BZFlag
Volume Number: 20 (2004)
Issue Number: 06
Column Tag: Programming
BZFlag
by Dave Mark
A SourceForge Open Source Project
Lots to talk about this month. There's a new version of Xcode up on the net, I got an excellent
new toy I'll touch on briefly, and for the main event, we're going to download and build an open
source Mac OS X program called BZFlag.
The Latest Version of Xcode
There's a new version of Xcode on the Apple Developer Connection web site. Definitely worth the
download. Make your way over to:
http://connect.apple.com
Login, then click on the Download Software link. Figure 1 shows the section of the page dedicated
to the new version of Xcode, version 1.2.
If you are working off of an unadulterated Panther install, chances are good that you won't have
an easy time using Safari to download the pieces that make up the new Xcode installer. Fortunately,
there's a nifty piece of freeware that will make your job much easier.
MisFox is from a German programmer named Alexander Clauss and allows you to edit all the file
mappings and protocol helpers used by Mac OS X. In our case, we want to set the FTP helper app to
whatever FTP client you happen to be dating at the moment. Here's the URL for MisFox:
http://www.claussnet.de/misfox/misfox.html
Figure 1. The Xcode
download listing in Safari.
When I wrote this, version 1.2.1 was the most recent release. Figure 2 shows the main MisFox
window. Note that there are 3 tabs to choose from: Default Applications, File Mappings, and Protocol
Helpers. I used the Default Applications tab to set my default FTP application to Interarchy.
Figure 2. The MisFox
Default Applications pane.
If you go back to Figure 1, you'll see a Download button to the right of the Xcode Tools 1.2 CD.
Once you use MisFox to set your default FTP client, Safari will hand the list of files behind that
Download button to your client for easy downloading.
Xcode 1.2 consists of 21 segments. Download them, and if they are not automatically reassembled,
just double-click on one of them. The disk image will be mounted and you can run the installer.
Obviously, make sure you backup your hard drive before you do the install, just in case something
goes horribly, horribly wrong.
When you first launch the new Xcode, you'll have a chance to go through the release notes to see
what's new with the new version. If you miss your chance, go to the Help menu and select Show
Release Notes. Lots of good info here. Still some issues to address, but lots of fixes, making this
release of Xcode more stable overall.
An Awesome New Keyboard
In the March 29th issue of TidBits, Adam Engst wrote a glowing review of the Tactile Pro keyboard
from Matias. Here's a picture of the keyboard:
http://halfkeyboard.com/tactilepro/
viewer/tp_mainpic.html
Here's Adam's eloquent review:
http://db.tidbits.com/getbits.acgi?tbart=07607
I live on my PowerBook. Have a 17" Apple Studio Display. But have never found a keyboard I was
really happy with. Until now. As you'll find when you read Adam's review, the designers made some
excellent decisions when it came to laying out the keyboard. But to me, the most important aspect of
this keyboard is its incredible responsiveness. The keys on my PowerBook keyboard are mushy. Perhaps
a better way of saying this is, I can't feel the micro-switches underneath the keys when I press
them. The keys on the Tactile Pro keyboard, however, clack when I press them, the reassuring clack
of a micro-switch being depressed. The throw of each key is deeper, meaning that I have to press
each key down further as I type. This might seem like a bad thing, but it is not. I can tell when
I've pressed a key and the Tactile Pro keyboard is much more forgiving that any other keyboard I've
tried. The result is much faster typing speeds with much higher accuracy.
If you've ever typed on the old Apple Extended Keyboard (think back to the days of the original
Macintosh II), you'll have a sense of the Tactile Pro. They used the same mechanical keyswitches,
and the result is brilliant. You can buy it online at http://tactilepro.com, $99.95.
Mac OS in an Open Source World
A long, long time ago, back before Cocoa and the second coming of Steven P. Jobs, the Mac was
pretty much an island. You were either a Mac person or you were not. When it came to Mac sample
code, there were some wonderful communities set up, but they were always either Apple-driven, or
catered for the most part to Mac people. If you found some cool Unix/X windows code, chances are
pretty good that any sample projects were set up for Windows or Unix-based environments, Mac folk
need not apply.
Now that Mac OS X has passed through the steep portion of its adoption curve, there is much more
of an acceptance of the Mac among the open source crowd. A perfect example of this can be seen at
the big dog of development web sites, http://sourceforge.net.
Now, you might think that your favorite web site has lots of sample code and a big community of
users, but no. This is big. SourceForge has more than 800,000 registered users (and that number does
not include the hundreds of thousands of developers who just like to poke around) and more than
80,000 hosted projects. Those are crazy huge numbers.
In the olden days, there might have been a few scattered Mac projects, but they would have been
few and far between. Navigate over to http://sourceforge.net and click on the software map button,
just below the banner ad towards the top of the window. Here's the URL that will get you there
directly:
https://sourceforge.net/softwaremap/
trove_list.php
This is a useful page if you are looking for a project and know the topic. But you can also
browse by other categories, including OS. Click on the Operating System link. Again, here's the
direct link:
https://sourceforge.net/
softwaremap/trove_list.php?form_cat=199
Figure 3 shows the OS categories, along with the number of projects in each category. More than
three thousand Mac OS projects. This is cool!
Figure 3. The list of
SourceForge projects, listed by OS.
If you click on Mac OS, and then on Mac OS X, you'll find 2,290 Mac OS X projects, 1,526 of which
are Cocoa projects. That is a pretty rich vein of interesting material to explore. And, who knows,
you might find a project that interests you so much that you'll dig in and get involved with the
development process. SourceForge (and Open Source, in general) is cool that way.
It is worth noting that there are many projects that support the Mac or will just plain run on
the Mac that are not necessarily in the MacOS category. For example, there are several thousand
Mac-savvy projects in the OS Independent and POSIX categories.
Read through the rest of this column, then start digging around, see what you can find.
Building BZFlag
Each month, SourceForge nominates a Project of the Month. This past April, the project of the
month was a cool tank-based shooter game named BZFlag. Here's a link to the SourceForge BZFlag page:
https://sourceforge.net/potm/potm-2004-04.php
Cool! Pictures of Tim Riker, David Trowbridge, and Sean Morrison, BZFlag's key developers. The
page contains a lot of interesting info, including an interview with the principals. This is pretty
typical of a "potm" (project of the month) page. The potm URLs are well constructed, so you replace
the 2004-04 with a 2004-03 to get to the March project of the month:
https://sourceforge.net/potm/potm-2004-03.php
The potm page is more of a marketing page. On it, you'll find a link to the SourceForge BZFlag
Project page:
https://sourceforge.net/projects/bzflag
This is the actual SourceForge home for BZFlag, where you'll go to download the various
sources and binaries for the different platforms BZFlag supports. These pages are very well
organized. Figure 4 shows the listing of recent BZFlag file releases. The link at the bottom of the
figure takes you to a page with a much more exhaustive listing.
Figure 4. The list of
recent BZFlag file releases on the project page.
If all we were interested in was the app itself, we could download the binary for our platform.
Now BZFlag is a lot of fun to play, but there's something gratifying about successfully building an
app on your own machine, especially an app as complex as this one.
Click on the bzflag source link towards the bottom of the list. Be sure to click on the one with
the most recent date. As you can see, I'll be working with the one labeled April 25, 2004.
This link will take you to a page listing various source releases, including the one you
selected. Source code is archived in a number of different ways, depending on the OS. In general,
you do not want to download a .zip file. This will likely be a build intended for a Windows machine.
The permissions will not be setup for Mac OS X, and there will also likely be carriage return/line
feed confusion as well. For Mac OS X, look for a tar.bz2 or a tar.gz archive.
Click on the link labeled:
bzflag-1.10.5.20040426.tar.bz2
This will take you to a download page. Select your nearest location and click the link to start
the download. StuffIt Expander will expand the archive just fine.
In the Finder, open the newly expanded directory. In my case, it was called
bzflag-1.10.5.20040426. Now open the subdirectory src/platform/MacOSX. As the name implies, these
are the build files for Mac OS X.
When the Xcode project window appears, click on the targets popup menu (it's in the upper-left
corner) and select BZFlag (Figure 5).
Figure 5. The BZFlag
targets popup from the BZFlag project window.
Now select Build and Run from the Build menu. This is gonna take a while, so this might be a good
time to alphabetize those Zamfir pan flute CDs you've been collecting.
When you start the build, if nothing appears to be happening, it may be that you have the split
closed in your build window. If your build window is not divided into two distinct panes, click on
the dot on the bottom edge of the window and drag it up, towards the middle of the window (Figure
6). The build is driven by a set of Makefiles (Unix build scripts) and the script steps are shown in
the bottom pane, while Xcode's compile messages will be shown in the top pane.
Figure 6. Be sure you
split your build window by dragging the dot from the bottom of the window towards the middle.
If you get an error message during the build process, try changing the target to BZAdmin, doing a
Build of that target, then selecting BZFlag as a target and doing a Build and Run again. Worst case,
do a Build of the Everything target, then select BZFlag and do a Run. You need to run the BZFlag
target to run the game.
Have fun playing BZFlag. It will take over the entire screen and put up a simple menu. Navigate
the menu with the arrow keys and the return key. Escape takes you back up a level. Your choices are
Join Game, Options, Help, and Quit. Review the help and options if you like, then select Join Game.
This will take you to a new menu screen. Select Find Server, scroll through the list of servers to
find a game you like, select the game, then select Connect.
That's it. You're in the game. And there is always a game going. It is amazing how big this game
has gotten. When you are done playing, hit escape, then arrow down to Quit.
Doing a Unix Build
Not every Mac OS X project will ship with an Xcode project. That's OK, though. As long as the
developers included the appropriate make files, we can use those to do our build. So if you had some
trouble with your Xcode build or if you just want to give the Unix build process a try, here's the
process.
Use the cd command to navigate into the top level of the BZFlag folder you downloaded. For
example, I unstuffed my archive onto my desktop. From my home directory, I did:
cd Desktop
and then I did:
cd bzflag-1.10.5.20040426
I then did:
./autogen.sh
The leading "./" tells the Unix shell to execute the shell script contained in the file
autogen.sh found in the current directory, that is, in the directory bzflag-1.10.5.20040426.
The script hangs a bit, then spits out this message:
BZFlag sources are now prepared. To build here, run:
./configure
make
And that's exactly what you want to do next. First, type:
./configure
This will create a bunch of Makefiles and do a few other things. When it is done, type this
command:
make
Got a dual processor G5? If so, do a:
make -j2
This tells make to split the task into two concurrent jobs. Gets the job done in half the time!
This will take a while. You'll be compiling a fairly large batch of code, so sit back and dream
about Gilligan's Island. Who would you be? Hmmm...
By the way, in case you were wondering, gcc is the C compiler, and g++ is the GNU C++ compiler.
The build should take about 10 minutes (obviously, depends on your processor). To run the binary,
be sure you are still in that top directory and type the command:
src/bzflag/bzflag
If you get an error message, do an ls and verify that there is a directory named src in the
current directory. If not, you may have changed directories
Till Next Month...
Hopefully, between the Xcode method and the Terminal method, you've gotten BZFlag to run. Here
are a couple of BZFlag related sites that can help you with your gameplay:
http://www.dervishdukot.org/home/bzflag/bzflag.html
http://bzflag.org/wiki
Also, if you are IRC-savvy, you can make your way over to #bzflag on irc.freenode.net with any
questions or comments.
Your homework assignment is to search through some of the other Open Source projects on
SourceForge.net listed in the Mac OS X area, find one you like, and get it to build.
A huge shout out to Sean "brlcad" Morrison for his most excellent help in getting BZFlag to
build.
Oh, and be sure to head over to http://www.spiderworks.com and sign up for the email list. See
you next month...
Dave Mark is a long-time Mac developer and author and has written a number
of books on Macintosh development. Dave has been writing for MacTech since its birth! Be sure to
check out Dave's latest and greatest at http://www.spiderworks.com.
