From b7d1036bb2f658e7052755532738cf05575932ee Mon Sep 17 00:00:00 2001 From: Robert Osfield Date: Fri, 19 Apr 2002 16:21:18 +0000 Subject: [PATCH] updated the introduction.html, still not complete but getting there. No edited for typo's yet :-) --- doc/introduction.html | 49 +++++++++++++++++++++++++++++++++++++------ 1 file changed, 43 insertions(+), 6 deletions(-) diff --git a/doc/introduction.html b/doc/introduction.html index 56e1fe6e8..928975aa0 100644 --- a/doc/introduction.html +++ b/doc/introduction.html @@ -11,8 +11,11 @@

Welcome to OpenSceneGraph project!

-

In this document I'll introduce what a scene graph is, what the OpenSceneGraph project encompasses, and provide tips on how to learn how to use it -and to contact or contribute to the OpenSceneGraph community. +

The OpenSceneGraph is an Open Source, Cross Platform (Widows, Linux, Mac OSX, FreeBSD, Irix, Solaris), +Standard C++ and OpenGL based graphics development library, uses range from visual simulation, games, +virtual reality, sceintific visualization and graphics research. This pages introduces a +what scene graphs are, why graphics developers use them, and details about the OpenSceneGraph, +project, how to learn how to use it and contribute to the OpenSceneGraph community.

Robert Osfield, @@ -25,12 +28,21 @@ April 2002.

Its a tree! Quite simply one the best and most reusable datastructures invented.Typically drawn schematically as root at the top, leaves at the bottom. It all starts with a topmost root node which encompasses your whole virtual world, be it 2D or 3D. The world is then broken down -into hierachy of nodes represent either a spatial grouping of objects, -set the position of or animate objects,. or define a logical relationship between objects such as to manage +into hierachy of nodes representing either a spatial grouping of objects, +setting the position of objects, animating objects,. or define a logical relationship between objects such as to manage the various states of a traffic light.The leaves of the graph represent the phyical objects themselves, the drawable geometry and their material properties.

+

A scene graph isn't a complete game or simulation engine, although may be one of the main +components of such an engine, it's primary focus is representing your 3d worlds, and rendering it efficiently. Physics models, collision detection and audio are left to other development libraries that a user will +integrate with.. The fact that scene graphs don't typically integrate all these features +is actually a really good thing, it aids interoprability with clients own applications +and tools they wish to use and allows them to serve many varied markets from games, visual +simulation, virtual reality, scientific and commerical visulasation, training thruogh to modelling +programs. +

+

Why use a Scene Graph - Performance, Productivity, Portability and Scalability.

@@ -69,13 +81,38 @@ then moving from platform to platform can be a simple as recompiling your source automatically to account for differences in graphics performance across a range of machines, scene graphs also make it much easier to manage complex hardware configurations, such as clusters of graphics machines, or multiprocessor/multipipe systems such as SGI's Onyx. A good scene graph -will allow the developer to concentrate on developing their own application while rendering +will allow the developer to concentrate on developing their own application while the rendering framework of the scene graph handles the differnt underlying hardware configurations.

-

What the OpenSceneGraph encompasses?

+

So what about the OpenSceneGraph project?

+ +

+The OpenSceneGraph is Open Source, all the source to is published under the +GNU Library General Public License (LGPL) which allows both open source and closed source +projects to use, modify and distribute it freely as long its usage complies with the +LGPL. The project has been developed over the last four years, initliated by Don Burns, and +then taken over by Robert Osfield who leads the continues to lead project, there are many +other contributors to the library, for a full list check out the AUTHORS file. Both Robert +and Don now work on the OpenSceneGraph in a professional capaciity provide consultancy +and bespoke developments ontop the library, and are also colloborating on the book.Work on +the core scene graph and support of public mailing list remains unpaid as are the +contributions of the rest of the communinity, but this hasn't impacted the quality of the +source or support which once you get stuck in you grow to appreciate. +

+ +

+The project itself is written entitely in Standard C++ and OpenGL, makes full use of STL +and Design Patterns, and leverages the open source development model to provide clean, highly portable, +and flexible scene graph. The project is current in alpha, which means part of the API are still to be +developerd, or subjec to change, but the vast majority of the scene graph is there, and a beta will +be published within the next few months, wiht a 1.0 release in late summer. Despite the +alpha development status, the project has alrady earned the reputation as one of the leading +open source scene graph, and is establishing itself a vialbe alternative to the commericial +scene graphs. Numerous companies, university researchers and graphics enthusasts have +already adopted their project, and a from all over the world.