Overview of VRML2

The VRML2 translator lets you export Maya scene files into VRML2 format. NURBS surfaces are tessellated to polygons and then output.

NoteThe VRML2 translator does not output all of the Maya feature set.

VRML2 Features

Outputs

polygon geometry
NURBS surfaces - tessellated into either triangles or quads
hierarchy structure if wanted
VRML2 primitives (if tagged)
shader parameters
textures - SGI RGBA image format
rigid TRS animation
vertex animation
Camera information
Light information

Commands

There is a MEL command included in the VRML2 translator. This command, vrml2Tags, let you define dynamic attributes onto objects that the translator queries and uses to define the output file.

Attributes

The following dynamic attributes can be defined and used with this translator.

userAnimated boolean: On = force vertex animation processing
VRML2Primitive: long, cube/plane
VRML2Billboard: long, camera facing/Y facing/Z facing

Files required to use this plug-in

The files required for use of this plug-in are:

vrml2Export.lib (Mac OS X), vrml2Export.so (Linux), or vrml2Export.mll (Windows)
vrml2TranslatorOpts.mel

Source code can be found in:

(Linux) /devkit/obsolete/games/vrml2Export

(Windows) Program Files\Autodesk\Maya2011\devkit\obsolete \games\vrml2Export

(Mac OS X) Applications/maya2011/devkit/obsolete/games/vrml2Export

Limitations

On Mac OS X, the VRML2 Exporter does not export textures.
The range for the light intensity in VRML2 is [0 to 1.0]. Maya doesn’t have a limit. The translator assumes a scaling of [0-100] and divides down the Maya setting.
No checks are made for negative scales. VRML2 defines scale to be greater than 0.
Only SGI RGB/RGBA file textures are output. Microsoft’s VRML2 viewer does not support this format. Cosmoplayer does read the texture files on both Linux and Windows systems. You may have to set up the file associations on the Windows platform to run Netscape instead of Explore if the auto launch feature is used on Windows systems.
You need to turn on Sample for Texture Options to get proper rotation of textures.
There may be memory leaks in the translator. This is because not all of the intermediate internal structures are deleted (for instance, animating NURBS surfaces will create a noticeable memory leak with Maya 1.0 due to the tesselation).
Vertex animation is based on the connection of the inMesh attribute, so this will cause more geometry to be considered animated that may be. For final results, you may want to clean up the history of non-animated tweaks.
A check for dynamic attribute called userAnimated to force usage has been added. Use the Add Attribute command to add userAnimated as a boolean flag and then set it ON for those objects that you want to force the vertex animation to recognize and use. This will mostly be for those objects that don’t have history and an inMesh connection.
Instanced geometry is output multiple times but doesn’t get reused.