// Unity built-in shader source. Copyright (c) 2016 Unity Technologies. MIT license (see license.txt)

    Shader "Sprites/DefaultShadow"
    {
        Properties
        {
            [PerRendererData] _MainTex ("Sprite Texture", 2D) = "white" {}
            _Color ("Tint", Color) = (1,1,1,1)
            [MaterialToggle] PixelSnap ("Pixel snap", Float) = 0
            [HideInInspector] _RendererColor ("RendererColor", Color) = (1,1,1,1)
            [HideInInspector] _Flip ("Flip", Vector) = (1,1,1,1)
            [PerRendererData] _AlphaTex ("External Alpha", 2D) = "white" {}
            [PerRendererData] _EnableExternalAlpha ("Enable External Alpha", Float) = 0
            _ShadowOffset("Shadow Offset", Vector) = (4,4,0,0)
            _ShadowColor("Shadow Color", Color) = (0.02, -0.02, 0, 0)
        }

        SubShader
        {
            Tags
            {
                "Queue"="Transparent"
                "IgnoreProjector"="True"
                "RenderType"="Transparent"
                "PreviewType"="Plane"
                "CanUseSpriteAtlas"="True"
            }

            Cull Off
            Lighting Off
            ZWrite Off
            Blend One OneMinusSrcAlpha

            Pass
            {
            CGPROGRAM
                #pragma vertex SpriteVertShadow
                #pragma fragment SpriteFragShadow
                #pragma target 2.0
                #pragma multi_compile_instancing
                #pragma multi_compile _ PIXELSNAP_ON
                #pragma multi_compile _ ETC1_EXTERNAL_ALPHA
                #include "UnitySprites.cginc"

                fixed4 _ShadowColor;
                fixed4 _ShadowOffset;

                v2f SpriteVertShadow(appdata_t IN)
                {
                    v2f OUT;

                    UNITY_SETUP_INSTANCE_ID (IN);
                    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(OUT);

                    #ifdef UNITY_INSTANCING_ENABLED
                        IN.vertex.xy *= _Flip;
                    #endif

                    OUT.vertex = UnityObjectToClipPos(IN.vertex + _ShadowOffset);
                    OUT.texcoord = IN.texcoord;
                    OUT.color = IN.color * _Color * _RendererColor;

                    #ifdef PIXELSNAP_ON
                        OUT.vertex = UnityPixelSnap (OUT.vertex);
                    #endif

                    return OUT;
                }

                fixed4 SpriteFragShadow(v2f IN) : SV_Target
                {
                    fixed4 c = SampleSpriteTexture(IN.texcoord) * IN.color;
                    if (c.a < 0.99) discard;
                    c.rgb = _ShadowColor;
                    c.a = _ShadowColor.a;
                    return c;
                }

            ENDCG
            }

            Pass
            {
                CGPROGRAM
                #pragma vertex SpriteVert
                #pragma fragment SpriteFrag
                #pragma target 2.0
                #pragma multi_compile_instancing
                #pragma multi_compile _ PIXELSNAP_ON
                #pragma multi_compile _ ETC1_EXTERNAL_ALPHA
                #include "UnitySprites.cginc"
                ENDCG
            }
        }
    }