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IMG_Color.h

#ifndef _H_IMG_Color
#define _H_IMG_Color

class IMG_ColorRGBA;


class IMG_ColorRGB {
public:
        IMG_ColorRGB(float r=0, float g=0, float b=0)
                : m_r(r), m_g(g), m_b(b) {}

        IMG_ColorRGB(const IMG_ColorRGB& c)
                : m_r(c.m_r), m_g(c.m_g), m_b(c.m_b) {}

        inline IMG_ColorRGB(const IMG_ColorRGBA& c);

        float m_r;
        float m_g;
        float m_b;
};



class IMG_ColorRGBA {
public:
        IMG_ColorRGBA(float r=0, float g=0, float b=0, float a=0)
                : m_r(r), m_g(g), m_b(b), m_a(a) {}

        IMG_ColorRGBA(const IMG_ColorRGBA& c)
                : m_r(c.m_r), m_g(c.m_g), m_b(c.m_b), m_a(c.m_a) {}

        IMG_ColorRGBA(const IMG_ColorRGB& c)
                : m_r(c.m_r), m_g(c.m_g), m_b(c.m_b), m_a(0) {}

        inline void     blendColor(const IMG_ColorRGBA& c);

        float m_r;
        float m_g;
        float m_b;
        float m_a;
};

inline IMG_ColorRGB::IMG_ColorRGB(const IMG_ColorRGBA& c)
        : m_r(c.m_r), m_g(c.m_g), m_b(c.m_b) {}

inline void     IMG_ColorRGBA::blendColor(const IMG_ColorRGBA& c)
{
        float r1 = 1 - c.m_a; // The reverse of alpha
#if IMG_REVERSED_ALPHA
        m_r = c.m_a * m_r + r1 * c.m_r;
        m_g = c.m_a * m_g + r1 * c.m_g;
        m_b = c.m_a * m_b + r1 * c.m_b;
#else
        m_r = r1 * m_r + c.m_a * c.m_r;
        m_g = r1 * m_g + c.m_a * c.m_g;
        m_b = r1 * m_b + c.m_a * c.m_b;
#endif
}


#endif // _H_IMG_Color

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