Create README.md
Create README.md

# bitquest

This is a tiny application that displays a [fancy picture](bitquest.png) on a real IBM PC XT with a CGA display. 

At least, it's supposed to. It works in [DOSBox][dbox] as well as [PCjs][pcjs]. As I'm lacking an IBM PC XT, I can't try it out on real hardware. I think it'll work, but it might as well set your machine alight. 

[dbox]: http://www.dosbox.com/
[pcjs]: http://www.pcjs.org/devices/pc/machine/5160/cga/256kb/demo/

## I really want to run this!

### DOSBox

Run `dosbox bitquest.com`, run `bundle exec rake`, or do whatever you usually do when you want to run a .COM file from a stranger on the internet. Go ahead, I won't judge you.

### PCjs

Download [floppy.img](floppy.img), then hit [this](http://www.pcjs.org/devices/pc/machine/5160/cga/256kb/demo/) page on pcjs.org that offers a virtual IBM PC with the right hardware. Wait for the prompt, then mount the image using the controls on the bottom left of the emulated screen. 

Run the application by entering "bitquest" on the prompt. (I'd be surprised if you didn't know that, though.)

## Customization

This project uses Rake. To build it, install nasm, then fetch all Ruby dependencies:

    bundle install

Finally, run:

    bundle exec rake

This converts all PNG images to a file format compatible with the 04h video mode (4-bit CGA), builds the .COM executable with nasm, then runs DOSBox. If you don't want to run DOSBox, run `bundle exec rake build` instead.

There's nothing special about the PNG file, so if you want to, you can make your very own picture. The only constraints are a resolution of 320x200 and the four-color palette (see bitquest.png).

## Credits

* [Bitcoon](http://bitcoongames.com/): Being a raccoon, and also [inspiring me to do this](http://www.furaffinity.net/view/16194622/)

## Useful references

* [TECH Help!](http://webpages.charter.net/danrollins/techhelp/0066.HTM): An old online version of an even older reference for 80x86 systems.
meowy/bitquest