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VRML: New Modeling Language for creating 3D Web Pages
Posted On June 25, 2007 by Ramdas S filed under Miscellaneous
HTML is a two-dimensional standard for publishing content on the web. HTML facilitates hyper linking and cross-referencing. It provides only static pages, which work well for text-based information and two-dimensional drawings.
Virtual Reality Modeling Language (VRML) allows users to create three-dimensional images that can be viewed from any angle. VRML, a subset of 3D graphics, is a language for describing multi-participant interactive simulations; virtual worlds networked via the global Internet and hyperlinked with the World Wide Web. All aspects of virtual world display, interaction and internetworking can be specified using VRML, without being dependent on special gear like head-mounted devices (HMD).
The term Virtual Reality is overloaded with many definitions. One of the definitions given is as follows. “Virtual Reality is the presentation of a 3D scene of sufficient quality to evoke a perceptual response similar to a real scene”. The 3D scene is often called as Virtual World and the word Virtual Reality is commonly abbreviated as VR.
VRML was theoretically proven possible in the “Cyber space paper”, written by Mark Pesce, Anthony Parisi and Peter Kennard in 1993. As a proof of concept, Pesce and Parisi developed the first VRML browser, Labyrinth. Subsequently, a mailing list was established for those interested in developing this technology. A community quickly formed from this list and has been leading the development of VRML. VRML was conceived at the first annual WWW conference in Geneva, Switzerland, in 1994. In May1995, VRML 1.0 was accepted by the VRML Architecture Group (VAG) as the standard specification.
The major objectives of VRML are platform independence, expressibility and extensibility. VRML 2.0 was planned to offer more ambitious features such as multi-user interaction or autonomous creations that can sense and react to their environment.
VRML is simple like HTML. A simple specification encourages the development of more browsers, which leads to competition that should boost the development of higher quality implementations.
VRML is designed to scale in three ways. First, it should be theoretically possible for VRML browsers to handle a world distributed across the Internet that contains millions or billions of objects. Secondly, it should work well when used with both very powerful and very expensive machines, allowing the VRML browser to trade off images or simulation quality for improved performance and to scale with increased hardware performance. Third, VRML worlds should scale well with network performance, from the 14.4K modems that are common today to multi- gigabyte connections that might become common in the future.
VRML file consists of the following major functional components – Header, Scene graph, Prototype and Event routing. The contents of VRML file are processed for presentation and interaction by a machine form known as browser.
Header:
For easy identification of VRML files, every VRML file shall begin with
#VRML V 2.0 <encoding type> [comment] <line-parameter>.
The Header is a single line of UTF8 text identifying the file as a VRML file and identifying the encoding type of the file. It may also contain additional semantic information. The identifier UTF8 indicates a clear text encoding that allows for international characters to be displayed in VRML. It may also contain additional information.
# VRML 2.0 utf 8
Scene Graph:
It contains nodes, which describe objects and their properties. It contains hierarchically grouped geometry to provide an audiovisual representation of objects, as well as nodes that participate in the event generation and routing mechanism. A Scene graph is to VRML what a bitmap is for 2D graphics. It is the structure of the world being created. A VRML Scene graph comprises a group of objects (Box, Cone, Cylinder and Sphere) when rendered; these objects exist in 3D space. They have depth, height and width.
Shape {
Geometry Cone {}
}
Prototypes:
It allows the set of VRML node types to be extended by the user. Prototype definitions can be included in the file in which they are used or defined externally. The prototype mechanism allows you to collect pieces of a VRML scene so that they can be reused, but these parts can be made to look like any other VRML node.
Event Routing:
Some VRML nodes generate events in response to environmental changes or user interaction. Event routing gives authors a mechanism, separate from the scene graph hierarchy, through which these events can be propagated to effect changes in other nodes. Once generated, events are sent to their routed destinations in timely order and processed by the receiving node.
VRML can be viewed inside an HTML browser as long as that browser has the proper plug-in, which is also available at the web site http://www.vrml.sgi.com/cosmoplayer. Major browsers support VRML.
VRML navigation is the primary interaction in any VRML scene and good design. VRML 2.0 allows the author to control how the user is navigating the world through the NavigationInfo node. The viewer can also control his or her navigation via browser controls. There are two general modes of movement in VRML, the viewer moving around the object and the viewer moving the object. VRML file extensions are of three types – .wrl, .wrz and .wrl.gz.
fig – 1 ( INSERT THE FIG1.BMP)
Sample program:
We can use VRML editors or any text editors like notepad. Type the following code:
# VRML V2.0 utf8
Transform {
translation -2 0 -2
children Shape {
appearance Appearance {
material Material {
diffuse Color 0 0.7 0.2
}
}
geometry Box {size 2 2 2}
}
}
Save as test.wrl. To run the code, open the browser, select file -> open -> test.wrl. Check whether the VRML plug-in is available or not, like e.g. Cosmo Player software.
fig – 2 ( INSERT THE FIG2.BMP)
This ends our sojourn to the virtual world.
The author is a lecturer at NI College of Engineering , Tamil Nadu. He can be contacted at j_ramar@yahoo.com.
Virtual Reality Modeling Language (VRML) allows users to create three-dimensional images that can be viewed from any angle. VRML, a subset of 3D graphics, is a language for describing multi-participant interactive simulations; virtual worlds networked via the global Internet and hyperlinked with the World Wide Web. All aspects of virtual world display, interaction and internetworking can be specified using VRML, without being dependent on special gear like head-mounted devices (HMD).
The term Virtual Reality is overloaded with many definitions. One of the definitions given is as follows. “Virtual Reality is the presentation of a 3D scene of sufficient quality to evoke a perceptual response similar to a real scene”. The 3D scene is often called as Virtual World and the word Virtual Reality is commonly abbreviated as VR.
VRML was theoretically proven possible in the “Cyber space paper”, written by Mark Pesce, Anthony Parisi and Peter Kennard in 1993. As a proof of concept, Pesce and Parisi developed the first VRML browser, Labyrinth. Subsequently, a mailing list was established for those interested in developing this technology. A community quickly formed from this list and has been leading the development of VRML. VRML was conceived at the first annual WWW conference in Geneva, Switzerland, in 1994. In May1995, VRML 1.0 was accepted by the VRML Architecture Group (VAG) as the standard specification.
The major objectives of VRML are platform independence, expressibility and extensibility. VRML 2.0 was planned to offer more ambitious features such as multi-user interaction or autonomous creations that can sense and react to their environment.
VRML is simple like HTML. A simple specification encourages the development of more browsers, which leads to competition that should boost the development of higher quality implementations.
VRML is designed to scale in three ways. First, it should be theoretically possible for VRML browsers to handle a world distributed across the Internet that contains millions or billions of objects. Secondly, it should work well when used with both very powerful and very expensive machines, allowing the VRML browser to trade off images or simulation quality for improved performance and to scale with increased hardware performance. Third, VRML worlds should scale well with network performance, from the 14.4K modems that are common today to multi- gigabyte connections that might become common in the future.
VRML file consists of the following major functional components – Header, Scene graph, Prototype and Event routing. The contents of VRML file are processed for presentation and interaction by a machine form known as browser.
Header:
For easy identification of VRML files, every VRML file shall begin with
#VRML V 2.0 <encoding type> [comment] <line-parameter>.
The Header is a single line of UTF8 text identifying the file as a VRML file and identifying the encoding type of the file. It may also contain additional semantic information. The identifier UTF8 indicates a clear text encoding that allows for international characters to be displayed in VRML. It may also contain additional information.
# VRML 2.0 utf 8
Scene Graph:
It contains nodes, which describe objects and their properties. It contains hierarchically grouped geometry to provide an audiovisual representation of objects, as well as nodes that participate in the event generation and routing mechanism. A Scene graph is to VRML what a bitmap is for 2D graphics. It is the structure of the world being created. A VRML Scene graph comprises a group of objects (Box, Cone, Cylinder and Sphere) when rendered; these objects exist in 3D space. They have depth, height and width.
Shape {
Geometry Cone {}
}
Prototypes:
It allows the set of VRML node types to be extended by the user. Prototype definitions can be included in the file in which they are used or defined externally. The prototype mechanism allows you to collect pieces of a VRML scene so that they can be reused, but these parts can be made to look like any other VRML node.
Event Routing:
Some VRML nodes generate events in response to environmental changes or user interaction. Event routing gives authors a mechanism, separate from the scene graph hierarchy, through which these events can be propagated to effect changes in other nodes. Once generated, events are sent to their routed destinations in timely order and processed by the receiving node.
VRML can be viewed inside an HTML browser as long as that browser has the proper plug-in, which is also available at the web site http://www.vrml.sgi.com/cosmoplayer. Major browsers support VRML.
VRML navigation is the primary interaction in any VRML scene and good design. VRML 2.0 allows the author to control how the user is navigating the world through the NavigationInfo node. The viewer can also control his or her navigation via browser controls. There are two general modes of movement in VRML, the viewer moving around the object and the viewer moving the object. VRML file extensions are of three types – .wrl, .wrz and .wrl.gz.
fig – 1 ( INSERT THE FIG1.BMP)
Sample program:
We can use VRML editors or any text editors like notepad. Type the following code:
# VRML V2.0 utf8
Transform {
translation -2 0 -2
children Shape {
appearance Appearance {
material Material {
diffuse Color 0 0.7 0.2
}
}
geometry Box {size 2 2 2}
}
}
Save as test.wrl. To run the code, open the browser, select file -> open -> test.wrl. Check whether the VRML plug-in is available or not, like e.g. Cosmo Player software.
fig – 2 ( INSERT THE FIG2.BMP)
This ends our sojourn to the virtual world.
The author is a lecturer at NI College of Engineering , Tamil Nadu. He can be contacted at j_ramar@yahoo.com.