New Depth of Field - Minor improvements, optimizations, and now works with auto focus

Signed-off-by: antonmic <56370189+antonmic@users.noreply.github.com>

Gems/Atom/Feature/Common/Assets/Passes/NewDepthOfField.pass

@@ -18,6 +18,19 @@
                 }
             ],
             "PassRequests": [
+                {
+                    "Name": "AutoFocus",
+                    "TemplateName": "DepthOfFieldReadBackFocusDepthTemplate",
+                    "Connections": [
+                        {
+                            "LocalSlot": "DepthInput",
+                            "AttachmentRef": {
+                                "Pass": "Parent",
+                                "Attachment": "Depth"
+                            }
+                        }
+                    ]
+                },
                 {
                     "Name": "Downsample",
                     "TemplateName": "NewDepthOfFieldDownsampleTemplate",

Gems/Atom/Feature/Common/Assets/Shaders/PostProcessing/NewDepthOfFieldFilterLarge.azsl

@@ -85,6 +85,24 @@ PSOutput MainPS(VSOutput IN)
 
     float4 backgroundColor = float4(0, 0, 0, 0);
     
+    if(minCoc >= 0)
+    {
+        for(uint i = 0; i < SAMPLES_LOOP_TOTAL; ++i)
+        {
+            // Calculate sample offset
+            float3 offset = GetOffsetUV(i, offsetMultiplier);
+            
+            // Get sample
+            float4 sampleColorCoc = PassSrg::m_colorAndCoc.Sample(PassSrg::LinearSampler, pixelUV + offset.xy).rgba;
+
+            // Calculate weight for sample
+            float weight = CaclulateWeight(offset.z, cocRadius, sampleColorCoc.a, centerCoc);
+
+            // Accumulate
+            color += weight * sampleColorCoc;
+        }
+    }
+    else
     {
         float backgroundMin = min(0, centerCoc);
         color.rgb /= abs(color.a);
@@ -112,17 +130,15 @@ PSOutput MainPS(VSOutput IN)
             backgroundColor += isBackground * sampleColorCoc;
             color += !isBackground * sampleColorCoc;
         }
+
+        backgroundColor.rgb /= max(backgroundColor.a, COC_EPSILON);
     }
     
-    float backgroundRatio = backgroundColor.a / float(SAMPLES_LOOP_TOTAL);
+    float backgroundRatio = saturate( backgroundColor.a / float(SAMPLES_LOOP_TOTAL) );
     float alpha = backgroundRatio > abs(centerCoc) ? -backgroundRatio : centerCoc;
 
     color.rgb /= max(color.a, COC_EPSILON);
-    backgroundColor.rgb /= max(backgroundColor.a, COC_EPSILON);
-    
-    color = color * saturate(1 - backgroundRatio) + backgroundColor * backgroundRatio;
-    //color.rgb += backgroundColor.rgb;
-
+    color = lerp(color, backgroundColor, backgroundRatio);
 
 
     PSOutput OUT = (PSOutput)0;

Gems/Atom/Feature/Common/Assets/Shaders/PostProcessing/NewDepthOfFieldFilterSmall.azsl

@@ -31,6 +31,16 @@ ShaderResourceGroup PassSrg : SRG_PerPass
         AddressV = Clamp;
         AddressW = Clamp;
     };
+
+    Sampler PointSampler
+    {
+        MinFilter = Point;
+        MagFilter = Point;
+        MipFilter = Point;
+        AddressU = Clamp;
+        AddressV = Clamp;
+        AddressW = Clamp;
+    };
 }
 
 float2 GetOffsetUV(uint index, float2 offsetMultiplier)
@@ -44,7 +54,7 @@ PSOutput MainPS(VSOutput IN)
     float2 pixelUV = IN.m_texCoord.xy;
 
     // Sample pixel being shaded
-    float4 centerSample = PassSrg::m_colorAndCoc.Sample(PassSrg::LinearSampler, pixelUV).rgba;
+    float4 centerSample = PassSrg::m_colorAndCoc.Sample(PassSrg::PointSampler, pixelUV).rgba;
     float centerCoc = centerSample.a;
 
     // Aspect ratio = texture.x / texture.y = dimensions.x * dimensions.w
@@ -65,7 +75,7 @@ PSOutput MainPS(VSOutput IN)
         float2 offsetUV = GetOffsetUV(i, offsetMultiplier);
 
         // Get sample
-        float4 sampleColorCoc = PassSrg::m_colorAndCoc.Sample(PassSrg::LinearSampler, pixelUV + offsetUV).rgba;
+        float4 sampleColorCoc = PassSrg::m_colorAndCoc.Sample(PassSrg::PointSampler, pixelUV + offsetUV).rgba;
 
         // Calculate weight
         float cocDiff = sampleColorCoc.a - centerCoc;
@@ -85,4 +95,3 @@ PSOutput MainPS(VSOutput IN)
     OUT.m_color.a = centerCoc;
     return OUT;
 }
-

Gems/Atom/Feature/Common/Code/Source/PostProcessing/NewDepthOfFieldPasses.cpp

@@ -149,6 +149,14 @@ namespace AZ
                 float radius = (loop + 1.0f) / float(NewDepthOfFieldConstants::numberOfLoops);
                 float loopCount = NewDepthOfFieldConstants::loopCounts[loop];
 
+                float angleOffset = 0;
+
+                // Every other loop slightly rotate sample ring so they don't line up
+                if (loop & 1)
+                {
+                    angleOffset = Constants::TwoPi * 0.5f / loopCount;
+                }
+
                 for (float i = 0.0f; i < loopCount; ++i)
                 {
                     float angle = Constants::TwoPi * i / loopCount;