New to Beyond Casual? – start from part 1!

Part 2 : POV and basic scenes

Point Of View

It is quite common to use terms taken form spoken language and storytelling as a metaphor for the game camera point of view. 1st person shooters put you in the eyes of the character seeing your virtual hands or weapon on the bottom of the screen. In 3rd person games you see your avatar from behind. I usually use the term 2nd person experience to looking at the front side of your character – in a mirror like visualization.

At first 3rd person looks like an easy direction for our gesture games (Especially if you consider the ‘On-Body’ ideas presented in the previous post) However –if your interaction also involve side facing interaction, 
3rd person POV involved fundamental difficulties I didn’t anticipate.

If you assume the tracking system is based on data collected from a front mounted camera (such as the Kinect and the most frequent installation of the PrimeSense sensor). It means the best tracked limbs will be those closer to the TV set. The leg and arm that are far from the set have high probability to suffer from occlusion. Naturally – the tracking of occluded limbs is less accurate – and highly depends on statistical pose models.

Let’s go back to the POV question – a 3rd person representation will show the user the back side of his avatar. When side facing – the occluded limb will be the most visible one – and will draw most of the attention. This fundamental effect is sometimes so strong that most players will think something is wrong with the tracking algorithms.

In 2nd person / mirror view, the non-occluded limbs are the one also most visible to the user. The occluded limb inaccuracy is easier to forgive, as it also seems occluded in the avatar’s rendering.
I am not claiming at all that we should avoid 3rd person completely – merely pointing out on the challenges involved, and the considerations one should be aware of from the game design phase.

Some historical examples for 1st and 3rd person views:
1st person history: 3D Monster Maze (1981)

1st person shooters history: Wolfenstein 3D (1992)

3rd person history: Tomb Raider 1996

Simple game scenes

When people ask how you naturally walk forward in a gesture game, I usually warn of the possibility of hitting the TV set. Navigation is one of biggest challenges for 3D games in general – not only gesture games. Regardless of the chosen paradigm; walking in a 3D virtual world, represented on our 2D displays may be a very frustrating experience: you it’s hard to get a good sense on the depth of the rendered items and scene walls. This is also why so much 3D platform games sucks. Jumping to a higher platform and realizing it is too far only after falling to a lake of lava is not an enjoyable experience! At the end – only extremely talented level editors manage to create fun 3D platformers. For this blog – let’s get lazy this time, and postpone the navigation challenge to future posts…
Rail game

Actually – there are many fun experiences you can create without actually dealing with the navigation problems:
  • Static camera shooting games  where enemies pop out behind cover, or come closer to the avatar to practice some martial art.
  • On-the-rails’ shooters – where the camera motion is predefined. Camera can stop when reaching enemies or when the avatar is behind a cover and continue when level is cleared
  • 2nd person martial arts and melee combat
  • 2nd person dancing game

Some historical examples for static scene + on the rails:

Static camera shooters history: Prohibition (1987)

Static camera shooters history:  Operation Wolf (1987)
Rails history: Operation Thunderbolt (1988)
Rails History: House Of The Dead
In AngryBotsNI – we tried to play with different POV schemes:
  •  You begin in 2nd person ‘get to know your avatar’
  • Once you learn how to teleport you can jump to different scenes or levels
  •  Each level has different POV, so you can experience also 3rd person view

AngryBotsNI 3rd person view
AngryBotsNI 2nd person view

1 comment:

  1. Hi. I can't find AngryBotsNI anywhere. The OpenNI Arena link doesn't work. Could you please provide an alternate download link?