ZGBJAM

Summer has become that time of the year when I stop everything I am working on and focus on ZGB for a few weeks. The bitbitjam wasn't finally hold this past year and we were missing a bit of retro-action so I talked with sergeeo (who takes care of the Familiar Game Jam) about holding a 48h mini-jam specifically for the Game Boy and using only the ZGB engine. The jam was online but a small group of people gathered together on my current company Genera Games.

As usual to avoid people bringing their creations before the start of the jam we picked a theme: bouncing. The jam was celebrated during the weekend of July 27th-29th 2018. You can still access the jam website and play all the 8 entries:

Upwell by Tatos A Downwell demake wannabe that even caught the attention of Ojiro Fumoto

Boun-Ma-Ze by Deebrol Bouncing is the only thing you can do to avoid being killed by enemies in a maze

Axebound by MaikelOrtega An unfished prototype of a warrior throwing bounding axes to cephalopods. There is a color version available too, and it has bg music!

Dungeon Ball by sergeeo A platform game where you have to guide your bouncing ball to the end of the level avoiding spikes. The music is great!

Deck Bouncer by Fronze Guide the ball to the end of the level changing its direction with the proper card

Shield Bouncer by me! You need to guide a bouncing ball with your shield to the end of the level. After this 2 years this is the first Game Boy game I had worked on alone

Basket Case Boy by David Erosa You have to place the proper platform to make the ball enter the basket

Buggy Troll Minigolf by Daniel Márquez A minigolf with an amazing power bar

All the games are playable on emulators and also on real hardware (a couple of them can be playable directly on your browser too). If you want to take a look at how the jam was taking place take a look at this link on twitter

This jam was the first time where I was able to see people using ZGB in person for the first time and thanks to that I fixed a few things that were causing a lot of issues:

• ZGB installation process has become way simpler that it was. Instead of a lot of links to download the files I had prepared a package that contains everything and from now on you just need that package and set the ZGB_PATH
• Backslashes on ZGB_PATH were causing a lot of headaches since msys requires slashes on paths. This has also been automatized
• Fixed file header dependencies. A lot of bugs were caused when changing a header file (exporting sprites or bitmaps for example) but not recompiling the sources using it. This is now integrated in the makefile. Build times are a bit longer now but you no longer need to rebuild the whole project all the time
• The number of steps required to add a new sprite have been reduced a lot:
  - By using C X-macros (thanks Carlos for your great post!) now all sprite and map info is declared on ZGBMain.h
  - Headers for sprites and states are no longer needed (you can still declare them if you want)
• Fixed Game Boy Color sprites palettes isue

The tutorials have also been updated with all these changes

Sadly there are some other stuff I can't do much about. The Game Boy is an 8-bit machine with lots of limitations and this is the first thing to consider when developing for it. It doesn't have float points so fixed point 8:8 is your only choice here, understanding how it works and using the fixed type declared in GBDK is the way to go. Because the theme of the jam was bouncing using fixed was almost mandatory.

Will there be a ZGBJAM 2? If people are interested on it, of course. We also hope this new year 2019 that there will be a new edition of the bitbitjam, we were really missing it last year!