init

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