First!



Space Pants Games - that's me, Julian / LongAnimals, and Ben / Asute deciding to make some games for the Sega Megadrive / Genesis.

Why?

Pretty much for fun. I wanted to get low and dirty after using Unity for so long. I made Genesis games in the 90s, and it's one of my favourite consoles to write games on. I wondered how much easier it would be to make games these days compared with using the tools available in 1994! More on that later, but here's a taster: it's MUCH easier now.

I started playing with the Genesis in early December 2020, taking some time away after a major release for the Day Job.

I found SDGK by Steph, and had a play with it. It really is some great work, a full C engine for Megadrive. Whenever I'm asked what game to make by people learning to code for the first time, I start with Pong, and work up to other old games, including Asteroids. So I put my money where my mouth was and made a little Asteroids game in C, in SGDK.

Something  like this: C Asteroids Demo




It went smoothly. C started coming back to me, as did memories of the Genesis hardware. 

But something was wrong. I felt dirty using someone else's system, and even dirtier using C. C compilers have come on a lot, I'm sure, but performance used to be terrible last time I looked at C on a Megadrive. We heard that people used C for these games in the 90s, and you could usually tell because they'd slow down a lot!

So no, this wasn't what I wanted to do. 

I started looking round for 68k assemblers. I use Windows, and there didn't seem to be many options, and I downloaded and set up Easy68k, copied some stub code from the internet, and started from scratch.

Now at this point I also needed tools. SGDK has lots of lovely resource management and converters, but I don't have any of that. I also wanted to use this opportunity to learn more about the editor side of Unity, and decided to use that to make my entire toolset.

So, over the next few days I hacked together a few demos, building up the tools for converting PNGs to Genesis tilesets, sprites, and palettes.

I started with Asteroids again, then Boulderdash for the tile scrolling, and Scramble for sprite spawning.




Asteroids Video  

Boulderdash Video  

Scramble Video

This was it. I was enjoying myself! My 68000 code was still very rusty, but it was coming back to me, and I found myself typing code without thinking. 

Next time.. moving on to something more substantial..




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