Having gone through more than half of it already I’m rather surprised as to just how many different tools are available for solving concurrent problems and just how many are a instantly available to Java programmers. Unfortunately, and unsurprisingly, none of these tools in and of themselves are adequate enough for avoiding deadlocks and writing composable deadlock free code. My next step in the search for that silver bullet is to try writing something interesting in Clojure or Haskell using STM.

In this post I’ll document the steps I had to take to build DXX-Rebirth (a modernized Descent game engine) for Windows using MSYS and MinGW.

MinGW, MSYS

From  Pantokrator’s blog:

• install MinGW
  • choose a lowercase install path: c:\mingw
  • choose to download and install current version
  • enable g++ (for physfs)
• install MSYS
• install msysDTK

SDL and SDL_mixer

Also from  Pantokrator’s blog:

• download the SDL source
• in the MSYS shell, compile it with

./configure --prefix=/mingw && make && make install

• download the SDL_mixer source and in a MSYS shell, build it with the same command:

./configure --prefix=/mingw && make && make install

PhysicsFS

• Download the physfs 1.1.0 source.

• Compile with the same command again:

./configure --prefix=/mingw && make && make install

SCons and Python

From Globulation2 MinGW instructions:

• install Python 2.6
• install SCons
• add:

PATH=$PATH:/c/Python26:/c/Python26/Scripts

• to the end of /etc/profile in MSYS so that SCons can run from the MSYS shell.

Subversion

• install TortoiseSVN

DXX-Rebirth

• checkout DXX-Rebirth from https://dxx-rebirth.svn.sourceforge.net/svnroot/dxx-rebirth
• change the SConstruct script to call sdl-config as ‘sh sdl-config ‘:

...
Flags and stuff for all platforms...
env.ParseConfig('sh sdl-config --cflags')
env.ParseConfig('sh sdl-config --libs')
env.Append(CPPFLAGS = ['-Wall', '-funsigned-char'])
...

• finally, in the MSYS shell, built with:

scons sdlmixer=1

Final Remarks

I had trouble with the latest version of PhysicsFS (1.1.1) because it uses cmake. For some reason it failing to find some prerequisites in MSYS. I also had trouble with version 1.0.1 of PhysicsFS (this is the version the official d1x-rebirth_v0.55.1-win.zip is built with) because the built failed with the following error:

warning: cannot find entry symbol _DllMainCRTStartup@12; defaulting to 00401000
...
undefined reference to WinMain@16

If you notice any problems or mistakes in this post, please mention them in the comments.

What I liked

• importing images into the gallery using a separate and (seemingly) lower priority thread makes  the UI usable right from the start.
• it hasn’t crashed on me while importing 11,000+ pictures into the gallery
• cute, but useless timeline display application:
  
• Google provided an RPM repository which makes installing, upgrading and un-installing very easy for me

What I disliked

• simplified colour tuning controls. They might be OK for beginners, but they don’t appeal to someone like me who has used colour curves before.
  
• at first launch, Picasa started to import images from my whole home directory, which is huge and has tonnes of pictures. This only made me realize just how many images I have (mostly application icons and game project textures) that really don’t belong in a photo catalogue. I also couldn’t find a way to tell Picasa to stop and only look in certain directories.
• Picasa froze when I first tried the “tools > folder manager”. It worked on the second attempt, and I realized that this is the tool used to tell Picasa exactly what directories to include when searching for images.
• the “Tools > Experimental > show duplicate pictures” function was indeed experimental. It seemed to just give me a list of images without indicating what the duplicate pairs (or groups) were.
• the search results for the “show duplicate pictures” also showed a strange status bar at the top of the main window. I never figured out the meaning of the constantly changing seconds value or what GPixel was referring to.
  
• the “importing indicator”, although neat (it showed what picture was being imported in real time), was rather useless. Most importantly, it did not show the total progress percentage. When I tried to close it, it seemed to just re-appear in a different location along the side of the main Picasa window. Then it simply started sliding up and down without explanation.
• after a lot of clicking, I managed to loose the album list view in the left pane and had to re-start Picasa
• ugly dithered splash screen image – c’mon, we’re not in the 1990′s anymore!
• the scrollbar in the main view controls the view scroll speed, not the actual movement of the view – annoying and misleading. It didn’t let me get near the bottom right away, and I got dizzy every time I scrolled. However, I think the search result view actually changed the scroll bar function to the usual scroll bar for reasons beyond me. [Edit: after more use I realized that the way the scroll bar behaves in Picasa (combined with really smooth scrolling) helps with showing many photographs to other people looking at your screen. You can just drag the scrollbar just a bit to achieve a nice steady scroll speed and discuss the pictures instead of having to continually "pull" the images up or down with the mouse.]
• I somehow totally failed to find the familiar timeline/calendar view of my photos. Does Picasa really not have a way to organize photos in this manner?
  
• this is proprietary software from Google. I actually like a lot of stuff that comes from Google, but when it comes to software licensing, I don’t play favourites. I simply try to avoid non-Free Software as much as I can.

What I ignored

• uploading to and syncing with various web services
• ordering prints
• printing to a local/personal printer
• picture backup feature – rsync is fine for me
• passport photo function – This made me realize that I’m definitely not the intended audience of Picasa
• the ability to store video flies, which I consider to be outside of the scope of this program
• anything else I haven’t mentioned, obviously

Final thoughts

In conclusion, I’ve used my experience with Picasa to re-inforced my decision to stick with Digikam – a Free/OpenSource Software photo manager.

In Fedora 8, Jigdo was easy to install:
# yum install jigdo

From the jgdo manpage I discovered that the command line client version of jigdo is actually called “jigdo-lite”. Using this client turned out to be as easy as telling it which “.jigdo” file to use:

$ jigdo-lite http://www.muug.mb.ca/pub/fedora/linux/releases/9/Fedora/x86_64/jigdo/Fedora-9-x86_64-DVD.jigdo

Jigdo was nice enough to ask me to enter a path to previous installation media (presumably Fedora) to check for files which can be reused. To my amusement it turned out that the Fedora 7 x86_64 DVD contained no such files while the Fedora 8 x86_64 DVD contained 116 of the 2691 files required by the template.

Resuming jigdo was an interesting process. I canceled the first attempt with Ctrl-C. Then I simply re-ran the original jigdo command and it told me:

The temporary directory `Fedora-9-x86_64-DVD.iso.tmpdir' already exists. Its contents
ARE GOING TO BE DELETED (possibly after having been copied to the
image, if they are of interest for it). If you do not want this
to happen, press Ctrl-C now. Otherwise, press Return to proceed.

This puzzled me because it didn’t say what is the meaning of the files in the *.tmpdir directory. Without knowing that I shouldn’t be expected to assess the importance of the directory and make a decision about deleting it. My initial guess was that it contained everything that jigdo has downloaded in the previous session. I checked the “jigdo” and “jigdo-lite” mangpages but they did not mention resuming. Thankfully, the documentation on the website was more helpful. The Downloading Of The ISO section made it clear that I shouldn’t fear to loose Fedora-9-x86_64-DVD.iso.tmpdir after all. Apparently it simply stores files which have just been downloaded but haven’t been merged into the temporary image (which is called Fedora-9-x86_64-DVD.iso.tmp). I checked that currently Fedora-9-x86_64-DVD.iso.tmpdir is much smaller than Fedora-9-x86_64-DVD.iso.tmp so I feel confident in letting jigdo delete that dir:

$ ls -lah
total 3.9G
drwxrwxr-x  3 plouj plouj 4.0K 2008-05-14 15:48 .
drwxr-xr-x 25 plouj plouj 4.0K 2008-05-14 11:16 ..
-rw-rw-r--  1 plouj plouj 314K 2008-05-14 11:30 Fedora-9-x86_64-DVD.iso.list
-rw-rw-r--  1 plouj plouj 3.9G 2008-05-14 15:47 Fedora-9-x86_64-DVD.iso.tmp
drwxrwxr-x  4 plouj plouj 4.0K 2008-05-14 15:47 Fedora-9-x86_64-DVD.iso.tmpdir
-rw-rw-r--  1 plouj plouj 211K 2008-05-12 13:11 Fedora-9-x86_64-DVD.jigdo
-rw-rw-r--  1 plouj plouj  12M 2008-05-12 11:38 Fedora-9-x86_64-DVD.template
-rw-rw-r--  1 plouj plouj 3.0M 2008-05-14 11:30 jigdo-file-cache.db
$ du -sh Fedora-9-x86_64-DVD.iso.tmpdir
7.5M	Fedora-9-x86_64-DVD.iso.tmpdir

Find confirms the same:

$ find Fedora-9-x86_64-DVD.iso.tmpdir -type f
Fedora-9-x86_64-DVD.iso.tmpdir/gulus.usherbrooke.ca/pub/distro/fedora/linux/releases/9/Fedora/x86_64/os/Packages/lucene-contrib-2.3.0-1jpp.0.fc9.x86_64.rpm
Fedora-9-x86_64-DVD.iso.tmpdir/gulus.usherbrooke.ca/pub/distro/fedora/linux/releases/9/Fedora/x86_64/os/Packages/libpng-1.2.24-1.fc9.x86_64.rpm
Fedora-9-x86_64-DVD.iso.tmpdir/gulus.usherbrooke.ca/pub/distro/fedora/linux/releases/9/Fedora/x86_64/os/Packages/lftp-3.6.3-2.fc9.i386.rpm
Fedora-9-x86_64-DVD.iso.tmpdir/www.muug.mb.ca/pub/fedora/linux/releases/9/Fedora/x86_64/os/Packages/glibc-2.8-3.x86_64.rpm

After I pressed “Return”, jigdo happily resumed downloading my Fedora 9 DVD. Some time later, the download finished successfully and the resulting image passed the SHA1SUM check.

In addition to the resuming confusion I noticed a few other problems with Jigdo. Firstly, it just takes a long time to download and check all the files. It has been running for over 3 hours and at 500KB/s (the average speed I get from good servers) the whole DVD image (3970.8 MB) would have been downloaded by now. Secondly, the name is hard to spell correctly. I’ve gone from “Jingo” to “Jidgo” to “Figdo”.

To be fair, I have to admit that the coolness of what jigdo does in the background outweighs its shortcomings and I am happy with it in the end.