[unity shader amplify shader editor (ASE) Chapter 9]

1. To continue Chapter eight ASE effect

Streamer Shader Complete code blocks and node connections are at the top ！

To facilitate observation , Here you are Chapter eight ASE Full node connection of the effect .
What is shown below is ASE The effect of the eighth part is a complete code block .

Shader "Samples/Light Flow"
{
    
	Properties
	{
    
		// Keyword enumeration ,0 position X Direction ,1 by Y Direction .
		[KeywordEnum(x,y)] _Flow_Diretion("Flow_Diretion", Float) = 0
		_FlowSpeed("Flow Speed", Float) = 1
		
		_Tex("Tex", 2D) = "white" {
    }
		_Color("Color", Color) = (0,1,1,1)

	}

	SubShader
	{
    
		Tags {
     "RenderType"="Transparent" "Queue"="Transparent" }

		Blend One One
		Cull Off
		
		Pass
		{
    
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag

			#include "UnityCG.cginc"
			//————————————————————————————————————————————————————————————————————
			// Define enumeration keywords 
			#pragma shader_feature_local _FLOW_DIRETION_X _FLOW_DIRETION_Y
			//————————————————————————————————————————————————————————————————————
			struct v2f
			{
    
				float4 vertex : SV_POSITION;
				float2 texcoord : TEXCOORD0;
			};

			sampler2D _Tex;
			float _FlowSpeed;
			float4 _Color;
			float4 _Tex_ST;

			
			v2f vert (appdata_base v)
			{
    
				v2f o;
				
				o.texcoord = TRANSFORM_TEX(v.texcoord,_Tex);
				o.vertex = UnityObjectToClipPos(v.vertex);
				
				return o;
			}
			
			fixed4 frag (v2f i) : SV_Target
			{
    
				float2 texcoord;

				//————————————————————————————————————————————————————————————————————
				// Judge the flow direction 
				#if _DIRECTION_X
				texcoord = float2(i.texcoord.x + _Time.x * _Speed,
								i.texcoord.y);
				#elif _DIRECTION_Y
				texcoord = float2(i.texcoord.x,
								i.texcoord.y + _Time.x * _Speed,);
				#endif
				//————————————————————————————————————————————————————————————————————

				return tex2D(_Tex,texcoord) * _Color;
			}
			ENDCG
		}
	}
}

2.Shader Code block explanation

2.1.Properties Code block

• About Properties The code rules can be seen in the previous Properties Introduce , What I don't understand Leave a comment .

Shader "Samples/Light Flow"
{
    
	Properties
	{
    
		// Keyword enumeration ,0 position X Direction ,1 by Y Direction .
		[KeywordEnum(x,y)] _Flow_Diretion("Flow_Diretion", Float) = 0
		_FlowSpeed("Flow Speed", Float) = 1
		
		_Tex("Tex", 2D) = "white" {
    }
		_Color("Color", Color) = (0,1,1,1)

	}

1. Open the mapping attribute of streamer effect _Tex And color attributes _Color
2. For the convenience of selecting the flow direction of the beam , Attribute is required _DIRECTION Before adding [KeywordEnum(x,y)] Keyword enumeration instruction , In this way, you can select from the material panel through the following options .
   That is to say ：[KeywordEnum(x,y)] _Flow_Diretion("Flow_Diretion", Float) = 0
3. add to _Speed It is used to adjust the flow speed of the light beam .

2.2.SubShader Code block

• because Shader Effect needs to be used Blending function , So you need to SubShader Set both the render type and the render queue to “Transparent”. Then set the blending mode to “Blend one one”, And turn off geometry culling . The code block is as follows ：

	SubShader
	{
    
		Tags {
     "RenderType"="Transparent" "Queue"="Transparent" }

		Blend One One
		Cull Off

2.3.Pass Compile instruction code block

• In the compile instruction , add to shader_feature The instruction defines the direction of flow X and Y The enumeration keywords of are
  _FLOW_DIRETION_X and _FLOW_DIRETION_Y. as follows ：

		Pass
		{
    
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag

			#include "UnityCG.cginc"
			//————————————————————————————————————————————————————————————————————
			// Define enumeration keywords 
			#pragma shader_feature_local _FLOW_DIRETION_X _FLOW_DIRETION_Y
			//————————————————————————————————————————————————————————————————————

besides , You can also use “multi_compile” Instructions . About customizing material panel content , You need to make a separate article . Portal ------------------------------------------------

2.4. Declare attribute variables 、 Get data code block

• Relatively easy , The previous chapter has a detailed introduction , for example Pass Third articles .

			struct v2f
			{
    
				float4 vertex : SV_POSITION;
				float2 texcoord : TEXCOORD0;
			};
			sampler2D _Tex;
			float _FlowSpeed;
			float4 _Color;
			float4 _Tex_ST;

2.5. Vertex shader code block

• It is introduced in the comments of the code block .

			v2f vert (appdata_base v)
			{
    
				v2f o;
				// use TRANSFORM_TEX() The macro calculates the texture coordinates of the beam .
				o.texcoord = TRANSFORM_TEX(v.texcoord,_Tex);
				// Use UnityObjectToClipPos() Function to get the coordinates of cutting space vertices , Then pass it to the clip shader .
				o.vertex = UnityObjectToClipPos(v.vertex);
				
				return o;
			}

2.6. Fragment shader code block

• In the fragment shader , Judge by enumerating keywords ：
• When the flow direction is X when , The time variable is added to the texture coordinates X On weight ;
• When the flow direction is Y when , The time variable is added to the texture coordinates Y On weight .
• Then the beam texture is sampled using the calculated texture coordinates ,
• Finally multiply by the color attribute , Return to the clip shader .

			fixed4 frag (v2f i) : SV_Target
			{
    
				float2 texcoord;

				//————————————————————————————————————————————————————————————————————
				// Judge the flow direction 
				#if _DIRECTION_X
				texcoord = float2(i.texcoord.x + _Time.x * _Speed,
								i.texcoord.y);
				#elif _DIRECTION_Y
				texcoord = float2(i.texcoord.x,
								i.texcoord.y + _Time.x * _Speed,);
				#endif
				//————————————————————————————————————————————————————————————————————

				return tex2D(_Tex,texcoord) * _Color;
			}
			ENDCG
		}
	}
}