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Show HN: Paper Programs – Run JavaScript on pieces of paper

235 pointsby janpaul123over 7 years ago

9 comments

janpaul123over 7 years ago
Hi! I was asked to repost this (a la <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=11662380" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=11662380</a>), so here goes. I&#x27;m JP, and I created this project after visiting Dynamicland a couple of times. I wanted to capture some of the magic there in my living room, and decided to implement the &quot;programs running on pieces of paper&quot; part.<p>It was super fun implementing this. I ended up using OpenCV.js, which has only just been released, reimplementing an OpenCV algorithm and learning about computer vision, learning about OffscreenCanvas, which is so experimental that it crashes periodically (a bug I was able to isolate and submit to the Chrome dev team), learning about how to mount a projector facing downward, and so on.<p>Few things are as satisfying as a piece of paper rolling out of a printer literally onto the floor, where it starts executing. And then cutting it up with a pair of scissors to change its shape.<p>I hope you have as much fun with this as I do!!<p>PS: If you want more inspiration for building cool stuff with projectors and cameras, check this out: <a href="http:&#x2F;&#x2F;tangible.media.mit.edu&#x2F;project&#x2F;pico&#x2F;" rel="nofollow">http:&#x2F;&#x2F;tangible.media.mit.edu&#x2F;project&#x2F;pico&#x2F;</a> :) They have a ton more interesting projects like that!
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ChicagoBoy11over 7 years ago
I work in an elementary school and I&#x27;m trying hard to think about how to possibly take advantage of this in my environment. The interaction model is really rich and perfect for the children, but I&#x27;m so far coming up empty on the sorts of things we could&#x2F;should do with it.
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camtarnover 7 years ago
Very interesting interaction model. I love the idea of a program being able to read the shape of the paper - lots of cool possibilities.<p>However - slightly disappointed that the programs are not literally controlled by symbols on the pieces of paper, but rather the paper just holds identifiers who point to a program on a server.<p>I wonder if you could extend the computer vision system to pick up actual programs from the paper - either by OCRing actual text (perhaps limited to capital letters only, and&#x2F;or particular shapes for letters such as I-for-India, to make it easier?) or a combination of symbols (each corresponding to a function in the API) and numbers (parameters).<p>That way you could do really interesting things: modifying somebody&#x27;s program by literally pasting a scrap of paper on it containing different symbols or parameters, or having programs which interact with other programs (either by treating their program code as input data, or by piping data between the programs).<p>On the other hand, it&#x27;s probably easier to write interesting programs with an actual keyboard :)
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osrecover 7 years ago
Are the dots essentially a &quot;barcode&quot; that map to a particular program on the server? How does the projector factor in? Do you adjust the projected image to ensure the result falls in the respective paper&#x27;s area? Interesting project - did you have a use case in mind for it?
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throwaway2016aover 7 years ago
This is awesome work. Great job.<p>Dynamicland looks awesome. I wish I could visit. I both live on the wrong coast and it doesn&#x27;t seem to be open to the public yet.<p>One fascinating aspect I found on this project was compiling OpenCV[1] to web assembly. I find it difficult and frustrating to compile OpenCV for my Mac never-mind compiling it to web assembly and running it in a browser. I love the idea of doing that, I&#x27;ll have to try it.<p>[1] Open Computer Vision to save a few people a google
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seanmcdirmidover 7 years ago
Wondering if this could be done with AR (e.g. Hololens or Glass)?
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theon144over 7 years ago
Yes!<p>I&#x27;ve been similarly enchanted when I first saw Dynamicland (well, on twitter, the actual place being on a different continent) and I&#x27;ve actually started my own experiments (but never finished them :( ). Glad to see someone follow through, I&#x27;m definitely going to be watching you closely!
nestorherreover 7 years ago
One of the coolest things I&#x27;ve seen in a while. GJ!
Outpoxover 7 years ago
Really interesting, thanks for sharing!