Linux Brain Games

These involve the mind in some way... I like to do Blinken and Gnomine.

Chess. These engines are way too hard for me.

1. Gnuchess
2. Crafty
   

Memory

1. Blinken

Quick Thinking

1. Gnomine
2. KSirtet
3. Tetravex
4. Gnome Sudoku

Uncategorized

1. gtans (Tangrams)
2. Code Breaker / Gnomermind (Mastermind clones)
3. Klotski/Gnome Klotski

Free Online

1. Happy Neuron free games
2. MyBrainTrainer has a test and one free puzzle every month
   

Commercial

1. The Amazing Brain Train (has a demo)
   

I Love Evince!

Evince, the Gnome document viewer under Ubuntu 7.10 and up, is simply a great piece of software. It has some simple features which enhance its usefulness for academic work.

Incremental search instead of boring-old-search make evince my favourite viewer for almost any type of document it supports.

The extra feature I use most often is "Open a Copy" in the File menu. This opens up another instance of evince displaying the same file, very useful when you need several different pages of the document open at the same time.

Another useful related feature is, if you click using the middle button while following a PDF link, the link opens up in a new window (just like in Firefox). That way you don't lose the original page.

Of course, evince could be made better. Here's my wish-list:

1. Add a cycle-through-bookmarks feature for the cases when I want quick browsing in one window instead of many
2. Add an "Open a Copy" toolbar button
   
3. The version of evince I'm using on Ubuntu 7.10 doesn't work at all with the print server CUPS; maybe this is already fixed in the newer versions
4. DVI files are blurred (or maybe over-antialiased)
5. We need browser-style back and forward buttons in addition to the page back and page forward buttons, so we can follow links more easily
6. Would be nice to be able to place two arbitrary (not just adjacent) pages side-by-side.
   
7. Alternatively, allow left-right split window with synchronized scrolling made possible (i.e. scrolling one scrolls the other by the same amount)
8. Add a "search for full word only" option to the incremental search
   
9. More when I think of it!

Whizzytex on Ubuntu 7.10

Whizzytex is a pretty nifty application that updates a compiled TeX pane in real-time as you type into emacs. Under Ubuntu 7.10 it comes as a package in the repositories.

With my installation (on a Thinkpad t61) I've had an annoying problem: every few seconds, emacs will freeze completely for a 1-5 seconds (presumably doing a slice compilation or some such thing for whizzytex). This can happen right in the middle of a yank, and it can happen ten times a minute.

Here's my solution, though I can't explain why it works: put the line

(setq whizzy-load-factor 10)

in your .emacs file. The problem still occurs but very occasionally (once in 5-6 minutes, which I can live with). Whizzy is a lot more responsive now as well.

There is one downside: this really increases processor usage. My laptop runs hot and the battery doesn't last long when I have the load factor set high this way.

Backup (Part II)

I listed some requirements that I have for backup software for a single workstation in an earlier post. I seem to have found a solution that has many of those properties, though not all. It is called SBackup (for Simple Backup) and I am running it on Ubuntu 7.10. (I won't be shifting to 8.04 until all the kinks are worked out, or they invent hibernate for Linux.) It really is simple and runs very well in my situation.

Here's how SBackup satisfies my requirements:

1. SBackup has a modicum of network awareness; it can backup over an SSH or FTP connection in addition to a local directory.
2. SBackup can do incremental and full backups. By default every backup (except the first) in SBackup is an incremental backup. The administrator can specify a schedule for full backups, such as a full backup every 21 days.
3. SBackup has pretty good scheduling. The frequency of full and incremental backups can be controlled. A purging schedule can also be set up, for example: keep all backups for the last week, keep one backup a month for the last year, keep one backup every 6 months for years before that.
4. SBackup's backups are software independent. This was a major problem I had with DAR, which I was using before SBackup: DAR archives couldn't be read without DAR. SBackup just uses tarred, gzipped files. So I have no worries about how I'm going to access the files in backup if SBackup is discontinued or unavailable in the future.
5. SBackup doesn't have encryption, but right now this is not crucially important to me.

In addition, SBackup really is very simple to configure, and it works silently behind the scenes.

Backup

I used to use Dar/KDar for backup purposes back when I was using SuSE 10.2. I've switched to Ubuntu, and it seems KDar is no longer packaged for Ubuntu. It got me thinking: what are the features that I want in a simple desktop backup application? Here are some in no particular order:

1. Network awareness. This is something I missed in Dar, which could only write to a directory on the system, which meant I had to ssh-mount a remote filesystem before I could back up to it.
2. Incremental and Full Backups.
3. A good scheduler. That is, it should be possible to specify the frequency and type of incremental and full backups, and a purge schedule for old backups.
4. Software independence. Dar used its own proprietary format, which forces me to use Dar to look at any of my backups. With KDar no longer available, it is quite painful to try to look at the contents of any of the older backup files. I have to get Dar to extract them somewhere, browse them and then delete them later. Something uses simple tar or tar.gz is much better; I can use Konqueror etc. to browse inside them directly.
   
5. Encryption is good if I'll be using NAS, otherwise it's not as important to me.

Maybe I'll add more requirements later.

Ubuntu 7.10, the T61 and External Monitors

I had a spot of bother trying to use an external monitor with Ubuntu 7.10 Gutsy Gibbon on a Lenovo T61. My T61 has an Nvidia Quadro 140M card and I'm using the proprietary (restricted) drivers.

I got a Lenovo Mini-dock and a Lenovo D221 monitor with my T61. When I connected everything up and put my T61 on the mini-dock and started it, everything appeared on the external monitor up to the Ubuntu splash screen with the progress bar. Right after that, the external monitor went blank and the T61's screen took over. (I think that happened when the X server was started, but not sure.) The same thing happened when I connected the external monitor to the T61 directly (not through the mini-dock).

To resolve this:

1. Connect the external monitor to the laptop directly
   
2. Open up a terminal, get root access using "su", and type "nvidia-settings &" at the prompt. This is a configuration program from the package "nvidia-glx-new" (I think it gets installed when you install the restricted nvidia drivers, but not sure).
   
3. Within nvidia-settings, select "X Server Display Information". It should show two monitors in a little box called "Layout". The external monitor may be disabled.
4. Click on the external monitor's icon, then click "Configure", then select "Separate X Screen".
5. Click on the laptop screen's icon (which is probably enabled), then click "Configure", then select "Disabled".
6. Note: This step will overwrite the X Confuration File (usually /etc/X11/xorg.conf). You may first want to backup that file to something like xorg.conf.bak.01. When you've backed it up, click "Save to X Configuration File".
   

When I restarted my X Server (or restarted the computer) after this, all output came out only on the external monitor, which is what I wanted.

However, this didn't solve the problem when I put the T61 on the mini-dock. I also had to connect the T61 and the external monitor to the mini-dock, and then repeat steps 2-6 with the T61 on the mini-dock.

Finally, when the T61 is not connected to the external monitor in any way, it should continue to work as usual. The above configurations don't affect this.

Caveats:

1. After doing this, there is an Nvidia splash screen every time the X Server is started up. This can be removed by editing /etc/X11/xorg.conf, but I don't detail that here.
2. After this reconfiguration, I began noticing that my GL Desktop window manager crashes very frequently. When that happens, I can resolve it by running System > Preferences > GL Desktop. But it is a bother.
   

Gnome Frustrations

The Gnome desktop environment, as packaged with Ubuntu 7.10 "Gutsy Gibbon", is a queer mix of liberating and frustrating. While it's got some great features and applets, and Compiz is pretty cool, it really falls flat on its face in some areas. While I understand that the Gnome people want to be minimalist, the extremes to which they go are counter-productive. Here are some of my gripes:

1. Their File Open dialogs don't have a place where you can type in a file location; you are forced to navigate to it using mouse clicks. This becomes really frustrating if you want to hide folders starting with a period ("."). I like to hide them because there are way too many and I access them only rarely. But when I do want to access them, Gnome makes it so difficult.
2. Having the option to see more information about what's going on during various operations can save a lot of frustration. I guess giving people access to information doesn't necessarily go against Gnome's philosophy; there could be an option to turn on extra information. One applet which frustrates me in this regard is the nm-applet which provides wireless access. The applet sometimes cannot connect to wireless networks, for example if I had to restart a wireless router. The problem is it keeps working away without allowing any kind of interaction. There is no option to cancel, no output indicating what it's doing; just the animation showing that it's working.
3. Gnome workspaces simply don't implement the best aspects of workspaces. The only thing you can do with Gnome workspaces is have different applications on different workspaces. What would be vastly more useful is to allow a different set of icons on each workspace. This is more important now that Gnome shows large thumbnail views of PDF files; there simply isn't enough space on a single workspace, and Gnome prevents users from effectively using the additional space that multiple workspaces provide. Allowing a different desktop background would nice too, but this is just eye candy.
4. Gnome has drawers, but these are too limited. You can't look at its contents and see what each element is. (The drawers just show identical icons for all PDF documents, for example.)
5. You can't select multiple applications on the taskbar (using Ctrl-click, for example) to close or minimize several windows at once! This is the worst regression I've seen. I once tried to open a large number of audio files with Audacity (thinking they would be queued in a playlist) and it opened up about 50 windows. I had to close them one by one.
   

So if you have a large number of documents that you want to organize on your desktop for quick access, there is no way to do it: you can't use workspaces because all workspaces have the same desktop icons, and you can't use drawers because you have no way to label a drawer or its contents.

And, this isn't Gnome's fault, but lack of good out-of-the-box hibernate negates all the benefits of having multiple desktops.