to content

DataWatchers - saving and retrieving float values


Tomalla

Recommended Posts

Hi there. I've been recently fiddling around with Entities and DataWatchers. I've added a new entity which is a block with settable width, height and length. The entities have the first two already implemented so I had to add length field which is a float variable. I'm using DataWatcher to synch this field with the same entity on the client side.

 

I'm surprised there's no methods in DataWatcher to actually retrieve a float value! The permitted Object classes are: Byte, Short, Integer, Float, String, ItemStack and ChunkCoordinates, as listed in DataWatcher.java at the end of the file. However only methods for retrieving Byte, Short, Integer, String and ItemStack values are provided, which is ridiculous. Here's an example of such a method:

 

    public short getWatchableObjectShort(int par1)
    {
        return ((Short)this.getWatchedObject(par1).getObject()).shortValue();
    }

 

It's easy to make another method by analogy for retrieving float values, but there's one problem: DataWatcher.getWatchedObject(int) method is private - it can be accessed only from within the DataWatcher class itself.

 

Solutions? I could either use Integer for storing a float value ( i.e. value 5.3F would be stored as int value of 530, 12.56F as 1256 and so on ) - this field is not supposed no be big so it should work, however it's not a method for all of the applications obviously. Or ... modify the DataWatcher class, which I'd like to avoid doing.

 

Thoughts? Am I doing something wrong or am I missing something completely?

Link to comment
Share on other sites

it's your entity, you can modify its datawatcher's getWatchedObject flags to be public in entity constructor. but invoking method via reflection won't be cheap :/. using transformer in this case seems a bit like overkill, I'd go with that custom fixed point decimal type.

 

PS: I was wrong, invoking method via reflection is actually (after some time) same as doing it the native way :). http://stackoverflow.com/a/414823/1017211

mnn.getNativeLang() != English

If I helped you please click on the "thank you" button.

Link to comment
Share on other sites

Holy mother ... I've spent too much time programming in C++. It's like ... a sorcery of sort, changing class members accessors on the fly? I had no idea it's even possible. Java is full of surprises I see.

 

It seems it works, but I'd appreciate if you actually took a look at this code and see if there's nothing more to modify in it:

 

http://paste.minecraftforge.net/view/ed9c5d02

 

Thanks for telling me about these ... how are they called? Reflections? ;)

 

Cheers!

Link to comment
Share on other sites

yep, reflection. when I first saw that in C# I was quite stunned :D. For performance reasons I'd done setting access stuff only after datawatcher creation (in contructor of your entity?) and also the Method instance could be cached in your entity. But I might be wrong, don't have many experience with Java reflection. (But on the other hand, those changes shouldn't break anything.)

mnn.getNativeLang() != English

If I helped you please click on the "thank you" button.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



  • Recently Browsing

    • No registered users viewing this page.
  • Posts

    • Ho installato Forge 1.20.2, ho cliccato col tasto sinistro due volte su installer.jar, non si apre e crea solo un file .log Il file contiene: JVM info: Oracle Corporation - 1.8.0_401 - 25.401-b10 java.net.preferIPv4Stack=true Current Time: 27/02/2024 18:18:10 Host: files.minecraftforge.net [51.79.83.165] Host: maven.minecraftforge.net [51.79.83.165] Host: libraries.minecraft.net [13.107.213.45, 13.107.246.45] Host: launchermeta.mojang.com [13.107.246.45, 13.107.213.45] Host: piston-meta.mojang.com [13.107.246.45, 13.107.213.45] java.net.UnknownHostException: authserver.mojang.com     at java.net.Inet4AddressImpl.lookupAllHostAddr(Native Method)     at java.net.InetAddress$2.lookupAllHostAddr(Unknown Source)     at java.net.InetAddress.getAddressesFromNameService(Unknown Source)     at java.net.InetAddress.getAllByName0(Unknown Source)     at java.net.InetAddress.getAllByName(Unknown Source)     at java.net.InetAddress.getAllByName(Unknown Source)     at net.minecraftforge.installer.DownloadUtils.getIps(DownloadUtils.java:290)     at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:120) Exception in thread "main"  java.lang.NullPointerException     at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:120)
    • Suddenly the installer stopped working, both forge and neoforge, I've tested it on almost all versions of java and it didn't solve my problem.] Here is the log that appears after trying to open the file: JVM info: Oracle Corporation - 21.0.2 - 21.0.2+13-LTS-58 java.net.preferIPv4Stack=true Current Time: 27/02/2024 13:55:14 Host: maven.neoforged.net [172.67.165.187, 104.21.89.226] Host: libraries.minecraft.net [13.107.246.33, 13.107.213.33] Host: launchermeta.mojang.com [13.107.246.33, 13.107.213.33] Host: piston-meta.mojang.com [13.107.246.33, 13.107.213.33] java.net.UnknownHostException: Este host nᅢᆪo ᅢᄅ conhecido (authserver.mojang.com)     at java.base/java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)     at java.base/java.net.Inet6AddressImpl.lookupAllHostAddr(Inet6AddressImpl.java:52)     at java.base/java.net.InetAddress$PlatformResolver.lookupByName(InetAddress.java:1211)     at java.base/java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1828)     at java.base/java.net.InetAddress$NameServiceAddresses.get(InetAddress.java:1139)     at java.base/java.net.InetAddress.getAllByName0(InetAddress.java:1818)     at java.base/java.net.InetAddress.getAllByName(InetAddress.java:1688)     at net.minecraftforge.installer.DownloadUtils.getIps(DownloadUtils.java:296)     at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:124) Exception in thread "main" java.lang.NullPointerException: Cannot invoke "java.util.List.stream()" because the return value of "net.minecraftforge.installer.DownloadUtils.getIps(String)" is null     at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:124)   If anyone knows how to solve this please tell me.
  • Topics

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.