DESIGNING 3D WEB USING VRML

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DESIGNING 3D WEB USING VRML

• Bob Hobbs
• Introduction to Virtual Reality and Simulation
• CE00166-1

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Development Cycle
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Target Platform
To establish your target computer platform you
must ask yourself the following questions
1.Who will be using my Synthetic Environment?
2.What hardware and software are they
likely to be using? 3.How will my
Synthetic Environment be delivered to them?
4.When will my Synthetic Environment
be finished?
4
Understand the Features Limitations of the
Technology

• General Limits
• Polygon Count
• Textures
• Lights
• Sounds
• Filesize
• VRML Specific Limits
• No Shadow Casting
• No Reflections
• Performance
• Plug-in Compatibility/Compliance

5
Storyboard and Project Documentation

• Target Platform
• Preliminary Research
• Storyboard Sketches
• Interactivity
• User Interface
• Resource Requirements
• Project Timeline and Milestones

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ImportingFrom ModelingSoftware

• Find suitable model
• Modify
• Reduce Polygon Count

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Edit Appearance

• Material Properties
• Diffuse - colour of object
• Specular - highlight colour on shiny objects
• Emissive - glow colour
• Ambient intensity
• Shininess - changes the size of the highlight
• Transparency

• Apply Textures
• File Formats
• PNG - Portable Network Graphics
• JPEG - Joint Photographic Experts Group
• GIF - Graphics Interchange Format
• MPEG1 - Motion Picture Experts Group

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Assemble Scene

• Modular Assembly
• Time_consuming
• Allows behaviours to be attached more easily
• Use DEF to allow cloning
• Use scene tree methodology
• Using Inlines
• Uses existing model
• Scaling
• Cannot animate sub-assemblies

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Environmental Objects

• Background
• Texture
• Gradient
• Single Colour

• Adding Lights
• No shadows
• More Faces - better shading
• Limit to number of lights
• Different types of lighting

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Lighting
Directional light Point Light Spot
Light Headlight - always on (deactivate after
adding lighting)
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Add Animation

• Key Frame animation
• Interpolation
• Tweening
• Storyboard

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Complex Interactions

• Create Drag Sensors
• Create Switch Nodes
• Scripting

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Sensors

• TouchSensor User clicks on, or rolls mouse
  pointer over object to trigger even
• PlaneSensor User clicks and drags to move
  an object in the local X-Y plane
• (left-right, up-down)
• CylinderSensor User clicks and drags to rotate
  an object around its Y (up-down) axis
• SphereSensor User clicks and drags to rotate
  an object freely around all axes
• ProximitySensor Event is triggered when user
  enters a specified zone
• VisibilitySensor Event is triggered when object
  enters or exits the user's view
• TimeSensor When activated by one of the
  above sensors or a script the
• TimeSensor outputs the
  absolute time plus fractional values
• between 0.0 and 1.0 for a
  specified duration. It is used to "drive"
• animation interpolators.
• Collision Not technically a sensor at
  all but a special grouping node. It
• does, however, generate
  output events when the user collides
• with the group so it is worth
  mentioning with the other sensors.

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Scripting

• Required when-
• keeping track of an object's state (eg. is the
  door open or closed?)
• when the interactions of one object are
  conditional on the state of another (IF ...
• THEN ... ELSE type statements etc)
• any time mathematics is required (eg. PI or
  random number generation or sine wave animation
  path etc)
• runtime creation of custom nodes (eg. build me a
  spiral staircase 3 metres high etc)

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Switch Nodes

• Allows the same Node in the scene graph to switch
  between different groups
• Possible uses
• Changing fabrics for dress model
• Changing items on shelf
• Switching between open and closed door

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Navigation and User Interface

• Specify Method(s) of Navigation
• Create Viewpoints
• Hyperlinks and HUD (Head Up Display)

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Specify Method(s) of Navigation

• NavigationInfo Node
• Camera
• Avatar (see later Lecture) - also congigurable
• Navigation Style
• Walk User affected by gravity
• Fly No gravity
• Examine Rotate scene around
• None No navigation controls - good for banner
  ads or if you are creating your own controls
• Any User may choose any navigation they wish

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Viewpoints

• Allows several specialist views to easily
  navigate
• Can be linked to sensors attached to objects

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Hyperlinks and HUD

• Hyperlinks - any object can be linked to a URL
• A HUD (Head Up Display) is a construct of
• a number of VRML nodes and a ProximitySensor
• The ProximitySensor basically keeps track of
  where the user is and feeds the groups position
  and rotation into the group of objects that
  comprise the HUD to keep it positioned just in
  front of them at all times.

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Packaging And Web Integration

• Stores all files into one directory so that they
  can be easily published
• An initial link to the .wrl file must be
  incorporated into the start-up page
• Provided any separate files are in the same
  directory the seperatae .wrl files can be inlined
  or hyperlinked at will

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Optimise and Test (General Guidelines)

• Reduce the polygon count
• Reduce detail
• Build only what will be seen
• Modularity
• Scale
• Create Levels of Detail (LODs)
• Materials and Texturing

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Publish

• FTP to Host
• Keep same file structure