// threshold for mask can be controlled using vertex color alpha (useful for spriteRenderers or particle systems)
// _MainTex: alpha of this texture is used as a mask
// _EmissionTex: usually rgb noise texture, adjust it's scaling if needed
// color remap and oscilation for each channel of emission can be modified in _EmStrobeBFALR, _EmStrobeBFALG, _EmStrobeBFALB
// Base: base amplitude of brightness oscilation
// Freq: frequency of oscilation
// Ampl: amplitude of oscilation
// L: how much _EmissionTex affects this color

Shader "StandardWMask" {
	Properties {
		_Color ("Color", Color) = (1,1,1,1)
		[Header(Mask)]
		_MaskSoft ("Smoothness", Range (0.001, 1)) = .1
		[Space]

		_MaskBrightOffset ("Shadow Mask Offset", Range (-.5, .5)) = 0
		_MainTex ("Albedo (RGB)", 2D) = "white" {}
		_AlphaClip ("Alpha clip", Float) = 0.01
		_SpecGlossMap("Specular", 2D) = "white" {}

		_Specular ("Specular Mult", Range (0, 1)) = .5
		_Smoothness ("Glossiness Mult", Range (0, 1)) = .5

        [Normal][NoScaleOffset] _BumpMap ("Normal", 2D) = "bump" {}
		_BumpScale ("BumpScale", Range (0, 4)) = 1
		[Space(20)]
		_MaskEmissOffset ("Emis Mask Offset", Range (-.5, .5)) = 0
		[NoScaleOffset] _EmissionMap ("Emission Mask", 2D) = "white" {}
		[Space(20)]
		[Toggle] _QuantEmisPos ("Snap Emission?", Float) = 0
		[NoScaleOffset] _EmTxtrQuant ("Quantisize", Vector) = (1,1,0,0)
		[NoScaleOffset] _ColorPhase ("ColorPhase", Float) = 0

		[Space(20)]
		[Toggle] _UseColor ("Use Material Color?", Float) = 0
		[Toggle] _UseVertexColor ("Use Vertex?", Float) = 0
		[Space(20)]

		_EmSpeed ("UV Speed (XY) UV Scale (ZW)", Vector) = (0,5,1,1)
		_EmissionTex ("Emission FX", 2D) = "white" {}
	   	[HDR]_EmissionColor ("Emission Color", Color) = (1,1,1,1)

		[Header(Red remap)]
	   	[HDR]_EmisRemapR ("Remap", Color) = (1,1,1,1)
		_EmStrobeBFALR ("Oscilate [Base,Freq,Ampl,L]", Vector) = (.2,2,2,1)

		[Header(Green remap)]
	   	[HDR]_EmisRemapG ("Remap", Color) = (1,1,1,1)
		_EmStrobeBFALG ("Oscilate [Base,Freq,Ampl,L]", Vector) = (8,120,1.7,1)

		[Header(Blue remap)]
	   	[HDR]_EmisRemapB ("Remap", Color) = (1,1,1,1)
		_EmStrobeBFALB ("Oscilate [Base,Freq,Ampl,L]", Vector) = (2,.5,10,1)
	}

	SubShader {
		Tags { "Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent" }
		Blend SrcAlpha OneMinusSrcAlpha
		Cull off
		ZWrite Off

		CGPROGRAM
		#pragma surface surf StandardSpecular nofog keepalpha vertex:vert
		#pragma target 3.0
		#pragma multi_compile_instancing

		sampler2D _BumpMap;
		sampler2D _MainTex;
		sampler2D _SpecGlossMap;
		sampler2D _EmissionMap;
		sampler2D _EmissionTex;

		half _MaskSoft, _MaskEmissOffset, _MaskBrightOffset;
		half4 _EmissionTex_ST;
		half4 _EmissionColor;
		fixed4 _Color;
		half _AlphaClip;
		half _BumpScale, _ColorPhase;
		half _Smoothness;
		half _Specular;
		fixed _QuantEmisPos;

		float4 _EmSpeed;
		float4 _EmTxtrSize, _EmTxtrQuant;

		half4 _EmisRemapR, _EmisRemapG, _EmisRemapB;
		float4 _EmStrobeBFALR, _EmStrobeBFALG, _EmStrobeBFALB;

		struct Input {
			float2 uv_MainTex;
			float2 emisUV;
			float2 emisUVOffset;
			fixed4 color : COLOR;
			fixed3 strobe;
		};

		float quant(float q, float v){
			return floor(q/v)*v;
		}

		float2 quant(float2 q, float2 v){
			return floor(q/v)*v;
		}

		float TriangleWave( float x ) { return abs( frac(x+0.5)*2.0 - 1.0 ); }
		float SmoothCurve( float x ) { return x * x *( 3.0 - 2.0 * x ); }
		float SmoothTriangleWave( float x ) { return SmoothCurve( TriangleWave( x ) ); }


		void vert (inout appdata_full v, out Input o) {
			UNITY_INITIALIZE_OUTPUT(Input,o);

			o.emisUV = v.texcoord * _EmissionTex_ST.xy;

			o.emisUVOffset = _Time.xx * _EmSpeed.xy + _EmissionTex_ST.zw;
			o.emisUVOffset = lerp( o.emisUVOffset,  quant(o.emisUVOffset, 1/_EmTxtrQuant.xy), _QuantEmisPos);
			o.emisUVOffset = frac( o.emisUVOffset );

			o.strobe =
				fixed3(
					saturate( _EmStrobeBFALR.r + SmoothTriangleWave( ((_Time.x*(1+v.color.r))+_ColorPhase)*_EmStrobeBFALR.g) * _EmStrobeBFALR.b),
					saturate( _EmStrobeBFALG.r + SmoothTriangleWave( ((_Time.x*(1+v.color.g))+_ColorPhase)*_EmStrobeBFALG.g) * _EmStrobeBFALG.b),
					saturate( _EmStrobeBFALB.r + SmoothTriangleWave( ((_Time.x*(1+v.color.b))+_ColorPhase)*_EmStrobeBFALB.g) * _EmStrobeBFALB.b)
					);
		}

		void surf (Input IN, inout SurfaceOutputStandardSpecular o) {

			fixed4 c = tex2D (_MainTex, IN.uv_MainTex);

			half mm = IN.color.a+IN.color.a*_MaskSoft;
      // lowers brightness for 'burned effect'
			half bright = smoothstep(mm+_MaskBrightOffset, mm-_MaskSoft+_MaskBrightOffset, c.a);
			o.Albedo = c*bright;

			fixed4 tint = UNITY_ACCESS_INSTANCED_PROP(_Color_arr, _Color);
			o.Alpha = smoothstep(mm, mm-_MaskSoft,  c.a); // mask itself
			clip(c.a-_AlphaClip);

			fixed4 spec = tex2D(_SpecGlossMap, IN.uv_MainTex);
			o.Specular = spec.rgb * _Specular * bright;
			o.Smoothness = spec.a * _Smoothness * bright;

			o.Normal = UnpackScaleNormal(tex2D (_BumpMap, IN.uv_MainTex), _BumpScale);

			half3 e_clr = tex2D(_EmissionMap, IN.uv_MainTex);
			half3 e_ovr = tex2D(_EmissionTex, IN.emisUV + IN.emisUVOffset).rgb;

			e_clr = IN.color.rgb * e_clr;

			half3 osc =
				_EmisRemapR * saturate(lerp(e_clr.r, e_ovr.r*e_clr.r, _EmStrobeBFALR.a)) * IN.strobe.r +
				_EmisRemapG * saturate(lerp(e_clr.g, e_ovr.g*e_clr.g, _EmStrobeBFALG.a)) * IN.strobe.g +
				_EmisRemapB * saturate(lerp(e_clr.b, e_ovr.b*e_clr.b, _EmStrobeBFALB.a)) * IN.strobe.b;

			tint.rgb = osc*tint.rgb;

			o.Emission = tint.rgb * _EmissionColor * TriangleWave( smoothstep(mm+_MaskEmissOffset, mm-_MaskSoft+_MaskEmissOffset, c.a) );
		}
		ENDCG
	}
	FallBack "Diffuse"
}