Fix Sobol

Author: yozhijk

App/CL/camera.cl

@@ -43,7 +43,7 @@ __kernel void PerspectiveCamera_GeneratePaths(
                              uint rngseed,
                              // Output rays
                              __global ray* rays,
-                             __global uint const* random,
+                             __global uint* random,
                              __global uint const* sobolmat,
                              int frame
 #ifndef NO_PATH_DATA
@@ -68,6 +68,12 @@ __kernel void PerspectiveCamera_GeneratePaths(
         Sampler sampler;
 #if SAMPLER == SOBOL
         uint scramble = random[globalid.x + imgwidth * globalid.y] * 0x1fe3434f;
+
+        if (frame & 0xF)
+        {
+            random[globalid.x + imgwidth * globalid.y] = WangHash(scramble);
+        }
+
         Sampler_Init(&sampler, frame, SAMPLE_DIM_CAMERA_OFFSET, scramble);
 #elif SAMPLER == RANDOM
         uint scramble = globalid.x + imgwidth * globalid.y * rngseed;
@@ -152,6 +158,12 @@ __kernel void PerspectiveCameraDof_GeneratePaths(
         Sampler sampler;
 #if SAMPLER == SOBOL
         uint scramble = random[globalid.x + imgwidth * globalid.y] * 0x1fe3434f;
+
+        if (frame & 0xF)
+        {
+            random[globalid.x + imgwidth * globalid.y] = WangHash(scramble);
+        }
+
         Sampler_Init(&sampler, frame, SAMPLE_DIM_CAMERA_OFFSET, scramble);
 #elif SAMPLER == RANDOM
         uint scramble = globalid.x + imgwidth * globalid.y * rngseed;

App/CL/common.cl

@@ -36,7 +36,7 @@ THE SOFTWARE.
 #define SOBOL 2
 #define CMJ 3
 
-#define SAMPLER CMJ
+#define SAMPLER SOBOL
 
 #define CMJ_DIM 4
 

App/PT/ptrenderer.cpp

@@ -287,7 +287,7 @@ namespace Baikal
         std::vector<std::uint32_t> random_buffer(output.width() * output.height());
         std::generate(random_buffer.begin(), random_buffer.end(), std::rand);
 
-        m_render_data->random = m_context.CreateBuffer<std::uint32_t>(output.width() * output.height(), CL_MEM_READ_ONLY, &random_buffer[0]);
+        m_render_data->random = m_context.CreateBuffer<std::uint32_t>(output.width() * output.height(), CL_MEM_READ_WRITE, &random_buffer[0]);
         m_vidmemws += output.width() * output.height() * sizeof(std::uint32_t);
 
         std::vector<int> initdata(output.width() * output.height());