Added VecFromPortal class.

vtkm/VecTraits.h

@@ -113,12 +113,12 @@ struct VecTraits
                                                 vtkm::IdComponent component,
                                                 ComponentType value);
 
-  /// Copies the components in this vector into a given Vec object.
+  /// Copies the components in the given vector into a given Vec object.
   ///
   template<vktm::IdComponent destSize>
   VTKM_EXEC_CONT_EXPORT
   static void
-  ToVec(const VecType &src, vtkm::Vec<ComponentType,destSize> &dest);
+  CopyInto(const VecType &src, vtkm::Vec<ComponentType,destSize> &dest);
 };
 #else // VTKM_DOXYGEN_ONLY
     ;

vtkm/exec/internal/CMakeLists.txt

@@ -20,6 +20,7 @@
 
 set(headers
   ErrorMessageBuffer.h
+  VecFromPortal.h
   WorkletInvokeFunctor.h
   WorkletInvokeFunctorDetail.h
   )

vtkm/exec/internal/VecFromPortal.h

@@ -0,0 +1,138 @@
+//============================================================================
+//  Copyright (c) Kitware, Inc.
+//  All rights reserved.
+//  See LICENSE.txt for details.
+//  This software is distributed WITHOUT ANY WARRANTY; without even
+//  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+//  PURPOSE.  See the above copyright notice for more information.
+//
+//  Copyright 2015 Sandia Corporation.
+//  Copyright 2015 UT-Battelle, LLC.
+//  Copyright 2015 Los Alamos National Security.
+//
+//  Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
+//  the U.S. Government retains certain rights in this software.
+//
+//  Under the terms of Contract DE-AC52-06NA25396 with Los Alamos National
+//  Laboratory (LANL), the U.S. Government retains certain rights in
+//  this software.
+//============================================================================
+#ifndef vtk_m_exec_internal_VecFromPortal_h
+#define vtk_m_exec_internal_VecFromPortal_h
+
+#include <vtkm/Math.h>
+#include <vtkm/Types.h>
+#include <vtkm/TypeTraits.h>
+#include <vtkm/VecTraits.h>
+
+namespace vtkm {
+namespace exec {
+namespace internal {
+
+/// \brief A short variable-length array from a window in an ArrayPortal.
+///
+/// The \c VecFromPortal class is a Vec-like class that holds an array portal
+/// and exposes a small window of that portal as if it were a \c Vec.
+///
+template<typename PortalType>
+class VecFromPortal
+{
+public:
+  typedef typename PortalType::ValueType ComponentType;
+
+  VTKM_EXEC_EXPORT
+  VecFromPortal() : NumComponents(0), Offset(0) {  }
+
+  VTKM_EXEC_EXPORT
+  VecFromPortal(const PortalType &portal,
+                vtkm::IdComponent numComponents = 0,
+                vtkm::Id offset = 0)
+    : Portal(portal), NumComponents(numComponents), Offset(offset) {  }
+
+  VTKM_EXEC_EXPORT
+  vtkm::IdComponent GetNumberOfComponents() const {
+    return this->NumComponents;
+  }
+
+  template<vtkm::IdComponent DestSize>
+  VTKM_EXEC_CONT_EXPORT
+  void CopyInto(vtkm::Vec<ComponentType,DestSize> &dest) const
+  {
+    vtkm::IdComponent numComponents = vtkm::Min(DestSize, this->NumComponents);
+    for (vtkm::IdComponent index = 0; index < numComponents; index++)
+    {
+      dest[index] = this->Portal.Get(index + this->Offset);
+    }
+  }
+
+  VTKM_EXEC_EXPORT
+  ComponentType operator[](vtkm::IdComponent index) const
+  {
+    return this->Portal.Get(index + this->Offset);
+  }
+
+private:
+  PortalType Portal;
+  vtkm::IdComponent NumComponents;
+  vtkm::Id Offset;
+};
+
+}
+}
+} // namespace vtkm::exec::internal
+
+// Implementations of traits classes, which by definition are in the vtkm
+// namespace.
+
+namespace vtkm {
+
+template<typename PortalType>
+struct TypeTraits<vtkm::exec::internal::VecFromPortal<PortalType> >
+{
+private:
+  typedef typename PortalType::ValueType ComponentType;
+
+public:
+  typedef typename vtkm::TypeTraits<ComponentType>::NumericTag NumericTag;
+  typedef TypeTraitsVectorTag DimensionalityTag;
+
+  VTKM_EXEC_EXPORT
+  static vtkm::exec::internal::VecFromPortal<PortalType> ZeroInitialization()
+  {
+    return vtkm::exec::internal::VecFromPortal<PortalType>();
+  }
+};
+
+template<typename PortalType>
+struct VecTraits<vtkm::exec::internal::VecFromPortal<PortalType> >
+{
+  typedef vtkm::exec::internal::VecFromPortal<PortalType> VecType;
+
+  typedef typename VecType::ComponentType ComponentType;
+  typedef vtkm::VecTraitsTagMultipleComponents HasMultipleComponents;
+  typedef vtkm::VecTraitsTagSizeVariable IsSizeStatic;
+
+  VTKM_EXEC_EXPORT
+  static vtkm::IdComponent GetNumberOfComponents(const VecType &vector) {
+    return vector.GetNumberOfComponents();
+  }
+
+  VTKM_EXEC_EXPORT
+  static ComponentType GetComponent(const VecType &vector,
+                                    vtkm::IdComponent componentIndex)
+  {
+    return vector[componentIndex];
+  }
+
+  template<vtkm::IdComponent destSize>
+  VTKM_EXEC_EXPORT
+  static void CopyInto(const VecType &src,
+                       vtkm::Vec<ComponentType,destSize> &dest)
+  {
+    src.CopyInto(dest);
+  }
+};
+
+} // namespace vtkm
+
+#endif //vtk_m_exec_internal_VecFromPortal_h

vtkm/exec/internal/testing/CMakeLists.txt

@@ -22,6 +22,7 @@
 
 set(unit_tests
   UnitTestErrorMessageBuffer.cxx
+  UnitTestVecFromPortal.cxx
   UnitTestWorkletInvokeFunctor.cxx
   )
 vtkm_unit_tests(SOURCES ${unit_tests})

vtkm/exec/internal/testing/UnitTestVecFromPortal.cxx

@@ -0,0 +1,119 @@
+//============================================================================
+//  Copyright (c) Kitware, Inc.
+//  All rights reserved.
+//  See LICENSE.txt for details.
+//  This software is distributed WITHOUT ANY WARRANTY; without even
+//  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+//  PURPOSE.  See the above copyright notice for more information.
+//
+//  Copyright 2015 Sandia Corporation.
+//  Copyright 2015 UT-Battelle, LLC.
+//  Copyright 2015 Los Alamos National Security.
+//
+//  Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
+//  the U.S. Government retains certain rights in this software.
+//
+//  Under the terms of Contract DE-AC52-06NA25396 with Los Alamos National
+//  Laboratory (LANL), the U.S. Government retains certain rights in
+//  this software.
+//============================================================================
+
+#include <vtkm/exec/internal/VecFromPortal.h>
+
+#include <vtkm/testing/Testing.h>
+
+namespace {
+
+static const vtkm::IdComponent ARRAY_SIZE = 10;
+
+template<typename T>
+void CheckType(T, T)
+{
+  // Check passes if this function is called correctly.
+}
+
+template<typename T>
+class TestPortal
+{
+public:
+  typedef T ValueType;
+
+  VTKM_EXEC_EXPORT
+  vtkm::Id GetNumberOfValues() const { return ARRAY_SIZE; }
+
+  VTKM_EXEC_EXPORT
+  ValueType Get(vtkm::Id index) const { return TestValue(index, ValueType()); }
+};
+
+struct VecFromPortalTestFunctor
+{
+  template<typename T>
+  void operator()(T) const
+  {
+    typedef TestPortal<T> PortalType;
+    typedef vtkm::exec::internal::VecFromPortal<PortalType> VecType;
+    typedef vtkm::TypeTraits<VecType> TTraits;
+    typedef vtkm::VecTraits<VecType> VTraits;
+
+    std::cout << "Checking VecFromPortal traits" << std::endl;
+
+    // The statements will fail to compile if the traits is not working as
+    // expected.
+    CheckType(typename TTraits::DimensionalityTag(),
+              vtkm::TypeTraitsVectorTag());
+    CheckType(typename VTraits::ComponentType(), T());
+    CheckType(typename VTraits::HasMultipleComponents(),
+              vtkm::VecTraitsTagMultipleComponents());
+    CheckType(typename VTraits::IsSizeStatic(),
+              vtkm::VecTraitsTagSizeVariable());
+
+    std::cout << "Checking VecFromPortal contents" << std::endl;
+
+    PortalType portal;
+
+    for (vtkm::Id offset = 0; offset < ARRAY_SIZE; offset++)
+    {
+      for (vtkm::IdComponent length = 0; length < ARRAY_SIZE-offset; length++)
+      {
+        VecType vec(portal, length, offset);
+
+        VTKM_TEST_ASSERT(vec.GetNumberOfComponents() == length,
+                         "Wrong length.");
+        VTKM_TEST_ASSERT(VTraits::GetNumberOfComponents(vec) == length,
+                         "Wrong length.");
+
+        vtkm::Vec<T,ARRAY_SIZE> copyDirect;
+        vec.CopyInto(copyDirect);
+
+        vtkm::Vec<T,ARRAY_SIZE> copyTraits;
+        VTraits::CopyInto(vec, copyTraits);
+
+        for (vtkm::IdComponent index = 0; index < length; index++)
+        {
+          T expected = TestValue(index+offset, T());
+          VTKM_TEST_ASSERT(test_equal(vec[index], expected), "Wrong value.");
+          VTKM_TEST_ASSERT(
+                test_equal(VTraits::GetComponent(vec, index), expected),
+                "Wrong value.");
+          VTKM_TEST_ASSERT(test_equal(copyDirect[index], expected),
+                           "Wrong copied value.");
+          VTKM_TEST_ASSERT(test_equal(copyTraits[index], expected),
+                           "Wrong copied value.");
+        }
+      }
+    }
+  }
+};
+
+void VecFromPortalTest()
+{
+  vtkm::testing::Testing::TryTypes(VecFromPortalTestFunctor(),
+                                   vtkm::TypeListTagCommon());
+}
+
+} // anonymous namespace
+
+int UnitTestVecFromPortal(int, char *[])
+{
+  return vtkm::testing::Testing::Run(VecFromPortalTest);
+}