Indoor positioning system

Recently I read some ML tutorials, and found Google can now determine where the photo was taken [1] without using the GPS metadata. That makes think about indoor positioning.

Imagine when you are lost, you turn on the camera of your cellphone, Google can relaize where you are, and can suggest you direction by AR. This way we don’t need any beacon or physical tags.

I am quite exicited with this idea!

A kiss

Last night, I lied next to my son on the bed, and thought he fall asleep already, so I sat up and wathced his face. Then he pushed himself up, gave me a kiss, and back to sleep. Without a word.

I melt.

I want to stamp that image in my brain, forever. He will soon never do that to me again, he’s growing up, and I’m getting old.

He is now 30 months old, sometimes an angel and sometimes a devil.

Career path

I just read Career advice for engineers, and there’s one piece very impressed me:

I don’t do any career goals or anything like that. I try and do things that are a) interesting to me and b) that the world needs.

To me a) is easy, but b) is not. What do we need actually? Is it another IM, a faster browser, or a nuclear fusion reactor? I guess it is the reactor, it’s something not every people think about but we humanity are going to need to move further.

Indoor automatic drone

While my colleagues were playing a quadcopter in the office today, I was thinking it should be fun if it can delivery things in the office, automatically, like what Google and Amazon are trying to do at outdoor. I’d be happy seeing a machine fly around the office and do job automatically, like a smart toy. That requires an indoor gps and somehow figure out the path for delivering.

Maybe it can also be a security guard, with video recording.

I just came up two more ideas on the way to the office this morning:

1. Explore a new space by its own
   Back in school days, when I played RPG games, entering a map is usually all dark and I need to walk around to figure out what the space is like and found different NPC to interact. That seems the same situation for the drone, so if it can fly around and draws the indoor map automatically, wow, that’s nice and very much easier.
   Edit: I just found Tango seems is doing the same thing, cool, put that on the drone!
2. People can set its waypoint
   Now people can set waypoints on the map. Just like drag and drop the waypoint on a pad and the drone will fly there. Maybe use an IR points to the waypoint, or plot some virtual line in drone’s sight (AR for the drone).

Sounds interesting, I like this toy!

Service worker?

I’ve spent an afternoon to understand what is service worker for bug 1145498, and I found it’s not only a worker, it’s also a proxy between client and server!

Some notes after reading this introduction:

• External events: “install”, “fetch”, “message”, and “activate”
  Fetch is the one which makes it a proxy, service worker will receive fetch events for everything on its registered location. Which it can leverage cache API to keep a local response.
• Works only for https
  Can only register for service workers on pages served over HTTPS since you don’t want any pieice of code can do strange things to your request.
• Can access IndexedDB API
• Possible overhead
  1. IPC
  2. Accessing cache
  3. Cloning request/response