#ifndef HGL_GRAPH_LIGHT_INCLUDE
#define HGL_GRAPH_LIGHT_INCLUDE

#include<hgl/math/Math.h>
#include<hgl/color/Color4f.h>
namespace hgl
{
    namespace graph
    {
        enum LightMode
        {
            lmNone = 0,

            lmVertex,
            lmPixel,

            lmEnd
        };//enum LightMode

        /**
         * 光源类型
         */
        enum LightType
        {
            ltNone=0,           ///<起始定义，无意义

            ltSunLight,         ///<太阳光

            ltPoint,            ///<点光源
            ltDirection,        ///<方向光
            ltSpot,             ///<聚光灯
            ltInfiniteSpotLight,///<无尽聚光灯

            ltAreaQuad,         ///<四边形面光源

            ltEnd               ///<结束定义，无意义
        };//enum LightType

        /**
         * 灯光
         */
        struct Light
        {
            LightType   type;           ///<光源类型

            bool        enabled;        ///<是否开启

            Color4f     ambient;        ///<环境光
            Color4f     specular;       ///<镜面光
            Color4f     diffuse;        ///<漫反射
        };//struct Light

        /**
         * 太阳光
         */
        struct SunLight :public Light
        {
            Vector3f    direction;
        };

        /**
         * 方向光
         */
        struct DirectionLight:public Light
        {
            Vector3f    direction;              ///<方向

            float       nDotVP;                 ///<normal . light direction
            float       nDotHV;                 ///<normal . half vector
        };//struct DirectionLight

        /**
         * 点光源
         */
        struct PointLight:public Light
        {
            Vector3f    position;               ///<光源位置

            Vector3f    attenuation;            ///<constant,linear,quadratic
        };//struct PointLight

        /**
         * 聚光灯
         */
        struct SpotLight:public Light
        {
            Vector3f    position;               ///<位置
            Vector3f    direction;              ///<方向
            Vector3f    attenuation;            ///<constant,linear,quadratic

            float       coscutoff;
            float       exponent;
        };//struct SpotLight

        /**
         * 无尽聚光灯
         */
        struct InfiniteSpotLight:public Light
        {
            Vector3f    position;
            Vector3f    direction;
            Vector3f    exponent;
        };//struct InfiniteSpotLight
    }//namespace graph
}//namespace hgl
#endif//HGL_GRAPH_LIGHT_INCLUDE