X3DV: Difference between revisions

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See also:  
See also:  
* Our list of [[X3D tutorials]] (started in oct 2010, .... better versions may be available by the end of 2011)
* Our list of [[X3D tutorials]] (started in oct 2010, .... better versions may be available by the end of 2011)
* [[web 3D technology]] (short overview), [[VRML]] (precursor of X3D), [[3D interactive environment]], [[3D modeling]], [[Collada]] (a similar format) and [[WebGL]] (a new low-level 3D  graphics API for web browsers)
* [[X3DOM]] which is X3D within [[HTML5]]
* [[web 3D technology]] (short overview), [[3D Tour]], [[VRML]] (precursor of X3D), [[3D interactive environment]], [[3D modeling]], [[Collada]] (a similar format) and [[WebGL]] (a new low-level 3D  graphics API for web browsers)


== How to build X3D scenes, a very short overview ==
== How to build X3D scenes, a very short overview ==

Revision as of 09:04, 31 March 2011

Draft

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Definition

X3D is a Web 3D technology.

“X3D is a royalty-free open standards file format and run-time architecture to represent and communicate 3D scenes and objects using XML. It is an ISO ratified standard that provides a system for the storage, retrieval and playback of real time graphics content embedded in applications, all within an open architecture to support a wide array of domains and user scenarios.
X3D has a rich set of componentized features that can tailored for use in engineering and scientific visualization, CAD and architecture, medical visualization, training and simulation, multimedia, entertainment, education, and more.
The development of real-time communication of 3D data across all applications and network applications has evolved from its beginnings as the Virtual Reality Modeling Language (VRML) to the considerably more mature and refined X3D standard.”
(web|3D, retrieved 12:59, 11 March 2009 (UTC)).

“X3D focuses on the visualization of 3D assets within applications. X3D has principally been targeted for the Web (thus the name and focus of the Web3D Consortium). X3D is a delivery format intended to contain the information needed for interactive applications. X3D specifies behaviors and interaction, and it includes both a specific run-time model that enables picking, viewing, navigation, and scripting, and an API to manipulate the scene graph at run-time.” (Arnaud and Parisi, 2007).

See also:

How to build X3D scenes, a very short overview

X3D scenes can contain two sorts of "contents": Objects and behaviors.

Creating objects

Basically, there are three kinds of options for creating a 3D object:

  • Build 3D scenes or elements of the scene with a tool that can export to X3D, i.e. a 3D modeling tool or a 3D Computer-aided_design_and_manufacturing#Software CAD tool.
  • Use a special-purpose X3D editor. Often such editors can import models formats produced with other 3D software (previous option) or this other software can export to X3D. Therefore, X3D editors are often just to used to assemble a scene and to make it interactive with behaviors.
  • Use an XML editor

Here is a longer list of options (John F. Richardson / VRML mailing list):

  1. An open source modeling and animation system like Blender or Wings3D
  2. A commercial modeling and animation system like Maya or Lightwave3D or Softimage
  3. Your own proprietary modeling and animation system
  4. Free for personal use commercial VRML/X3D authoring tool like Vivaty
  5. Commercial VRML/X3D authoring system [ authoring systems from Vivaty / Octaga / Bitmanagement / Parallel Graphics / … ]. Cost varies.
  6. Open source VRML/X3D authoring system like X3D-Edit.
  7. A text editor, preferably an schema-aware XML editor
  8. A text editor without any XML support

See below and also the Web3D website for lists of tools

Creating behaviors

A so-called behavior can be defined as changing the value of property of an object with the scene. Values are usually numbers, e.g. define the size or shape or position of an object.

Behaviors can be triggered by various means such as "data producers" (e.g. a user navigates close to an object), interpolations (computer generated values over time) or scripts. These data producers are connected to objects that they change through ROUTEs. More specifically a ROUTE passes an event, i.e. a value change at a given time from an "output" field of an object to an "input" field of another object.

The scene graph

According to Nicholas f. Polys (retrieved Aug 27 2010), “Conceptually, each X3D application is a 3D time-based space that contains graphic and aural objects that can be loaded over a network and dynamically modified through a variety of mechanisms. The semantics of X3D describe an abstract functional behaviour of time-based, interactive 3D, multimedia information.
The basic unit of the X3D run-time environment is the scene graph. This structure contains all the objects in the system and their relationships. Relationships are contained along several axes of the scene graph. The transformation hierarchy describes the spatial relationship of rendering objects. The behavior graph describes the connections between fields and the flow of events through the system. An X3D scene graph is a directed acyclic graph. Nodes can contain specific fields with one or more children nodes which participate in the hierarchy. These may, in turn, contain nodes (or instances of nodes). This hierarchy of nodes is called the scene graph. Each arc in the graph from A to B means that node A has a field whose value directly contains node B.”

X3D, a modular architecture

Unlike its VRML predecessor, X3D has a modular architecture with four baseline profiles (What is X3D?

  • Interchange is the basic profile for communicating between applications. It support geometry, texturing, basic lighting, and animation
  • Interactive enables basic interaction with a 3D environment by adding various sensor nodes for user navigation and interaction (e.g., PlanseSensor, TouchSensor, etc.), enhanced timing, and additional lighting (Spotlight, PointLight).
  • Immersive enables full 3D graphics and interaction, including audio support, collision, fog, and scripting.
  • Full includes all defined nodes including NURBS, H-Anim (animated interactive Avatars) and GeoSpatial components.
X3D Baseline Profiles: Source: What is X3D?, retrieved 11:53, 26 August 2010 (UTC)

Software

X3D Clients

There exist several clients for Win/Linux/Mac. The best ones are probably commercial (in particular BS Contact), they provide free versions that include some "nagging", i.e. a crawling logo.

To check what X3D/VRML extensions you have
Major clients (tested by Daniel K. Schneider).
  • BS Contact VRML X3D VRML/X3D. Commercial software for Win/Mac/Linux, but 60 days of trial. A free version that includes a crawling banner is available. As of Aug 2010, the Linux versions is "RPM" only (see below for installing under Ubuntu).
Other clients
  • Free WRL the best known open-source (GPL) X3D and VRML browser for Unix/Linux/OS X. Perl/C based. Not X3D feature complete, almost VRML feature complete as of 2010, but getting there.... This is a long-term alive project.
  • OpenVRML, the other open-source X3D and VRML browser (not tested).
Specialized clients
  • Alpharis, a collective knowledge organization tool that uses X3D (?)
  • ManyOne is a Digital Universe. Features a modified Mozilla with a flux plugin for 3D contents. (dead as of Aug. 2010).
  • Kambi VRML game engine, main focus is on 3D games using VRML / X3D format (although other 3D model formats are also supported). Added Aug. 2010.
3D plugin selector
Installing BS Contact under Ubuntu

To install under Ubuntu as explained here, follow these steps: Get it like this (but take a newer version):

wget http://www.bitmanagement.de/developer/download/BSContact-7.1.07-4.i386.rpm

Extract the files with rpm2cpio (creates a cpio archive, then will extract the files to./opt/BSContact)

rpm2cpio BSContact-7.1.07-4.i386.rpm | cpio -imV

Move to /opt:

mv opt/BSContact /opt
rmdir opt

Tell Ubuntu it's there.

SETUP_INSTALLPATH=/opt/BSContact SETUP_OPTIONTAGS=icons /opt/BSContact/bin/postinstall --root --create icons

Serving X3D contents

Any web-server can serve X3D contents for stand-alone usage. You only have to make sure to configure the following mime-types in your web server:

 .x3dv  model/x3d+vrml
 .x3d   model/x3d+xml
 .x3db  model/x3d+binary

Alive multi user server software

See also: 3D interactive environments

Currently (sept. 2010) at least the following multi-user X3D server technology is available. There are probably additional commercial solutions. See also VRML. Resource-limited open-source projects seem to stick to this older standard. E.g. Vr4all is nice community and their technology does work. Also, it seems that some dead commercial platform code "floats" around, e.g. read this VRML Server forum.

DeepMatrix server (free)

DeepMatrix is an open-source Java server/client 3D multi-user system capable of both chat and shared events working in conjunction with VRML/X3D browsers that have Java EAI or External SAI. Currently (15:18, 16 May 2010 (UTC), this server works with the Deep MatrixIP9 client (see above). You may have to download the latest (non public) version from the FTP archive.

Bitmanagement's BS Collaborate (commercial)

“BS Collaborate designed for virtual reality applications from games up to cooperative work enables customer in combination with the basic visualization component BS Contact 7.2 (and higher) to realize real time communication between 3D objects like avatars in shared environments as well as collaborate working on 3D models with standard pc on the internet.” (BS Collaborate, retrieved Sept. 8 2010).

X3Daemon 3D Multiuser Network Server (beta)

“X3Daemon is middleware commercially available to developers, and is freely available to Office Towers users...” (not tested, except for at look at officetowers, which also can be used as free service for your VRML/X3D scene)

Dead multi user servers

It seems to Daniel K. Schneider that it will take time to attract more open source developers or companies to develop VRML/X3D-based multi-user servers. The ongoing pattern since the mid-1990's seems to be announcements, prototypes and then death of both the product and the companies. However, given that 3D is a "niche market" this is not too surprising. Let's recall the fate of some major technologies. IE (as of March 2009) still cannot handle XHTML and does not implement SVG. The SVG implementation of Firefox is partial only (doesn't include the "SMIL" tags. Firefox does not implement SMIL. Correct implementations of CSS3 and XSL-FO real-time players are other sore issues...

One reason why VRML and X3D is less popular than the sum of proprietry formats (in particular gaming engines) might be that other engines are optimized for speed. X3D, on the other hand, is much more flexible, in a scene any property of any object can change at any time (even if the user can't see the thing). Optimizing players to deal with lots of potentially changing geometry is already difficult. Now, propagating changes in multi-user environment over the Internet multiplies this challenge.

However, sticking to standards still seems to be best solution since code can be reused. Lively, Google's Flash 3D-based (?) chat environment, was terminated on december 2008. It would be interesting to know the reasons. ThePalace (the company who produced the Palace 2D environment) is dead. Active Worlds (the "second life of the late nineties) seems to be the only commercial proprietry 3D server that managed to stay alive over the years. It's too early to predict the fate of Second Life. It does look like a huge digital desert to me, but it may survive because of some specialized activities like fashion shows or virtual sex. The difference between Active Worlds and Second Life is that Active Worlds Inc. also sells servers you can install on your own machines. You also may consult 3D interactive environments for a longer list.

Below are some recently dead projects (probably most links are dead too now)

AbNet2 (free for non-commercial use)

“ABNet is a java communications client/server that turns a single-user VRML or X3D world into a multi-user virtual world environment. 3D avatars can interact and use shared events to provide a virtual experience similar to Secondlife and the Blaxxun platform. More generally, the communication framework of ABNet provides an asynchronous low-latency publish and subscribe environment using XML messages over TCP/IP.” (ABNet2 Software, retrieved Sept. 10 2010).

  • This project seems to be inactive as of Sept. 2010. Servers can't be downloaded anymore.
  • ABNet2 Software (Win/Linux/Mac)
  • VRMLWorld.net has been implemented with AbNet2.
Vivaty

Vivaty offers an online 3D chat service with a similar developer model as Second Life, but it's based on a real standard and therefore your contents can outlive the platform. It runs under Vista/XP as Firefox or IE plugin. You can design your own X3D scenes and then import to their server. There is also an interface with Facebook and AIM.

Vivaty closed on april 16, 2010 “The company’s revenue, pegged on the sales of its virtual currency Vivabux, was not substantial enough to cover its costs.” [1]. “Jay Weber, chief technical officer and co-founder, announced on the company’s blog that the site will close because its business of letting users create their own 3D virtual spaces has never taken off.” [2], retrieved 12:29, 25 August 2010 (UTC).

Mediamachines Flux World

In march 2007 Mediamachines announced Flux World (announcement March 2007), a server technology based Simple Wide Area Multi-User Protocol, or SWMP (pronounced "swamp"). The company is now gone and its assets went to Vivaty, e.g. the excellent Vivati Studio X3D authoring tool (formerly "Flux studio"). Vivaty then died on April 2010. No trace of the multi-user server. The free (but not opensource) X3D authoring tool may still be available from some places.

Blaxxun

[www.blaxxun.com/ Blaxxun] was one of the first VRML-based systems. The company at some point went broke in the early 2000's, but was alive again (2007) and dead again (2010?). I suspect that most of it's assets now belowng

Authoring tools

Then, check the web3d.org website. It has a good list of tools for X3D Development including a comparison of four authoring tools.

Modeling tools

See also 3D modeling. Several 3D modeling tools can export to X3D. Many X3D designers use a normal 3D or CAD modeling tool for creating individual objects and then export/import to a X3D structure editor (or X3D-aware programming editor) to build a scene.

  • Seamless3d, a free, open source 3D modeling software free and available for all under the MIT license. Can export to VRML, X3D XML and POV-RAY, imports VRML and X3D VRML. The Interface is a bit unusual, but (probably) easy to learn. Tutorials are provided. (testing, to do)
Combined Modeling / behaviors and scripting tools with a GUI
  • Vivati Studio (dead link) is from a company of the same name that died on April 16 2010. This product used to be called Flux studio before summer 2008. Vivatiy Studio was free for personal use! Authoring included modeling, animating, and scripting. Imports from other applications such as Sketchup, 3ds, Maya, Blender, and Unreal.
    • This tool is no longer available from any official web site, but copies may float around, e.g. here at DeepMatrix.org. We tested Studio Version 1.0 (forked from Flux 2.0) on Vista 32bit/ and Windows 7/64 bit. It runs fine on both.
    • Flux (software) (Wikipedia)
    • You Say You Want A Revolution? Well... by Len Bullard, March 2007. (Flux Studio tutorial).
  • BS Editor. Commercial (Euros 990)
    • “The BS Editor supports the application developer to program interactivity and behavior to objects and scenes. The geometry of 3D models shall be imported from leading authoring tools like 3ds max or Blender and can be integrated into applications by using BS Editor without notable VRML/X3D knowhow”, retrieved 11:20, 25 August 2010 (UTC). Only can edit *.wrl (VRML) if I understood right, therefore not a good buy.
  • SwirlX3D, 129 CAN$. This is a successor of popular Spazz3D
  • AC3D, Commercial (free trial). 3D modeler/editor that can export to X3D.
Structure editors
  • X3D-Edit Authoring Tool for Extensible 3D (X3D) Graphics. Written in open-source Java and XML using the Netbeans 6.7 platform.
    • X3D-Edit is a graphics file editor for Extensible 3D (X3D) that enables simple error-free editing, authoring and validation of X3D or VRML scene-graph files. Context-sensitive tooltips provide concise summaries of each VRML node and attribute. These tooltips simplify authoring and improve understanding for novice and expert users alike.
  • Submarine X3D, a free very simple X3D Editor for Linux, Mac OS X and Windows by Andrea Nardinocchi from University of Perugia.
  • For handcoding X3D, one also can use any XML editor that supports DTD or XSD, e.g. Xemacs.

Conversion, exporting and importing software

  • X3D encoding converter is an online service from InstantReality.org. It converts from VRML97 to X3D and from both to X3DOM (the proposed HTML 5 version of X3D)
  • VrmlMerge Merge multiple VRML files, convert to X3D. Free for non-commercial use. Read the howto. Command line:
java -jar VrmlMerge-[version].jar -merge inputfile.wrl [outputfile.wrl]
java -jar VrmlMerge-[version].jar -convert inputfile.wrl [outputfile.x3d]
java -jar VrmlMerge-[version].jar -images inputfile.wrl outputfile.wrl bitsPerColor
java -jar VrmlMerge-[version].jar -images2 inputfile.wrl [outputfile.wrl] 
  • AccuTrans 3D is a 3D object converter that supports many file formats and it is cheap ($20). As of 10/2010, it doesn't read Collada nor sketchup.

See also: File Translators & Utilities

Links

General / Indexes

Specifications

Main
Alternative reference documents
More and related specifications (extensions, additional)
  • X3dom is an attempt started in 2010 to integrate X3D with HTML5. “X3DOM (pronounced X-Freedom) is an experimental open source framework and runtime to support the ongoing discussion in the Web3D and W3C communities how an integration of HTML5 and declarative 3D content could look like. It tries to fulfill the current HTML5 specification for declarative 3D content and allows including X3D elements as part of any HTML5 DOM tree.” ([X3Dom.org], retrieved 12:29, 25 August 2010 (UTC)). Alpha implementations work with browers that implement WebGL (e.g. Firefox 4.0). See X3DOM for more information
  • See the X3dResources' Authoring Support section for additional resources (e.g. additional Schematron validation).
  • H-Anim (2004). ISO/IEC FCD 19774 (Avatar specification)

Developer communities

Overviews and comparisons

  • Interview with Research 2.0 (Interview with Stephen Waite (SW) from Research 2.0 and Anita Havele (AH), Web3D Consortium Executive Director, April 2010 ?)

Tutorials

(all retrieved Aug. 2010)

It may be a good idea to understand some very basic 3D principles, e.g. read How 3-D Graphics Work from how stuff works.

See also the resources to Learn X3D (web|3D Consortium)

Examples

There are many X3D/VRML examples on the web. However, many links collections and archives die or are not maintained. We shall add some more here, but maintaining links in web 3D is a nightmare (since most 3D Companies go broke after 3 or 5 years ....)

Simple examples (typically showing a single X3D feature)
  • Examples (X3D consortium resources). Follow up the links.
Example code collections
Projects and show cases
  • On-A-Slant Virtual Village. Interactive X3d. A Social Science Education Project.
  • X3D Scenarios and Case Studies (W3c)
  • Customer Case Studies (At BitManagement, probably the most "impressive" list and some very good examples in theory. However many links don't offer access to scenes, some are simply no good. Some annoying sites require IE/6 (I got version 8), old versions of Flash, BS contact etc....
Student projects
  • Educational Web3D, by Stephen Guynup, 15th ACM Conference on Web 3D Technlogy. Includes a description of a class and pointers to student projects.
Multi-user worlds

References

  • Behr, J., Dähne, P., and Roth, M. 2004. Utilizing X3D for immersive environments. In Proceedings of the Ninth international Conference on 3D Web Technology (Monterey, California, April 05 - 08, 2004). Web3D '04. ACM, New York, NY, 71-78. DOI=http://doi.acm.org/10.1145/985040.985051
  • Behr, J., Jung, Y., Keil, J., Drevensek, T., Zoellner, M., Eschler, P., and Fellner, D. 2010. A scalable architecture for the HTML5/X3D integration model X3DOM. In Proceedings of the 15th international Conference on Web 3D Technology (Los Angeles, California, July 24 - 25, 2010). Web3D '10. ACM, New York, NY, 185-194. DOI:10.1145/1836049.1836077 HTML/PDF
  • Brutzman, Don (2008), Computer Graphics Teaching Support using X3D: Extensible 3D Graphics for Web Authors, Nava Postagraduate School,
  • Brutzman, Don, and Daly, Leonard, X3D: Extensible 3D Graphics for Web Authors, Morgan Kaufmann Publishing, 2007. 468 pages Book website
  • Chittaro, L. and R. Rano (editors) (2007). Web3D Technologies in Learning, Education and Training, Computers & Education Volume 49, Issue 1, Pages 1-130 (August 2007). Table of contents for the special issue)
  • Daly, Leonard and Brutzman, Don, âX3D: Extensible 3D Graphics Standard,â Standards in a Nutshell column, IEEE Signal Processing Magazine, vol. 24 no. 6, November 2007, pp. 130-133.Y
  • Davis, Wiki A. (2007), The frontier of education: Web 3D, The Cool Cat Teacher, Blog Entry. HTML
  • Ieronutti, L. and Chittaro, L. 2007. Employing virtual humans for education and training in X3D/VRML worlds. Comput. Educ. 49, 1 (Aug. 2007), 93-109. DOI 10.1016/j.compedu.2005.06.007
  • Jung, Y., Recker, R., Olbrich, M., and Bockholt, U. 2008. Using X3D for medical training simulations. In Proceedings of the 13th international Symposium on 3D Web Technology (Los Angeles, California, August 09 - 10, 2008). Web3D '08. ACM, New York, NY, 43-51. DOI=10.1145/1394209.1394221
  • Nigel W. John, The impact of Web3D technologies on medical education and training, Computers & Education, Volume 49, Issue 1, Web3D Technologies in Learning, Education and Training, August 2007, Pages 19-31, ISSN 0360-1315, DOI: 10.1016/j.compedu.2005.06.003. Abstract/HTML/PDF
  • Osvaldo Gervasi, Donald P. Brutzman (Eds.): Proceeding of the Twelfth International Conference on 3D Web Technology, Web3D 2007, Perugia, Italy, April 15-18, 2007. ACM 2007, ISBN 978-1-59593-652-3 TOC.