From 23498c064aa6a7e0c58a7d80581a7514aa4c0a37 Mon Sep 17 00:00:00 2001
From: mtgmonkey <mtgmonkey@nixos>
Date: Wed, 26 Nov 2025 01:34:43 +0100
Subject: [PATCH] init

---
 flake.lock  | 26 ++++++++++++++++++
 flake.nix   | 21 +++++++++++++++
 package.nix | 43 ++++++++++++++++++++++++++++++
 src/Main.hs | 77 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 167 insertions(+)
 create mode 100644 flake.lock
 create mode 100644 flake.nix
 create mode 100644 package.nix
 create mode 100644 src/Main.hs

diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..5c6f215
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,26 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1763966396,
+        "narHash": "sha256-6eeL1YPcY1MV3DDStIDIdy/zZCDKgHdkCmsrLJFiZf0=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "5ae3b07d8d6527c42f17c876e404993199144b6a",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "ref": "nixos-unstable",
+        "type": "indirect"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..79e4a63
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,21 @@
+{
+  inputs = {
+    nixpkgs.url = "nixpkgs/nixos-unstable";
+  };
+  outputs = {nixpkgs, ...}: let
+    system = "x86_64-linux";
+    pkgs = nixpkgs.legacyPackages.${system};
+  in {
+    packages.${system} = {
+      default = pkgs.callPackage ./package.nix {};
+    };
+    devShells.${system} = {
+      default = pkgs.mkShell {
+        nativeBuildInputs = [
+        ];
+        shellHook = ''
+        '';
+      };
+    };
+  };
+}
diff --git a/package.nix b/package.nix
new file mode 100644
index 0000000..ff17a7a
--- /dev/null
+++ b/package.nix
@@ -0,0 +1,43 @@
+{
+  haskellPackages,
+  lib,
+  stdenv,
+  pkgs,
+  ...
+}: let
+  ghcExeOptions = "-Wall -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints -threaded -rtsopts -with-rtsopts=-N";
+  ghcPackages = p: [
+    p.OpenGL
+    p.GLFW-b
+  ];
+in
+  stdenv.mkDerivation {
+    pname = "haskengl";
+    version = "0.1.0";
+    src = ./src;
+    nativeBuildInputs = [
+      (haskellPackages.ghcWithPackages ghcPackages)
+      pkgs.libGL
+      pkgs.libGLU
+    ];
+    buildInputs = [
+      pkgs.libGL
+      pkgs.libGLU
+    ];
+    configurePhase = ''
+    '';
+    buildPhase = ''
+      ghc ${ghcExeOptions} ./Main.hs -o ./Main
+    '';
+    installPhase = ''
+      mkdir -p $out/bin
+      cp ./Main $out/bin/haskengl
+    '';
+
+    meta = {
+      homepage = "https://mtgmonkey.net";
+      license = lib.licenses.wtfpl;
+      mainProgram = "haskengl";
+      platforms = ["x86_64-linux"];
+    };
+  }
diff --git a/src/Main.hs b/src/Main.hs
new file mode 100644
index 0000000..14e2c76
--- /dev/null
+++ b/src/Main.hs
@@ -0,0 +1,77 @@
+module Main (main) where
+
+-- IMPORTS --
+
+import Graphics.Rendering.OpenGL as GL
+import Graphics.UI.GLFW as GLFW
+import Control.Monad (forever)
+import System.Exit (exitSuccess)
+
+-- MAIN --
+
+main :: IO ()
+main = do
+  putStrLn "haskengl 2025 Andromeda; WTFPL"
+  window <- openWindow "window :)"
+  onPaint window
+  closeWindow window
+  return ()
+
+-- EVENTS --
+
+keyPressed :: GLFW.KeyCallback
+keyPressed window GLFW.Key'Escape _ GLFW.KeyState'Pressed _ = shutdownWindow window
+keyPressed _ _ _ _ _ = return ()
+
+-- PAINT --
+
+onPaint :: GLFW.Window -> IO ()
+onPaint window =
+  do
+    GL.clearColor $= Color4 1 0 1 1
+    GL.clear [ColorBuffer]
+    GLFW.swapBuffers window
+    forever $ do
+      GLFW.pollEvents
+      onPaint window
+
+-- WINDOW --
+
+openWindow :: String -> IO GLFW.Window
+openWindow
+  title
+  = do
+    GLFW.init
+    GLFW.defaultWindowHints
+    GLFW.windowHint (GLFW.WindowHint'ContextVersionMajor 4)
+    GLFW.windowHint (GLFW.WindowHint'ContextVersionMinor 5)
+    GLFW.windowHint (GLFW.WindowHint'OpenGLProfile GLFW.OpenGLProfile'Core)
+    monitor <- GLFW.getPrimaryMonitor
+    Just window <- GLFW.createWindow 256 256 title monitor Nothing -- get an error n ur cooked. TODO graceful failure here
+    GLFW.makeContextCurrent (Just window)
+    GLFW.maximizeWindow window
+    GLFW.setWindowCloseCallback window (Just shutdownWindow)
+    GLFW.setWindowSizeCallback window (Just resizeWindow)
+    GLFW.setKeyCallback window (Just keyPressed)
+    return window
+
+shutdownWindow :: GLFW.WindowCloseCallback
+shutdownWindow window =
+  do
+    closeWindow window
+    _ <- exitSuccess
+    return ()
+
+resizeWindow :: GLFW.WindowSizeCallback
+resizeWindow _ w h =
+  do
+    GL.viewport $= (GL.Position 0 0, GL.Size (fromIntegral w) (fromIntegral h))
+    GL.matrixMode $= GL.Projection
+    GL.loadIdentity
+    GL.ortho2D 0 (realToFrac w) (realToFrac h) 0
+
+closeWindow :: GLFW.Window -> IO ()
+closeWindow window =
+  do
+    GLFW.destroyWindow window
+    GLFW.terminate