Add initial implementation

src/DearImGui/Plot.hs

@@ -1,2 +1,49 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+
 -- | DearImGui bindings for https://github.com/epezent/implot
 module DearImGui.Plot where
+
+import Control.Monad.IO.Class (MonadIO, liftIO)
+import Foreign
+import Foreign.C
+import qualified Language.C.Inline as C
+import qualified Language.C.Inline.Cpp as Cpp
+
+C.context (Cpp.cppCtx <> C.bsCtx)
+C.include "implot.h"
+Cpp.using "namespace ImPlot"
+
+newtype Context = Context (Ptr ())
+
+createContext :: MonadIO m => m Context
+createContext = liftIO do
+  Context <$> [C.exp| void* { CreateContext() } |]
+
+destroyContext :: MonadIO m => Context -> m ()
+destroyContext (Context contextPtr) = liftIO do
+  [C.exp| void { DestroyContext((ImPlotContext*)$(void* contextPtr)); } |]
+
+beginPlot :: MonadIO m => String -> m Bool
+beginPlot name = liftIO do
+  withCString name \namePtr ->
+    (0 /=) <$> [C.exp| bool { BeginPlot($(char* namePtr)) } |]
+
+endPlot :: MonadIO m => m ()
+endPlot = liftIO do
+  [C.exp| void { EndPlot(); } |]
+
+plotLine :: (MonadIO m) => String -> [Float] -> [Float] -> m ()
+plotLine desc xs ys = liftIO $ do
+  let size = fromIntegral $ length xs
+  withCString desc \descPtr -> do
+    withArray (map realToFrac xs) \xsPtr -> do
+      withArray (map realToFrac ys) \ysPtr -> do
+        [C.exp| void { PlotLine( $(char* descPtr), $(float *xsPtr), $(float *ysPtr), $(int size) ) } |]