RoApp/Assets/Shaders/PostEffect/RadialBlurShader.shader

Shader "PostEffect/RadialBlurShader"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
		_IterationNumber("IterationNumber", Int) = 16
		_Intensity("Intensity", float) = 0.1
		_OffsetX("OffsetX", float) = 0.5
		_OffsetY("OffsetY", float) = 0.5
    }

	CGINCLUDE
	uniform sampler2D _MainTex;
	uniform float _Intensity;
	uniform float _OffsetX;
	uniform float _OffsetY;
	uniform int _IterationNumber;

	//uniform float _BlurFactor;	//模糊强度（0-0.05）
	//uniform float4 _BlurCenter; //模糊中心点xy值（0-1）屏幕空间
	#include "UnityCG.cginc"
	//#define SAMPLE_COUNT 16		//迭代次数

	fixed4 frag(v2f_img i) : SV_Target
	{
		////模糊方向为模糊中点指向边缘（当前像素点），而越边缘该值越大，越模糊
		//float2 dir = i.uv - _BlurCenter.xy;
		//float4 outColor = 0;
		////采样SAMPLE_COUNT次
		//for (int j = 0; j < SAMPLE_COUNT; ++j)
		//{
		//	//计算采样uv值：正常uv值+从中间向边缘逐渐增加的采样距离
		//	float2 uv = i.uv - _BlurFactor * dir * j;
		//	outColor += tex2D(_MainTex, uv);
		//}
		////取平均值
		//outColor /= SAMPLE_COUNT;
		//return outColor;
		float2 center = float2(_OffsetX, _OffsetY);
		float2 uv = i.uv;
		uv -= center;
		float4 color = float4(0.0, 0.0, 0.0, 0.0);
		_Intensity *= 0.085;
		float scale = 1;

		for (int j = 1; j < _IterationNumber; ++j)
		{
			color += tex2D(_MainTex, uv * scale + center);
			scale = 1 + (float(j * _Intensity));
		}

		color /= (float)_IterationNumber;

		return  color;
	}
	ENDCG

    SubShader
    {
		Pass
		{
			ZTest Always
			Cull Off
			ZWrite Off
			Fog{ Mode off }

			//调用CG函数	
			CGPROGRAM
			//使效率更高的编译宏
			#pragma fragmentoption ARB_precision_hint_fastest 
			//vert_img是在UnityCG.cginc中定义好的，当后处理vert阶段计算常规，可以直接使用自带的vert_img
			#pragma vertex vert_img
			#pragma fragment frag 
			ENDCG
		}
    }
	Fallback off
}