CHIP-8 is an old interpreted programming language, and I decided to create yet another interpreter for it, but in Haskell for fun !
I first learned about it on this French forum a while ago, there are a lot of C or C++ implementations online, and I thought it will be interesting to make it in Haskell instead.
The CHIP-8 wikipedia page has a lot of information about how to proceed.
I chose the SFML library (more precisely, its Haskell binding as it's a C++ library) because I have used it many times in the past.
Any other graphic library will fit, as only very basic features are needed, even ncurses would be suitable...
At the time I'm writing this, the latest SFML 2.x version is 2.6.2 and 3.0.0 came out recently, but the Haskell binding is quite late being 2.3 only.
Here's the SFML bindings download page and the SFML haskell binding page on Hackage.
Run (and build if not already) : cabal run Chip8
Run with arguments (and build if not already) : cabal run Chip8 -- path.ch8
Close the window either with the cross or by hitting Escape key.
The roms/ submodule contains an extensive collection of ROMs.
Its demos/ subdirectory contains basic programs, requiring little to no input, such as logos or a maze generator.
If you want more, CHIP-8 ROMs are very easy to find online.
Hackage's SFML has a build error, so I was forced to use its repository to make it build.
The submodule Haskell-SFML contains SFML source code, and Cabal can build it thanks to cabal.project which adds SFML directory to the Chip8 project.
Be warned, for now putting build-depends: SFML in your project's cabal file will cause a compilation error as it fetches Hackage.
Moreover, when building SFML, you'll see some warnings shown as errors, they look like this :
cbits/SFML/Graphics/Shader_helper.c:6:5: error:
warning: ‘sfShader_setVector2Parameter’ is deprecated [-Wdeprecated-declarations]
6 | sfShader_setVector2Parameter (shader, name, *vector);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
6 | sfShader_setVector2Parameter (shader, name, *vector);
| ^
In file included from cbits/SFML/Graphics/Shader_helper.c:1:0: error:
They are not errors, SFML successfully builds despite these scary-looking "error" messages, so do not worry.
The Haskell-SFML/demos subdirectory is contains some examples to show how to use the binding, but they don't build.
To fix the issue, go to the repository root directory and execute the [setup.sh] script, it will create a cabal.project config file to link the SFML directory to the demos.
Then, just do cabal build in the demos subdirectory and every demo will compile.
During the instructions implementation, I used various test ROMs from these two repositories :