Merge pull request #2410 from savuor:fix/kinfu_fetch_checkzero

Fixed KinFu getCloud() at empty volume

* KinFu getCloud(): an empty volume check added to OCL code

* minor

modules/rgbd/src/tsdf.cpp

@@ -1393,7 +1393,7 @@ void TSDFVolumeGPU::fetchPointsNormals(OutputArray points, OutputArray normals)
                       (int)divUp(globalSize[2], (unsigned int)localSize[2]));
 
         const size_t counterSize = sizeof(int);
-        size_t lsz = localSize[0]*localSize[1]*localSize[2]*counterSize;
+        size_t lszscan = localSize[0]*localSize[1]*localSize[2]*counterSize;
 
         const int gsz[3] = {ngroups[2], ngroups[1], ngroups[0]};
         UMat groupedSum(3, gsz, CV_32S, Scalar(0));
@@ -1409,7 +1409,7 @@ void TSDFVolumeGPU::fetchPointsNormals(OutputArray points, OutputArray normals)
                    ocl::KernelArg::PtrReadOnly(volPoseGpu),
                    voxelSize,
                    voxelSizeInv,
-                   ocl::KernelArg::Local(lsz),
+                   ocl::KernelArg::Local(lszscan),
                    ocl::KernelArg::WriteOnlyNoSize(groupedSum));
 
         if(!kscan.run(3, globalSize, localSize, true))
@@ -1422,12 +1422,6 @@ void TSDFVolumeGPU::fetchPointsNormals(OutputArray points, OutputArray normals)
 
         // 2. fill output arrays according to per-group points count
 
-        ocl::Kernel kfill;
-        kfill.create("fillPtsNrm", source, options, &errorStr);
-
-        if(kfill.empty())
-            throw std::runtime_error("Failed to create kernel: " + errorStr);
-
         points.create(gpuSum, 1, POINT_TYPE);
         UMat pts = points.getUMat();
         UMat nrm;
@@ -1438,13 +1432,22 @@ void TSDFVolumeGPU::fetchPointsNormals(OutputArray points, OutputArray normals)
         }
         else
         {
-            // it won't access but empty args are forbidden
+            // it won't be accessed but empty args are forbidden
             nrm = UMat(1, 1, POINT_TYPE);
         }
+
+        if (gpuSum)
+        {
+            ocl::Kernel kfill;
+            kfill.create("fillPtsNrm", source, options, &errorStr);
+
+            if(kfill.empty())
+                throw std::runtime_error("Failed to create kernel: " + errorStr);
+
             UMat atomicCtr(1, 1, CV_32S, Scalar(0));
 
             // mem size to keep pts (and normals optionally) for all work-items in a group
-        lsz = localSize[0]*localSize[1]*localSize[2]*elemSize;
+            size_t lszfill = localSize[0]*localSize[1]*localSize[2]*elemSize;
 
             kfill.args(ocl::KernelArg::PtrReadOnly(volume),
                        volResGpu.val,
@@ -1454,7 +1457,7 @@ void TSDFVolumeGPU::fetchPointsNormals(OutputArray points, OutputArray normals)
                        voxelSize,
                        voxelSizeInv,
                        ((int)needNormals),
-                   ocl::KernelArg::Local(lsz),
+                       ocl::KernelArg::Local(lszfill),
                        ocl::KernelArg::PtrReadWrite(atomicCtr),
                        ocl::KernelArg::ReadOnlyNoSize(groupedSum),
                        ocl::KernelArg::WriteOnlyNoSize(pts),
@@ -1464,6 +1467,7 @@ void TSDFVolumeGPU::fetchPointsNormals(OutputArray points, OutputArray normals)
             if(!kfill.run(3, globalSize, localSize, true))
                 throw std::runtime_error("Failed to run kernel");
         }
+    }
 }
 
 #endif