Fun with Git

This weekend I reorganize my home source code projects. I have a number of machines, and over the years each one had accumulated several small source- code projects. (Python scripts, toy games, things like that.) I wanted to put these projects under source code control. I also wanted to make sure they were backed-up. Most of these little projects are not ready to be published, so I didn’t want to use one of the many web-based systems for source-code management.

After some research, I decided to use replicated git repositories.

I created a remote git repository on an Internet-facing machine, and then created local git repositories on each of my development machines. Now I can use git push and git pull to keep the repositories synchronized. I use git’s built-in ssh transport, so the only thing I had to do on the Internet-facing- machine was make sure that the git executables were in the non-interactive- ssh-shell’s path. (Which I did by adding them in my .bashrc file.)

Git’s ability to work off-line came in handy this Sunday, as I was attending an elementary-school chess tournament with my son. Our local public schools don’t have open WiFi, so there was no Internet connectivity. But I was able to happily work away using my local git, and later easily push my changes back to the shared repository.

Microsoft New Xbox Experience Avatars

I just tried creating an avatar on Microsoft’s new Xbox dashboard. As you can see (at least when the Microsoft server isn’t being hammered) on the left, they provide a URL for displaying your current Avatar on a web page.

The character creation system is not too bad. In some ways it’s more flexible than Nintendo’s Mii (for example more hair styles and clothing), but in other ways it’s more limited (less control over facial feature placement).

My avatar looks better on the Xbox than it does here – they should consider sharpening the image. For example, the T-shirt my avatar is wearing has a thin-lined Xbox symbol.

I think they do a good job of avoiding the Uncanny Valley effect. I look forward to seeing how avatars end up being used in the Xbox world.

In othe Xbox-related news I’m enjoying playing Banjo Kazooie Nuts & Bolts with my son. All we have right now is the demo, but it’s great fun for anyone who likes building things. It’s replaced Cloning Clyde as my son’s favorite Xbox game.

Internals of the Azul Systems Multi-core Java processor

I’m a big fan of CPU architectures. Here’s a conversation between David Moon formerly of Symbolics Lisp Machines and Cliff Click Jr. of Azule Systems. They discuss details of both the Lisp Machine architecture and Azule’s massively multi-core Java machine.

A Brief Conversation with David Moon

The claim (from both Symbolics and Azule) is that adding just a few instructions to an ordinary RISC instruction set can make GC much faster. With so much code being run in Java these days I wonder if we’ll see similar types of instructions added to mainstream architectures.

Next gen video console speculation suggests we aim low

The next generation of video game consoles should start in 2011. (Give or take a year). It takes about three years to develop a video game console, so work should be ramping up at all three video game manufacturers.

Nintendo’s best course-of-action is pretty clear: Do a slightly souped-up Wii. Perhaps with lots of SD-RAM for downloadable games. Probably with low-end HD resolution graphics. Definately with an improved controller (for example with the recent gyroscope slice built in.)

Sony and Microsoft have to decide whether to aim high or copy Nintendo.

Today a strong rumor has it that Sony is polling developers to see what they think of a PlayStation 4 that is similar to a cost-reduced PlayStation 3 (same Cell, cheaper RAM, cheap launch price.)

Sony PS4 Poll

That makes sense as Sony has had problems this generation due to the high launch cost of the PS3. The drawback of this scheme is that it does nothing to make the PS4 easy to program.

In the last few weeks we’ve seen other rumors that Microsoft’s being courted by Intel to put the Larrabee GPU in the next gen Xbox. I think that if Sony aims low, it’s likely that Microsoft will be foreced to aim low too, which would make a Larrabee GPU unlikely. That makes me sad – in my dreams, I’d love to see an Xbox 4 that used a quad-core x86 CPU and a 16-core Larrabee GPU.

Well, the great thing is that we’ll know for sure, in about 3 years. :-)

Will Smart Phones replace PCs?

That’s the question Dean Kent asks over at Real World Tech’s forums. I replied briefly there, but thought it would make a good blog post as well.

I’m an Android developer, so I’m probably biased, but I think most people in the developed world will have a smart phone eventually, just as most people already have access to a PC and Internet connectivity.

I think the ratio of phone / PC use will vary greatly depending upon the person’s lifestyle. If you’re a city-dwelling 20-something student you’re going to be using your mobile phone a lot more than a 70-something suburban grandpa.

This isn’t because the grandpa’s old fashioned, it’s because the two people live in different environments and have different patterns of work and play.

Will people stop using PCs? Of course not. At least, not most people. There are huge advantages to having a large screen and a decent keyboard and mouse. But I think people will start to think of their phone and their PC as two views on the same thing – the Internet. And that will shape what apps they use on both the phone and the PC.

And this switching will be a strong force towards having people move their data into the Internet cloud, so that they can access their data from whatever device they’re using. This tendency will be strongest with small-sized data that originates in the cloud (like email), but will probably extend to other forms of data over time.

Peter Moore on Xbox

Peter Moore on Xbox

I always liked Peter Moore, and I was sorry when he left Xbox for EA. He’s given a very good interview on his time at Sega and Microsoft. (He ran the Xbox game group at Microsoft before moving on to Electronic Arts.) Lots of insight into the Xbox part of the game industry.

Here he is talking about Rare:

...and you know, Microsoft, we'd had a tough time getting Rare back -
Perfect Dark Zero was a launch title and didn't do as well as Perfect Dark...
but we were trying all kinds of classic Rare stuff and unfortunately I think
the industry had passed Rare by - it's a strong statement but what they were
good at, new consumers didn't care about anymore, and it was tough because
they were trying very hard - Chris and Tim Stamper were still there - to try
and recreate the glory years of Rare, which is the reason Microsoft paid a lot
of money for them and I spent a lot of time getting on a train to Twycross to
meet them. Great people. But their skillsets were from a different time and a
different place and were not applicable in today's market.

Pro tip: Try writing it yourself

Sometimes I need to get a feature into the project I’m working on, but the developer who owns the feature is too busy to implement it. A trick that seems to help unblock things is if I hack up an implementation of the feature myself and work with the owner to refine it.

This is only possible if you have an engineering culture that allows it, but luckily both Google and Microsoft cultures allow this, at least at certain times in the product lifecycle when the tree isn’t frozen.

By implementing the feature myself, I’m (a) reducing risk, as we can see the feature sort of works, (b) making it much easier for the overworked feature owner to help me, as they only have to say “change these 3 things and you’re good to go”, rather than having to take the time to educate me on how to implement the feature, (c) getting a chance to implement the feature exactly the way I want it to work.

Now, I can think of a lot of situations where this approach won’t work: at the end of the schedule where no new features are allowed, in projects where the developer is so overloaded that they can’t spare any cycles to review the code at all, or in projects where people guard the areas they work on.

But I’ve been surprised how well it works. And it’s getting easier to do, as distributed version control systems become more common, and people become more comfortable working with multiple branches and patches.

Tim Sweeney on the Twilight of the GPU

Ars Technica published an excellent interview with Tim Sweeney on the Twilight of the GPU. As the architect of the Unreal Engine series of game engines, Tim has almost certainly been disclosed on all the upcoming GPUs. Curiously he only talks about NVIDIA and Larrabee. Is ATI out of the race?

Anyway, Tim says a lot of sensible things:

  • Graphics APIs at the DX/OpenGL level are much less important than they were in the fixed-function-GPU era.
  • DX9 was the last graphics API that really mattered. Now it’s time to go back to software rasterization.
  • It’s OK if NVIDIA’s next-gen GPU still has fixed-function hardware, as long as it doesn’t get in the way of pure-software rendering. (ff hardware will be useful for getting high performance on legacy games and benchmarks.)
  • Next-gen NVIDIA will be more Larrabee-like than current-gen NVIDIA.
  • Next Gen programming language ought-to-be vectorized C++ for both CPU and GPU.
  • Possibly the GPU and CPU will be the same chip on next-gen consoles.