Which of Flanagan’s propositions are the most aligned with your own goals, and why?

I think the third proposition is most aligned with my goals. The first two propositions suggests that the content of games can be critical to encourage players to think critically about issues presented in it. I think these properties are more or less not unique to games. One can also create movies, writings, images to similar effects. So even though game / interactive art is a very good medium for these kind of criticality, and these criticality are very interesting and important themselves, I’m more interested in the third proposal in comparison.

The third proposal deals with new kinds of play. The entire mode of interaction can be different. Each instance is almost like a new medium. For me I find the notion of “new” very central to me when I think about projects I want to make. I think it is what makes me excited about anything.


Matter.js + Webcam Hand Tracking: Real Hand Puppeteering

This project allows users to puppeteer a rag doll with their real hands in their browsers through gesturing in front of webcam. (

^ an animated GIF showing a play session

I came up with the idea since it appears to me that human body tracking and physic engines combines well. Maybe it’s because we always wanted touch and feel objects.

I never learned to puppeteer in real life. I thought rag doll physics might simulate it well, so it’s also a chance to try out puppeteering virtually.

Hand tracking has been around for a long time, but I want to make a new tracker in js for the browser so everyone can play without acquiring hardware or software.

I used matter.js for the physics engine, mainly because I wanted to try something new. But in retrospect, maybe box2d.js would have worked better. However, matter.js seem to have an easier API compared to box2d.js’s automatically ported C-style code.

^ screenshot showing debug screen and camera view.

Custom Software for Hand Tracking in the Browser

Demo of finger tracking available on Glitch:

^ Screenshot showing detection and tracking of multiple hands and fingers

OpenCV.js is used to write all the computer vision algorithms. I used HSV ranges, convex hulls etc. to find fingers in web cam image.


  • Face and hands of the same person have at least somewhat similar color
  • Background is not exactly same color as skin
  • Person relatively near the camera, and their face is visible
  • Person is not totally naked
  • Person not wearing gloves or have stuff over their faces

I’ve worked with OpenCV in C++ and python, but haven’t used the JavaScript port. So this time I gave it a try. I think the speed is actually OK, and API is almost the same as in C++.

^ Testing algorithm before different backgrounds and lighting situations to make sure it is robust.


I think the result is quite fun, but I’m most bothered by matter.js’s rag doll simulation (which I based on their official demo). Sometimes the rag dolls fly away for no apparent reason. One probability is that I’m missing something in the parameters that I need to tweak.

Another problem is that hand tracking is lowering the FPS a lot. When there’s either only physics or only hand tracking, it’s pretty smooth, but when there’s both, things started to get slow.

In terms of puppeteering, I was only able to make the puppet jerk its arm or move a leg. There’s no complex movements such as walking, punching, etc. But I think it’s still interesting to experiment with.

In the future I can also add other types of interactions to the system, for example shooting stuff from fingers, grabbing/pushing objects, etc.

Video Documentation