#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    Sun.ubo             //文件名
    Name    sun                 //在代码中的变量名
    Stage   Vertex,Fragment     //会引用的shader
}

#MaterialInstance

#VertexInput
vec3 Normal

#Vertex
Output
{
    vec3 Normal;
}

Code
{
    void main()
    {
        gl_Position=GetPosition3D();
    }
}

#Fragment
Output
{
    vec4 FragColor;
}

Code
{
    void main()
    {
        //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);

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

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

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

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

        //高光
        vec3 specular           =sun.specular*pow(saturate(dot(reflect_direction,view_direction)),gloss);

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