Transcript COLLADA™ Khronos Group

Нижегородский государственный университет им. Н.И.Лобачевского
Факультет вычислительной математики и кибернетики
COLLADA™
Khronos Group
COLLAborative Design Activity for establishing an
interchange file format for interactive 3D applications
Введение в стандарт COLLADA
проф. Турлапов В.Е.,
[email protected]
COLLADA From Wikipedia
COLLADA is a COLLAborative Design Activity for
establishing an interchange file format for interactive 3D
applications.
COLLADA is managed by the not-for-profit technology
consortium, the Khronos Group.
COLLADA defines an open standard XML schema for
exchanging digital assets among various graphics
software applications that might otherwise store their
assets in incompatible file formats.
COLLADA
Filename extension
.dae
Developed by
Sony Computer Entertainment,
Khronos Group
Initial release
October 2004
Latest release
1.5.0 / August 2008
Type of format
3D computer graphics
Extended from
XML
Website
collada.org
COLLADA documents that describe digital assets are XML files, usually identified with a .dae (digital
asset exchange) filename extension.
History. Originally created by Sony Computer Entertainment as the official format for PlayStation 3 and
PlayStation Portable development, it has since become the property of the Khronos Group, a member-funded
industry consortium, which now shares the copyright with Sony. Several graphics companies collaborated with
Sony from COLLADA's beginnings to create a tool that would be useful to the widest possible audience, and
COLLADA continues to evolve through the efforts of Khronos contributors. Early collaborators included Alias
Systems Corporation, Criterion Software, Autodesk, Inc., and Avid Technology. Dozens of commercial game
studios and game engines have adopted the standard.
COLLADA From Wikipedia
Tools and compatibility
COLLADA was intended originally as an intermediate format for transporting data from one digital content
creation (DCC) tool to another. Applications exist to support that usage for several DCCs, including Maya (using
ColladaMaya); 3ds Max (using ColladaMax); Poser (v.7.0); LightWave 3D (version 9.5); Cinema 4D (MAXON);
Softimage|XSI; Side Effect's Houdini; MeshLab; CityEngine, SketchUp, Blender, modo and Strata 3D.
COLLADA.dae files can be used in Adobe Photoshop software since version CS3. Game engines, such as Unreal
engine, have also adopted this format. The basic support for viewing the format is also built-in in the Mac OS X
10.6 Snow Leopard.
Two open-source utility libraries/projects are available to simplify the import and export of COLLADA
documents: the COLLADA DOM library and the OpenCOLLADA project. The COLLADA DOM is generated at
compile-time from the COLLADA schema. It provides a low-level interface that eliminates the need for handwritten parsing routines, but is limited to reading and writing only one version of COLLADA, making it difficult to
upgrade as new versions are released. The OpenCOLLADA project provides the next generation plugins for 3ds
Max & Maya and the sources of utility libraries which were developed for the plugins.
An additional open-source utility library is available from Feeling Software: FCollada. In contrast to the
COLLADA DOM, Feeling Software's FCollada provides a higher-level interface. FCollada is used in ColladaMaya,
ColladaMax, and several commercial game engines. The development of the open source part was discontinued
by Feeling Software in 2008.
Some applications have adopted COLLADA as their native format or as one variety of native input rather
than simply using it as an intermediate format. Google Earth (release 4) has adopted COLLADA (1.4) as its native
format for describing the objects populating the earth. Users can simply drag and drop a COLLADA (.dae) file on
top of the virtual Earth. Alternatively, Google SketchUp Pro can also be used to create.kmz files, a zip file
containing a KML*) file, a COLLADA (.dae) file, and all the texture images.
*) Keyhole Markup Language (KML) is an XML-based language schema for expressing geographic annotation and visualization on Web-based, two-dimensional
maps and three-dimensional Earth browsers. KML was developed for use with Google Earth, which was originally named Keyhole Earth Viewer. It was created
by Keyhole, Inc, which was acquired by Google in 2004.
COLLADA From Wikipedia
COLLADA Physics
As of version 1.4, physics support was added to the COLLADA standard. The goal is to allow content creators
to define various physical attributes in visual scenes. For example, one can define surface material properties
such as friction. Furthermore, content creators can define the physical attributes for the objects in the scene.
This is done by defining the rigid bodies that should be linked to the visual representations. More features
include support for ragdolls, collision volumes, physical constraints between physical objects, and global
physical properties such as gravitation.
Physics middleware products that support this standard include Bullet Physics Library, Open Dynamics
Engine, PAL and NVIDIA's PhysX. These products support by reading the abstract found in the COLLADA file and
transferring it into a form that the middleware can support and represent in a physical simulation. This also
enables different middleware and tools to exchange physics data in a standardized manner.
The Physics Abstraction Layer provides support for COLLADA Physics to multiple physics engines that do not
natively provide COLLADA support including JigLib, OpenTissue, Tokamak physics engine and True Axis. PAL also
provides support for COLLADA to physics engines that also feature a native interface.
Versions
Links
1.0: October 2004 ; 1.2: February 2005 ; 1.3: June 2005
1.4.0: January 2006; added features such as character skinning and morph targets,
rigid body dynamics, support for OpenGL ES materials, and shader effects for
multiple shading languages including the Cg programming language, GLSL, and HLSL.
First release through Khronos.
1.4.1: July 2006; primarily a patch release.
1.5.0: August 2008; added kinematics and B-rep as well as some FX redesign and
OpenGL ES support (Retrieved 2008-10-13)
Official homepage
OpenCOLLADA Project
ColladaLoader - to
load and visualize
COLLADA files in real
time using OpenGL.
GLC_Player
COLLADA. OpenCOLLADA Project & GLC Player
OpenCOLLADA Project
COLLADA SDK within various DCC
tools like 3ds Max, Maya, Blender, ...
(OpenCOLLADA Project)
The OpenCOLLADA SDK is open
source software and released under
the MIT license. The latest plugins are
released under a proprietary free to
use license.
GLC_Player
is an Open Source 3D viewer
used to view 3d models
(COLLADA, 3DXML, OBJ 3DS STL
OFF COFF Format) and to
navigate easily in these models.
(GLC_Player )
COLLADA. Official homepage
COLLADA Overview
COLLADA - 3D Asset Exchange Schema
COLLADA™ defines an XML-based schema to make it easy to transport 3D assets between applications - enabling
diverse 3D authoring and content processing tools be combined into a production pipeline. The intermediate
language provides comprehensive encoding of visual scenes including: geometry, shaders and effects, physics,
animation, kinematics, and even multiple version representations of the same asset.
COLLADA FX enables leading 3D tools to work effectively together to create shader and effects applications and
assets to be authored and packaged using OpenGL® Shading Language, Cg, CgFX, and DirectX® FX
COLLADA at a glance
COLLADA defines an XML Namespace and database schema to make it easy to transport 3D assets between
applications without loss of information, enabling diverse 3D authoring and processing tools to be combined into a
content production pipeline.
COLLADA 1.5
COLLADA 1.5 is the newest specification that provides all of the features found in the stable COLLADA 1.4 schema
plus several new features that enable users of CAD, GIS, and Automation applications to enjoy the benefits of open
standard royalty free content format.
COLLADA 1.5.0 Specification (Last updated: Oct 2008, local link)
COLLADA PDF Overview Click here (Dec 2008)
COLLADA Community
The Khronos Group is host to the COLLADA community web site (http://collada.org) . There are also a growing
number of open source software projects that can help you to develop your COLLADA applications more quickly:
COLLADA Document Object Model (DOM) (also includes RT, FX, and Refinery tools)
COLLADA Test Model Bank (exchange test models for COLLADA development projects)
COLLADA 1.5. New features
COLLADA 1.5. New features
COLLADA 1.5. New features
COLLADA 1.5. Specification & Content
COLLADA 1.5.0 Specification (Last updated: Oct 2008, local link)
Библиотеки
Примеры