UnityShader 学习笔记 8 处理阴影和光照衰减

同时处理阴影和光照衰减的Shader

• 源码：

Shader \"_MyShader/6_Light/2_ShadowAndAttenuation\"

{

    Properties

    {

        _DiffuseColor (\"DiffuseColor\",COLOR) =(1,1,1,1)

        _SpecularColor (\"SpecularColor\",COLOR) =(1,1,1,1)

        _SpecularRange (\"SpecularRange\",Range(5,100)) = 20

    }

    SubShader

    {

        Pass

        {

            Tags{\"LightMode\" = \"Forward \"}

            CGPROGRAM

            #pragma vertex vert

            #pragma fragment frag

            #pragma multi_compile_fwd 

            

            #include \"Lighting.cginc\"

            #include \"AutoLight.cginc\"





            fixed4 _DiffuseColor;

            fixed4 _SpecularColor;

            float _SpecularRange;



            struct a2v {

                float4 vertex:POSITION;

                float3 normal:NORMAL;

            };



            struct v2f{

                float4 pos:SV_POSITION;

                fixed3 worldNormalDir:POSITION1;

                fixed3 worldLightDir:POSITION2;

                half3 reflectDir:POSITION3;

                fixed3 worldViewDir:POSITION4;

                //Blinn-Phong

                fixed3 blinn_Phong_Dir:POSITION5;

                //声明阴影坐标

                float4 worldPos:POSITION6;

                SHADOW_COORDS(2)

            };



            v2f vert(a2v v){

                v2f o;

                o.pos=mul(UNITY_MATRIX_MVP,v.vertex);



                o.worldPos = mul(_ 2World,v.vertex);



                o.worldLightDir = normalize(_WorldSpaceLightPos0);

                o.worldNormalDir = normalize(mul(v.normal,(float3x3)_World2 ));



                //计算反射向量

                o.reflectDir = normalize(reflect(-o.worldLightDir,o.worldNormalDir));

                //计算视角向量

                o.worldViewDir = normalize(_WorldSpaceCameraPos - mul(_ 2World,v.vertex));



                //Blinn-Phong

                o.blinn_Phong_Dir = normalize(o.worldLightDir + o.worldViewDir);



                //计算并输出阴影坐标

                TRANSFER_SHADOW(o);



                return o;

            }



            fixed4 frag(v2f i):SV_Target{

                UNITY_LIGHT_ATTENUATION(atten,i,i.worldPos);



                //漫反射阶段

                fixed3 ambientColor=UNITY_LIGHTMODEL_AMBIENT;



                fixed3 diffuseColor = _LightColor0 * _DiffuseColor*saturate(dot(i.worldNormalDir,i.worldLightDir));



                //高光阶段

                fixed3 specularColor = _LightColor0 * _SpecularColor * pow(saturate(dot(i.reflectDir,i.worldViewDir)),_SpecularRange);

                //Blinn-Phong光照

                //fixed3 specularColor = _LightColor0 * _SpecularColor * pow(saturate(dot(i.worldNormalDir,i.blinn_Phong_Dir)),_SpecularRange);

                

                fixed4 col = fixed4(ambientColor + (diffuseColor + specularColor) * atten,1);

                return col;

            }



            

            ENDCG

        }



        //-----------------------------------------------------------------------------------------------------



        Pass

        {

            Tags{\"LightMode\" = \"ForwardAdd\"}

            Blend One One



            CGPROGRAM

            #pragma vertex vert

            #pragma fragment frag

            #pragma multi_compile_fwdadd_fullshadows

            

            #include \"Lighting.cginc\"

            #include \"AutoLight.cginc\"





            fixed4 _DiffuseColor;

            fixed4 _SpecularColor;

            float _SpecularRange;



            struct a2v {

                float4 vertex:POSITION;

                float3 normal:NORMAL;

            };



            struct v2f{

                float4 pos:SV_POSITION;

                fixed3 worldNormalDir:POSITION1;

                fixed3 worldLightDir:POSITION2;

                half3 reflectDir:POSITION3;

                fixed3 worldViewDir:POSITION4;

                //Blinn-Phong

                fixed3 blinn_Phong_Dir:POSITION5;

                float4 worldPos:POSITION6;

                SHADOW_COORDS(2)

            };



            v2f vert(a2v v){

                v2f o;

                o.pos=mul(UNITY_MATRIX_MVP,v.vertex);



                o.worldPos = mul(_ 2World,v.vertex);

                

            #ifdef USING_DIRECTIONAL_LIGHT

                o.worldLightDir = normalize(_WorldSpaceLightPos0);

            #else

                o.worldLightDir = normalize(_WorldSpaceLightPos0 - o.worldPos);

            #endif



                o.worldNormalDir = normalize(mul(v.normal,(float3x3)_World2 ));



                //计算反射向量

                o.reflectDir = normalize(reflect(-o.worldLightDir,o.worldNormalDir));

                //计算视角向量

                o.worldViewDir = normalize(_WorldSpaceCameraPos - mul(_ 2World,v.vertex));



                //Blinn-Phong

                o.blinn_Phong_Dir = normalize(o.worldLightDir + o.worldViewDir);



                TRANSFER_SHADOW(o);



                return o;

            }



            fixed4 frag(v2f i):SV_Target{

                UNITY_LIGHT_ATTENUATION(atten, i, i.worldPos.xyz)



                //漫反射阶段

                //fixed3 ambientColor=UNITY_LIGHTMODEL_AMBIENT;



                fixed3 diffuseColor = _LightColor0 * _DiffuseColor*saturate(dot(i.worldNormalDir,i.worldLightDir));



                //高光阶段

                fixed3 specularColor = _LightColor0 * _SpecularColor * pow(saturate(dot(i.reflectDir,i.worldViewDir)),_SpecularRange);

                //Blinn-Phong光照

                //fixed3 specularColor = _LightColor0 * _SpecularColor * pow(saturate(dot(i.worldNormalDir,i.blinn_Phong_Dir)),_SpecularRange);





                fixed4 col = fixed4((diffuseColor + specularColor) * atten,1);

                return col;

            }



            

            ENDCG

        }



    }

    FallBack \"VertexLit\"

}