#Material
Name        BlinnPhong+HalfLambert shading model only color
Reference   https://zhuanlan.zhihu.com/p/442023993
Base        Std3D/BlinnPhong

//某些Require并不真的存在.ubo文件，写成一行一个是为了方便未来改成带路径的
Require     LocalToWorld
Require     Camera

define      HAVE_SPECULAR   off     //默认不定义HAVE_SPECULAR

UBO
{
    File    BlinnPhongSun.ubo   //文件名,如果/开头表示从ShaderLibrary根目录开始，没有则表示同一目录
    Struct  BlinnPhongSun       //结构名称
    Name    sun                 //在代码中的变量名
    Stage   Fragment            //会引用的shader
    Set     Global              //Descriptor Set
}

#MaterialInstance
Length 16
Stage  Fragment
Code
{
    vec3 Color;
    float Gloss;
}

#VertexInput
vec3 Normal

#Vertex
Output
{
    vec4 Position;
    vec3 Normal;
}

Code
{
    void main()
    {
        HandoverMI();

        Output.Normal=Normal;
        Output.Position=GetPosition3D();
        gl_Position=Output.Position;
    }
}

#Fragment
Output
{
    vec4 FragColor;
}

Code
{
    void main()
    {
        MaterialInstance mi=GetMI();

        //将法线归一化
        vec3 world_normal           =normalize(Input.Normal);

        //对世界坐标下的灯光方法归一化
        vec3 world_light_direction  =normalize(sun.direction.xyz);

        //点乘法线和光照
        vec3 diffuse                =vec3(0.5)*dot(world_light_direction.xyz,world_normal)+vec3(0.5);

        //直接光颜色
        vec3 direct_color           =diffuse*sun.color.rgb*mi.Color.rgb;

//    #ifndef HAVE_SPECULAR
//        FragColor=vec4(direct_color,1.0);
//     #else
        //归一代视角方向
        vec3 view_direction     =normalize(camera.pos-Input.Position.xyz);

        //世界坐标下的反射光方向
        vec3 reflect_direction  =normalize(reflect(-world_light_direction,world_normal));

        //高光
        float specular           =pow(clamp(dot(reflect_direction,view_direction),0.0,1.0),mi.Gloss);

        FragColor               =vec4(direct_color+vec3(specular),1.0);
//     #endif//HAVE_SPECULAR
    }
}