transparent_colormixer.h

// Description: TransparentColorMixer
// Detail: Linearly interpolates between background and texture
// Documentation: colormixers.txt

#ifndef PASTELGFX_TRANSPARENT_COLORMIXER_H
#define PASTELGFX_TRANSPARENT_COLORMIXER_H

#include "pastel/gfx/color/colormixer.h"

#include "pastel/sys/mytypes.h"

namespace Pastel
{

    template <typename Type>
    class TransparentColorMixer
        : public ColorMixer<Type>
    {
    public:
        TransparentColorMixer()
            : opaqueness_(1)
        {
        }

        explicit TransparentColorMixer(
            real opaqueness)
            : opaqueness_(opaqueness)
        {
        }

        virtual ~TransparentColorMixer()
        {
        }

        virtual Type operator()(
            const Type& background,
            const Type& texture) const
        {
            return (1 - opaqueness_) * background +
                opaqueness_ * texture;
        }

        void setOpaqueness(real opaqueness)
        {
            opaqueness_ = opaqueness;
        }

        real opaqueness() const
        {
            return opaqueness_;
        }

    private:
        real opaqueness_;
    };

    template <typename Type>
    TransparentColorMixer<Type> transparentColorMixer(real opaqueness)
    {
        return TransparentColorMixer<Type>(opaqueness);
    }

}

#endif