Project

General

Profile

Wiki » History » Version 29

Josip Almasi, 10/15/2021 03:03 PM

1 4 Josip Almasi
{{toc}}
2
3 1 Josip Almasi
h1. Welcome!
4 2 Josip Almasi
5 18 Josip Almasi
h2. External resources
6 4 Josip Almasi
7 14 Josip Almasi
Demo site: https://www.vrspace.org/
8
9 15 Josip Almasi
Github project page: https://github.com/jalmasi/vrspace
10 2 Josip Almasi
11 16 Josip Almasi
OpenSource.com article (motivation): https://opensource.com/article/20/12/virtual-reality-server
12 3 Josip Almasi
13 15 Josip Almasi
VR Days video (features, technologies): https://vimeo.com/475142708
14 3 Josip Almasi
15 15 Josip Almasi
Youtube channel: https://www.youtube.com/channel/UCLdSg22i9MZ3u7ityj_PBxw
16 1 Josip Almasi
17 16 Josip Almasi
Facebook page: https://fb.com/vrspace.org
18 14 Josip Almasi
19
Client API jsdoc: https://www.vrspace.org/docs/jsdoc/index.html
20
21
Server javadoc: https://www.vrspace.org/docs/javadoc/index.html?overview-summary.html
22 4 Josip Almasi
23 23 Josip Almasi
h2. Playgrounds
24
25
Multi-user interaction, shared objects: https://playground.babylonjs.com/#ZBK155
26
Multi-user world: https://playground.babylonjs.com/#Y6ILJ5
27
Avatar selection, portals: https://playground.babylonjs.com/#HDV7LA
28 24 Josip Almasi
VR Avatar template world: https://www.babylonjs-playground.com/#VXA0R3
29 23 Josip Almasi
30 17 Josip Almasi
h1. Frequently Asked Questions
31
32
h2. Is this open source, free to use and share?
33
34
Yes, it's all free and open. Server and client code is published under Apache 2 license, all 3D models published by their respective authors under Creative Commons Attribution license.
35
36
h2. Is there any documentation?
37
38
This is good place to start, this page links to all available resources.
39
40
h2. How many users can share a “world/space” simultaneously?
41
42
By default, number of users per space is not limited. There is a server parameter to limit that (org.vrspace.server.maxSessions) that can be specified either in config file or command line. Users that hit the limit remain in the queue for configurable timeout (org.vrspace.server.sessionStartTimeout, zero by default) until someone leaves. An error is raised on timeout.
43
44 4 Josip Almasi
h1. Setting up development environment
45
46
Here's all you need to start development on Windows.
47 20 Josip Almasi
Linux distributions include all these tools as native packages, so no additional downloads should be required.
48 4 Josip Almasi
49
h2. Basic setup
50
51
h3. Git bash
52
53
IDEs can work with github directly, but whatever you ask, you'll get a command line answer.
54
Command line git is simply a must have. Bash also includes a lot of goodies like ssh.
55
56
https://git-scm.com/downloads
57
58
h3. Java
59
60 21 Josip Almasi
Java 8 will work, java 11 recommended. JDK is required to build the server.
61
Get it either from Oracle or elsewhere, e.g. Zulu OpenJDK: https://www.azul.com/downloads/zulu-community/?package=jdk
62 4 Josip Almasi
63
h3. Node.js
64
65
Node is used by IDE to evaluate javascript. You'll also may need it if you modify any of babylon.js source.
66
Mind that IDE will complain if you installed unsupported version of Node; should that happen, remove Node, and install latest one supported.
67
68
Get it from https://nodejs.org/
69
70 19 Josip Almasi
h3. Maven
71
72
Apache Maven is used to build the server from command prompt.
73
74
Get it from https://maven.apache.org/download.cgi
75
76
77 4 Josip Almasi
h3. IDE
78
79
Eclipse for Java developers (not enterprise), with Spring and Web plugins:
80
81
Download eclipse here: https://www.eclipse.org/
82
83
And then go to Help -> Eclipse Marketplace
84
Search and install Spring Tools 4 and Wild Web Developer plugins.
85
86 6 Josip Almasi
You'll also need to download and install https://projectlombok.org/
87 8 Josip Almasi
Once done, restart the eclipse.
88 6 Josip Almasi
89 5 Josip Almasi
h2. Import and start the project
90
91 22 Josip Almasi
h3. IDE
92
93 5 Josip Almasi
In Eclipse, you can use either default or new workspace for the project.
94
Assuming you have cloned the project from the github, 
95
Go to File -> Open Projects From the Filesystem
96
Then choose vrspace directory.
97
98
This will import vrspace folders and project subfolders, click Finish.
99
100
In vrspace project folder, in src/main/java, there's org.vrspace.server.ServerApplication.java.
101
Open it, then right click on the code.
102
From the menu, choose either Run as or Debug as -> Spring Boot App.
103
104
Open http://localhost:8080/babylon/connect.html with two browsers, and navigate around.
105
106
That's all, you're all set!
107 22 Josip Almasi
108
h3. git bash
109
110
git clone https://github.com/jalmasi/vrspace.git
111
cd vrspace
112
mvn clean install
113
java -jar server/target/server-0.2.2.jar
114 4 Josip Almasi
115
h2. Advanced setup
116
117 12 Josip Almasi
h3. SSL
118 4 Josip Almasi
119 12 Josip Almasi
HTTPS is required for pretty much everything - WebXR, camera, mic access.
120
By default, the server runs on 8080 port with plain HTTP. To enable HTTPS, edit application.properties (found in src/main/resources), and change following properties:
121 1 Josip Almasi
122 12 Josip Almasi
<pre>
123
server.ssl.enabled=false
124
# default port 8080
125
#server.port=8443
126 13 Josip Almasi
</pre>
127 12 Josip Almasi
128
h3. Apache
129
130
Apache reverse proxy setup, linux, windows, TBD
131 4 Josip Almasi
132
h3. Docker and OpenVidu
133
134
OpenVidu voice/video chat server runs as docker image. This is only required for development of voice chat functions.
135
136 10 Josip Almasi
Local execution (development):
137 11 Josip Almasi
docker run -p 4443:4443 --rm -e OPENVIDU_SECRET=YOUR_SECRET -e DOMAIN_OR_PUBLIC_IP=YOUR_IP openvidu/openvidu-server-kms:2.17.0
138 10 Josip Almasi
139
Running on server:
140 1 Josip Almasi
https://docs.openvidu.io/en/2.17.0/deployment/deploying-on-premises/
141 11 Josip Almasi
142
Then either modify openvidu.publicurl and openvidu.secret in application.properties, or run server.jar with -Dopenvidu.publicurl=YOUR_URL and -Dopenvidu.secret=YOUR_SECRET
143 25 Josip Almasi
144
h1. Software Architecture
145 26 Josip Almasi
146
!https://redmine.vrspace.org/attachments/download/15/vrspace-diagram.png!
147
148
h2. Client-Server Communication
149
150
Clients communicate with server over "WebSockets":https://en.wikipedia.org/wiki/WebSocket. Reference javascript implementation of client communication layer is in "VRSpace.js":https://www.vrspace.org/docs/jsdoc/VRSpace.html.
151
152
General approach to communication is rather obscure Half-Object pattern: server-side and client-side object have same properties, but different implementations.
153
Whenever an object's property changes in (any) client's address space, it's transmitted to the server, that broadcasts it to all clients currently 'watching' the object.
154
155
Whenever a client wants to perform any change to any object in the space, it has to go through the VRSpace server.
156
Clients may or may not communicate directly, but this is out of the scope of VRSpace server.
157
158
h2. Server Responsibilities
159
160
Sole responsibility of VRSpace server is management of 3D space: persisting space objects, tracking their properties, processing and distributing events from/to objects.
161 27 Josip Almasi
Whenever we talk about objects, that includes clients, i.e. users - a client is a special case of an object.
162
The server does not even handle the authentication - it is assumed to be responsibility of web app serving the space.
163
3D geometry is also not in server's scope, it's just another property of an object (mesh).
164
165
h2. Server design
166
167
Key concepts here are Active Objects, Actor model, and Live distributed object.
168
169
"VRObject":https://github.com/jalmasi/vrspace/blob/master/server/src/main/java/org/vrspace/server/obj/VRObject.java is a basic shared object, with some basic properties like position and rotation, and of course, mesh. It essentially a "Live distributed object":https://en.wikipedia.org/wiki/Live_distributed_object.
170
171 28 Josip Almasi
"Client":https://github.com/jalmasi/vrspace/blob/master/server/src/main/java/org/vrspace/server/obj/Client.java extends VRObject, and adds capabilities to communicate over web sockets, and listen to changes to other objects. Typically, a client represents a remote user, but it can also represent a robot connected over a web socket, or be a base class for a server-side robot.
172
A Client can be thought of as "Active Object":https://en.wikipedia.org/wiki/Active_object or an "Actor":https://en.wikipedia.org/wiki/Actor_model, 
173 27 Josip Almasi
174
Server relies on Spring Boot and embedded Tomcat to handle all I/O and threads.
175 29 Josip Almasi
176
h2. Client
177
178
Each "Client":https://github.com/jalmasi/vrspace/blob/master/server/src/main/java/org/vrspace/server/obj/Client.java has it's own "Scene":https://github.com/jalmasi/vrspace/blob/master/server/src/main/java/org/vrspace/server/core/Scene.java that tracks all shared objects - including other clients - visible by the client. The scene is initially populated once the client logs in to the server, and starts the session. Scene is refreshed periodically, or after specified resolution.
179
180
Scene maintains the event model, by adding the Client as listener to all other active objects (usually other users) in the scene.
181
182
Client simply notifies it's listeners on any changes to any of it's own properties. Any changes on observed objects are sent over the network to the user's web client.