Shader "Custom/ColorChanger" {
	Properties {
		[PerRendererData]_Color ("Color", Color) = (1,1,1,1)
		[PerRendererData]_MainTex ("Albedo (RGB)", 2D) = "white" {}
		_Grayscale ("Grayscale", Range (0, 1)) = 0.0
		_Glossiness ("Smoothness", Range(0,1)) = 0.5
		_Metallic ("Metallic", Range(0,1)) = 0.0
	}
	SubShader {
		Tags { "RenderType"="Opaque" }
		Blend SrcAlpha OneMinusSrcAlpha
		Cull Back
		LOD 200

		CGPROGRAM

		#pragma surface surf Standard fullforwardshadows
		#pragma target 3.0


		sampler2D _MainTex;
		uniform float _Grayscale;

		struct Input {
			float2 uv_MainTex;
			float4 color : COLOR;
		};

		void vert (inout appdata_full v, out Input o){
			UNITY_INITIALIZE_OUTPUT(Input,o);
			o.color = v.color;
		}

		half _Glossiness;
		half _Metallic;
		fixed4 _Color;

		// Add instancing support for this shader. You need to check 'Enable Instancing' on materials that use the shader.
		// See https://docs.unity3d.com/Manual/GPUInstancing.html for more information about instancing.
		// #pragma instancing_options assumeuniformscaling
		UNITY_INSTANCING_BUFFER_START(Props)
			// put more per-instance properties here
		UNITY_INSTANCING_BUFFER_END(Props)

		void surf (Input IN, inout SurfaceOutputStandard o) {
			// Albedo comes from a texture tinted by color
			fixed4 c = tex2D (_MainTex, IN.uv_MainTex) * _Color;
			o.Albedo = lerp(c.rgb * IN.color.rgb, dot(c.rgb * IN.color.rgb, float3(0.3, 0.59, 0.11)), _Grayscale);
			// Metallic and smoothness come from slider variables
			o.Metallic = _Metallic;
			o.Smoothness = _Glossiness;
			float alpha = c.a * IN.color.a;
			o.Alpha = alpha;
		}
		ENDCG
	}
	FallBack "Diffuse"
}
