0028114: Visualization, Path tracing - Make path tracing mode interactive in high...

diff --git a/src/OpenGl/OpenGl_View.hxx b/src/OpenGl/OpenGl_View.hxx
index 5d79813..ba07b70 100644 (file)
--- a/src/OpenGl/OpenGl_View.hxx
+++ b/src/OpenGl/OpenGl_View.hxx
@@ -573,7 +573,7 @@ protected: //! @name data types related to ray-tracing
     OpenGl_RT_uWinSizeY,
 
     // sampled frame params
-    OpenGl_RT_uSampleWeight,
+    OpenGl_RT_uAccumSamples,
     OpenGl_RT_uFrameRndSeed,
 
     // adaptive FSAA params

diff --git a/src/OpenGl/OpenGl_View_Raytrace.cxx b/src/OpenGl/OpenGl_View_Raytrace.cxx
index 0b7a463..062e558 100644 (file)
--- a/src/OpenGl/OpenGl_View_Raytrace.cxx
+++ b/src/OpenGl/OpenGl_View_Raytrace.cxx
@@ -1721,8 +1721,8 @@ Standard_Boolean OpenGl_View::initRaytraceResources (const Handle(OpenGl_Context
       myUniformLocations[anIndex][OpenGl_RT_uWinSizeY] =
         aShaderProgram->GetUniformLocation (theGlContext, "uWinSizeY");
 
-      myUniformLocations[anIndex][OpenGl_RT_uSampleWeight] =
-        aShaderProgram->GetUniformLocation (theGlContext, "uSampleWeight");
+      myUniformLocations[anIndex][OpenGl_RT_uAccumSamples] =
+        aShaderProgram->GetUniformLocation (theGlContext, "uAccumSamples");
       myUniformLocations[anIndex][OpenGl_RT_uFrameRndSeed] =
         aShaderProgram->GetUniformLocation (theGlContext, "uFrameRndSeed");
 
@@ -2778,10 +2778,10 @@ Standard_Boolean OpenGl_View::runPathtrace (const Graphic3d_Camera::Projection
 
     // We upload tile offset texture each 4 frames in order
     // to minimize overhead of additional memory bandwidth.
-    // Adaptive sampling is starting after first 10 frames.
+    // Adaptive sampling is starting after first 30 frames.
     if (myAccumFrames % 4 == 0)
     {
-      myTileSampler.Upload (theGlContext, myRaytraceTileOffsetsTexture, myAccumFrames > 10);
+      myTileSampler.Upload (theGlContext, myRaytraceTileOffsetsTexture, myAccumFrames > 30);
     }
   }
 
@@ -2828,7 +2828,7 @@ Standard_Boolean OpenGl_View::runPathtrace (const Graphic3d_Camera::Projection
 
   // Set frame accumulation weight
   myRaytraceProgram->SetUniform (theGlContext,
-    myUniformLocations[0][OpenGl_RT_uSampleWeight], 1.f / (myAccumFrames + 1));
+    myUniformLocations[0][OpenGl_RT_uAccumSamples], myAccumFrames);
 
   // Set random number generator seed
   myRaytraceProgram->SetUniform (theGlContext,

diff --git a/src/Shaders/PathtraceBase.fs b/src/Shaders/PathtraceBase.fs
index 68bdad9..98400cc 100644 (file)
--- a/src/Shaders/PathtraceBase.fs
+++ b/src/Shaders/PathtraceBase.fs
@@ -12,6 +12,9 @@
 
 #ifdef PATH_TRACING
 
+//! Number of previously rendered frames.
+uniform int uAccumSamples;
+
 ///////////////////////////////////////////////////////////////////////////////////////
 // Specific data types
 
@@ -677,6 +680,9 @@ vec3 IntersectLight (in SRay theRay, in int theDepth, in float theHitDistance, o
 // Enables expiremental russian roulette sampling
 #define RUSSIAN_ROULETTE
 
+//! Frame step to increase number of bounces
+#define FRAME_STEP 5
+
 //=======================================================================
 // function : PathTrace
 // purpose  : Calculates radiance along the given ray
@@ -832,7 +838,7 @@ vec4 PathTrace (in SRay theRay, in vec3 theInverse)
     aSurvive = aDepth < 3 ? 1.f : min (dot (LUMA, aThroughput), 0.95f);
 #endif
 
-    if (RandFloat() > aSurvive || all (lessThanEqual (aThroughput, MIN_THROUGHPUT)))
+    if (RandFloat() > aSurvive || all (lessThan (aThroughput, MIN_THROUGHPUT)) || aDepth >= uAccumSamples / FRAME_STEP + step (1.f / M_PI, aImpPDF))
     {
       aDepth = INVALID_BOUNCES; // terminate path
     }

diff --git a/src/Shaders/RaytraceRender.fs b/src/Shaders/RaytraceRender.fs
index 00263f3..009270e 100644 (file)
--- a/src/Shaders/RaytraceRender.fs
+++ b/src/Shaders/RaytraceRender.fs
@@ -9,10 +9,7 @@ uniform int uFrameRndSeed;
 uniform int uBlockedRngEnabled;
 
 #ifndef ADAPTIVE_SAMPLING
-  //! Weight of current frame related to accumulated samples.
-  uniform float uSampleWeight;
-
-  //! Input accumulated image.
+  //! Input image with previously accumulated samples.
   uniform sampler2D uAccumTexture;
 #endif
 
@@ -95,13 +92,13 @@ void main (void)
 
 #else
 
-  if (uSampleWeight >= 1.f)
+  if (uAccumSamples == 0)
   {
     OutColor = aColor;
   }
   else
   {
-    OutColor = mix (texture2D (uAccumTexture, vPixel), aColor, uSampleWeight);
+    OutColor = mix (texture2D (uAccumTexture, vPixel), aColor, 1.f / (uAccumSamples + 1));
   }
 
 #endif // ADAPTIVE_SAMPLING

diff --git a/src/Shaders/Shaders_PathtraceBase_fs.pxx b/src/Shaders/Shaders_PathtraceBase_fs.pxx
index 1bb6832..527a49e 100644 (file)
--- a/src/Shaders/Shaders_PathtraceBase_fs.pxx
+++ b/src/Shaders/Shaders_PathtraceBase_fs.pxx
@@ -15,6 +15,9 @@ static const char Shaders_PathtraceBase_fs[] =
   "\n"
   "#ifdef PATH_TRACING\n"
   "\n"
+  "//! Number of previously rendered frames.\n"
+  "uniform int uAccumSamples;\n"
+  "\n"
   "///////////////////////////////////////////////////////////////////////////////////////\n"
   "// Specific data types\n"
   "\n"
@@ -680,6 +683,9 @@ static const char Shaders_PathtraceBase_fs[] =
   "// Enables expiremental russian roulette sampling\n"
   "#define RUSSIAN_ROULETTE\n"
   "\n"
+  "//! Frame step to increase number of bounces\n"
+  "#define FRAME_STEP 5\n"
+  "\n"
   "//=======================================================================\n"
   "// function : PathTrace\n"
   "// purpose  : Calculates radiance along the given ray\n"
@@ -835,7 +841,7 @@ static const char Shaders_PathtraceBase_fs[] =
   "    aSurvive = aDepth < 3 ? 1.f : min (dot (LUMA, aThroughput), 0.95f);\n"
   "#endif\n"
   "\n"
-  "    if (RandFloat() > aSurvive || all (lessThanEqual (aThroughput, MIN_THROUGHPUT)))\n"
+  "    if (RandFloat() > aSurvive || all (lessThan (aThroughput, MIN_THROUGHPUT)) || aDepth >= uAccumSamples / FRAME_STEP + step (1.f / M_PI, aImpPDF))\n"
   "    {\n"
   "      aDepth = INVALID_BOUNCES; // terminate path\n"
   "    }\n"

diff --git a/src/Shaders/Shaders_RaytraceRender_fs.pxx b/src/Shaders/Shaders_RaytraceRender_fs.pxx
index a3a04e0..e32c754 100644 (file)
--- a/src/Shaders/Shaders_RaytraceRender_fs.pxx
+++ b/src/Shaders/Shaders_RaytraceRender_fs.pxx
@@ -12,10 +12,7 @@ static const char Shaders_RaytraceRender_fs[] =
   "uniform int uBlockedRngEnabled;\n"
   "\n"
   "#ifndef ADAPTIVE_SAMPLING\n"
-  "  //! Weight of current frame related to accumulated samples.\n"
-  "  uniform float uSampleWeight;\n"
-  "\n"
-  "  //! Input accumulated image.\n"
+  "  //! Input image with previously accumulated samples.\n"
   "  uniform sampler2D uAccumTexture;\n"
   "#endif\n"
   "\n"
@@ -98,13 +95,13 @@ static const char Shaders_RaytraceRender_fs[] =
   "\n"
   "#else\n"
   "\n"
-  "  if (uSampleWeight >= 1.f)\n"
+  "  if (uAccumSamples == 0)\n"
   "  {\n"
   "    OutColor = aColor;\n"
   "  }\n"
   "  else\n"
   "  {\n"
-  "    OutColor = mix (texture2D (uAccumTexture, vPixel), aColor, uSampleWeight);\n"
+  "    OutColor = mix (texture2D (uAccumTexture, vPixel), aColor, 1.f / (uAccumSamples + 1));\n"
   "  }\n"
   "\n"
   "#endif // ADAPTIVE_SAMPLING\n"