alphamodifier.h

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

    The Mezzanine Engine is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
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    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with The Mezzanine Engine.  If not, see <http://www.gnu.org/licenses/>.
*/
/* The original authors have included a copy of the license specified above in the
   'Docs' folder. See 'gpl.txt'
*/
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   However there are some practical restrictions, so if your project involves
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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
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 -----------------------------------------------------------------------------
 */
#ifndef _graphicsproceduralalphamodifier_h
#define _graphicsproceduralalphamodifier_h

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

namespace Mezzanine
{
    namespace Graphics
    {
        namespace Procedural
        {
            ///////////////////////////////////////////////////////////////////////////////
            /// @brief A modifier that will replace all pixels with "White Smoke" corresponding to the intensity of the extracted colour and the source alpha channel.
            /// @details The extract colour isn't used explicitly, instead each channel (except for the alpha channel) is multiplied by the corresponding channel of the
            /// source pixel.  The Alpha channel value is then factored in unaltered by the ExtractColour member.  Setting an alpha value to the ExtractColour has no effect.
            ///////////////////////////////////////
            class MEZZ_LIB AlphaModifier : public TextureModifier
            {
            protected:
                /// @internal
                /// @brief The amount from each colour channel to be extracted from the source texture.
                ColourValue ExtractColour;
            public:
                /// @brief Blank constructor.
                AlphaModifier();
                /// @brief Class destructor.
                virtual ~AlphaModifier();

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

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

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

                /// @brief Sets the amount of colour to extract for each colour channel.
                /// @param Extract The amount from each colour channel to be extracted from the source texture.
                /// @return Returns a reference to this.
                AlphaModifier& SetExtractColour(const ColourValue& Extract);
            };//AlphaModifier
        }//Procedural
    }//Graphics
}//Mezzanine

#endif