Time for my new game, White Butterfly! It's a shoot-em-up with three stages, five fighters and hours of agonising fun.

Makes extensive use of Allegro's 8-bit transparency and palette shifting. It also has code-generated music, some of it a bit random. Supports joystick control.

Depot page.

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Also, there are some videos by ortoslon (who is insanely good at it) here.

Windows only for now, but source is available (under the GPL) and it should compile for Mac and Linux.

Have fun! And let me know what you think.

What's this for, as in, which directory does it need to write to that is write-protected? Or rather, why not save to c:\users\public or c:\users\current_user?

If that's for the installer, why doesn't it let you choose where to install the game to (and therefore, where save files will go)?

It looks pretty good from the screenshots.

The default is to write configuration details to the directory where all the game files are. When I released Garden of Coloured Lights I got some feedback that Mac OS X and possibly also Windows Vista might be set up with the application directory write-protected, and Thomas Harte contributed some code to detect the appropriate directory to write to instead. I don't really understand how it works, sorry (never used Vista or OSX).

There isn't an installer, because I don't know how to make one. It's just a zip of the files.

It crashed in linux during the initial loading screen. Here is a useless stack trace.

Program received signal SIGABRT, Aborted.
[Switching to Thread 0xb7b6a6b0 (LWP 21339)]
0xb7f66410 in __kernel_vsyscall ()
(gdb) bt
#0  0xb7f66410 in __kernel_vsyscall ()
#1  0xb7bc7085 in raise () from /lib/tls/i686/cmov/libc.so.6
#2  0xb7bc8a01 in abort () from /lib/tls/i686/cmov/libc.so.6
#3  0xb7bffb7c in ?? () from /lib/tls/i686/cmov/libc.so.6
#4  0xb7c07a85 in ?? () from /lib/tls/i686/cmov/libc.so.6
#5  0xb7c0b4f0 in free () from /lib/tls/i686/cmov/libc.so.6
#6  0xb7e5f3da in _al_free () from /usr/lib/liballeg.so.4.2
#7  0x00000000 in ?? ()

Okay, thanks for letting me know. I'll check it out tomorrow.

That's actually my preference, so good deal.

I tried the game in wine and it ran fine.

The game looks nice and I like the weapons. I have some of the same gripes that I had with Garden of Colored Lights.
1. one shot to be killed is annoying when the screen is littered with bullets. this just seems like an artificial difficulty
2. I confused the bullets with the background, but much less than in Garden of colored lights

but overall its still quite nice. good work!

It's a really cool game. It has some interesting weapons, too (like the homing weapon of the hand of xom, like worth checking the code to see how you did it). I've just got a hiscore of 3360 on normal and barely reached Level 3 (that's a lot bullet-dodging against Level 2 Boss). I muted the music though, but everything else is quite nice.

I guess this is the usual on this kind of games.

Great game! I really like all your games aesthetic approach.
I am curious about how did you write this particular effect (I mean the trajectory of the bullets) did you use bezier curves perhaps?
http://www.allegro.cc/files/attachment/597747
I have been thinking in implement the same effect for some time.

Saw the video, pretty awesome. I am not into shmups a lot, but it looks just like what you would expect: bullets everywhere. Looks like you are using the american system (where a bullet anywhere kills you) instead of the japanese one (where the bullet must hit the cockpit). Maybe adding a shield or some power that lessens the amount of bullets?

Looks pretty awesome - no idea how you get the cool graphic fx
Anyway, good job

I played it, nice GFX, I like the retro looking and the laser ala Albator :-)

Actually the only part of the player ship that's vulnerable is the small white area in the centre, the part that's the same shape for all of them.

I considered giving some of the fighters defensive weapons capable of blocking bullets, but decided that would be too hard to balance.

No bezier curves. The seeker missiles work on the same principle as the worm weapons in Overgod and the charge seekers in Excellent Bifurcation.

Basically, each is a bullet object with an x/y position, x/y speeds and an angle. Each tick the bullet:
a) turns towards its target by a certain amount
b) accelerates a certain amount in <angle> direction
c) has its speed on each axis reduced by 5% or so.

This results in the curving motion.

The trails are just a series of lines between the bullet and its previous position, then from there to the next position, etc.

In WB the trails are bit more complex because instead of lines there are a series of transparent 8-bit RLE sprites drawn with do_line, but the principle is the same.

I've just finished it on normal with a hiscore of only about 8300. It gets frustrating at times but still you can't stop playing it. I don't think I'll be trying any other difficult level though, since normal was already too difficult for me.

I don't really get the weapon levels. Stage 3 was just as difficult for me with level 4 weapons as it was the first time I reached it with level 0 weapons.

Nice graphics, and good sounds, along with a nice assortment of ships and effects. I've only made it to the second stage on normal difficulty, and that's pretty difficult to get to anyway. Perhaps a slight increase in the scoring awards might be nice.

The anemone ship with the melee weapons is too difficult to play with effectively, and the hand of Xom is really effective until you reach the 3rd area in stage 1 where the enemies movements start to be erratic.

The game says the hand of Xom ship has a closed hand and an open hand weapon, but I can't see any difference between the two. Pressing fire 2 or fire 3 just charges the thing at it's last position, but is it actually doing anything other than making noise and looking pretty? It's also not clear how to level up the 3rd weapon for the hand of Xom.

In stage 1 between the 2nd and 3rd boss, the large amount of bubbling background stuff makes it difficult to see the projectiles.

The spinneret's orb beams shorten when you move up the screen, and lengthen when you move down the screen. It makes more sense to me that they should have a variable length that is irrespective of the ship's vertical movement.

The hand of xom is my favorite ship, so here's what I've figured out (the actual author description might be different). If you get close to an enemy so that it's within the circle, then the hand will home in to the enemy and may actually automatically destroy it; that counts for leveling up the second weapon. If, after the hand has home into a target, you press Fire 2 or 3, the hand will "open" and remain in that place. If you destroy enemies with the "open hand", that counts for leveling up the third weapon.

The hand of xom makes beating all bosses a piece of cake, except for that small boss at the end of Stage 2.

Very fun game.
Also, very hard.

I suspect that if I had a gamepad or the game supported using the mouse in some clever way it would be a bit easier. (especially with how the keyboard just loves to ignore the wrong keys when you are pressing what it decided to be too many :S)

Anyway, not that I'm very good (Highscore 11395 on normal, only got to stage 2), but one very important tip is to stress the offensive - destroying enemy ships before they get to shoot helps immensely.

Here is a patch for Linux. prepare_circles() is buggy on other platforms too. I added a CMake file for my own testing, which you can keep or not.

It's really addictive, and really hard! I still can't pass the first level.. -__-
The graphics are well made. Maybe it's because I never played shoot 'em up games before, but most of the time, I got lost among the particles! And I even thought some of them can be picked up -___- I wish I can make something like this in the future, because I'm still stuck on my Space Invaders clone xD

Second that.