Probe Volumes: Lots of bugfixes and improvements to bilateral filteri…

…ng modes. Octahedral Depth data now working (requires changes on the C++ side). Added support for comparing filtering the texel coordinates and then taking a single sample, vs taking 8x samples and then filtering the results. Still a WIP

com.unity.render-pipelines.high-definition-config/Runtime/ShaderConfig.cs

@@ -49,6 +49,19 @@ public enum ProbeVolumesBilateralFilteringModes
         OctahedralDepth = 2
     }
 
+    /// <summary>
+    /// Options for the mode HDRP uses for probe volume bilateral filtering.
+    /// </summary>
+    ///<seealso cref="ShaderOptions"/>
+    [GenerateHLSL(PackingRules.Exact)]
+    public enum ProbeVolumesBilateralFilteringSampleModes
+    {
+        /// <summary>Bilateral filtering blends weighted texture coordinates, and then takes a single hardware filtered sample from the atlas. Reduces texture sample bandwidth at the cost of inexact bilateral filter reconstruction, and hardware interpolation precision banding.</summary>
+        ApproximateSample = 0,
+        /// <summary>Bilateral filtering loads 8x taps from the atlas, and weights these results. Reconstructs precise bilateral filter results at the potential cost of bandwidth.</summary>
+        PreciseLoad = 1
+    }
+
     /// <summary>
     /// Project-wide shader configuration options.
     /// </summary>
@@ -85,15 +98,18 @@ public enum ShaderOptions
 
         /// <summary>The probe volume evaluation mode.</summary>
         /// <seealso cref = "ProbeVolumesEvaluationModes " />
-        ProbeVolumesEvaluationMode = ProbeVolumesEvaluationModes.Disabled,
+        ProbeVolumesEvaluationMode = ProbeVolumesEvaluationModes.LightLoop,
         /// <summary>Probe volume supports additive blending.</summary>
         ProbeVolumesAdditiveBlending = 1,
         /// <summary>The probe volume filtering mode.</summary>
         /// <seealso cref="ProbeVolumesBilateralFilteringModes"/>
-        ProbeVolumesBilateralFilteringMode = ProbeVolumesBilateralFilteringModes.Validity,
+        ProbeVolumesBilateralFilteringMode = ProbeVolumesBilateralFilteringModes.OctahedralDepth,
+        /// <summary>The probe volume bilateral filtering sample mode.</summary>
+        /// <seealso cref="ProbeVolumesBilateralFilteringSampleModes"/>
+        ProbeVolumesBilateralFilteringSampleMode = ProbeVolumesBilateralFilteringSampleModes.PreciseLoad,
         /// <summary>The probe volume encoding method.</summary>
-        /// /// <seealso cref="ProbeVolumesEncodingModes"/>
-        ProbeVolumesEncodingMode = ProbeVolumesEncodingModes.SphericalHarmonicsL1,
+        /// <seealso cref="ProbeVolumesEncodingModes"/>
+        ProbeVolumesEncodingMode = ProbeVolumesEncodingModes.SphericalHarmonicsL2,
 
         /// <summary>Support for area lights.</summary>
         AreaLights = 1,
@@ -136,6 +152,9 @@ public class ShaderConfig
         /// <summary>Specifies the probe volume filtering mode.</summary>
         ///<seealso cref="ShaderOptions.ProbeVolumesBilateralFilteringMode"/>
         public static ProbeVolumesBilateralFilteringModes s_ProbeVolumesBilateralFilteringMode = (ProbeVolumesBilateralFilteringModes)ShaderOptions.ProbeVolumesBilateralFilteringMode;
+        /// <summary>Specifies the probe volume filtering mode.</summary>
+        ///<seealso cref="ShaderOptions.ProbeVolumesBilateralFilteringMode"/>
+        public static ProbeVolumesBilateralFilteringSampleModes s_ProbeVolumesBilateralFilteringSampleMode = (ProbeVolumesBilateralFilteringSampleModes)ShaderOptions.ProbeVolumesBilateralFilteringSampleMode;
         /// <summary>Specifies the probe volume encoding method.</summary>
         ///<seealso cref="ShaderOptions.ProbeVolumesEncodingMode"/>
         public static ProbeVolumesEncodingModes s_ProbeVolumesEncodingMode = (ProbeVolumesEncodingModes)ShaderOptions.ProbeVolumesEncodingMode;

com.unity.render-pipelines.high-definition-config/Runtime/ShaderConfig.cs.hlsl

@@ -25,6 +25,12 @@
 #define PROBEVOLUMESBILATERALFILTERINGMODES_VALIDITY (1)
 #define PROBEVOLUMESBILATERALFILTERINGMODES_OCTAHEDRAL_DEPTH (2)
 
+//
+// UnityEngine.Rendering.HighDefinition.ProbeVolumesBilateralFilteringModes:  static fields
+//
+#define PROBEVOLUMESBILATERALFILTERINGSAMPLEMODES_APPROXIMATE_SAMPLE (0)
+#define PROBEVOLUMESBILATERALFILTERINGSAMPLEMODES_PRECISE_LOAD (1)
+
 //
 // UnityEngine.Rendering.HighDefinition.ShaderOptions:  static fields
 //
@@ -33,10 +39,11 @@
 #define SHADEROPTIONS_PRE_EXPOSITION (1)
 #define SHADEROPTIONS_PRECOMPUTED_ATMOSPHERIC_ATTENUATION (0)
 #define SHADEROPTIONS_XR_MAX_VIEWS (2)
-#define SHADEROPTIONS_PROBE_VOLUMES_EVALUATION_MODE (0)
+#define SHADEROPTIONS_PROBE_VOLUMES_EVALUATION_MODE (1)
 #define SHADEROPTIONS_PROBE_VOLUMES_ADDITIVE_BLENDING (1)
-#define SHADEROPTIONS_PROBE_VOLUMES_BILATERAL_FILTERING_MODE (1)
-#define SHADEROPTIONS_PROBE_VOLUMES_ENCODING_MODE (1)
+#define SHADEROPTIONS_PROBE_VOLUMES_BILATERAL_FILTERING_MODE (2)
+#define SHADEROPTIONS_PROBE_VOLUMES_BILATERAL_FILTERING_SAMPLE_MODE (1)
+#define SHADEROPTIONS_PROBE_VOLUMES_ENCODING_MODE (2)
 #define SHADEROPTIONS_AREA_LIGHTS (1)
 #define SHADEROPTIONS_BARN_DOOR (0)
 

com.unity.render-pipelines.high-definition/Editor/Lighting/ProbeVolume/ProbeVolumeUI.Drawer.cs

@@ -130,6 +130,20 @@ static void Drawer_ToolBar(SerializedProbeVolume serialized, Editor owner)
         static void Drawer_PrimarySettings(SerializedProbeVolume serialized, Editor owner)
         {
             EditorGUILayout.PropertyField(serialized.drawProbes, Styles.s_DrawProbesLabel);
+            EditorGUILayout.PropertyField(serialized.drawOctahedralDepthRays, Styles.s_DrawOctahedralDepthRays);
+            if (serialized.drawOctahedralDepthRays.boolValue)
+            {
+                EditorGUI.BeginChangeCheck();
+                EditorGUILayout.DelayedIntField(serialized.drawOctahedralDepthRayIndexX, Styles.s_DrawOctahedralDepthRayIndexX);
+                EditorGUILayout.DelayedIntField(serialized.drawOctahedralDepthRayIndexY, Styles.s_DrawOctahedralDepthRayIndexY);
+                EditorGUILayout.DelayedIntField(serialized.drawOctahedralDepthRayIndexZ, Styles.s_DrawOctahedralDepthRayIndexZ);
+                if (EditorGUI.EndChangeCheck())
+                {
+                    serialized.drawOctahedralDepthRayIndexX.intValue = Mathf.Clamp(serialized.drawOctahedralDepthRayIndexX.intValue, 0, serialized.resolutionX.intValue - 1);
+                    serialized.drawOctahedralDepthRayIndexY.intValue = Mathf.Clamp(serialized.drawOctahedralDepthRayIndexY.intValue, 0, serialized.resolutionY.intValue - 1);
+                    serialized.drawOctahedralDepthRayIndexZ.intValue = Mathf.Clamp(serialized.drawOctahedralDepthRayIndexZ.intValue, 0, serialized.resolutionZ.intValue - 1);
+                }
+            }
             EditorGUILayout.PropertyField(serialized.probeSpacingMode, Styles.s_ProbeSpacingModeLabel);
             switch ((ProbeSpacingMode)serialized.probeSpacingMode.enumValueIndex)
             {

com.unity.render-pipelines.high-definition/Editor/Lighting/ProbeVolume/ProbeVolumeUI.Skin.cs

@@ -25,6 +25,11 @@ internal static class Styles
             internal static readonly GUIContent s_Size = new GUIContent("Size", "Modify the size of this Probe Volume. This is independent of the Transform's Scale.");
             internal static readonly GUIContent s_DebugColorLabel = new GUIContent("Debug Color", "This color is used to visualize per-pixel probe volume weights in the render pipeline debugger.");
             internal static readonly GUIContent s_DrawProbesLabel = new GUIContent("Draw Probes", "Enable or disable drawing probes.");
+            internal static readonly GUIContent s_DrawOctahedralDepthRays = new GUIContent("Draw Octahedral Depth Rays", "Enable or disable drawing rays to visualize to the octahedral depth data.");
+            internal static readonly GUIContent s_DrawOctahedralDepthRayIndexX = new GUIContent("Octahedral Depth Rays Probe X", "Specifies the x index of the probe to visualize octahedral depth rays for.");
+            internal static readonly GUIContent s_DrawOctahedralDepthRayIndexY = new GUIContent("Octahedral Depth Rays Probe Y", "Specifies the y index of the probe to visualize octahedral depth rays for.");
+            internal static readonly GUIContent s_DrawOctahedralDepthRayIndexZ = new GUIContent("Octahedral Depth Rays Probe Z", "Specifies the z index of the probe to visualize octahedral depth rays for.");
+
             internal static readonly GUIContent s_BlendLabel = new GUIContent("Blend Distance", "Interior distance from the Size where the contribution fades in completely.");
             internal static readonly GUIContent s_NormalModeContent = new GUIContent("Normal", "Exposes standard parameters.");
             internal static readonly GUIContent s_AdvancedModeContent = new GUIContent("Advanced", "Exposes advanced parameters.");

com.unity.render-pipelines.high-definition/Editor/Lighting/ProbeVolume/SerializedProbeVolume.cs

@@ -6,6 +6,10 @@ class SerializedProbeVolume
         internal SerializedProperty probeVolumeAsset;
         internal SerializedProperty debugColor;
         internal SerializedProperty drawProbes;
+        internal SerializedProperty drawOctahedralDepthRays;
+        internal SerializedProperty drawOctahedralDepthRayIndexX;
+        internal SerializedProperty drawOctahedralDepthRayIndexY;
+        internal SerializedProperty drawOctahedralDepthRayIndexZ;
 
         internal SerializedProperty probeSpacingMode;
 
@@ -48,6 +52,11 @@ internal SerializedProbeVolume(SerializedObject serializedObject)
             debugColor = probeVolumeParams.FindPropertyRelative("debugColor");
             drawProbes = probeVolumeParams.FindPropertyRelative("drawProbes");
 
+            drawOctahedralDepthRays = probeVolumeParams.FindPropertyRelative("drawOctahedralDepthRays");
+            drawOctahedralDepthRayIndexX = probeVolumeParams.FindPropertyRelative("drawOctahedralDepthRayIndexX");
+            drawOctahedralDepthRayIndexY = probeVolumeParams.FindPropertyRelative("drawOctahedralDepthRayIndexY");
+            drawOctahedralDepthRayIndexZ = probeVolumeParams.FindPropertyRelative("drawOctahedralDepthRayIndexZ");
+
             probeSpacingMode = probeVolumeParams.FindPropertyRelative("probeSpacingMode");
 
             resolutionX = probeVolumeParams.FindPropertyRelative("resolutionX");

com.unity.render-pipelines.high-definition/Runtime/Lighting/LightLoop/Deferred.compute

@@ -1,3 +1,4 @@
+#pragma enable_d3d11_debug_symbols
 #pragma kernel Deferred_Direct_Fptl                                SHADE_OPAQUE_ENTRY=Deferred_Direct_Fptl
 #pragma kernel Deferred_Direct_Fptl_DebugDisplay                   SHADE_OPAQUE_ENTRY=Deferred_Direct_Fptl_DebugDisplay             DEBUG_DISPLAY
 

com.unity.render-pipelines.high-definition/Runtime/Lighting/ProbeVolume/DebugDisplayProbeVolume.shader

@@ -19,6 +19,7 @@ Shader "Hidden/ScriptableRenderPipeline/DebugDisplayProbeVolume"
         float3  _TextureViewResolution;
         float2  _ValidRange;
         int _ProbeVolumeAtlasSliceMode;
+        float4 _AtlasTextureOctahedralDepthScaleBias;
         // float   _RcpGlobalScaleFactor;
         SamplerState ltc_linear_clamp_sampler;
 
@@ -105,8 +106,9 @@ Shader "Hidden/ScriptableRenderPipeline/DebugDisplayProbeVolume"
 
                 float valueValidity = saturate((ProbeVolumeSampleValidity(uvw) - _ValidRange.x) * _ValidRange.y);
 
-            #if SHADEROPTIONS_PROBE_VOLUMES_BILATERAL_FILTERING == PROBEVOLUMESBILATERALFILTERINGMODES_OCTAHEDRAL_DEPTH
-                float2 valueOctahedralDepthMeanAndVariance = saturate((SAMPLE_TEXTURE2D_LOD(_AtlasTextureOctahedralDepth, ltc_linear_clamp_sampler, input.texcoord * _AtlasTextureOctahedralDepthScaleBias.xy + _AtlasTextureOctahedralDepthScaleBias.zw, 0).xy - _ValidRange.x) * _ValidRange.y);
+            #if SHADEROPTIONS_PROBE_VOLUMES_BILATERAL_FILTERING_MODE == PROBEVOLUMESBILATERALFILTERINGMODES_OCTAHEDRAL_DEPTH
+                float4 scaleBias = _AtlasTextureOctahedralDepthScaleBias;
+                float2 valueOctahedralDepthMeanAndMeanSquared = saturate((SAMPLE_TEXTURE2D_LOD(_ProbeVolumeAtlasOctahedralDepth, ltc_linear_clamp_sampler, input.texcoord * scaleBias.xy + scaleBias.zw, 0).xy - _ValidRange.x) * _ValidRange.y);
             #endif
 
                 switch (_ProbeVolumeAtlasSliceMode)
@@ -164,11 +166,13 @@ Shader "Hidden/ScriptableRenderPipeline/DebugDisplayProbeVolume"
 
                     case PROBEVOLUMEATLASSLICEMODE_OCTAHEDRAL_DEPTH:
                     {
-                    #if SHADEROPTIONS_PROBE_VOLUMES_BILATERAL_FILTERING == PROBEVOLUMESBILATERALFILTERINGMODES_OCTAHEDRAL_DEPTH
-                        // Tonemap variance with sqrt() to bring it into a more similar scale to mean to make it more readable.
+                    #if SHADEROPTIONS_PROBE_VOLUMES_BILATERAL_FILTERING_MODE == PROBEVOLUMESBILATERALFILTERINGMODES_OCTAHEDRAL_DEPTH
+                        float mean = valueOctahedralDepthMeanAndMeanSquared.x;
+                        float meanSquared = valueOctahedralDepthMeanAndMeanSquared.y;
+                        float variance = meanSquared - mean * mean;
                         return float4(
-                            valueOctahedralDepthMeanAndVariance.x,
-                            (valueOctahedralDepthMeanAndVariance.y > 0.0f) ? sqrt(valueOctahedralDepthMeanAndVariance.y) : 0.0f,
+                            mean,
+                            variance,
                             0.0f,
                             1.0f
                         );