3D Character Animation

MetaVR™ Virtual Reality Scene Generator™ (VRSG™) has integrated support for high-quality animated 3D characters. The character animation and rendering is designed to support hundreds of characters simultaneously within the field of view while maintaining a high frame rate.

	Afghan village characters from a scenario on MetaVR's virtual Afghanistan terrain.

VRSG is delivered with a model library of over 285 characters and weapons in MetaVR's model format. You can immediately configure and use these models in VRSG. Additionally, the library includes nearly 300 animations for the characters in the game industry standard BVH format; the animations portray all commonly used appearances required by the DIS protocol. You can also use your own custom characters, weapons, and animations in VRSG.

The following video clip shows a digging animation performed by two insurgent characters, burying an IED in a real-time VRSG scenario that takes place on MetaVR's virtual Afghanistan terrain.

This animation requires FlashPlayer version 9 or better.

MetaVR’s 3D characters consist of an inner skeleton and an outer “skin” mesh. The skin mesh is deformed in real-time according to the position of the skeleton. This technique prevents cracks or interpenetrating surfaces; it also creates realistic looking animations without requiring any excess geometry. In VRSG, the deformation is computed entirely by the graphics card to maximize performance. VRSG computes transitions between animations by smooth blending from one animation to the next. This approach minimizes discontinuities and makes it easier to add custom animations without creating hand-authored transitions.

Adding characters to VRSG

Like a vehicle entity, a 3D character can be configured as an entity in VRSG through the ModelMap.ini configuration file. You can assign any character model to a DIS lifeform entity by its DIS enumeration. You can optionally associate a weapon with the character. A character with a weapon can respond to DIS protocol messages to deploy or fire its weapon. When an entity's appearance is updated over DIS, an animation is automatically assigned. (Note that for customers who currently use Boston Dynamics' Di-Guy, VRSG continues to support Di-Guy. You can use both MetaVR's characters and Di-Guy characters together in a VRSG session.)

	VRSG rendering of a scene on MetaVR's virtual Afghanistan terrain featuring characters from MetaVR's character libraries and a Jackal vehicle from the military vehicle library.

MetaVR’s 3D character library is delivered with a set of animation files in the standard BVH motion capture format. Character animations are supported with a standard skeleton hierarchy based on MotionBuilder’s skeleton hierarchy.

Creating your own characters to use in VRSG

In addition to using in VRSG the models from MetaVR's 3D character library, you can create your own human characters in well-known modeling tools such as Autodesk 3ds Max or Autodesk Maya using MetaVR’s character template and conversion utility that converts character models from the popular FBX format into MetaVR’s model format.

MetaVR's character template includes an armature object containing a hierarchy of bones that matches MetaVR's BVH rig, as well as a low polygon mesh that is used by VRSG’s physics.

The example above shows the preparation of a model in Autodesk 3ds Max prior to exporting it in FBX format for subsequent conversion to MetaVR's model format. After converting the model to MetaVR’s model format, you can inspect the model in MetaVR’s Model Viewer. You can test an animation with your character displayed in the Model Viewer by dragging one of the BVH animations from the MetaVR character model library to the Model Viewer window.  You can then inspect the animation playing in real time.

MetaVR's FBX conversion utility is available upon request to customers under active maintenance. To request MetaVR's FBX conversion utility and character template, send email to support@metavr.com.

Creating your own character animations

MetaVR characters use the MotionBuilder standard skeleton hierarchy for animation. MotionBuilder is one of the strongest animation tools available, ideal for building character animations for simulations and games.

This approach enables you to import motion-capture data or use COTS software to create custom animations, and in turn use MotionBuilder to transfer your data to MetaVR’s skeleton hierarchy.

The character model library includes a control rig in MotionBuilder’s FBX format that contains the standardized skeleton used by all MetaVR character models. You can use MetaVR’s control rig as the starting point of any new animations. Once your data is in MotionBuilder, you can create an optimized looped animation and export it in BVH format for use in VRSG.

First person control

To simulate interaction among human characters in a networked VRSG session, you can use VRSG's First Person Simulator (FPS) to control your character and view the scene from the character's point of view. An FPS character can take on the persona of any VRSG character model, and optionally can hold and fire a weapon. FPS provides the means to simulate an individual while training for military operations.