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Assets/ScriptableRenderLoop/HDRenderLoop/Material/Lit/Lit.hlsl

 
     float3 unL = positionWS - lightData.positionWS;
 
-    // Pick the axis along which to expand the fade-out sphere into an ellipsoid.
+    // Pick the axis along which to dilate the attenuation sphere into an ellipsoid.
-    // We define the ellipsoid s.t. r1 = r, r2 = (r + len / 2).
+    // We define the ellipsoid s.t. r1 = r2 = r, r3 = (r + len / 2).
     // TODO: This could be precomputed.
     float radius         = rsqrt(lightData.invSqrAttenuationRadius);
     float invAspectRatio = radius / (radius + (0.5 * len));
 
     float3 unL = positionWS - lightData.positionWS;
 
-    // Pick the axis along which to expand the fade-out sphere into an ellipsoid.
+    // Pick the axis along which to dilate the attenuation sphere into an ellipsoid.
-    // We define the ellipsoid s.t. r1 = r, r2 = (r + |w - h| / 2).
+    // We define the ellipsoid s.t. r1 = r2 = r, r3 = (r + |w - h| / 2).
     // TODO: This could be precomputed.
     float radius         = rsqrt(lightData.invSqrAttenuationRadius);
     float invAspectRatio = radius / (radius + abs(halfWidth - halfHeight));

Assets/ScriptableRenderLoop/ShaderLibrary/CommonLighting.hlsl

     return attenuation;
 }
 
-// Applies SmoothDistanceAttenuation() after stretching the fade-out sphere of the given radius
-// into an ellipsoid with the specified aspect ratio and the longest axis.
+// Applies SmoothDistanceAttenuation() after stretching the attenuation sphere of the
+// given radius into an ellipsoid with the specified aspect ratio and the longest axis.
-    // Project the unnormalized light vector onto the expansion axis.
+    // Project the unnormalized light vector onto the dilation axis.
-    // It is equivalent to the expansion of the fade-out sphere into an ellipsoid.
+    // It is equivalent to stretching the attenuation sphere into an ellipsoid.
     float scale = projL - projL * invAspectRatio;
     unL -= scale * axis;