Building a Haskell game

Sometimes building a package with dependencies on OpenGL can be a little confusing for people new to Haskell. I will use a simple game on Hackage as an exercise for demonstrating how you might do this on Ubuntu. Note: this was written before Stack was a thing.

This is as much about demonstrating how to show your process as it is about how to install a game.

So our objective is to build and run a game named Shu-thing on Hackage.

First, I used cabal unpack to download the game’s sources. Then I changed into the project directory and created my Cabal sandbox. To see more about how to use sandboxes, see my HowIStart tutorial.

Then, with the sandbox ready to go I started to install the dependencies for the project.

But it failed, something about needing a C library. My next step was to Google search “Missing C Library: GL” so I could find the resolution.

I chose the first link because it mentioned Gloss, which I know to be a Haskell library and thus likely relevant to my problem than a generic OpenGL issue. Realistically, any language would need to install the same OpenGL dependencies, but starting with the most specific questions/answers first is usually best.

There I saw instructions to install the appropriate GLUT dependencies for Debian/Ubuntu-alike distributions. I was using Ubuntu, so this suited me fine. This also matched what I knew about Shu-thing because its only dependency other than base was in fact GLUT.

This is me firing off those instructions.

Then I re-ran the dependencies install with cabal install --only-dependencies because that was the last thing to fail, and it succeeded. Next step was to build the executable for Shu-thing itself with cabal build. This also succeeded and reached the linking stage, which also didn’t fail.

Then I checked the game out which had a nifty wireframe aesthetic :)

The point here is that I didn’t know how to build this game or get it working 15 minutes before I started on this blog post and it wouldn’t have done as much good to just dump a listing of instructions. Rather, it was more important “show my work”, even if that entailed just googling for what dependencies I needed.

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