Fun Kinection

<Play Test Video>

Play Test Video

After several play testing, we found out something interesting. Many people tried to punch to the side because they feel that the ninjas are passing by. The game didn’t work really well  because of that. So, we changed the punch mechanic.

The First apporach was based on Velocity Statemachine. When there is a spike on velocity, we checked the Wrist position and the distance from the shoulder, based on the thresholds the punches are confirmed.

The problem with this apraoch is was players other movements caused spike in the velocity and false punches declared.Added to that there were lot of false possitves when we measure the distance and the axis.

The second apprach was Colliders. We had plane colliders before players and we were checking the collision of wrist and velocity to declare the punches.We enhanced this by using a curved half capsule to cover all the angled punches.

The issue with this approach is when there is a rapid collision – that is when the users does a fast punch, the collision was nt detected becuase of the rate in which kinect gives Skeletal data and unity update/Fixed update cycle rate wasnt in sync.

Third approach is Raycasting on a collider. Since collision approach failed we used raycasting,Wrist distance from shoulders and velocity as parameters to declare punches.This approach helped to increase the detection accuracy far better.

Head Tracking is…

The images on the screen change by the Kinect sensor camera tracking the location of player’s head. This technology transforms the display into a portal to a virtual environment. The display reacts to head movement as if it were a real window creating a realistic illusion of depth and space.

To understand this concept better, here is an example of head tracking in a video by Johnny Lee. He is using a Nintendo Wii remote. Instead of holding it in his hand, he put the Wii remote in front of the TV and moved the sensor bar. He then mounted the sensor bar on a hat to let it track his head. This is the opposite way of the intended functionality of this technology, but it is only through this clever use that head tracking – or the”Perspective 3D” effect – is gained.

<Johnny Lee Video – Head Tracking with Wii Remote>

BUT, Kinect doesn’t need any controller because YOU ARE THE CONTROLLER! 🙂 Kinect can track the skeleton so it already knows where your head is without a device mounted hat.

<Head Tracking with Kinect>

<User Interface Design>

We wanted to design the User Interface to be smooth and easy for players to navigate . Since we are using head tracking technology we need to know the size of television because that will influence how far the player can lean and dodge to find the weak spots. We needed to keep in mind that with stereoscopic 3D, 2D UI assets wouldn’t work the way we wanted, so we needed to change the cameras every time the game pauses for a menu. UGC (user generated content) is one of the pillars of Fun Labs, so we combined UGC, the scoreboard, and a local leaderboard, so that player can see their picture and where they stand compared to other players.

We needed a UI screen to warn the player that the Kinect sensor could no longer see them, so we implemented this screen. When the player is back in view, we have the player do the same action (punch) to resume the game as they did to start the game instead of using buttons and hand cursor with loading bar. Loading bars are boring, even though we have a cute hand cursor 🙂

Nobody wants to mess with NINJAS! Ever since we decided to make our game with a ninja theme, we had a clear concept about the art. But, there were some changes as the game design changed a bit by bit.

<Initial Sketch>

Here is a quick sketch for the character by our awesome 3D artist Wai Kay. We removed red scarf later, but that was a good start.

<Mood Board>

We made this mood board at the very beginning  for a clear design direction. We wanted our ninja to look cool and sleek! This is a glimpse into my thought process. We started with a concept of what our ninja would be like. He would be all black with a sword; an assassin who lurks in the shadows and appears and disappears via smoke. 🙂 So, our design ended up with strong color and light contrast.  Black and red were our theme colors, but the environment color shifted with playtesting as we decided to change the level’s color to indicate progression and difficulty.

<Concept Art>

Our game environment is a Dojo house. Why a Dojo house? Of course, it fits the theme, but it also naturally enhances the 3D perspective view which is really important for our core game play mechanic – head tracking. You can see for yourself how this works in our post, ‘here’.

Ninjas charge down the infinite hallway and player needs to find the green spot (weak spot) by dodging and leaning to punch it. We stylized the weak spot as a sigil on the waist band with a brush stroke cross hair. Since the environment is little dark because of intended shadows, we made weak point bright green to catch player’s attention.