Source/OpenTK/Graphics/ColorFormat.cs

#region --- License ---
/* Licensed under the MIT/X11 license.
 * Copyright (c) 2006-2008 the OpenTK Team.
 * This notice may not be removed from any source distribution.
 * See license.txt for licensing detailed licensing details.
 */
#endregion

using System;
using System.Collections.Generic;
using System.Text;

namespace OpenTK.Graphics
{
    public struct ColorFormat
    {
        byte red, green, blue, alpha;
        bool isIndexed;
        int bitsPerPixel;

        #region --- Constructors ---

        public ColorFormat(int bpp)
        {
            if (bpp < 0)
                throw new ArgumentOutOfRangeException("bpp", "Must be greater or equal to zero.");
            red = green = blue = alpha = 0;
            bitsPerPixel = bpp;
            isIndexed = false;

            switch (bpp)
            {
                case 32:
                    Red = Green = Blue = Alpha = 8;
                    break;
                case 24:
                    Red = Green = Blue = 8;
                    break;
                case 16:
                    Red = Blue = 5;
                    Green = 6;
                    break;
                case 15:
                    Red = Green = Blue = 5;
                    break;
                case 8:
                    Red = Green = 3;
                    Blue = 2;
                    IsIndexed = true;
                    break;
                case 4:
                    Red = Green = 2;
                    Blue = 1;
                    IsIndexed = true;
                    break;
                case 1:
                    IsIndexed = true;
                    break;
                default:
                    Red = Blue = Alpha = (byte)(bpp / 4);
                    Green = (byte)((bpp / 4) + (bpp % 4));
                    break;
            }
        }

        public ColorFormat(int red, int green, int blue, int alpha)
        {
            if (red < 0 || green < 0 || blue < 0 || alpha < 0)
                throw new ArgumentOutOfRangeException("Arguments must be greater or equal to zero.");
            this.red = (byte)red;
            this.green = (byte)green;
            this.blue = (byte)blue;
            this.alpha = (byte)alpha;
            this.bitsPerPixel = red + green + blue + alpha;
            this.isIndexed = false;
            if (this.bitsPerPixel < 15 && this.bitsPerPixel != 0)
                this.isIndexed = true;
        }

        #endregion

        #region --- Public Methods ---

        public int Red { get { return red; } private set { red = (byte)value; } }
        public int Green { get { return green; } private set { green = (byte)value; } }
        public int Blue { get { return blue; } private set { blue = (byte)value; } }
        public int Alpha { get { return alpha; } private set { alpha = (byte)value; } }
        public bool IsIndexed { get { return isIndexed; } private set { isIndexed = value; } }
        public int BitsPerPixel { get { return bitsPerPixel; } private set { bitsPerPixel = value; } }

        #endregion

        #region --- Operator Overloads ---

        public static implicit operator ColorFormat(int bpp)
        {
            return new ColorFormat(bpp);
        }

        //public static implicit operator int(ColorFormat mode)
        //{
        //    return mode.BitsPerPixel;
        //}

        #endregion

        #region --- Overrides ---

        public override bool Equals(object obj)
        {
            return (obj is ColorFormat) ? (this == (ColorFormat)obj) : false;
        }

        public static bool operator ==(ColorFormat left, ColorFormat right)
        {
            if ((object)left == (object)null && (object)right != (object)null ||
                (object)left != (object)null && (object)right == (object)null)
                return false;

            if ((object)left == (object)null && (object)right == (object)null)
                return true;

            return left.Red == right.Red &&
                   left.Green == right.Green &&
                   left.Blue == right.Blue &&
                   left.Alpha == right.Alpha;
        }

        public static bool operator !=(ColorFormat left, ColorFormat right)
        {
            return !(left == right);
        }

        public override int GetHashCode()
        {
            return Red ^ Green ^ Blue ^ Alpha;
        }

        public override string ToString()
        {
            return string.Format("{0} ({1})", BitsPerPixel, (IsIndexed ? " indexed" : Red.ToString() + Green.ToString() + Blue.ToString() + Alpha.ToString()));
        }

        #endregion
    }
}

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