Temporal Distortion Temporal Distortion Perspective) Perspective) - PDF document

Temporal Contour (from the Blue Player’s Temporal Contour (from the Blue Player’s Temporal Distortion Temporal Distortion Perspective) Perspective) t t Blue view Blue view y y Orange view Orange view x x Properties of the Co- -ordinate System ordinate System Generalizing the Local Temporal Contour Properties of the Co Generalizing the Local Temporal Contour � The co � The co- -ordinate system is defined ordinate system is defined � Each user perceives all collisions � Each user perceives all collisions � � Limitations: Limitations: independently for each player independently for each player correctly correctly � players are capable of moving along a single axis only � players are capable of moving along a single axis only � � Depends on the player’s current Depends on the player’s current � Objects that approach the local � Objects that approach the local position and the delay of arriving position and the delay of arriving user are rendered in the user’s user are rendered in the user’s � supports two � supports two active objects only active objects only information information time time � � Generalization to a 4D Generalization to a 4D co co- -ordinate ordinate system system requires preserving requires preserving � Changes dynamically as the player � Changes dynamically as the player � Smooth movement � Smooth movement for the local user: for the local user: moves or as the network properties moves or as the network properties change change � interacting � interacting naturally with naturally with passive objects passive objects in vicinity in vicinity � � Defines how a passive object Defines how a passive object � seeing � seeing remote interactions remote interactions (passive (passive- -to to- -passive, passive, passive passive- -to to- -active) active) should be rendered should be rendered naturally naturally � � Two interacting objects are Two interacting objects are � perceiving rendered at the same time � perceiving smooth motion of remote objects smooth motion of remote objects rendered at the same time reference point reference point Local Temporal Contour Linear Temporal Contours Local Temporal Contour Linear Temporal Contours � The local user at ( The local user at (0, 0, 0 0, 0, 0) ) d ( ( p p , , r r ) ) � d � Each active object is � Each active object is y y assigned a t t value value assigned a corresponding corresponding to its latency to its latency local local x x � Interpolate � Interpolate the contour the contour over over x p p r r x t t all active objects including all active objects including local local d ( d ( r r , , p p ) ) � Contour defines a suitable � Contour defines a suitable t t value for each spatial point value for each spatial point x p p r r x 1

Multiple Players: Aggregating the Temporal Multiple Players: Aggregating the Temporal 2½- 2½ -Dimensional Temporal Contour Dimensional Temporal Contour Contours Contours d ( ( p p , , s s ) ) d d ( d ( p p , , r r ) ) t t d ( d ( p p , , q q ) ) x x p p r r q q s s y y d ( d ( p p , , s s ) ) d ( ( p p , , r r ) ) d d ( d ( p p , , q q ) ) x x x x p p r r q q s s Worth Noting Problems Worth Noting Problems ⇒ shadows (see the possibly visual disruptions on impact ⇒ � simple linear functions instead of continuous temporal simple linear functions instead of continuous temporal � � possibly visual disruptions on impact shadows (see the � lecture notes for details) lecture notes for details) contours contours � sudden changes in the player’s position or delay can cause sudden changes in the player’s position or delay can cause � � � LPFs are the ‘opposite’ of dead reckoning LPFs are the ‘opposite’ of dead reckoning unwanted effects unwanted effects � no prediction for remote players � no prediction for remote players � if a player leaves the game, what happens to the temporal contou � if a player leaves the game, what happens to the temporal contour? r? � the closer the players get, the more noticeable the temporal the closer the players get, the more noticeable the temporal � � � third party instrusion: someone with a high delay ‘blocks’ the i third party instrusion: someone with a high delay ‘blocks’ the incoming ncoming distortion becomes distortion becomes entities entities � jitter: entities start to bounce back and forth in time � jitter: entities start to bounce back and forth in time � � in critical proximity interaction becomes impossible in critical proximity interaction becomes impossible � � no mêlée no mêlée Bullet Time Bullet Time in Multiplayer Games Bullet Time Bullet Time in Multiplayer Games � � movies: visual effect combining slow motion with dynamic movies: visual effect combining slow motion with dynamic � � two approaches: two approaches: camera movement camera movement � speed up the player � speed up the player � slow down the other players � slow down the other players � computer games: player can slow down the surroundings to � computer games: player can slow down the surroundings to have have more time more time to make decisions to make decisions � if a player can slow down/speed up the time, how it will affect � if a player can slow down/speed up the time, how it will affect the other players? the other players? � � easy in single player games: slow down the game! easy in single player games: slow down the game! � � localize the temporal distortion to the immediate surroundings o localize the temporal distortion to the immediate surroundings of the f the � � how about multiplayer games? how about multiplayer games? player player � � but how to do that? but how to do that? ⇒ local perception filters! ⇒ local perception filters! 2

Adding Bullet Time to LPFs Adding Bullet Time to LPFs p p Shoots Shoots r r Without Bullet Time Without Bullet Time � � player using the bullet time has more time to react player using the bullet time has more time to react d ( d ( p p , , r r ) ) ⇒ ⇒ the delay between bullet the delay between bullet- -timed player and the other players timed player and the other players increases increases � add artificial delay to the temporal contour � add artificial delay to the temporal contour p r x x p r d ( d ( r r , , p p ) ) p x x p r r p p Shoots Shoots r r While While p p Is Using Bullet Time Is Using Bullet Time p Shoots p Shoots r r While While r r Is Using Bullet Time Is Using Bullet Time d ( ( p p , , r r ) ) b ( ( p p ) ) d b b ( b ( p p ) ) p r d d ( ( p p , , r r ) ) p r x x p p r r x x d ( ( r r , , p p ) ) d b b ( ( p p ) ) r r d ( ( r r , , p p ) ) d p p x x b ( ( p p ) ) b p p r r x x Open Questions 2½- 2½ -Dimensional Temporal Contour and Bullet Time Dimensional Temporal Contour and Bullet Time Open Questions � � non non- -linear temporal contours linear temporal contours � how to compute quickly? � how to compute quickly? t t � � noticeable benefits (if any)? noticeable benefits (if any)? � numerical evaluation � numerical evaluation � � measuring the distortion and its effects measuring the distortion and its effects � � practical evaluation practical evaluation y y � how well does it work? � how well does it work? � does it allow new kinds of games? � does it allow new kinds of games? x x 3