Shader "MY/Particles/AlphaBlendedGlow"
{
	Properties
	{
		_TintColor("Tint Color", Color) = (0.5,0.5,0.5,0.5)
		_MainTex("Particle Texture", 2D) = "white" {}
		_AtmoColor("Atmosphere Color", Color) = (0, 0.4, 1.0, 1)
		_Size("Size", Float) = 0.1
		_OutLightPow("Falloff",Float) = 5
		_OutLightStrength("Transparency", Float) = 15
		_Value("Value", float) = 2.0
	}

		Category
		{
			Tags { "Queue" = "Transparent" "IgnoreProjector" = "True"}
			ColorMask RGB
			Blend SrcAlpha OneMinusSrcAlpha
			Cull Off
			Lighting Off
			ZWrite Off

			SubShader
			{
				Pass
				{
					CGPROGRAM

					#pragma vertex vert
					#pragma fragment frag
					#pragma multi_compile_fog
					#include "UnityCG.cginc"

					sampler2D _MainTex;
					half4 _MainTex_ST;
					fixed4 _TintColor;
					half _Value;

					struct appdata_t
					{
						half4 vertex : POSITION;
						fixed4 color : COLOR;
						half2 texcoord : TEXCOORD0;
						UNITY_VERTEX_INPUT_INSTANCE_ID
					};

					struct v2f
					{
						half4 vertex : POSITION;
						fixed4 color : COLOR;
						half2 texcoord : TEXCOORD0;
						UNITY_FOG_COORDS(1)
						UNITY_VERTEX_OUTPUT_STEREO
					};

					v2f vert(appdata_t v)
					{
						v2f o;
						UNITY_SETUP_INSTANCE_ID(v);
						UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
						o.vertex = UnityObjectToClipPos(v.vertex);
						o.color = v.color;
						o.texcoord = TRANSFORM_TEX(v.texcoord,_MainTex);
						UNITY_TRANSFER_FOG(o,o.vertex);
						return o;
					}

					fixed4 frag(v2f i) : COLOR
					{
						fixed4 col = _Value * i.color * _TintColor * tex2D(_MainTex, i.texcoord);
						UNITY_APPLY_FOG(i.fogCoord, col);
						return col;
					}

					ENDCG
				}

				Pass
				{
					Name "AtmosphereBase"
					Tags{ "LightMode" = "Always" }
					Cull Front
					Blend SrcAlpha One

					CGPROGRAM
					#pragma vertex vert
					#pragma fragment frag
					#include "UnityCG.cginc"
					uniform fixed4 _Color;
					uniform fixed4 _AtmoColor;
					uniform half _Size;
					uniform half _OutLightPow;
					uniform half _OutLightStrength;

					struct vertexOutput
					{
						half4 pos:SV_POSITION;
						half3 normal:TEXCOORD0;
						half3 worldvertpos:TEXCOORD1;
					};

					vertexOutput vert(appdata_base v)
					{
						vertexOutput o;
						v.vertex.xyz += v.normal*_Size;
						o.pos = UnityObjectToClipPos(v.vertex);
						o.normal = v.normal;
						o.worldvertpos = mul(unity_ObjectToWorld, v.vertex);
						return o;
					}

					fixed4 frag(vertexOutput i) :COLOR
					{
						i.normal = normalize(i.normal);
						half3 viewdir = normalize(i.worldvertpos.xyz - _WorldSpaceCameraPos.xyz);
						fixed4 color = _AtmoColor;
						color.a = pow(saturate(dot(viewdir, i.normal)), _OutLightPow);
						color.a *= _OutLightStrength * dot(viewdir, i.normal);
						return color;
					}
					ENDCG
				}
			}
		}
}