channelmodifier.h

// © Copyright 2010 - 2016 BlackTopp Studios Inc.
/* This file is part of The Mezzanine Engine.

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*/
/* The original authors have included a copy of the license specified above in the
   'Docs' folder. See 'gpl.txt'
*/
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/*
 -----------------------------------------------------------------------------
 This source file is part of ogre-procedural

 For the latest info, see http://code.google.com/p/ogre-procedural/

 Copyright (c) 2010-2013 Michael Broutin

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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 THE SOFTWARE.
 -----------------------------------------------------------------------------
 */
#ifndef _graphicsproceduralchannelmodifier_h
#define _graphicsproceduralchannelmodifier_h

#include "Graphics/Procedural/Texture/texturemodifier.h"

namespace Mezzanine
{
    namespace Graphics
    {
        namespace Procedural
        {
            ///////////////////////////////////////////////////////////////////////////////
            /// @brief A modifier that will zero out selected colour channels or produce a grey version of the provided texture.
            /// @details
            ///////////////////////////////////////
            class MEZZ_LIB ChannelModifier : public TextureModifier
            {
            public:
                /// @brief An enum describing the operation to be taken.
                enum ChannelSelect
                {
                    CS_Red     = 1,     ///< Zero the red channel for each pixel in the texture.  Ignored if "CS_Gray" is selected.
                    CS_Green   = 2,     ///< Zero the green channel for each pixel in the texture.  Ignored if "CS_Gray" is selected.
                    CS_Blue    = 4,     ///< Zero the blue channel for each pixel in the texture.  Ignored if "CS_Gray" is selected.
                    CS_Alpha   = 8,     ///< Zero the alpha channel for each pixel in the texture.  Warning: This will make the texture disappear.  Ignored if "CS_Gray" is selected.
                    CS_Gray    = 16     ///< Generate a black and white version of the image by averaging channel intensities.
                };
            protected:
                /// @internal
                /// @brief A bitfield containing the operation to be performed.
                Whole ChannelOp;
            public:
                /// @brief Blank constructor.
                ChannelModifier();
                /// @brief Class destructor.
                virtual ~ChannelModifier();

                ///////////////////////////////////////////////////////////////////////////////
                // Utility

                /// @copydoc TextureModifier::Modify(TextureBuffer&)
                virtual void Modify(TextureBuffer& Buffer);
                /// @copydoc TextureModifier::GetName() const
                virtual String GetName() const;

                ///////////////////////////////////////////////////////////////////////////////
                // Configuration

                /// @brief Sets the channels that are to be zero'd or if the modifier should generate a gray texture.
                /// @param Op A bitfield containing the operation to be performed.  Initial Value: CS_Gray.
                /// @return Returns a reference to this.
                ChannelModifier& SetSelection(const Whole Op);
            };//ChannelModifier
        }//Procedural
    }//Graphics
}//Mezzanine

#endif