PlanarShadow.shader

Shader "LX/PlanarShadow"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
    }
    SubShader
    {
        Tags
        {
            "RenderType"="Opaque"
        }

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
                float3 normal : NORMAL;
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
                float3 worldNormal : TEXCOORD1;
                float3 worldPos : TEXCOORD2;
            };

            sampler2D _MainTex;
            float4 _MainTex_ST;

            v2f vert(appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                o.worldNormal = UnityObjectToWorldNormal(v.normal);
                o.worldPos = mul(unity_ObjectToWorld, v.vertex);
                return o;
            }

            fixed4 frag(v2f i) : SV_Target
            {
                fixed4 col = tex2D(_MainTex, i.uv);
                float3 worldNormal = normalize(i.worldNormal);
                float3 worldLightDir = normalize(UnityWorldSpaceLightDir(i.worldPos));
                fixed diffuse = saturate(dot(worldNormal, worldLightDir));
                return col * diffuse;
            }
            ENDCG
        }

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
                float3 normal : NORMAL;
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
                float3 worldNormal : TEXCOORD1;
                float3 worldPos : TEXCOORD2;
            };

            sampler2D _MainTex;
            float4 _MainTex_ST;
            float _ShadowLayer;
            float4 _ShadowColor;

            v2f vert(appdata v)
            {
                v2f o;
                float3 worldPos = mul(unity_ObjectToWorld, v.vertex);
                worldPos.y = _ShadowLayer;
                o.vertex = mul(UNITY_MATRIX_VP, float4(worldPos, 1.0));
                return o;
            }

            fixed4 frag(v2f i) : SV_Target
            {
                return _ShadowColor;
            }
            ENDCG
        }
    }
}