skyra.github.com

Skyra Elements

2017-08-13T00:00:00+00:00

I’m starting to work on the beginning of a tool to help make controling diy IOT devices with google home a possibility. To control lights, I have emuluated a Phillips Hue hub, but it’s very limiting. I’d like a way to build any device that google can potentially control (lights, thermostats, switches, outlets, scenes) and then just control it. Google requires you jump through a few hurdles like authentication in order to do it. I’m starting to work on Skyra Elements which is a combination of firebase functions and auth that should simplify the process of connecting devices to google home. More to come!

Bird

2014-05-20T00:00:00+00:00

Rubik's cube moment

2014-04-10T00:00:00+00:00

Just some pictures from my Narrative Clip

Random Pictures

2014-03-16T00:00:00+00:00

OSCeletonWrapper

2013-09-22T00:00:00+00:00

Getting Started

OSCeletonWrapper is a processing library which wraps OSCeleton and makes it easy to use Skeleton data inside processing. The easiest way to install OSCeletonWrapper is clone the repo into the processing library directory. The user library directory is inside the libraries folder in your sketch directory. Use this command to clone the repo:

git clone https://github.com/cketcham/OSCeletonWrapper

or download a zip file from here: https://github.com/cketcham/OSCeletonWrapper/archive/master.zip

Examples

In order to use this library with your kinect, you will need OSCeleton set up and sending messages. Information on how to get everything working can be found here: How to get Kinect Data into Processing.

Two examples are included with this library

More information about both can be found here:

What a great first day at Maker Faire!

2013-09-21T00:00:00+00:00

If you stopped by today, glad to see you! If you haven’t been by yet, come check us out in Zone A in the Viscusi Gallery. If you are looking for the source for the demos, I’ll post more info soon, so stay tuned…

Maker Faire NYC This Weekend

2013-09-15T00:00:00+00:00

I’m excited to show what I’ve done with the kinect and help other learn how to do it to. I’ll update here with information about how to find my booth. Hope to see you there!

_three.js playGnd

2013-08-23T00:00:00+00:00

http://threejsplaygnd.brangerbriz.net/gui/

It’s a cool way to play around with webGL and actually create something using a combination of programming and playing with sliders and options.

here is what I made: http://threejsplaygnd.brangerbriz.net/s/?id=128

Smoke Clouds

2013-08-22T00:00:00+00:00

Maker Faire NYC: Hacking the Kinect for artistic projects

2013-08-06T00:00:00+00:00

I’m proud to say that I was accepted to showcase my work at Maker Faire in NYC from September 20th to the 22nd at the New York Hall of Science in Queens.

Come visit me! As my title says, I will be showing the tools and libraries I use to play with the kinect. I will also be showing the pieces I have created such as Life as a Tree and Kinect Force, as well as a few new things I have been working on. Buy tickets here (Let me know if you are planning on going, I can probably get you a discounted ticket). I hope to see you there!

Life of a Tree

2013-04-05T00:00:00+00:00

This is my second piece for Bushwick First Friday. The theme Awakening, was inspired by the coming of Spring.

Here are the previous blog posts related to this piece if you are interested in reading them

Hopefully you came and had a chance to play with it!

I also took a few video clips and put them together to make a short video.

Kinect Force

2013-04-03T00:00:00+00:00

Building upon my last post about Kinect and Processing, I decided it would be fun to add some particle systems to a sketch that could be controlled by the user’s skeleton. I ended up picking toxiclibs.org since it seemed to be the most fully featured library for using physics and having particles interact.

I set up a simple particle system with various forces and added some attraction to the hands. This was the result.

If you are interested in trying it out yourself, get the OSCeletonWrapper processing library and the code for this example here: https://github.com/cketcham/kinect_force

HTML5 apps vs Native Apps

2013-03-22T00:00:00+00:00

I’ve always felt a struggle between HTML5 apps, and native apps. There are many great apps which are written with HTML5 which use Cordova, jQuery Mobile, or just something like Boostrap. And there are equally great apps which were built for native phone clients. I think overall the choice of whether to write an app with HTML5 or to write a native app really depends on the app you want to write. But ignoring that, this is what I think about the HTML5 vs. native debate.

I’m an native android programmer so that probably plays into my bias, but I don’t think an application written with HTML5 (the way we do now) can ever be as good as native applications since you can’t take advantage of the design patterns for specific devices easily. And if you decide to invest the time to create a different experience for each device, you might as well have just built a native app in the first place!

I think it really comes down to the amount of time you can put into an app. HTML5 is nice since you don’t need to put as much time into it since it will work on multiple devices. But since you don’t put as much time into the app, it won’t be as polished as it could be if you had spent the time making one app per device.

I think eventually another layer will be created that can create easily customizable interfaces on an individual level. There is less of a linkage between how the server and the clients behave since they can communicate using JSON messages or something similar. So multiple different clients can use the same server api to get the data. The problem is that the visualization is usually all on the client.

Imagine there was another layer in between the data from the server and the client ui. It’s a very similar idea to the way atom xml works for blogs. If you have an rss reader, you can read data from websites and blogs and it can be formatted any way the user wants since the xml specifies the structure of the data to be viewed, but the reader specifies how the ui should look. If there was something similar for apps, you could have a general device like and iPhone or Android or a desktop that would read data from an app, but it would automatically be formatted in a consistent way depending on the device. So as an app developer you would only have to develop the middle layer. You could take data from existing servers (or create new servers if you needed to) and format it in this universal app layer. Then device manufacturers (or the end user) would build in readers to the devices themselves which could handle any app written in this universal app layer.

Although maybe this isn’t possible though since applications can be so different.. unlike blog posts.

And maybe HTML5 will become this eventually. HTML5 has the capabilities to access different features of phones. All that is needed, is an app/reader/browser which will render the pages with native ui components and design.

How to setup Microsoft Kinect on OS X 10.10 with Processing

2013-03-17T00:00:00+00:00

The Kinect is an awesome tool to get skeleton data. Processing is an awesome tool for creating visualizations. Combined they can be used to make cool interactive visualizations.

Since OpenNI has been taken down, the best source I’ve found for setting up the kinect is here: http://blog.nelga.com/setup-microsoft-kinect-on-mac-os-x-10-9-mavericks/

Once everything is installed, you can use OSCeleton to send OSC messages to processing.

You can use OSCeletonWrapper to help read those messages in processing.

more info here

Seed Animation

2013-03-15T00:00:00+00:00

I tried an animation workflow.. I knew animation was difficult, but I have a newfound respect for animators everywhere. Enjoy my first attempt at an animation!

Tree Generation in Processing

2013-03-10T00:00:00+00:00

I’m working on a processing sketch which generates trees of different heights randomly. I started from this sketch: http://www.openprocessing.org/sketch/2235. I like the way it looks, but I want something that will grow and is animatable.

Let’s start from the main sketch code.

Tree tree = new Tree();
 
void setup() {
  size(1024, 640, P2D);
  colorMode(RGB, 255);
  background(192);
  smooth(8);
}
 
void draw() {
}
 
void keyReleased() {
  background(192);
}
 
void mouseReleased() {
  tree = new Tree(mouseX, height, height-mouseY, 5);
  tree.render();
}

Since I want the sketch to be animatable, I need to set the rendering engine to P2D. Using this rendering engine leaves the lines a little jagged, so I also set the smoothness to 8 with smooth(8). I also think the size of the drawing is a little small so I increase the size to 1024x640 so it’s twice as big.

The way the drawing code works is that each time the mouse is clicked, a new tree is created and drawn to the screen. No other operations are done in the drawing loop. Since I want to be able to animate the motion of the tree, I have to be able to continuously draw the tree each frame, so I need to move the call tree.render() into the draw() function.

void draw() {
  background(192);
  tree.render();
}

This makes it redraw the tree each time, but it is madness! Each frame, it will draw a new tree (with branches in different places) at the same x position on the screen. At 60 frames a second that is a lot of trees thrashing about! To prevent the code from generating a new random tree each frame, I need to use randomSeed(). By setting a seed, I am ensuring each successive call to random() will return random numbers in the same order. Here is the code for the tree which draws each frame using the same random numbers:

class Tree {
  float x, y;
  float h;
  float steps;
  int seed;
   
  Tree() {
    x = 0;
    y = 0;
    h = 0;
    steps = 0;
    seed = int(random(0, 1000));
  }
   
  Tree(int x_, int y_, int h_, int s_) {
    x = x_;
    y = y_;
    h = map(h_, 0, height, 0, 160);
    steps = s_;
    seed = int(random(0, 1000));
  }
   
  void render() {
    randomSeed(seed);
    stroke(32);
    branch(x, y, -HALF_PI, h);
  }
   
  void branch(float x_, float y_, float a_, float s_) {
    strokeWeight(s_/16);
    float a = random(-PI/16, PI/16)+a_;
    float nx = cos(a)*s_+x_;
    float ny = sin(a)*s_+y_;
    stroke(32, 16*s_);
    line(x_, y_, nx, ny);
    if (s_>10) {
      branch(nx, ny, a_-random(PI/4), s_*random(0.6, 0.8));
      branch(nx, ny, a_, s_*random(0.6, 0.8));
      branch(nx, ny, a_+random(PI/4), s_*random(0.6, 0.8));
    } else {
      float w = random(155, 255);
      stroke(255, w, w, random(32, 192));
      strokeWeight(random(0, 8));
      point(nx+random(-2, 2), ny+random(-2, 2));
    }
  }
}

Ok cool, but I also want to be able to make the tree grow. For now I will link it to the vertical movement of the mouse. I can just change the height of the tree h in the render() function based on the mouseY variable. Here is the new function:

void render() {
  randomSeed(seed);
  h = map(height-mouseY, 0, height, 0, 170);
  stroke(32);
  branch(x, y, -HALF_PI, h);
}

Uh oh. It almost works. When the mouse is not moving the same tree draws every frame, but when I move the mouse up and down to change the height of the tree, the branches move. Not what I want. This is caused because the tree is being drawn using recursion, i.e. depth first using the program stack. This means it draws the trunk, then draws the first branch, then draws that branches first branch all the way down to a leaf. Then it goes back up one step and draws the next leaf. Learn more about Depth First Search on Wikipedia! Since the order of the random calls is set using randomSeed() when it draws a bigger tree, the calls to random() on the smaller tree no longer apply to the same branches to the bigger tree, since it adds branches in the middle. I can fix this by changing the order of branch drawing to Breadth First. This will ensure that the random calls always apply to the same branches. Breadth first will draw the trunk, all of is branches, all of the branches’ branches, etc until it gets to the final branches and all the leaves.

That brings me to the final code which I am going to use for now.

treeSketch.pde

Tree tree;
 
void setup() {
  size(1024, 640, P2D);
  colorMode(RGB, 255);
  background(192);
  smooth(8);
}
 
void draw() {
    background(192);
    if(tree != null)
      tree.render();
    frame.setTitle(frameRate + "fps");
}
 
void keyReleased() {
}
 
void mouseReleased() {
  tree = new Tree(mouseX, height, height-mouseY, 5);
}

Tree.pde

class Tree {
  float x, y;
  float h;
  float steps;

  int seed;


  Tree() {
    x = 0;
    y = 0;
    h = 0;
    steps = 0;
    seed = int(random(0, 1000));
  }

  Tree(int x_, int y_, int h_, int s_) {
    x = x_;
    y = y_;
    h = map(h_, 0, height, 0, 160);
    steps = s_;
    seed = int(random(0, 1000));
  }

  void render() {
    randomSeed(seed);
    
    h = map(height-mouseY, 0, height, 0, 170);
    print(h + "\n");

    stroke(32);
    branch(x, y, -HALF_PI, h);
  }

  void branch(float x_, float y_, float a_, float s_) {

    branches.add(new Branch(x_, y_, a_, s_));

    while(branches.size() > 0) {
      
      Branch b = branches.get(0);
      branches.remove(0);
      
      strokeWeight(b.s/16);
      float a = random(-PI/16, PI/16)+b.a;
      float nx = cos(a)*b.s+b.x;
      float ny = sin(a)*b.s+b.y;
      stroke(32, 16*b.s);
        line(b.x, b.y, nx, ny);
  
      if (b.s>10) {
        branches.add(new Branch(nx, ny, b.a-random(PI/4), b.s*random(0.6, 0.8)));
        branches.add(new Branch(nx, ny, b.a, b.s*random(0.6, 0.8)));
        branches.add(new Branch(nx, ny, b.a+random(PI/4), b.s*random(0.6, 0.8)));
      } 
      else {
        float w = random(155, 255);
        stroke(255, w, w, random(32, 192));
        strokeWeight(random(0, 8));
        float offx = random(-2, 2);
        float offy = random(-2, 2);
        point(nx+offx, ny+offy);
      }
    }
  }
  
  class Branch {
     float x, y, a, s;
     public Branch(float x_, float y_, float a_, float s_) {
       x = x_;
       y = y_;
       a = a_;
       s = s_;
     }
  }

  ArrayList<Branch> branches = new ArrayList<Branch> ();
}

The last thing I need to fix is the drawing of the blossoms since they are constantly jumping around. This is caused by the same problem I experienced when drawing the branches. I could just set another random seed before I draw the leaves to ensure they are always drawn the same way like the branches are. But for now I like what I’ve done.

Live 9 release event

2013-03-07T00:00:00+00:00

I have used Ableton Live for a while to produce music and I really like it. The flow for building song structures, adding effects, and playing with controllers is very smooth and natural. Although the instruments provided by Live are a little lacking in functionality and depth, I love to use Live to play different VSTs or Reason (as an external instrument). Nothing else compares to Live for controlling audio or midi streams and adding effects. Here is a little intro video to live if you don’t know anything about it.

I went to the preview event of Live 9 and Push (a controller built for Live 9) at Tekserve in NYC on March 5th. They were really trying to promote the Push controller as an instrument, saying you don’t even need to look at the computer to make entire songs. They had a few good performers who demonstrated the functionality of the device and I’d say I agree for the most part. I still think final editing and mastering will be easier to do in Live on your laptop, but being able to create ideas and just flow from one thing to the next is an invaluable tool offered by the device. I wonder if it will be possible to configure different midi hardware to take advantage of some of the new features in Live 9 which make the Push so appealing.

The push adds many features although two of them caught my eye and seem like they would be fun to play with. One is the ability to add notes to a clip of different lengths easily using the top half of the 64x64 grid in the same way you would program a drum machine. The second feature is the ability to easily browse to different key signatures to play notes. Both of these additions are nothing new as people have written programs for the monome which do the same thing. The main difference is the level of integration with Live is much better.

Humble Bundle 5

2013-03-05T00:00:00+00:00

I really love the humble bundle downloads. Especially the releases they have for Android. You can pay what you want and they are always worth what you pay. I haven’t even gotten past the first game that I downloaded, Super Hexagon. You move the triangle between the edges in different styles of levels. Its such a simple game, but it is extremely fun and challenging.

Here is a quick trailer for the other games included in the bundle. Most of them look pretty fun!

Mouse On Mars

2013-03-02T00:00:00+00:00

I haven’t listened to Mouse on Mars in ages, but they used to be one of my favorite bands. Mouse on Mars is a duo based out of Germany made up of Jan St. Werner and Andi Toma. They have been making electronic music since 1993. I was first introduced to them by an electronic music teacher I had while I was in high school. I instantly fell in love with the glitchy electronic sound they create. Two of my favorite songs are Wipe That Sound and Duul.

I randomly discovered Mouse on Mars would be playing in NYC the morning of the show. Luckily I didn’t have any plans since I have been dying to seem them perform live for quite a long time. I wanted to see them perform the last time they toured the US 6 years ago, but wasn’t able to. Talk about a long wait! The show started out with a set by Soft Circle, a local NYC group, with Hisham Bharoocha and Ben Vida. They had an interesting sound composed mostly of hardware synths and looping effects along with some looped vocals and triggered drums.

Then Mouse on Mars took the stage. They played a lot of new songs which I hadn’t heard yet. I really need to get their new album to take a listen, but based on what I heard during they show, they seem to have merged their glitchy and quirky sound with electro style dance beats. They have always had a knack for integrating weird electronic sounds and effects with a more mainstream pop style.

Its been at least 6 years since I really listened to anything they made, but I really enjoyed the show overall. They had a very electronic feel, sort of like siman mobile disco, but a bit rougher at times. They used a lot of really cool effects and I really loved the vocals. Check out a few more pictures of the show here.

Mouse On Mars (Live)

2013-03-02T00:00:00+00:00

WHY!!?@#!>#?#@

2013-03-01T00:00:00+00:00

Welcome to my piece for Bushwick First Friday. The theme this month was Tangible Absence.

Congratulations! If you followed the QR-code, you found the one component of my display which actually functions correctly! Give yourself a pat on the back. If you have no idea what I’m talking about, this is what it looked like:

####Errors Galore Everything else had some kind of problem or error. Don’t you just hate when that happens? I had phones which couldn’t connect to the internet, find a GPS signal, or just crashed for no reason. I also set up a comment system on a computer which would show the dreaded bsod occasionally. I hope you got a chance to play with them.

####My Idea I started by thinking of the things that have the biggest impact in my life when they are absent. I immediately thought of my phone and computer. I require them to be connected to the things around me. I use Google Maps to get directions. I use Yelp to find places to eat. How did people survive before the internet?

####The Piece In this piece, I tried to show what happens when technology goes wrong. Although technology can be helpful, when it’s not working it makes things even more difficult to deal with. We have become so dependent on our phones that when they break, we are stuck trying to figure out how to fix it before we can move on to the thing we were trying to accomplish in the first place!

I'm in New York

2013-02-02T00:00:00+00:00

I’m in New York! Finally! I just moved here to work on android development at Cornell NYC Tech. I’m part of an awesome team which is developing mobile health software.

I decided to start this blog to help foster collaboration between me and other interested individuals. Check out the Issues to see the kinds of things I’m working on and the kinds of things I want to do. And help me out or work with me on any of them if you find them interesting.

Sutro Baths

2012-12-27T00:00:00+00:00

Battery Park

2012-12-27T00:00:00+00:00

Siyu and I got up really early, drove north of the Golden Gate Bridge, and got a few awesome pictures!