From 291711ee24bf79f3da31c2079e756b7901e77fb3 Mon Sep 17 00:00:00 2001
From: Olivier Prat <olivier@zvork.fr>
Date: Thu, 7 Dec 2017 13:41:36 +0100
Subject: [PATCH] Fixed weird black pixel bugs in TAA due to sqrt in TAA shader
 with very slightly negative number when computing color variance

---
 libraries/render-utils/src/taa.slf |  8 ++++----
 libraries/render-utils/src/taa.slh | 14 +++++++-------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/libraries/render-utils/src/taa.slf b/libraries/render-utils/src/taa.slf
index 9334d2a5e7..b4ad713a7a 100644
--- a/libraries/render-utils/src/taa.slf
+++ b/libraries/render-utils/src/taa.slf
@@ -31,11 +31,11 @@ void main() {
     }
 
     // Debug region before debug or fxaa region X
-    float distToRegionFXAA = fragUV.x - taa_getRegionFXAA().x;  
+/*    float distToRegionFXAA = fragUV.x - taa_getRegionFXAA().x;  
     if (distToRegionFXAA > 0.0) {
         outFragColor = vec4(taa_evalFXAA(fragUV), 1.0);
         return;
-    }
+    }*/
 
    // vec3 nearFragUV = taa_findClosestFragment3x3(fragUV);
    // vec2 fragVel = taa_fetchVelocityMap(nearFragUV.xy);
@@ -46,13 +46,13 @@ void main() {
 
     vec3 sourceColor;
     vec3 historyColor;
-    vec2 prevFragUV = taa_fetchSourceAndHistory(fragUV, fragVel, fragJitterPix, sourceColor, historyColor);
+    vec2 prevFragUV = taa_fetchSourceAndHistory(fragUV, fragVel, sourceColor, historyColor);
 
     vec3 nextColor = sourceColor;
  
      if (taa_constrainColor()) {
         // clamp history to neighbourhood of current sample
-        historyColor = taa_evalConstrainColor(sourceColor, fragUV, fragVel, fragDepth, fragJitterPix, historyColor);
+        historyColor = taa_evalConstrainColor(sourceColor, fragUV, fragVel, fragDepth, historyColor);
     }
     
     if (taa_feedbackColor()) {
diff --git a/libraries/render-utils/src/taa.slh b/libraries/render-utils/src/taa.slh
index 4e5f0e76ba..d276f2870d 100644
--- a/libraries/render-utils/src/taa.slh
+++ b/libraries/render-utils/src/taa.slh
@@ -255,7 +255,7 @@ vec3 taa_fetchVelocityMapBest(vec2 uv) {
     return vec3(best.xy, taa_fetchDepth(uv));
 }
 
-vec2 taa_fetchSourceAndHistory(vec2 fragUV, vec2 fragVelocity, vec2 fragJitterPix, out vec3 sourceColor, out vec3 historyColor) {
+vec2 taa_fetchSourceAndHistory(vec2 fragUV, vec2 fragVelocity, out vec3 sourceColor, out vec3 historyColor) {
     sourceColor = taa_fetchSourceMap(fragUV).xyz;
 
     vec2 prevFragUV = fragUV - fragVelocity;
@@ -272,7 +272,7 @@ float Luminance(vec3 rgb) {
 
 #define MINMAX_3X3_ROUNDED 1
 
-mat3 taa_evalNeighbourColorVariance(vec3 sourceColor, vec2 fragUV, vec2 fragVelocity, float fragZe, vec2 fragJitterPix) {
+mat3 taa_evalNeighbourColorVariance(vec3 sourceColor, vec2 fragUV, vec2 fragVelocity, float fragZe) {
     vec2 texelSize = taa_getTexelSize();
  
 
@@ -317,7 +317,7 @@ mat3 taa_evalNeighbourColorVariance(vec3 sourceColor, vec2 fragUV, vec2 fragVelo
 
     
     vec3 mu = sumSamples / vec3(9.0);
-    vec3 sigma = sqrt(sumSamples2 / vec3(9.0) - mu * mu);
+    vec3 sigma = sqrt(max(sumSamples2 / vec3(9.0) - mu * mu, vec3(0)));
     
        float gamma = params.covarianceGamma;
        vec3 cmin = mu - gamma * sigma;
@@ -326,7 +326,7 @@ mat3 taa_evalNeighbourColorVariance(vec3 sourceColor, vec2 fragUV, vec2 fragVelo
    return mat3(cmin, cmax, mu);
 }
 
-mat3 taa_evalNeighbourColorRegion(vec3 sourceColor, vec2 fragUV, vec2 fragVelocity, float fragZe, vec2 fragJitterPix) {
+mat3 taa_evalNeighbourColorRegion(vec3 sourceColor, vec2 fragUV, vec2 fragVelocity, float fragZe) {
     vec2 imageSize = taa_getImageSize();
     vec2 texelSize = taa_getTexelSize();
     vec3 cmin, cmax, cavg;
@@ -463,13 +463,13 @@ vec3 taa_clampColor(vec3 colorMin, vec3 colorMax, vec3 colorSource, vec3 color)
 	//}
 }
 
-vec3 taa_evalConstrainColor(vec3 sourceColor, vec2 sourceUV, vec2 sourceVel, float sourceZe, vec2 sourceJitterPix, vec3 candidateColor) {
+vec3 taa_evalConstrainColor(vec3 sourceColor, vec2 sourceUV, vec2 sourceVel, float sourceZe, vec3 candidateColor) {
     mat3 colorMinMaxAvg;
 
     if (taa_covarianceClipColor()) {
-        colorMinMaxAvg = taa_evalNeighbourColorVariance(sourceColor, sourceUV, sourceVel, sourceZe, sourceJitterPix);
+        colorMinMaxAvg = taa_evalNeighbourColorVariance(sourceColor, sourceUV, sourceVel, sourceZe);
     } else {
-        colorMinMaxAvg = taa_evalNeighbourColorRegion(sourceColor, sourceUV, sourceVel, sourceZe, sourceJitterPix);
+        colorMinMaxAvg = taa_evalNeighbourColorRegion(sourceColor, sourceUV, sourceVel, sourceZe);
     }
      
 	// clamp history to neighbourhood of current sample