VGACanvas.cs

using System;
using System.Collections.Generic;
using System.Text;
using Cosmos.HAL;
using System.Drawing;
using static Cosmos.HAL.VGADriver;

namespace Cosmos.System.Graphics
{
    /// <summary>
    /// VGACanvas class. Used to control screen.
    /// </summary>
    public class VGACanvas : Canvas
    {
        /// <summary>
        /// Private boolean whether VGA graphics mode is enabled or not
        /// </summary>
        bool _Enabled;
        private Mode _Mode;

        /// <summary>
        /// The HAL VGA driver
        /// </summary>
        private readonly VGADriver _VGADriver;

        /// <summary>
        /// VGA graphics mode Canvas constructor - see Canvas.cs
        /// </summary>
        /// <param name="aMode"></param>
        public VGACanvas(Mode aMode) : base()
        {
            Global.mDebugger.Send("Creating VGACanvas with mode");
            _VGADriver = new VGADriver();
            _VGADriver.SetGraphicsMode(ModeToScreenSize(aMode), (VGADriver.ColorDepth)(int)aMode.ColorDepth);
            Mode = aMode;
            Enabled = true;
        }

        /// <summary>
        /// Creates a VGA graphics mode with the default mode
        /// </summary>
        public VGACanvas() : base()
        {
            Enabled = true;
            Mode = DefaultGraphicMode;
            Global.mDebugger.Send("Creating VGACanvas with standard mode");
            _VGADriver = new VGADriver();
            _VGADriver.SetGraphicsMode(ModeToScreenSize(DefaultGraphicMode), (VGADriver.ColorDepth)(int)DefaultGraphicMode.ColorDepth);
        }

        /// <summary>
        /// Name of the backend
        /// </summary>
        public override string Name() => "VGACanvas";

        /// <summary>
        /// Gets or sets the VGA graphics mode
        /// </summary>
        public override Mode Mode
        {
            get => _Mode; set
            {
                _VGADriver.SetGraphicsMode(ModeToScreenSize(_Mode), (VGADriver.ColorDepth)(int)_Mode.ColorDepth);
                _Mode = value;
            }
        }

        /// <summary>
        /// Clears the screen of all pixels
        /// </summary>
        /// <param name="aColor"></param>
        public override void Clear(int aColor)
        {
            _VGADriver.DrawFilledRectangle(0, 0, _VGADriver.PixelWidth, _VGADriver.PixelHeight, (uint)aColor);
        }

        /// <summary>
        /// Clears the screen of all pixels
        /// </summary>
        /// <param name="aColor"></param>
        public override void Clear(Color aColor)
        {
            var paletteIndex = _VGADriver.GetClosestColorInPalette(aColor);
            _VGADriver.DrawFilledRectangle(0, 0, _VGADriver.PixelWidth, _VGADriver.PixelHeight, paletteIndex);
        }

        /// <summary>
        /// Disables VGA graphics mode, parent method returns to 80x25 text mode
        /// </summary>
        public override void Disable()
        {
            if (Enabled)
            {
                VGAScreen.SetTextMode(TextSize.Size80x25);
                Enabled = false;
            }
        }

        /// <summary>
        /// Draws an array of colors, specifiying X and Y coords
        /// </summary>
        /// <param name="aColors"></param>
        /// <param name="aX"></param>
        /// <param name="aY"></param>
        /// <param name="aWidth"></param>
        /// <param name="aHeight"></param>
        public override void DrawArray(Color[] aColors, int aX, int aY, int aWidth, int aHeight)
        {
            throw new NotImplementedException();
        }

        /// <summary>
        /// Draws a filled rectangle
        /// </summary>
        /// <param name="aColor"></param>
        /// <param name="aXStart"></param>
        /// <param name="aYStart"></param>
        /// <param name="aWidth"></param>
        /// <param name="aHeight"></param>
        public override void DrawFilledRectangle(Color aColor, int aXStart, int aYStart, int aWidth, int aHeight)
        {
            _VGADriver.DrawFilledRectangle(aXStart, aYStart, aWidth, aHeight, _VGADriver.GetClosestColorInPalette(aColor));
        }

        /// <summary>
        /// Draws a point
        /// </summary>
        /// <param name="aColor"></param>
        /// <param name="aX"></param>
        /// <param name="aY"></param>
        public override void DrawPoint(Color aColor, int aX, int aY)
        {
            _VGADriver.SetPixel((uint)aX, (uint)aY, aColor);
        }

        /// <summary>
        /// Draws a point
        /// </summary>
        /// <param name="aColor"></param>
        /// <param name="aX"></param>
        /// <param name="aY"></param>
        public void DrawPoint(uint aColor, int aX, int aY)
        {
            _VGADriver.SetPixel((uint)aX, (uint)aY, aColor);
        }

        /// <summary>
        /// Draws a point
        /// </summary>
        /// <param name="aColor"></param>
        /// <param name="aX"></param>
        /// <param name="aY"></param>
        public override void DrawPoint(Color aColor, float aX, float aY)
        {
            throw new NotImplementedException();
        }

        /// <summary>
        /// List of available resolutions
        /// </summary>
        private static readonly List<Mode> _AvailableModes = new List<Mode>
        {
            new Mode(640, 480, ColorDepth.ColorDepth4),
            new Mode(720, 480, ColorDepth.ColorDepth4),
            new Mode(320, 200, ColorDepth.ColorDepth8)
        };

        public override List<Mode> AvailableModes
        {
            get
            {
                return _AvailableModes;
            }
        }

        /// <summary>
        /// Retrieves the RGB value of a specified pixel
        /// </summary>
        /// <param name="aX"></param>
        /// <param name="aY"></param>
        /// <returns></returns>
        public override Color GetPointColor(int aX, int aY)
        {
            return Color.FromArgb((int)_VGADriver.GetPixel((uint)aX, (uint)aY));
        }

        /// <summary>
        /// The default graphics mode
        /// </summary>
        public override Mode DefaultGraphicMode => new Mode(640, 480, ColorDepth.ColorDepth4);

        /// <summary>
        /// Boolean value whether VGA is in graphics mode or not
        /// </summary>
        public bool Enabled { get => _Enabled; private set => _Enabled = value; }

        private ScreenSize ModeToScreenSize(Mode aMode)
        {
            if (aMode.Width == 320 && aMode.Height == 200)
            {
                return ScreenSize.Size320x200;
            }
            else if (aMode.Width == 640 && aMode.Height == 480)
            {
                return ScreenSize.Size640x480;
            }
            else if (aMode.Width == 720 && aMode.Height == 480)
            {
                return ScreenSize.Size720x480;
            }
            else
            {
                throw new NotImplementedException();
            }
        }

        public override void Display()
        {

        }
    }
}