1 / 22

Pieter Jorissen* Maarten Wijnants, Wim Lamotte

Using Collaborative Interactive Objects and Animation to Enable Dynamic Interactions in Collaborative Virtual Environments. Pieter Jorissen* Maarten Wijnants, Wim Lamotte. Overview. Interactions in CVEs Interactive Objects approach Avatars in CVEs

tuyet
Download Presentation

Pieter Jorissen* Maarten Wijnants, Wim Lamotte

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Using Collaborative Interactive Objects and Animation to Enable Dynamic Interactions in Collaborative Virtual Environments Pieter Jorissen* Maarten Wijnants, Wim Lamotte

  2. Overview • Interactions in CVEs • Interactive Objects approach • Avatars in CVEs • Creating more flexible avatar interaction • User input • Network setup • Network traffic • Results • Future Work

  3. Collaborative Virtual Environments (CVEs) • Immersive 3D World • Multiple participants (distributed) • Users can interact through an avatar • Navigate • Interact with objects/other users • Avatar represents the user and their interactions • Position/orientation (3D model) • Interactions (animations) • (other: personality, emotion,…)

  4. Interactions in CVEs • Traditional • Navigation • Direct interaction techniques for actor - object interactions • Advanced behavior = case specific • Hard-coded in application • Result: • Not very flexible • Not runtime extensible • Little reusability

  5. Interactions in CVEs

  6. Goal Make CVE worlds more interactive Generalize CVE interactions • Make interactions independant of the application • Allow new objects to be introduced at any time • Make no distinction between different kinds of object interactions (avatars, objects, AI agents) • Allow every object/avatar to interact with every other object/avatar in the world • Single scheme for all CVE interactions • Keep netwerk traffic as low as possible

  7. Our Approach • Put interaction info and behaviors in the object description • Describe behaviors in parameterized scripts • Put only the general interaction scheme in the application (script handling, communication) • Interaction layer communicates with the objects • Objects can communicate with other objects through links and messages

  8. Our Approach

  9. Interactive Object Description • Object Properties • Parts, transformations, models, id, constraints,… • Interaction Properties • Commands, triggers, interaction zones • Object Behaviors • Scripts • Trigger – script coupling • XML • Easy to read, easy to understand

  10. Interaction Layer

  11. Interactive Worlds • Advantage • Objects/parts are easy to modify (runtime) • Objects/parts are easy to reuse • New objects can be introduced at any time • Interaction information could be used for planning • Information can be used for network optimizations • Disadvantage • More work in the modeling stage • Less programming (more scripting) • High reusability of object description

  12. Avatars in CVEs • Evolution: • Avatar is the users means of interaction • Proper avatar animation increases feeling of immersion

  13. Avatar Animation in CVEs • Skeletal animation + Keyframed actions • Advantages • Low memory use • Computationally inexpensive • Disadvantages • Lack of flexibility (fixed set of animations) • More flexibility => Use inverse kinematics • Very flexible • Computationally more expensive

  14. Adding IK to the CVE avatar • “Arm” movement (grasping, pointing, pushing,...) • Store IK info separate from animated model • IK joint chain • End effector • Joint constraints • Joint reach (bounding box) • Not human avatar specific !!! • Direct control

  15. User Input • Direct 3D input • Keyboard • Slow • Unintuitive • Difficult context switch • No reference • Microscribe-3D • Easy context switch • Intuitive => fast • No force feedback

  16. Network setup

  17. Network Traffic • Startup: get world from server TCP • Updates: UDP + multicast • Keep it as low as possible!!! • Use interactive object information (at server) • Object/part constraints  determine possible moves • Animation • Send only high level description (animID, start, stop) • Animation synchronization not perfect, but unnecessary • Inverse Kinematics • Send only position of end effector • Calculate joints locally (no perfect synch for all joints)

  18. Results • Collaborative World 1 • Hand interaction 1 • Hand Interaction 2

  19. Future Work • Adding AI agents • Large scale testing • Coupling to physical simulation engine • Head tracking + Stereo vision • Add force feedback • Usability study

  20. QUESTIONS ?

More Related