Flux multi-user server

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Definition

Flux multi-user server (alis Hydra) is Open Virtual Worlds Web Server made by Media Machines. Currently in alpha/early beta - 18:22, 6 July 2007 (MEST)

Installation

Daniel K. Schneider on his personal Linux Desktop (Ubuntu 6.10). Disclaimer: I am not a programmer nor a sysadmin. Also, I use root to do command-line installations (can't get myself to type sudo in repetition).

Downlods

  1. Get the Hawk Network Library version 1.7 by Phil Frisbie (LGPL). You can find it in the downloads section.
  2. Get Hydra, Flux Multi-User
  3. Get MySQL development libraries
  4. Also install Flux Player 2.1 if you don't have it already.

Preparation of installation

MySQL
  • Install MySQL and the development libararies !
  • Use Synaptic Package Manger or apt-get and install these

I took:

mysql-server
libmysqlclient15-dev

If don't want to type command-lines to mysql, you also may want to install a mysql administration client. I tried (but then only used it to change the root password of the mysql server).

mysqladmin

This tool then will show up under Applications/Systems tools. First time you connect you can use 'root' without password.

Then, open a terminal and become root:

su
Hydras (files)

Currently (July 2007) you have to compile Hydras and HawkNL it yourself.

  • unzip into a folder, e.g. I used
/usr/local/flux/hydra
Modify some source code
  • I suggest to make a change to scenemodel.c (else you will have to use database, user and password for MySQL... Change line 51 from:
(&hydra_db, "localhost", "user", "password", "database", 0, NULL, 0) != NULL);

to:

 (&hydra_db, "localhost", "hydrausr", "SECRET", "hydra", 0, NULL, 0) != NULL);
  • Edit hydras.c, i.e. replace
char *url = "http://worlds.webers.org/content/testbed/";

by something of your own

HawkNL
  • Put it in a folder named "HawkNL" at the same level as the folder containing the Hydra sources. E.g. I used
/usr/local/flux/HawkNL
 unzip HawkNL17b1src.zip [-d "flux directory"]
 cd "flux directory"
 ln -s HawkNL1.70 HawkNL
Result is something like this
/usr/local/flux
lrwxrwxrwx  1 root root   10 2007-07-06 15:28 HawkNL -> HawkNL1.70
drwxr-xr-x  7 root root 4096 2007-07-06 15:27 HawkNL1.70
drwxr-xr-x  2 root root 4096 2007-07-06 15:40 hydra
drwxr-xr-x  2 root root 4096 2007-07-06 15:39 src

Compilation

HawNL
 cd HawkNL
 make -f makefile.linux
 make -f makefile.linux install

It will also copy the libraries in /usr/local/lib and header to /usr/local/include/nl.h

Hydras
  • On Windows, load the hydras.sln or hydrac.sln solution files into MSVC 2003 or later (not tested)
  • On Linux (I used Ubuntu) run make on the Makefile with gcc installed.
cd hydra
make

Result:

gcc -I/usr/include/mysql -DUSE_MYSQL -c scenemodel.c
gcc -I/usr/include/mysql -DUSE_MYSQL -c netcontroller.c
gcc -c netview.c
gcc -c -ggdb swamp.c
gcc -o hydras -pthread hydras.o clients.o scenemodel.o netcontroller.o  netview.o swamp.o ../HawkNL/src/libNL.a -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
gcc -c -ggdb hydrac.c
gcc -o hydrac -pthread hydrac.o swamp.o ../HawkNL/src/libNL.a
hydrac.o: In function `printErrorExit':
/usr/local/flux/hydra/hydrac.c:76: warning: the `gets' function is dangerous and should not be used.
make: *** No rule to make target `hydrabot', needed by `all'.  Stop.

This doesn't seem to be harmful (for the moment) since hydras (the server) is built.

MySQL database

Create a hydra database and a user (same as in scenemodel.c)

I used the command line since I couldn't figure out how to use the GUI ;)

mysql -p
  • You have to create a hydra_db databse called hydra
mysql> create database hydra;
  • Then create the user called hydrausr (change secret of course)
mysql> create user hydrausr identified by 'secret';
  • Then give it rights to the hydra database
mysql > GRANT SELECT,INSERT,UPDATE,DELETE,CREATE,DROP ON hydra.* TO 'hydrausr'@'localhost';
  • Then reload the privileges
mysql > flush privileges;
Create a User table

Run it to test if it may work

Type: hypdras

./hydras

You may see:

port is 13214
url is http://worlds.webers.org/content/testbed/
connected to database

From another terminal, type:

./hydrac

You may see:

read 4 bytes, messlen is 6
read 6 bytes, messlen is 6
hello yourid=0, mytoken=NA

... and messages if people connect

Make a shared scene

To test, get the Flux Multi-user test files from media machines and dezip on some webserver.

Then edit files localplane.x3d and testbed.x3d etc. and change from:

 url="'swmp://localhost:13214/MM-6-12345678'"/>

to the URL of your Hydra server (not the webserver !)


Links

Mediamachines


Help for installation