F# and OpenTK together This sample is adopted from the C# example in http://www.opentk.com/doc/chapter/0

gistfile1.txt

// Released to the public domain. Use, modify and relicense at will.
//#r "OpenTK.dll"

open System
open System.Drawing
open System.Collections.Generic

open OpenTK
open OpenTK.Graphics
open OpenTK.Graphics.OpenGL
open OpenTK.Input

type g() as this =
    inherit GameWindow(800, 600, GraphicsMode.Default, "http://www.opentk.com/doc/chapter/0")
    
    do this.Resize.Add(fun e -> GL.Viewport(0, 0, this.Width, this.Height))

    do this.Load.Add(fun e -> this.VSync <- VSyncMode.On)

    do this.UpdateFrame.Add(fun e -> if this.Keyboard.[Key.Escape] then this.Exit())

    do this.RenderFrame.Add(this._RenderFrameEvent)

    member this._RenderFrameEvent e =
        GL.Clear(ClearBufferMask.ColorBufferBit ||| ClearBufferMask.DepthBufferBit)

        GL.MatrixMode(MatrixMode.Projection)
        GL.LoadIdentity()
        GL.Ortho(-1.0, 1.0, -1.0, 1.0, 0.0, 4.0)

        GL.Begin(PrimitiveType.Triangles)

        GL.Color3(Color.MidnightBlue);
        GL.Vertex2(-1.0f, 1.0f);
        GL.Color3(Color.SpringGreen);
        GL.Vertex2(0.0f, -1.0f);
        GL.Color3(Color.Ivory);
        GL.Vertex2(1.0f, 1.0f);
 
        GL.End();

        this.SwapBuffers()
        
/// <summary>
/// The main entry point for the application.
/// </summary>
let game = new g()
do game.Run(60.0)