Sadly the game crashes upon opening so I wasn't able to try it out (Windows Server 2008 R2 SP1). No error message, just a generic windows crash. Was really looking forward to this one, because I loved the title ^_^

I can't figure out how to compile this on my 32-bit ubuntu 10.10 box. I can see that I have to install libsfml-dev but I seem to be missing something else.

If you have sfml development files the following command should compile it for you :
g++ mainloop.cpp mob.cpp turret.cpp -lsfml-system -lsfml-window -lsfml-graphics -lsfml-audio -o OMFGAliens

Then run ./OMFGAliens to try the game

Let me know if this doesn't work, and what error you got.

I was stupidly waiting for the start screen to clear out, pressing any key I could think of. Until I found out that I had to hit "escape". You should add this to the readme.

It was fun, although I suck as this game. The towers felt to have some kind of annoying range: sometimes they could hit an alien, but they couldn't hit an alien that was seemingly in the same range.

Their range is a 50 pixel (5 square) circle, calculated using good old Pythagoras' theorem.

The reason it looks like turrets sometimes have trouble hitting an alien is due to the ract that they have a lock-on time, and they randomly try to target a new enemy each frame if their current target is out of range or dead.
So while an enemy is perfectly in range, there's a time for them to find the target (1 in however many living enemies there are chance per frame), so if there are 10 living aliens and only one in range, it will take an average of 10 frames (or half a second at the enforced 20fps) to target. Then, there are another 15 frames of warm-up (3/4 of a second) before firing starts.

All in all, this means that there's a good second of lag between an enemy coming in range and the turret beginning to engage. If the enemy exits and reenters that range, the warm-up resets, and there's also the chance that he gets replaced by another target.

I realise now that targeting and warmup should have been made visible (dim red "laser pointer" from turret to target and some sort of charge up effect), the only pre-shot effect I have is the turret flashing magenta the frame before shooting (note that if the enemy gets out of range on the frame he would have been shot, then the magenta flash happens, but the turret doean't fire, I think this glitch is rare enough not be noticable.)

Not bad idea, but after several attempts I feel like it's not much I can do due to the total randomness... I couldn't understand why turrets sometimes shoot, sometimes don't, sometimes disappear (did I get it right? do they really disappear after some time?)

They disappear when their 100 ammo runs out. You have a quick visualation of remaining ammo as grey bars above each turret.

It's too buggy for me to have fun. About 80% of the time I click to place a turret, the cost is subtracted but no turret is added!

Good audio though, and I like the movement of the "aliens." :)

Surprising complex emergent strategy (balancing money-earning turrets in the middle with safety turrets near the edges). Soundscape was great, and the retro graphics served their purpose well. Great original concept.

Unfortunately, there was a bit too much luck involved, and the depth of the strategy broke down pretty quickly as you played. Considering the time you have to tune and balance in this competition, though, not bad.

I'd definitely like to see this idea expanded on a bit, and designed/balanced some more. Nice work!