penguin sounds

At my job, we have one of those new espresso pod machines in the kitchen. Usually after lunch, I’ll start to get a little drowsy and need a caffine kick.

Today, I chose the heavy duty espresso forte pod and made myself a double espresso.

After finishing it, I immediately found the puzzling bug that the lead dev and I had been staring at. Super. I then misread the spec and dove deep into Qt4′s QTableView MVC architecture before coming up for air.

There are twothreefour¹ things wrong with caffine.

1. Too much and I get anxious and my heart starts jumping
2. I start thinking too fast and making mistakes
3. I hear you can build up a tolerence, so I’d need more and more to have the same effect
4. The inevitable crash

I try to not have it every day, so I can preserve the wonderful, creative effect it has.²

1. No one expects the Spanish Inquisition! [↩]
2. This post was a result of caffine [↩]

In Ardour, we have numbered audio tracks named Track 1, Track 2, and so on. Most software when faced with what to name the next created track will just use a static int that is incremented with each track.

With Ardour, we wanted to make it smarter. We wanted to be able to re-add Track 1 if the first track was deleted. But not if the first track had just been renamed. We use C++ for the libardour backend, so we were in luck.

The STL includes bitset, a very handy wrapper for what’s essentially an array of booleans, but optimized for space.

The technique is: look for the first false slot in the bitset. The index is the number of the new track. When a track is deleted, mark the slot as false. This lets the user rename a track and it won’t interfere with the counting.

The one problem with this is the size of a bitset is set at compile time. You could use vector<bool>, but its use is discouraged. Luckily, boost.org has an implementation of dynamic_bitset which can be grown during runtime.

This smart counting gives Ardour a polish and the users love it.

I’ve created a boost.framework for those of you lucky enough to be using C++ on OS X. It’s all header files, so you only need to include it in the frameworks path. It doesn’t need to be linked in. It unzips to a large size, but you only pay for what you use.