Shader error Unity 2019.2.1f1

Hi, I'm having several issues compiling with this Shader error. Please help fix. I tried to replace the sampler2D_float _CameraDepthTexture; with UNITY_DECLARE_DEPTH_TEXTURE(_CameraDepthTexture); but it's not working for this file.

  /**
  \author Michael Mara and Morgan McGuire, Casual Effects. 2015.
  */
  Shader "Hidden/Post FX/Screen Space Reflection"
  {
      Properties
      {
          _MainTex ("Base (RGB)", 2D) = "white" {}
      }
  
      CGINCLUDE
  
          #pragma target 3.0
          #include "UnityCG.cginc"
          #include "UnityPBSLighting.cginc"
          #include "UnityStandardBRDF.cginc"
          #include "UnityStandardUtils.cginc"
          #include "Common.cginc"
          #include "ScreenSpaceRaytrace.cginc"
  
          float4   _ProjInfo;
          float4x4 _WorldToCameraMatrix;
          float4x4 _CameraToWorldMatrix;
          float4x4 _ProjectToPixelMatrix;
          float2   _ScreenSize;
          float2   _ReflectionBufferSize;
          float2   _InvScreenSize;
          float3   _CameraClipInfo;
  
          sampler2D _CameraGBufferTexture0;
          sampler2D _CameraGBufferTexture1;
          sampler2D _CameraGBufferTexture2;
          sampler2D _CameraGBufferTexture3;
          sampler2D _CameraReflectionsTexture;
  
          float _CurrentMipLevel;
          float _RayStepSize;
          float _MaxRayTraceDistance;
          float _LayerThickness;
          float _FresnelFade;
          float _FresnelFadePower;
          float _ReflectionBlur;
  
  
          int _HalfResolution;
          int _TreatBackfaceHitAsMiss;
          int _AllowBackwardsRays;
  
  
          // RG: SS Hitpoint of ray
          // B: distance ray travelled, used for mip-selection in the final resolve
          // A: confidence value
          sampler2D _HitPointTexture;
          sampler2D _FinalReflectionTexture;
  
          // RGB: camera-space normal (encoded in [0-1])
          // A: Roughness
          sampler2D _NormalAndRoughnessTexture;
  
          int _EnableRefine;
          int _AdditiveReflection;
  
          float _ScreenEdgeFading;
  
          int _MaxSteps;
  
          int _BilateralUpsampling;
  
          float _MaxRoughness;
          float _RoughnessFalloffRange;
          float _SSRMultiplier;
  
          float _FadeDistance;
  
          int _TraceBehindObjects;
          int _UseEdgeDetector;
          int _HighlightSuppression;
  
          /** The height in pixels of a 1m object if viewed from 1m away. */
          float _PixelsPerMeterAtOneMeter;
  
          // For temporal filtering:
          float4x4    _CurrentCameraToPreviousCamera;
          sampler2D   _PreviousReflectionTexture;
          sampler2D   _PreviousCSZBuffer;
          float       _TemporalAlpha;
          int         _UseTemporalConfidence;
  
          struct v2f
          {
              float4 pos : SV_POSITION;
              float2 uv : TEXCOORD0;
              float2 uv2 : TEXCOORD1;
          };
  
          v2f vert( appdata_img v )
          {
              v2f o;
  
              o.pos = UnityObjectToClipPos(v.vertex);
              o.uv = v.texcoord.xy;
              o.uv2 = v.texcoord.xy;
  
          #if UNITY_UV_STARTS_AT_TOP
              if (_MainTex_TexelSize.y < 0)
                  o.uv2.y = 1.0 - o.uv2.y;
          #endif
  
              return o;
          }
  
          float2 mipToSize(int mip)
          {
              return floor(_ReflectionBufferSize * exp2(-mip));
          }
  
          float3 ReconstructCSPosition(float2 S, float z)
          {
              float linEyeZ = -LinearEyeDepth(z);
              return float3((((S.xy * _MainTex_TexelSize.zw)) * _ProjInfo.xy + _ProjInfo.zw) * linEyeZ, linEyeZ);
          }
  
          /** Read the camera-space position of the point at screen-space pixel ssP */
          float3 GetPosition(float2 ssP)
          {
              float3 P;
  
              P.z = SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture, ssP.xy);
  
              // Offset to pixel center
              P = ReconstructCSPosition(float2(ssP) /*+ float2(0.5, 0.5)*/, P.z);
              return P;
          }
  
          float applyEdgeFade(float2 tsP, float fadeStrength)
          {
              float maxFade = 0.1;
  
              float2 itsP = float2(1.0, 1.0) - tsP;
              float dist = min(min(itsP.x, itsP.y), min(tsP.x, tsP.x));
              float fade = dist / (maxFade*fadeStrength + 0.001);
              fade = max(min(fade, 1.0), 0.0);
              fade = pow(fade, 0.2);
  
              return fade;
          }
  
          float3 csMirrorVector(float3 csPosition, float3 csN)
          {
              float3 csE = -normalize(csPosition.xyz);
              float cos_o = dot(csN, csE);
              float3 c_mi = normalize((csN * (2.0 * cos_o)) - csE);
  
              return c_mi;
          }
  
          float4 fragRaytrace(v2f i, int stepRate)
          {
              float2 ssP = i.uv2.xy;
              float3 csPosition = GetPosition(ssP);
  
              float smoothness = tex2D(_CameraGBufferTexture1, ssP).a;
              if (csPosition.z < -100.0 || smoothness == 0.0)
              {
                  return float4(0.0,0.0,0.0,0.0);
              }
  
              float3 wsNormal = tex2D(_CameraGBufferTexture2, ssP).rgb * 2.0 - 1.0;
  
              int2 ssC = int2(ssP * _ScreenSize);
  
              float3 csN = mul((float3x3)(_WorldToCameraMatrix), wsNormal);
              float3 csRayDirection = csMirrorVector(csPosition, csN);
  
              if (_AllowBackwardsRays == 0 && csRayDirection.z > 0.0)
              {
                  return float4(0.0, 0.0, 0.0, 0.0);
              }
  
              float maxRayTraceDistance = _MaxRayTraceDistance;
              float jitterFraction = 0.0f;
              float layerThickness = _LayerThickness;
  
              int maxSteps = _MaxSteps;
  
              // Bump the ray more in world space as it gets farther away (and so each pixel covers more WS distance)
              float rayBump = max(-0.01*csPosition.z, 0.001);
              float2 hitPixel;
              float3 csHitPoint;
              float stepCount;
  
              bool wasHit = castDenseScreenSpaceRay
                          (csPosition + (csN) * rayBump,
                          csRayDirection,
                          _ProjectToPixelMatrix,
                          _ScreenSize,
                          _CameraClipInfo,
                          jitterFraction,
                          maxSteps,
                          layerThickness,
                          maxRayTraceDistance,
                          hitPixel,
                          stepRate,
                          _TraceBehindObjects == 1,
                          csHitPoint,
                          stepCount);
  
              float2 tsPResult = hitPixel / _ScreenSize;
  
              float rayDist = dot(csHitPoint - csPosition, csRayDirection);
              float confidence = 0.0;
  
              if (wasHit)
              {
                  confidence = Pow2(1.0 - max(2.0*float(stepCount) / float(maxSteps) - 1.0, 0.0));
                  confidence *= clamp(((_MaxRayTraceDistance - rayDist) / _FadeDistance), 0.0, 1.0);
  
                  // Fake fresnel fade
                  float3 csE = -normalize(csPosition.xyz);
                  confidence *= max(0.0, lerp(pow(abs(dot(csRayDirection, -csE)), _FresnelFadePower), 1, 1.0 - _FresnelFade));
  
                  if (_TreatBackfaceHitAsMiss > 0)
                  {
                      float3 wsHitNormal = tex2Dlod(_CameraGBufferTexture2, float4(tsPResult, 0, 0)).rgb * 2.0 - 1.0;
                      float3 wsRayDirection = mul(_CameraToWorldMatrix, float4(csRayDirection, 0)).xyz;
  
                      if (dot(wsHitNormal, wsRayDirection) > 0)
                      {
                          confidence = 0.0;
                      }
                  }
              }
  
              // Fade out reflections that hit near edge of screen, to prevent abrupt appearance/disappearance when object go off screen
              // Fade out reflections that hit near edge of screen,
              // to prevent abrupt appearance/disappearance when object go off screen
              float vignette = applyEdgeFade(tsPResult, _ScreenEdgeFading);
              confidence *= vignette;
              confidence *= vignette;
  
              return float4(tsPResult, rayDist, confidence);
          }
  
          float4 fragComposite(v2f i) : SV_Target
          {
              // Pixel being shaded
              float2 tsP = i.uv2.xy;
  
              // View space point being shaded
              float3 C = GetPosition(tsP);
  
              // Final image before this pass
              float4 gbuffer3 = tex2D(_MainTex, i.uv);
  
              float4 specEmission = float4(0.0,0.0,0.0,0.0);
              float3 specColor = tex2D(_CameraGBufferTexture1, tsP).rgb;
  
              float roughness = tex2D(_CameraGBufferTexture1, tsP).a;
  
              float4 reflectionTexel = tex2D(_FinalReflectionTexture, tsP);
  
              float4 gbuffer0 = tex2D(_CameraGBufferTexture0, tsP);
              // Let core Unity functions do the dirty work of applying the BRDF
              float3 baseColor = gbuffer0.rgb;
              float occlusion = gbuffer0.a;
              float oneMinusReflectivity;
              baseColor = EnergyConservationBetweenDiffuseAndSpecular(baseColor, specColor, oneMinusReflectivity);
  
              float3 wsNormal = tex2D(_CameraGBufferTexture2, tsP).rgb * 2.0 - 1.0;
  
              float3 csEyeVec = normalize(C);
              float3 eyeVec = mul(_CameraToWorldMatrix, float4(csEyeVec, 0)).xyz;
  
              float3 worldPos =  mul(_CameraToWorldMatrix, float4(C, 1)).xyz;
  
              float cos_o = dot(wsNormal, eyeVec);
              float3 w_mi = -normalize((wsNormal * (2.0 * cos_o)) - eyeVec);
  
              float3 incomingRadiance = reflectionTexel.rgb;
  
              UnityLight light;
              light.color = 0;
              light.dir = 0;
              #if UNITY_VERSION < 550
                  light.ndotl = 0;
              #endif
  
              UnityIndirect ind;
              ind.diffuse = 0;
              ind.specular = incomingRadiance;
  
              float3 ssrResult = UNITY_BRDF_PBS (0, specColor, oneMinusReflectivity, roughness, wsNormal, -eyeVec, light, ind).rgb * _SSRMultiplier;
              float confidence = reflectionTexel.a;
  
              specEmission.rgb = tex2D(_CameraReflectionsTexture, tsP).rgb;
              float3 finalGlossyTerm;
  
              // Subtract out Unity's glossy result: (we're just applying the delta)
              if (_AdditiveReflection == 0)
              {
                  gbuffer3 -= specEmission;
                  // We may have blown out our dynamic range by adding then subtracting the reflection probes.
                  // As a half-measure to fix this, simply clamp to zero
                  gbuffer3 = max(gbuffer3, 0);
                  finalGlossyTerm = lerp(specEmission.rgb, ssrResult, saturate(confidence));
              }
              else
              {
                  finalGlossyTerm = ssrResult*saturate(confidence);
              }
  
              finalGlossyTerm *= occlusion;
  
              // Additively blend the glossy GI result with the output buffer
              return gbuffer3 + float4(finalGlossyTerm, 0);
          }
  
          float roughnessWeight(float midpointRoughness, float tapRoughness)
          {
              return (1.0 - sqrt(sqrt(abs(midpointRoughness-tapRoughness))));
          }
  
          float normalWeight(float3 midpointNormal, float3 tapNormal)
          {
              return clamp(dot(midpointNormal, tapNormal), 0, 1);
          }
  
          float highlightDecompression(float x)
          {
              return x / (1.0 - x);
          }
  
          float3 highlightDecompression(float3 x)
          {
              return float3(
                  highlightDecompression(x.x),
                  highlightDecompression(x.y),
                  highlightDecompression(x.z)
              );
          }
  
          float highlightCompression(float x)
          {
              return x / (1.0 + x);
          }
  
          float3 highlightCompression(float3 x)
          {
              return float3(
                  highlightCompression(x.x),
                  highlightCompression(x.y),
                  highlightCompression(x.z)
              );
          }
  
          float4 _Axis;
          float4 fragGBlur(v2f i) : SV_Target
          {
              int radius = 4;
  
              // Pixel being shaded
              float2 tsP = i.uv2.xy;
  
              float weightSum = 0.0;
              float gaussWeights[5] = { 0.225, 0.150, 0.110, 0.075, 0.0525 };//{0.225, 0.150, 0.110, 0.075, 0.0525};
              float4 resultSum = float4(0.0, 0.0, 0.0, 0.0);
              float4 unweightedResultSum = float4(0.0, 0.0, 0.0, 0.0);
              float4 nAndRough = tex2D(_NormalAndRoughnessTexture, tsP);
              float midpointRoughness = nAndRough.a;
              float3 midpointNormal = nAndRough.rgb * 2 - 1;
  
              for (int i = -radius; i <= radius; ++i)
              {
                  float4 temp;
                  float tapRoughness;
                  float3 tapNormal;
                  float2 tsTap = tsP + (_Axis.xy * _MainTex_TexelSize.xy * float2(i,i)*2.0);
  
                  temp = tex2D(_MainTex, tsTap);
  
                  float weight = temp.a * gaussWeights[abs(i)];
                  // Bilateral filtering
                  // if (_ImproveCorners)
                  // {
                      nAndRough = tex2D(_NormalAndRoughnessTexture, tsTap);
                      tapRoughness = nAndRough.a;
                      tapNormal = nAndRough.rgb * 2 - 1;
                      weight *= normalWeight(midpointNormal, tapNormal);
                  // }
  
                  weightSum += weight;
  
                  if (_HighlightSuppression)
                  {
                      temp.rgb = highlightCompression(temp.rgb);
                  }
  
                  unweightedResultSum += temp;
                  resultSum += temp*weight;
              }
  
              if (weightSum > 0.01)
              {
                  float invWeightSum = (1.0/weightSum);
                  // Adding the sqrt seems to decrease temporal flickering at the expense
                  // of having larger "halos" of fallback on rough surfaces
                  // Subject to change with testing. Sqrt around only half the expression is *intentional*.
                  float confidence = min(resultSum.a * sqrt(max(invWeightSum, 2.0)), 1.0);
                  float3 finalColor = resultSum.rgb * invWeightSum;
  
                  if (_HighlightSuppression)
                  {
                      finalColor = highlightDecompression(finalColor);
                  }
  
                  return float4(finalColor, confidence);
              }
              else
              {
                  float3 finalColor = unweightedResultSum.rgb / (2 * radius + 1);
  
                  if (_HighlightSuppression)
                  {
                      finalColor = highlightDecompression(finalColor);
                  }
  
                  return float4(finalColor, 0.0);
              }
          }
  
          sampler2D _ReflectionTexture0;
          sampler2D _ReflectionTexture1;
          sampler2D _ReflectionTexture2;
          sampler2D _ReflectionTexture3;
          sampler2D _ReflectionTexture4;
  
          // Simulate mip maps, since we don't have NPOT mip-chains
          float4 getReflectionValue(float2 tsP, int mip)
          {
              float4 coord = float4(tsP,0,0);
              if (mip == 0)
              {
                  return tex2Dlod(_ReflectionTexture0, coord);
              }
              else if (mip == 1)
              {
                  return tex2Dlod(_ReflectionTexture1, coord);
              }
              else if (mip == 2)
              {
                  return tex2Dlod(_ReflectionTexture2, coord);
              }
              else if (mip == 3)
              {
                  return tex2Dlod(_ReflectionTexture3, coord);
              }
              else
              {
                  return tex2Dlod(_ReflectionTexture4, coord);
              }
          }
  
          sampler2D _EdgeTexture0;
          sampler2D _EdgeTexture1;
          sampler2D _EdgeTexture2;
          sampler2D _EdgeTexture3;
          sampler2D _EdgeTexture4;
  
          // Simulate mip maps, since we don't have NPOT mip-chains
          float4 getEdgeValue(float2 tsP, int mip)
          {
              float4 coord = float4(tsP + float2(1.0/(2 * mipToSize(mip))),0,0);
  
              if (mip == 0)
              {
                  return tex2Dlod(_EdgeTexture0, coord);
              }
              else if (mip == 1)
              {
                  return tex2Dlod(_EdgeTexture1, coord);
              }
              else if (mip == 2)
              {
                  return tex2Dlod(_EdgeTexture2, coord);
              }
              else if (mip == 3)
              {
                  return tex2Dlod(_EdgeTexture3, coord);
              }
              else
              {
                  return tex2Dlod(_EdgeTexture4, coord);
              }
          }
  
          float2 centerPixel(float2 inputP)
          {
              return floor(inputP - float2(0.5,0.5)) + float2(0.5,0.5);
          }
  
          float2 snapToTexelCenter(float2 inputP, float2 texSize, float2 texSizeInv)
          {
              return centerPixel(inputP * texSize) * texSizeInv;
          }
  
          float4 bilateralUpsampleReflection(float2 tsP, int mip)
          {
              float2 smallTexSize = mipToSize(mip);
              float2 smallPixelPos = tsP * smallTexSize;
              float2 smallPixelPosi = centerPixel(smallPixelPos);
              float2 smallTexSizeInv = 1.0 / smallTexSize;
  
  
              float2 p0 = smallPixelPosi * smallTexSizeInv;
              float2 p3 = (smallPixelPosi + float2(1.0, 1.0)) * smallTexSizeInv;
              float2 p1 = float2(p3.x, p0.y);
              float2 p2 = float2(p0.x, p3.y);
  
              float4 V0 = getReflectionValue(p0.xy, mip);
              float4 V1 = getReflectionValue(p1.xy, mip);
              float4 V2 = getReflectionValue(p2.xy, mip);
              float4 V3 = getReflectionValue(p3.xy, mip);
  
              // Bilateral weights:
              // Bilinear interpolation (filter distance)
              float2  smallPixelPosf  = smallPixelPos - smallPixelPosi;
              float a0 = (1.0 - smallPixelPosf.x) * (1.0 - smallPixelPosf.y);
              float a1 = smallPixelPosf.x * (1.0 - smallPixelPosf.y);
              float a2 = (1.0 - smallPixelPosf.x) * smallPixelPosf.y;
              float a3 = smallPixelPosf.x * smallPixelPosf.y;
  
              float2 fullTexSize = _ReflectionBufferSize;
              float2 fullTexSizeInv = 1.0 / fullTexSize;
  
              float4 hiP0 = float4(snapToTexelCenter(p0, fullTexSize, fullTexSizeInv), 0,0);
              float4 hiP3 = float4(snapToTexelCenter(p3, fullTexSize, fullTexSizeInv), 0,0);
              float4 hiP1 = float4(snapToTexelCenter(p1, fullTexSize, fullTexSizeInv), 0,0);
              float4 hiP2 = float4(snapToTexelCenter(p2, fullTexSize, fullTexSizeInv), 0,0);
  
              float4 tempCenter = tex2Dlod(_NormalAndRoughnessTexture, float4(tsP, 0, 0));
              float3 n  = tempCenter.xyz * 2 - 1;
  
              float4 temp0 = tex2Dlod(_NormalAndRoughnessTexture, hiP0);
              float4 temp1 = tex2Dlod(_NormalAndRoughnessTexture, hiP1);
              float4 temp2 = tex2Dlod(_NormalAndRoughnessTexture, hiP2);
              float4 temp3 = tex2Dlod(_NormalAndRoughnessTexture, hiP3);
  
              float3 n0 = temp0.xyz * 2 - 1;
              float3 n1 = temp1.xyz * 2 - 1;
              float3 n2 = temp2.xyz * 2 - 1;
              float3 n3 = temp3.xyz * 2 - 1;
  
              a0 *= normalWeight(n, n0);
              a1 *= normalWeight(n, n1);
              a2 *= normalWeight(n, n2);
              a3 *= normalWeight(n, n3);
  
              float r = tempCenter.a;
              float r0 = temp0.a;
              float r1 = temp1.a;
              float r2 = temp2.a;
              float r3 = temp3.a;
  
              a0 *= roughnessWeight(r, r0);
              a1 *= roughnessWeight(r, r1);
              a2 *= roughnessWeight(r, r2);
              a3 *= roughnessWeight(r, r3);
  
              // Slightly offset from zero
              a0 = max(a0, 0.001);
              a1 = max(a1, 0.001);
              a2 = max(a2, 0.001);
              a3 = max(a3, 0.001);
  
              // Nearest neighbor
              // a0 = a1 = a2 = a3 = 1.0;
  
              // Normalize the blending weights (weights were chosen so that
              // the denominator can never be zero)
              float norm = 1.0 / (a0 + a1 + a2 + a3);
  
              // Blend
              float4 value = (V0 * a0 + V1 * a1 + V2 * a2 + V3 * a3) * norm;
              //return V0;
              return value;
          }
  
          /** Explicit bilinear fetches; must be used if the reflection buffer is bound using point sampling */
          float4 bilinearUpsampleReflection(float2 tsP, int mip)
          {
              float2 smallTexSize = mipToSize(mip);
              float2 smallPixelPos = tsP * smallTexSize;
              float2 smallPixelPosi = centerPixel(smallPixelPos);
              float2 smallTexSizeInv = 1.0 / smallTexSize;
  
  
              float2 p0 = smallPixelPosi * smallTexSizeInv;
              float2 p3 = (smallPixelPosi + float2(1.0, 1.0)) * smallTexSizeInv;
              float2 p1 = float2(p3.x, p0.y);
              float2 p2 = float2(p0.x, p3.y);
  
              float4 V0 = getReflectionValue(p0.xy, mip);
              float4 V1 = getReflectionValue(p1.xy, mip);
              float4 V2 = getReflectionValue(p2.xy, mip);
              float4 V3 = getReflectionValue(p3.xy, mip);
  
              float a0 = 1.0;
              float a1 = 1.0;
              float a2 = 1.0;
              float a3 = 1.0;
  
              // Bilateral weights:
              // Bilinear interpolation (filter distance)
              float2  smallPixelPosf = smallPixelPos - smallPixelPosi;
              a0 = (1.0 - smallPixelPosf.x) * (1.0 - smallPixelPosf.y);
              a1 = smallPixelPosf.x * (1.0 - smallPixelPosf.y);
              a2 = (1.0 - smallPixelPosf.x) * smallPixelPosf.y;
              a3 = smallPixelPosf.x * smallPixelPosf.y;
  
              // Blend
              float4 value = (V0 * a0 + V1 * a1 + V2 * a2 + V3 * a3);
              return value;
          }
  
          // Unity's roughness is GGX roughness squared
          float roughnessToBlinnPhongExponent(float roughness)
          {
              float r2 = roughness*roughness;
              return 2.0f / r2*r2 - 2.0f;
          }
  
          float glossyLobeSlope(float roughness)
          {
              return pow(roughness, 4.0/3.0);
          }
  
          // Empirically based on our filter:
          //   Mip   | Pixels
          //  --------------
          //    0    |   1          no filter, so single pixel
          //    1    |   17         2r + 1 filter applied once, grabbing from pixels r away in either direction (r=8, four samples times stride of 2)
          //    2    |   50         2r + 1 filter applied on double size pixels, and each of those pixels had reached another r out to the side 2(2r + 1) + m_1
          //    3    |   118        4(2r + 1) + m_2
          //    4    |   254        8(2r + 1) + m_3
          //
          // Approximated by pixels = 16*2^mip-15
          // rearranging we get mip = log_2((pixels + 15) / 16)
          //
          float filterFootprintInPixelsToMip(float footprint)
          {
              return log2((footprint + 15) / 16);
          }
  
          float3 ansiGradient(float t)
          {
              //return float3(t, t, t);
              return fmod(floor(t * float3(8.0, 4.0, 2.0)), 2.0);
          }
  
          float4 fragCompositeSSR(v2f i) : SV_Target
          {
              // Pixel being shaded
              float2 tsP = i.uv2.xy;
  
              float roughness = 1.0-tex2D(_CameraGBufferTexture1, tsP).a;
  
              float rayDistance = tex2D(_HitPointTexture, tsP).z;
  
              // Get the camera space position of the reflection hit
              float3 csPosition = GetPosition(tsP);
              float3 wsNormal = tex2D(_CameraGBufferTexture2, tsP).rgb * 2.0 - 1.0;
              float3 csN = mul((float3x3)(_WorldToCameraMatrix), wsNormal);
              float3 c_mi = csMirrorVector(csPosition, csN);
              float3 csHitpoint = c_mi * rayDistance + csPosition;
  
  
              float gatherFootprintInMeters = glossyLobeSlope(roughness) * rayDistance;
              // We could add a term that incorporates the normal
              // This approximation assumes reflections happen at a glancing angle
              float filterFootprintInPixels = gatherFootprintInMeters * _PixelsPerMeterAtOneMeter / csHitpoint.z;
              if (_HalfResolution == 1)
              {
                  filterFootprintInPixels *= 0.5;
              }
  
              float mip = filterFootprintInPixelsToMip(filterFootprintInPixels);
  
              float nonPhysicalMip = pow(roughness, 3.0 / 4.0) * UNITY_SPECCUBE_LOD_STEPS;
  
              if (_HalfResolution == 1)
              {
                  nonPhysicalMip = nonPhysicalMip * 0.7;
              }
  
              mip = max(0, min(4, mip));
  
              float4 result = 0.;
  
              {
                  int mipMin = int(mip);
                  int mipMax = min(mipMin + 1, 4);
                  float mipLerp = mip-mipMin;
  
                  if (_BilateralUpsampling == 1)
                  {
                      result = lerp(bilateralUpsampleReflection(tsP, mipMin), bilateralUpsampleReflection(tsP, mipMax), mipLerp);
                  }
                  else
                  {
                      float4 minResult = getReflectionValue(tsP, mipMin);
                      float4 maxResult = getReflectionValue(tsP, mipMax);
                      result = lerp(minResult, maxResult, mipLerp);
                      result.a = min(minResult.a, maxResult.a);
                  }
              }
  
              result.a = min(result.a, 1.0);
              float vignette = applyEdgeFade(tsP, _ScreenEdgeFading);
              result.a *= vignette;
  
  
              // THIS MIGHT BE SLIGHTLY WRONG, TRY STEP()
              float alphaModifier = 1.0 - clamp(roughness * .3, 0., 1.);
              result.a *= alphaModifier;
              return result;
          }
  
          int _LastMip;
  
          float4 fragMin(v2f i) : SV_Target
          {
              float2 tsP = i.uv2.xy;
              float2 lastTexSize = mipToSize(_LastMip);
              float2 lastTexSizeInv = 1.0 / lastTexSize;
              float2 p00 = snapToTexelCenter(tsP, lastTexSize, lastTexSizeInv);
              float2 p11 = p00 + lastTexSizeInv;
  
              return min(
                  min(tex2D(_MainTex, p00), tex2D(_MainTex, p11)),
                  min(tex2D(_MainTex, float2(p00.x, p11.y)), tex2D(_MainTex, float2(p11.x, p00.y)))
              );
          }
  
          float4 fragResolveHitPoints(v2f i) : SV_Target
          {
              float2 tsP = i.uv2.xy;
              float4 temp = tex2D(_HitPointTexture, tsP);
              float2 hitPoint = temp.xy;
              float confidence = temp.w;
              float3 colorResult = confidence > 0.0 ? tex2D(_MainTex, hitPoint).rgb : tex2D(_CameraReflectionsTexture, tsP).rgb;
  
              if (any(isnan(colorResult)))
                  colorResult = float3(0.0, 0.0, 0.0);
  
              // As of 11/29/2015, on Unity 5.3 on a Windows 8.1 computer with a NVIDIA GeForce 980,
              // with driver 347.62, the above check does not actually work to get rid of NaNs!
              // So we add this "redundant" check.
              if (!all(isfinite(colorResult)))
                  colorResult = float3(0.0, 0.0, 0.0);
  
              return float4(colorResult, confidence);
          }
  
          float4 fragBilatKeyPack(v2f i) : SV_Target
          {
              float2 tsP = i.uv2.xy;
              float3 csN = tex2D(_CameraGBufferTexture2, tsP).xyz;
              float roughness = tex2D(_CameraGBufferTexture1, tsP).a;
              return float4(csN, roughness);
          }
  
          float4 fragDepthToCSZ(v2f i) : SV_Target
          {
              float depth = SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture, i.uv2.xy);
              return float4(-LinearEyeDepth(depth), 0.0, 0.0, 0.0);
          }
  
          static const int NUM_POISSON_TAPS = 12;
          // Same as used in CameraMotionBlur.shader
          static const float2 poissonSamples[NUM_POISSON_TAPS] =
          {
              float2(-0.326212,-0.40581),
              float2(-0.840144,-0.07358),
              float2(-0.695914,0.457137),
              float2(-0.203345,0.620716),
              float2(0.96234,-0.194983),
              float2(0.473434,-0.480026),
              float2(0.519456,0.767022),
              float2(0.185461,-0.893124),
              float2(0.507431,0.064425),
              float2(0.89642,0.412458),
              float2(-0.32194,-0.932615),
              float2(-0.791559,-0.59771)
          };
  
          float4 fragFilterSharpReflections(v2f i) : SV_Target
          {
              // Could improve perf by not computing blur when we won't be sampling the highest level anyways
              float2 tsP = i.uv2.xy;
              float4 sum = 0.0;
              float sampleRadius = _MainTex_TexelSize.xy * _ReflectionBlur;
  
              for (int i = 0; i < NUM_POISSON_TAPS; i++)
              {
                  float2 p = tsP + poissonSamples[i] * sampleRadius;
  
                  float4 tap = tex2D(_MainTex, p);
                  if (_HighlightSuppression)
                  {
                      tap.rgb = highlightCompression(tap.rgb);
                  }
  
                  sum += tap;
              }
  
              float4 result = sum / float(NUM_POISSON_TAPS);
  
              if (_HighlightSuppression)
              {
                  result.rgb = highlightDecompression(result.rgb);
              }
  
              return result;
          }
  
      ENDCG
  
      SubShader
      {
          ZTest Always Cull Off ZWrite Off
  
          // 0: Raytrace
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragRaytrace1
  
                  float4 fragRaytrace1(v2f i) : SV_Target
                  {
                      return fragRaytrace(i, _RayStepSize);
                  }
              ENDCG
          }
  
          // 1: Composite
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragComposite
              ENDCG
          }
  
          // 2: GBlur
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragGBlur
              ENDCG
          }
  
          // 3: CompositeSSR
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragCompositeSSR
              ENDCG
          }
  
          // 4: Min mip generation
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragMin
              ENDCG
          }
  
          // 5: Hit point texture to reflection buffer
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragResolveHitPoints
              ENDCG
          }
  
          // 6: Pack Bilateral Filter Keys in single buffer
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragBilatKeyPack
              ENDCG
          }
  
          // 7: Blit depth information as camera space Z
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragDepthToCSZ
              ENDCG
          }
  
          // 8: Filter the highest quality reflection buffer
          Pass
          {
              CGPROGRAM
                  #pragma exclude_renderers gles xbox360 ps3
                  #pragma vertex vert
                  #pragma fragment fragFilterSharpReflections
              ENDCG
          }
      }
  
      Fallback "Diffuse"
  }