#region --- License ---
/* This source file is released under the MIT license. See License.txt for more information.
 * Coded by Erik Ylvisaker and Stefanos Apostolopoulos.
 */
#endregion

#region --- Using directives ---

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;

using OpenTK.OpenGL;
//using Enums = OpenTK.OpenGL.GL.Enums;
using OpenTK.Platform;
using System.Threading;

#endregion

namespace Examples.WinForms
{
    public partial class W02_Immediate_Mode_Cube : Form, IExample
    {
        static float angle = 0.0f;

        #region --- Constructor ---

        public W02_Immediate_Mode_Cube()
        {
            InitializeComponent();
        }

        #endregion

        #region OnLoad

        protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);

            glControl.KeyDown += new KeyEventHandler(glControl_KeyDown);
            //glControl.Resize += new EventHandler(glControl_Resize);
            glControl.Paint += new PaintEventHandler(glControl_Paint);

            Text =
                GL.GetString(GL.Enums.StringName.VENDOR) + " " +
                GL.GetString(GL.Enums.StringName.RENDERER) + " " +
                GL.GetString(GL.Enums.StringName.VERSION);

            GL.ClearColor(Color.MidnightBlue);
            GL.Enable(GL.Enums.EnableCap.DEPTH_TEST);

            Application.Idle += Application_Idle;

            //glControl_Resize(glControl, EventArgs.Empty);
        }

        #endregion

        #region OnClosing

        protected override void OnClosing(CancelEventArgs e)
        {
            Application.Idle -= Application_Idle;

            base.OnClosing(e);
        }

        #endregion

        #region Application_Idle event

        void Application_Idle(object sender, EventArgs e)
        {
            while (glControl.IsIdle)
            {
                Render();
            }
        }

        #endregion

        #region private void Render()

        private void Render()
        {
            GL.MatrixMode(GL.Enums.MatrixMode.MODELVIEW);
            GL.LoadIdentity();
            Glu.LookAt(
                0.0, 5.0, 5.0,
                0.0, 0.0, 0.0,
                0.0, 1.0, 0.0
            );
            GL.Rotate(angle, 0.0f, 1.0f, 0.0f);
            angle += 0.5f;

            GL.Clear(GL.Enums.ClearBufferMask.COLOR_BUFFER_BIT | GL.Enums.ClearBufferMask.DEPTH_BUFFER_BIT);

            DrawCube();

            glControl.SwapBuffers();
        }

        #endregion

        #region GLControl.Resize event handler

        void glControl_Resize(object sender, EventArgs e)
        {
            OpenTK.GLControl c = sender as OpenTK.GLControl;

            if (c.ClientSize.Height == 0)
                c.ClientSize = new System.Drawing.Size(c.ClientSize.Width, 1);

            GL.Viewport(0, 0, c.ClientSize.Width, c.ClientSize.Height);

            double ratio = 0.0;
            ratio = c.ClientSize.Width / (double)c.ClientSize.Height;

            GL.MatrixMode(GL.Enums.MatrixMode.PROJECTION);
            GL.LoadIdentity();
            Glu.Perspective(45.0, ratio, 1.0, 64.0);
        }

        #endregion

        #region GLControl.KeyDown event handler

        void glControl_KeyDown(object sender, KeyEventArgs e)
        {
            switch (e.KeyData)
            {
                case Keys.Escape:
                    this.Close();
                    break;
            }
        }

        #endregion

        #region GLControl.Paint event handler

        void glControl_Paint(object sender, PaintEventArgs e)
        {
            Render();
        }

        #endregion

		#region private void DrawCube()

        private void DrawCube()
        {
            GL.Begin(GL.Enums.BeginMode.QUADS);

            GL.Color3(Color.Silver);
            GL.Vertex3(-1.0f, -1.0f, -1.0f);
            GL.Vertex3(-1.0f, 1.0f, -1.0f);
            GL.Vertex3(1.0f, 1.0f, -1.0f);
            GL.Vertex3(1.0f, -1.0f, -1.0f);

            GL.Color3(Color.Honeydew);
            GL.Vertex3(-1.0f, -1.0f, -1.0f);
            GL.Vertex3(1.0f, -1.0f, -1.0f);
            GL.Vertex3(1.0f, -1.0f, 1.0f);
            GL.Vertex3(-1.0f, -1.0f, 1.0f);

            GL.Color3(Color.Moccasin);

            GL.Vertex3(-1.0f, -1.0f, -1.0f);
            GL.Vertex3(-1.0f, -1.0f, 1.0f);
            GL.Vertex3(-1.0f, 1.0f, 1.0f);
            GL.Vertex3(-1.0f, 1.0f, -1.0f);

            GL.Color3(Color.IndianRed);
            GL.Vertex3(-1.0f, -1.0f, 1.0f);
            GL.Vertex3(1.0f, -1.0f, 1.0f);
            GL.Vertex3(1.0f, 1.0f, 1.0f);
            GL.Vertex3(-1.0f, 1.0f, 1.0f);

            GL.Color3(Color.PaleVioletRed);
            GL.Vertex3(-1.0f, 1.0f, -1.0f);
            GL.Vertex3(-1.0f, 1.0f, 1.0f);
            GL.Vertex3(1.0f, 1.0f, 1.0f);
            GL.Vertex3(1.0f, 1.0f, -1.0f);

            GL.Color3(Color.ForestGreen);
            GL.Vertex3(1.0f, -1.0f, -1.0f);
            GL.Vertex3(1.0f, 1.0f, -1.0f);
            GL.Vertex3(1.0f, 1.0f, 1.0f);
            GL.Vertex3(1.0f, -1.0f, 1.0f);

            GL.End();
        }

        #endregion
        
        #region IExample Members

        public void Launch()
        {
            
        }

        #endregion

        private void glControl_Layout(object sender, LayoutEventArgs e)
        {
            glControl_Resize(sender, EventArgs.Empty);
        }
    }
}