/*=============================================================================

  Project:   SharpImage
  Module:    siOpenGlRendererForm.cs
  Language:  C#
  Author:    Dan Mueller
  Date:      $Date: 2007-07-06 10:57:00 +1000 (Fri, 06 Jul 2007) $
  Revision:  $Revision: 2 $

  Copyright (c) Queensland University of Technology (QUT) 2007.
  All rights reserved.

  This software is distributed WITHOUT ANY WARRANTY; without even
  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  PURPOSE.  See the above copyright notices for more information.
  
=============================================================================*/

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

using Tao.OpenGl;
using Tao.FreeGlut;
using Tao.Platform.Windows;

namespace SharpImage.Rendering
{
    public partial class siOpenGlRendererForm : siRendererForm
    {
        bool HasSetSizeFirstTime = false;
        bool SuppressResizeEvent = false;
        
        /// <summary>
        /// Default constructor.
        /// </summary>
        public siOpenGlRendererForm() : base(new SimpleOpenGlControl())
        {
            // Call the designer code
            InitializeComponent();
        }

        /// <summary>
        /// Deconstructor.
        /// </summary>
        ~siOpenGlRendererForm()
        {
            if (this.RenderingControl != null)
            {
                (this.RenderingControl as SimpleOpenGlControl).DestroyContexts();
                (this.RenderingControl as SimpleOpenGlControl).Dispose();
                this.RenderingControl = null;
            }
        }

        /// <summary>
        /// Force the Control to repaint.
        /// </summary>
        public override void Repaint()
        {
            if (this.Renderer != null)
            {
                this.Renderer.RaiseModified();
                (this.RenderingControl as SimpleOpenGlControl).Invalidate();
                (this.RenderingControl as SimpleOpenGlControl).Refresh();
                //(this.RenderingControl as SimpleOpenGlControl).SwapBuffers();
            }
        }

        /// <summary>
        /// Initialise the RendererForm.
        /// </summary>
        public override void Initialise(siRenderer renderer)
        {
            base.Initialise(renderer);
            (this.RenderingControl as SimpleOpenGlControl).AutoCheckErrors = false;
            (this.RenderingControl as SimpleOpenGlControl).AutoFinish = false;
            (this.RenderingControl as SimpleOpenGlControl).AutoMakeCurrent = true;
            (this.RenderingControl as SimpleOpenGlControl).AutoSwapBuffers = true;
            (this.RenderingControl as SimpleOpenGlControl).AccumBits = ((System.Byte)(0));
            (this.RenderingControl as SimpleOpenGlControl).ColorBits = ((System.Byte)(32));
            (this.RenderingControl as SimpleOpenGlControl).DepthBits = ((System.Byte)(16));
            (this.RenderingControl as SimpleOpenGlControl).StencilBits = ((System.Byte)(0));
            (this.RenderingControl as SimpleOpenGlControl).InitializeContexts();
            this.Renderer.RaiseModified();
        }

        /// <summary>
        /// Get/set the size of the renderable area.
        /// </summary>
        public override Size ViewportSize
        {
            get { return base.ViewportSize; }
            set 
            {
                this.SuppressResizeEvent = true;
                base.ViewportSize = value;
                this.HasSetSizeFirstTime = false;
                this.SuppressResizeEvent = false;
                this.ForceResize();
            }
        }

        protected override void OnResize(EventArgs e)
        {
            // Check if the resize event is allowed
            if (this.SuppressResizeEvent)
                return;

            // Run the base
            base.OnResize(e);

            // Check we have been initialised
            if (!this.IsInitialised)
                return;

            if (!this.HasSetSizeFirstTime)
            {
                // Set window width/height values for the first time
                this.Renderer.Metadata["RenderingControlWidth"] = this.RenderingControl.ClientSize.Width;
                this.Renderer.Metadata["RenderingControlHeight"] = this.RenderingControl.ClientSize.Height;
                this.HasSetSizeFirstTime = true;
            }

            if (!this.Renderer.ContainsMetadata("FrustrumLeft",
                                                "FrustrumRight",
                                                "FrustrumBottom",
                                                "FrustrumTop",
                                                "FrustrumFront",
                                                "FrustrumBack",
                                                "RenderingControlWidth",
                                                "RenderingControlHeight"))
            {
                return;
            }

            // Change Viewport
            Gl.glViewport(0, 0, this.RenderingControl.ClientSize.Width, this.RenderingControl.ClientSize.Height);

            // Change Frustum
            Gl.glMatrixMode(Gl.GL_PROJECTION);
            Gl.glLoadIdentity();

            double frustrumLeft = (double)this.Renderer.Metadata["FrustrumLeft"];
            double frustrumRight = (double)this.Renderer.Metadata["FrustrumRight"];
            double frustrumBottom = (double)this.Renderer.Metadata["FrustrumBottom"];
            double frustrumTop = (double)this.Renderer.Metadata["FrustrumTop"];

            frustrumLeft *= (double)this.RenderingControl.ClientSize.Width / (double)(int)this.Renderer.Metadata["RenderingControlWidth"];
            frustrumRight *= (double)this.RenderingControl.ClientSize.Width / (double)(int)this.Renderer.Metadata["RenderingControlWidth"];
            frustrumBottom *= (double)this.RenderingControl.ClientSize.Height / (double)(int)this.Renderer.Metadata["RenderingControlHeight"];
            frustrumTop *= (double)this.RenderingControl.ClientSize.Height / (double)(int)this.Renderer.Metadata["RenderingControlHeight"];

            // HACK: We currently assume the type of renderer is siVolumeRenderer
            // TODO: TOFIX: Get rid of the metadata stuff, add a concrete hierarchy
            siVolumeRenderer renderer = this.Renderer as siVolumeRenderer;
            renderer.Properties.FrustrumLeft = frustrumLeft;
            renderer.Properties.FrustrumRight = frustrumRight;
            renderer.Properties.FrustrumBottom = frustrumBottom;
            renderer.Properties.FrustrumTop = frustrumTop;

            Gl.glFrustum(renderer.Properties.FrustrumLeft,
                         renderer.Properties.FrustrumRight,
                         renderer.Properties.FrustrumBottom,
                         renderer.Properties.FrustrumTop,
                         renderer.Properties.FrustrumFront,
                         renderer.Properties.FrustrumBack);

            Gl.glMatrixMode(Gl.GL_MODELVIEW);

            // Set new width/height values
            this.Renderer.Metadata["RenderingControlWidth"] = this.RenderingControl.ClientSize.Width;
            this.Renderer.Metadata["RenderingControlHeight"] = this.RenderingControl.ClientSize.Height;

            // Force a repaint
            this.Repaint();
        }
    }
}