Shader "GPUInstancer/Nature/Tree Soft Occlusion Bark" {
    Properties{
        _Color("Main Color", Color) = (1,1,1,0)
        _MainTex("Main Texture", 2D) = "white" {}
        _BaseLight("Base Light", Range(0, 1)) = 0.35
        _AO("Amb. Occlusion", Range(0, 10)) = 2.4
    }

        SubShader{
            Tags {
                "IgnoreProjector" = "True"
                "RenderType" = "TreeOpaque"
                "DisableBatching" = "True"
            }

            Pass {
                Lighting On

                CGPROGRAM
                #include "UnityCG.cginc"
                #include "../../Include/GPUInstancerInclude.cginc"
                #pragma vertex bark_gpui
                #pragma fragment frag
                #pragma multi_compile_fog
                #pragma multi_compile _ LOD_FADE_CROSSFADE
                #pragma multi_compile_instancing
                #pragma instancing_options procedural:setupGPUI
                #include "UnityBuiltin2xTreeLibrary.cginc"

                sampler2D _MainTex;

                struct v2f_gpui {
                    float4 pos : SV_POSITION;
                    float4 uv : TEXCOORD0;
                    half4 color : TEXCOORD1;
                    uint gpuiInstanceID : SV_InstanceID;
                    UNITY_FOG_COORDS(2)
                    UNITY_VERTEX_OUTPUT_STEREO
                };

                v2f_gpui bark_gpui(appdata_tree v)
                {
                    v2f_gpui o;
                    UNITY_SETUP_INSTANCE_ID(v);
                    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
    #ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
                    o.gpuiInstanceID = gpui_InstanceID;
    #else
                    o.gpuiInstanceID = 0;
    #endif
                    //TerrainAnimateTree(v.vertex, v.color.w);

                    float3 viewpos = UnityObjectToViewPos(v.vertex);
                    o.pos = UnityObjectToClipPos(v.vertex);
                    o.uv = v.texcoord;

                    float4 lightDir = 0;
                    float4 lightColor = 0;
                    lightDir.w = _AO;

                    float4 light = UNITY_LIGHTMODEL_AMBIENT;
                    for (int i = 0; i < 4; i++) {
                        float atten = 1.0;

                        float3 toLight = unity_LightPosition[i].xyz - viewpos.xyz * unity_LightPosition[i].w;
                        toLight.z *= -1.0;
                        lightDir.xyz = mul((float3x3)unity_CameraToWorld, normalize(toLight));
                        float lengthSq = dot(toLight, toLight);
                        atten = 1.0 / (1.0 + lengthSq * unity_LightAtten[i].z);

                        lightColor.rgb = unity_LightColor[i].rgb;

                        float diffuse = dot(v.normal, lightDir.xyz);
                        diffuse = max(0, diffuse);
                        diffuse *= _AO * v.tangent.w + _BaseLight;
                        light += lightColor * (diffuse * atten);
                    }

                    light.a = 1;
                    float4 col = frac((unity_ObjectToWorld._m03_m13_m23.x + unity_ObjectToWorld._m03_m13_m23.z)) * 0.4 + 0.6;
                    col.a = 1;
                    o.color = light * _Color * col;


                    UNITY_TRANSFER_FOG(o,o.pos);
                    return o;
                }

                fixed4 frag(v2f_gpui input) : SV_Target
                {
    #ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
                    gpui_InstanceID = input.gpuiInstanceID;
    #endif
                    UNITY_APPLY_DITHER_CROSSFADE(input.pos.xy);
                    fixed4 col = input.color;
                    col.rgb *= tex2D(_MainTex, input.uv.xy).rgb;
                    UNITY_APPLY_FOG(input.fogCoord, col);
                    UNITY_OPAQUE_ALPHA(col.a);
                    return col;
                }
                ENDCG
            }

            Pass {
                Name "ShadowCaster"
                Tags { "LightMode" = "ShadowCaster" }

                CGPROGRAM
                #pragma vertex vert
                #pragma fragment frag
                #pragma multi_compile_shadowcaster
                #pragma multi_compile_instancing
                #pragma instancing_options procedural:setupGPUI
                #include "UnityCG.cginc"
                #include "../../Include/GPUInstancerInclude.cginc"
                #include "TerrainEngine.cginc"

                struct v2f {
                    V2F_SHADOW_CASTER;
                    UNITY_VERTEX_OUTPUT_STEREO
                };

                struct appdata {
                    float4 vertex : POSITION;
                    float3 normal : NORMAL;
                    fixed4 color : COLOR;
                    UNITY_VERTEX_INPUT_INSTANCE_ID
                };

                v2f vert(appdata v)
                {
                    v2f o;
                    UNITY_SETUP_INSTANCE_ID(v);
                    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
                    //TerrainAnimateTree(v.vertex, v.color.w);
                    TRANSFER_SHADOW_CASTER_NORMALOFFSET(o)
                    return o;
                }

                float4 frag(v2f i) : SV_Target
                {
                    SHADOW_CASTER_FRAGMENT(i)
                }
                ENDCG
            }
        }
}