NRD updated to v3.7.0:

- PT: added multi-bounce delta events (reflections and refraction on glass)
- PT: fixed wrong output for INF pixels in the checkerboard mode
- fixed "check me" and "improve me" tests colorization (which is currently for Bistro Interior only)
- set FORCE_OPAQUE for all materials except alpha-opaque
- updated dependencies

Author: dzhdanNV

CMakeLists.txt

@@ -73,8 +73,8 @@ if ((CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64") OR (CMAKE_SYSTEM_PROCESSOR MATCHE
 endif()
 
 # Shader compilation
-set(NRD_USE_OCT_NORMAL_ENCODING "1" CACHE STRING "NRD_USE_OCT_NORMAL_ENCODING")
-set(NRD_USE_MATERIAL_ID "1" CACHE STRING "NRD_USE_MATERIAL_ID")
+set(NRD_NORMAL_ENCODING "2" CACHE STRING "Normal encoding variant (0-4, matches NRD_NORMAL_ENCODING from NRD)")
+set(NRD_ROUGHNESS_ENCODING "1" CACHE STRING "Roughness encoding variant (0-2, matches NRD_ROUGHNESS_ENCODING from NRD)")
 
 if (NOT DISABLE_SHADER_COMPILATION)
     # Include path for DXC and FXC (used in ShaderCompilation.cmake)
@@ -167,7 +167,7 @@ target_include_directories(NRDSample PRIVATE "External/NRIFramework/Include")
 target_include_directories(NRDSample PRIVATE "External/NRIFramework/External/NRI/Include")
 target_include_directories(NRDSample PRIVATE "External/NRIFramework/External")
 target_include_directories(NRDSample PRIVATE "External/NRD/Include" "External/NRD/Integration")
-target_compile_definitions(NRDSample PRIVATE ${PLATFORM_DEFINITIONS} PROJECT_NAME=NRDSample NRD_USE_OCT_NORMAL_ENCODING=${NRD_USE_OCT_NORMAL_ENCODING})
+target_compile_definitions(NRDSample PRIVATE ${PLATFORM_DEFINITIONS} PROJECT_NAME=NRDSample NRD_NORMAL_ENCODING=${NRD_NORMAL_ENCODING} NRD_ROUGHNESS_ENCODING=${NRD_ROUGHNESS_ENCODING})
 
 if (NOT DISABLE_SHADER_COMPILATION)
     add_dependencies(NRDSample NRDSampleShaders)

External/NRD

@@ -140,7 +140,7 @@ macro(list_hlsl_shaders HLSL_FILES HEADER_FILES SHADER_FILES)
             add_custom_command(
                     OUTPUT ${OUTPUT_PATH_DXBC} ${OUTPUT_PATH_DXBC}.h
                     COMMAND ${FXC_PATH} /nologo ${ENTRY_POINT} /T ${FXC_PROFILE} /WX /O3
-                        /DCOMPILER_FXC=1 /DNRD_USE_OCT_NORMAL_ENCODING=${NRD_USE_OCT_NORMAL_ENCODING} /DNRD_USE_MATERIAL_ID=${NRD_USE_MATERIAL_ID}
+                        /DCOMPILER_FXC=1 /DNRD_NORMAL_ENCODING=${NRD_NORMAL_ENCODING} /DNRD_ROUGHNESS_ENCODING=${NRD_ROUGHNESS_ENCODING}
                         /I "${EXTERNAL_INCLUDE_PATH}" /I "${SHADER_INCLUDE_PATH}" /I "${MATHLIB_INCLUDE_PATH}" /I "Include"
                         ${FILE_NAME} /Vn g_${BYTECODE_ARRAY_NAME}_dxbc /Fh ${OUTPUT_PATH_DXBC}.h /Fo ${OUTPUT_PATH_DXBC}
                     MAIN_DEPENDENCY ${FILE_NAME}
@@ -156,7 +156,7 @@ macro(list_hlsl_shaders HLSL_FILES HEADER_FILES SHADER_FILES)
             add_custom_command(
                     OUTPUT ${OUTPUT_PATH_DXIL} ${OUTPUT_PATH_DXIL}.h
                     COMMAND ${DXC_PATH} ${ENTRY_POINT} -T ${DXC_PROFILE} -WX -O3 -enable-16bit-types
-                        -DCOMPILER_DXC=1 -DNRD_USE_OCT_NORMAL_ENCODING=${NRD_USE_OCT_NORMAL_ENCODING} -DNRD_USE_MATERIAL_ID=${NRD_USE_MATERIAL_ID}
+                        -DCOMPILER_DXC=1 -DNRD_NORMAL_ENCODING=${NRD_NORMAL_ENCODING} -DNRD_ROUGHNESS_ENCODING=${NRD_ROUGHNESS_ENCODING}
                         -I "${EXTERNAL_INCLUDE_PATH}" -I "${SHADER_INCLUDE_PATH}" -I "${MATHLIB_INCLUDE_PATH}" -I "Include"
                         ${FILE_NAME} -Vn g_${BYTECODE_ARRAY_NAME}_dxil -Fh ${OUTPUT_PATH_DXIL}.h -Fo ${OUTPUT_PATH_DXIL}
                     MAIN_DEPENDENCY ${FILE_NAME}
@@ -172,7 +172,7 @@ macro(list_hlsl_shaders HLSL_FILES HEADER_FILES SHADER_FILES)
             add_custom_command(
                     OUTPUT ${OUTPUT_PATH_SPIRV} ${OUTPUT_PATH_SPIRV}.h
                     COMMAND ${DXC_SPIRV_PATH} ${ENTRY_POINT} -T ${DXC_PROFILE} -WX -O3 -enable-16bit-types
-                        -DCOMPILER_DXC=1 -DVULKAN=1 -DNRD_USE_OCT_NORMAL_ENCODING=${NRD_USE_OCT_NORMAL_ENCODING} -DNRD_USE_MATERIAL_ID=${NRD_USE_MATERIAL_ID}
+                        -DCOMPILER_DXC=1 -DVULKAN=1 -DNRD_NORMAL_ENCODING=${NRD_NORMAL_ENCODING} -DNRD_ROUGHNESS_ENCODING=${NRD_ROUGHNESS_ENCODING}
                         -I "${EXTERNAL_INCLUDE_PATH}" -I "${SHADER_INCLUDE_PATH}" -I "${MATHLIB_INCLUDE_PATH}" -I "Include"
                         ${FILE_NAME} -spirv -Vn g_${BYTECODE_ARRAY_NAME}_spirv -Fh ${OUTPUT_PATH_SPIRV}.h -Fo ${OUTPUT_PATH_SPIRV} ${DXC_VK_SHIFTS}
                         -spirv -fspv-target-env=vulkan1.2 -fspv-extension=SPV_EXT_descriptor_indexing -fspv-extension=KHR

External/NRIFramework

@@ -45,7 +45,6 @@ void main( uint2 tilePos : SV_GroupId, uint2 pixelPos : SV_DispatchThreadId, uin
     mipAndCone = GetConeAngleFromRoughness( geometryProps.mip, 1.0 );
 
     float3 BRDF = GetAmbientBRDF( geometryProps, materialProps, true );
-    BRDF *= float( !geometryProps.IsSky() );
 
     // Accumulate bounces not handled by the main tracer
     float3 Lsum = 0.0;
@@ -70,7 +69,6 @@ void main( uint2 tilePos : SV_GroupId, uint2 pixelPos : SV_DispatchThreadId, uin
 
         // Update BRDF
         BRDF *= GetAmbientBRDF( geometryProps, materialProps, true );
-        BRDF *= float( !geometryProps.IsSky() );
     }
 
     Lsum /= STL::ImportanceSampling::Uniform::GetPDF( );

ShaderCompilation.cmake

@@ -16,13 +16,14 @@ NRI_RESOURCE( Texture2D<float>, gIn_Downsampled_ViewZ, t, 1, 1 );
 NRI_RESOURCE( Texture2D<float4>, gIn_Normal_Roughness, t, 2, 1 );
 NRI_RESOURCE( Texture2D<float4>, gIn_BaseColor_Metalness, t, 3, 1 );
 NRI_RESOURCE( Texture2D<float3>, gIn_DirectLighting, t, 4, 1 );
-NRI_RESOURCE( Texture2D<float3>, gIn_Ambient, t, 5, 1 );
-NRI_RESOURCE( Texture2D<float4>, gIn_Diff, t, 6, 1 );
-NRI_RESOURCE( Texture2D<float4>, gIn_Spec, t, 7, 1 );
+NRI_RESOURCE( Texture2D<float3>, gIn_TransparentLighting, t, 5, 1 );
+NRI_RESOURCE( Texture2D<float3>, gIn_Ambient, t, 6, 1 );
+NRI_RESOURCE( Texture2D<float4>, gIn_Diff, t, 7, 1 );
+NRI_RESOURCE( Texture2D<float4>, gIn_Spec, t, 8, 1 );
 
 #if( NRD_MODE == SH )
-    NRI_RESOURCE( Texture2D<float4>, gIn_DiffSh, t, 8, 1 );
-    NRI_RESOURCE( Texture2D<float4>, gIn_SpecSh, t, 9, 1 );
+    NRI_RESOURCE( Texture2D<float4>, gIn_DiffSh, t, 9, 1 );
+    NRI_RESOURCE( Texture2D<float4>, gIn_SpecSh, t, 10, 1 );
 #endif
 
 // Outputs
@@ -64,6 +65,14 @@ float2 GetUpsampleUv( float2 pixelUv, float zReal )
     return uv;
 }
 
+float3 AddTransparentLighting( float3 Lsum, float3 Ltransparent )
+{
+    float mask = dot( Ltransparent, 1.0 );
+    Lsum = mask == 0.0 ? Lsum : Ltransparent;
+
+    return Lsum;
+}
+
 [numthreads( 16, 16, 1)]
 void main( int2 pixelPos : SV_DispatchThreadId )
 {
@@ -76,6 +85,7 @@ void main( int2 pixelPos : SV_DispatchThreadId )
 
     // Early out - sky
     float3 Ldirect = gIn_DirectLighting[ pixelPos ];
+    float3 Ltransparent = gIn_TransparentLighting[ pixelPos ];
     float viewZ = gIn_ViewZ[ pixelPos ];
 
     float4 normalAndRoughness = NRD_FrontEnd_UnpackNormalAndRoughness( gIn_Normal_Roughness[ pixelPos ] );
@@ -89,7 +99,7 @@ void main( int2 pixelPos : SV_DispatchThreadId )
     {
         Ldirect *= float( gOnScreen == SHOW_FINAL );
 
-        gOut_Composed[ pixelPos ] = float4( Ldirect, z );
+        gOut_Composed[ pixelPos ] = float4( AddTransparentLighting( Ldirect, Ltransparent ), z );
         gOut_ComposedDiff[ pixelPos ] = float4( 0, 0, 0, z );
         gOut_ComposedSpec[ pixelPos ] = float4( 0, 0, 0, z );
 
@@ -189,6 +199,7 @@ void main( int2 pixelPos : SV_DispatchThreadId )
     Lspec += ambient * spec.w * Fenv * specAmbientAmount;
 
     float3 Lsum = Ldirect + Ldiff + Lspec;
+    Lsum = AddTransparentLighting( Lsum, Ltransparent );
 
     // Debug
     if( gOnScreen == SHOW_DENOISED_DIFFUSE )
@@ -214,6 +225,6 @@ void main( int2 pixelPos : SV_DispatchThreadId )
 
     // Output
     gOut_Composed[ pixelPos ] = float4( Lsum, z );
-    gOut_ComposedDiff[ pixelPos ] = float4( Ldiff, z );
+    gOut_ComposedDiff[ pixelPos ] = float4( Ldirect + Ldiff, z );
     gOut_ComposedSpec[ pixelPos ] = float4( Lspec, z );
 }

Shaders/AmbientRays.cs.hlsl

@@ -13,10 +13,9 @@ license agreement from NVIDIA CORPORATION is strictly prohibited.
 // Inputs
 NRI_RESOURCE( Texture2D<float3>, gIn_DirectEmission, t, 0, 1 );
 NRI_RESOURCE( Texture2D<float4>, gIn_Shadow, t, 1, 1 );
-NRI_RESOURCE( Texture2D<float4>, gIn_TransparentLayer, t, 2, 1 );
 
 // Outputs
-NRI_RESOURCE( RWTexture2D<float3>, gInOut_DirectLighting, u, 3, 1 );
+NRI_RESOURCE( RWTexture2D<float3>, gInOut_DirectLighting, u, 0, 1 );
 
 [numthreads( 16, 16, 1)]
 void main( int2 pixelPos : SV_DispatchThreadId )
@@ -40,10 +39,6 @@ void main( int2 pixelPos : SV_DispatchThreadId )
     else if( gOnScreen >= SHOW_MESH )
         Lsum = Ldirect;
 
-    // Transparent layer ( reference mode )
-    float4 transparentLayer = ( gTransparent && gReference ) ? gIn_TransparentLayer[ pixelPos ] : 0;
-    Lsum = Lsum * ( 1.0 - transparentLayer.w ) * ( transparentLayer.w != 0.0 ? GLASS_TINT : 1.0 ) + transparentLayer.xyz;
-
     // Output
     gInOut_DirectLighting[ pixelPos ] = Lsum;
 }

Shaders/Composition.cs.hlsl

@@ -44,11 +44,11 @@ NRI_RESOURCE( Texture2D<float4>, gIn_Textures[], t, 4, 2 );
 #define FLAG_EMISSION                       0x04
 #define FLAG_FORCED_EMISSION                0x08
 
-// Local flags
-#define FLAG_BACKFACE                       0x10
-#define FLAG_UNUSED1                        0x20
-#define FLAG_UNUSED2                        0x40
-#define FLAG_UNUSED3                        0x80
+// Local flags // TODO: all unused
+#define FLAG_UNUSED1                        0x10
+#define FLAG_UNUSED2                        0x20
+#define FLAG_UNUSED3                        0x40
+#define FLAG_UNUSED4                        0x80
 
 #define GEOMETRY_ALL                        ( FLAG_OPAQUE_OR_ALPHA_OPAQUE | FLAG_EMISSION | FLAG_FORCED_EMISSION | FLAG_TRANSPARENT )
 #define GEOMETRY_ONLY_EMISSIVE              ( FLAG_EMISSION | FLAG_FORCED_EMISSION )
@@ -75,7 +75,7 @@ float3 _GetXoffset( float3 X, float3 offsetDirection )
     return X;// + offsetDirection * ( 0.003 + length( X - gCameraOrigin ) * 0.0005 );
 }
 
-struct GeometryProps // TODO: half
+struct GeometryProps
 {
     float3 X;
     float3 rayDirection;
@@ -100,9 +100,6 @@ struct GeometryProps // TODO: half
     bool IsForcedEmission( )
     { return ( textureOffsetAndFlags & ( ( FLAG_FORCED_EMISSION ) << FLAG_FIRST_BIT ) ) != 0; }
 
-    bool IsBackFace( )
-    { return ( textureOffsetAndFlags & ( ( FLAG_BACKFACE ) << FLAG_FIRST_BIT ) ) != 0; }
-
     uint GetBaseTexture( )
     { return textureOffsetAndFlags & INSTANCE_ID_MASK; }
 
@@ -116,7 +113,7 @@ struct GeometryProps // TODO: half
     { return tmin == INF; }
 };
 
-struct MaterialProps // TODO: half
+struct MaterialProps
 {
     float3 Ldirect; // unshadowed
     float3 Lemi;
@@ -282,20 +279,43 @@ float3 GetAmbientBRDF( GeometryProps geometryProps, MaterialProps materialProps,
     float3 albedo, Rf0;
     STL::BRDF::ConvertBaseColorMetalnessToAlbedoRf0( materialProps.baseColor, materialProps.metalness, albedo, Rf0 );
 
-    float3 ambBRDF;
+    float3 Fenv = Rf0;
     if( !approximate )
     {
         float NoV = abs( dot( materialProps.N, -geometryProps.rayDirection ) );
-        float3 Fenv = STL::BRDF::EnvironmentTerm_Ross( Rf0, NoV, materialProps.roughness );
-
-        ambBRDF = albedo * ( 1.0 - Fenv ) + Fenv;
+        Fenv = STL::BRDF::EnvironmentTerm_Ross( Rf0, NoV, materialProps.roughness );
     }
-    else
-        ambBRDF = albedo * ( 1.0 - Rf0 ) + Rf0;
+
+    float3 ambBRDF = albedo * ( 1.0 - Fenv ) + Fenv;
+    ambBRDF *= float( !geometryProps.IsSky() );
 
     return ambBRDF;
 }
 
+float EstimateDiffuseProbability( GeometryProps geometryProps, MaterialProps materialProps, bool useMagicBoost = false )
+{
+    float3 albedo, Rf0;
+    STL::BRDF::ConvertBaseColorMetalnessToAlbedoRf0( materialProps.baseColor, materialProps.metalness, albedo, Rf0 );
+
+    float smc = GetSpecMagicCurve( materialProps.roughness );
+    float NoV = abs( dot( materialProps.N, -geometryProps.rayDirection ) );
+    float3 Fenv = STL::BRDF::EnvironmentTerm_Ross( Rf0, NoV, materialProps.roughness );
+
+    float lumSpec = STL::Color::Luminance( Fenv );
+    float lumDiff = STL::Color::Luminance( albedo * ( 1.0 - Fenv ) );
+
+    // Boost diffuse if roughness is high
+    if( useMagicBoost )
+    {
+        lumDiff = lerp( lumDiff, 1.0, smc );
+        lumSpec = lerp( lumSpec, 0.0, smc );
+    }
+
+    float diffProb = lumDiff / ( lumDiff + lumSpec + 1e-6 );
+
+    return diffProb;
+}
+
 //====================================================================================================================================
 // TRACER
 //====================================================================================================================================

Shaders/DirectLighting.cs.hlsl

@@ -134,7 +134,7 @@ NRI_RESOURCE( SamplerState, gLinearSampler, s, 2, 0 );
 NRI_RESOURCE( SamplerState, gNearestSampler, s, 3, 0 );
 
 //=============================================================================================
-// DENOISER PART
+// NRD
 //=============================================================================================
 
 #define NRD_HEADER_ONLY
@@ -149,7 +149,7 @@ NRI_RESOURCE( SamplerState, gNearestSampler, s, 3, 0 );
 #define USE_SIMPLEX_LIGHTING_MODEL          0
 #define USE_IMPORTANCE_SAMPLING             1
 #define USE_SANITIZATION                    0 // NRD sample is NAN/INF free
-#define USE_SIMULATED_MATERIAL_ID_TEST      0 // for NRD_USE_MATERIAL_ID support debugging
+#define USE_SIMULATED_MATERIAL_ID_TEST      0 // for "material ID" support debugging
 
 #define BRDF_ENERGY_THRESHOLD               0.003
 #define AMBIENT_FADE                        ( -0.001 * gUnitToMetersMultiplier * gUnitToMetersMultiplier )
@@ -159,7 +159,8 @@ NRI_RESOURCE( SamplerState, gNearestSampler, s, 3, 0 );
 #define TAA_MOTION_MAX_REUSE                0.1
 #define MAX_MIP_LEVEL                       11.0
 #define IMPORTANCE_SAMPLE_NUM               16
-#define GLASS_TINT                          float3( 0.9, 0.9, 1.0 )
+#define GLASS_THICKNESS                     0.003 // m
+#define GLASS_TINT                          float3( 0.95, 0.95, 0.99 )
 
 //=============================================================================================
 // CONSTANTS
@@ -218,36 +219,29 @@ float GetSpecMagicCurve( float roughness )
     return f;
 }
 
-float3 ApplyPostLightingComposition( uint2 pixelPos, float3 Lsum, Texture2D<float4> gIn_TransparentLayer, bool convertToLDR = true )
+// IMPORTANT: requires STL::Rng::Initialize
+float3 ApplyExposure( float3 Lsum, bool convertToLDR = true )
 {
-    // Transparent layer ( non-reference mode )
-    float4 transparentLayer = ( gTransparent && !gReference ) ? gIn_TransparentLayer[ pixelPos ] : 0;
-    Lsum = Lsum * ( 1.0 - transparentLayer.w ) * ( transparentLayer.w != 0.0 ? GLASS_TINT : 1.0 ) + transparentLayer.xyz;
-
     // Exposure
     if( gOnScreen <= SHOW_DENOISED_SPECULAR )
     {
         Lsum *= gExposure;
 
         // Dithering
-        // IMPORTANT: requires STL::Rng::Initialize
         float rnd = STL::Rng::GetFloat2( ).x;
         float luma = STL::Color::Luminance( Lsum );
         float amplitude = lerp( 0.4, 1.0 / 1024.0, STL::Math::Sqrt01( luma ) );
         float dither = 1.0 + ( rnd - 0.5 ) * amplitude;
         Lsum *= dither;
     }
 
-    if( convertToLDR )
-    {
-        // Tonemap
-        if( gOnScreen == SHOW_FINAL )
-            Lsum = STL::Color::HdrToLinear_Uncharted( Lsum );
+    // Tonemap
+    if( convertToLDR && gOnScreen == SHOW_FINAL )
+        Lsum = STL::Color::HdrToLinear_Uncharted( Lsum );
 
-        // Conversion
-        if( gOnScreen == SHOW_FINAL || gOnScreen == SHOW_BASE_COLOR )
-            Lsum = STL::Color::LinearToSrgb( Lsum );
-    }
+    // Conversion
+    if( convertToLDR && ( gOnScreen == SHOW_FINAL || gOnScreen == SHOW_BASE_COLOR ) )
+        Lsum = STL::Color::LinearToSrgb( Lsum );
 
     return Lsum;
 }