[游戏开发]unity ui 扫光shader

_LightTex 1：扫光贴图
_Color 2：扫光颜色
_Intensity 3：强度
_Speed 4：运动速度
_Angle 5：扫光贴图uv中心点旋转

Shader "Unlit/UIWalklight"
{
	Properties
	{
		_MainTex ("Base (RGB), Alpha (A)", 2D) = "black" {}
		_LightTex ("Light", 2D) = "black" {}
		_Color ("Color", Color) = (255,255,255,1)
		_Intensity("Intensity", Float) = 1
		_Speed("Speed", Float) = 1
		_Angle("Angle", Float) = 0
		
	}
	
	SubShader
	{
		LOD 100
		Tags
		{
			"Queue" = "Transparent"
			"IgnoreProjector" = "True"
			"RenderType" = "Transparent"
		}
		Pass
		{
			Cull Off
			Lighting Off
			ZWrite Off
			Fog { Mode Off }
			Offset -1, -1
			Blend SrcAlpha OneMinusSrcAlpha

			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag

			#include "UnityCG.cginc"

			sampler2D _MainTex;
			float4 _MainTex_ST;
			sampler2D _LightTex;
			float4 _LightTex_ST;
			float4 _Color;
			float _Speed,_Angle,_Intensity;
			struct appdata_t
			{
				float4 vertex : POSITION;
				float2 texcoord : TEXCOORD0;
				//float2 texcoord1 : TEXCOORD1;
				fixed4 color : COLOR;
			};
	
			struct v2f
			{
				float4 vertex : SV_POSITION;
				float2 texcoord : TEXCOORD0;
				//float2 texcoord1 : TEXCOORD1;
				fixed4 color : COLOR;
				//half2 posInPanel : TEXCOORD3;
			};
	
			v2f o;

			v2f vert (appdata_t v)
			{
				o.vertex = UnityObjectToClipPos(v.vertex);
				//float2 clipSpace = o.vertex.xy / o.vertex.w;  
			    //o.posInPanel = (clipSpace.xy + 1) * 0.5 - _PanelRect.xy;// Fix to 0-1//
				o.texcoord = TRANSFORM_TEX(v.texcoord,_MainTex);
				//o.texcoord1 = v.texcoord1;
				o.color = v.color;
				return o;
			}
				
			fixed4 frag (v2f IN) : COLOR
			{
				fixed4 main = tex2D(_MainTex, IN.texcoord);
				float2 newUV = IN.texcoord.xy-float2(0.5,0.5);
			    newUV =  float2(newUV.x*cos(_Angle)-newUV.y*sin(_Angle),newUV.y*cos(_Angle) + newUV.x*sin(_Angle));
				newUV += float2(0.5,0.5);
                half lightU = newUV.x - frac(_Time.y*_Speed);
                half2 lightUV = half2(lightU, newUV.y) * _LightTex_ST.xy + _LightTex_ST.zw;
                fixed4 light = tex2D(_LightTex, lightUV)*_Intensity;
				fixed4 col = main + main * light.r*_Color;
				return  col * IN.color;

				return col;
			}
			ENDCG
		}
	}

	SubShader
	{
		LOD 100

		Tags
		{
			"Queue" = "Transparent"
			"IgnoreProjector" = "True"
			"RenderType" = "Transparent"
		}
		
		Pass
		{
			Cull Off
			Lighting Off
			ZWrite Off
			Fog { Mode Off }
			Offset -1, -1
			ColorMask RGB
			Blend SrcAlpha OneMinusSrcAlpha
			ColorMaterial AmbientAndDiffuse
			
			SetTexture [_MainTex]
			{
				Combine Texture * Primary
			}
		}
	}
}