vtk-m2/vtkm/interop/TransferToOpenGL.h
2017-08-24 15:02:46 -04:00

133 lines
4.4 KiB
C++

//============================================================================
// 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 2014 Sandia Corporation.
// Copyright 2014 UT-Battelle, LLC.
// Copyright 2014 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_interop_TransferToOpenGL_h
#define vtk_m_interop_TransferToOpenGL_h
#include <vtkm/cont/ArrayHandle.h>
#include <vtkm/cont/DeviceAdapter.h>
#include <vtkm/cont/ErrorBadValue.h>
#include <vtkm/cont/TryExecute.h>
#include <vtkm/interop/BufferState.h>
#include <vtkm/interop/internal/TransferToOpenGL.h>
#include <vtkm/cont/cuda/DeviceAdapterCuda.h>
#include <vtkm/cont/serial/DeviceAdapterSerial.h>
#include <vtkm/cont/tbb/DeviceAdapterTBB.h>
namespace vtkm
{
namespace interop
{
namespace detail
{
template <typename ArrayT>
struct PrepareForInteropFunctor
{
ArrayT& Array;
PrepareForInteropFunctor(ArrayT& array)
: Array(array)
{
}
template <typename DeviceAdapterTag>
bool operator()(DeviceAdapterTag) const
{
using Traits = vtkm::cont::DeviceAdapterTraits<DeviceAdapterTag>;
this->Array.PrepareForInput(DeviceAdapterTag());
return this->Array.GetDeviceAdapterId() == Traits::GetId();
}
};
}
/// \brief Manages transferring an ArrayHandle to opengl .
///
/// \c TransferToOpenGL manages to transfer the contents of an ArrayHandle
/// to OpenGL as efficiently as possible. Will use the given \p state to determine
/// what buffer handle to use, and the type to bind the buffer handle too.
/// If the type of buffer hasn't been determined the transfer will use
/// deduceAndSetBufferType to do so. Lastly state also holds on to per backend resources
/// that allow for efficient updating to open gl
///
/// This function keeps the buffer as the active buffer of the input type.
///
/// This function will throw exceptions if the transfer wasn't possible
///
template <typename ValueType, class StorageTag, class DeviceAdapterTag>
VTKM_CONT void TransferToOpenGL(vtkm::cont::ArrayHandle<ValueType, StorageTag> handle,
BufferState& state,
DeviceAdapterTag)
{
vtkm::interop::internal::TransferToOpenGL<ValueType, DeviceAdapterTag> toGL(state);
return toGL.Transfer(handle);
}
/// Dispatch overload for TransferToOpenGL that deduces the DeviceAdapter for
/// the given ArrayHandle.
///
/// \overload
///
template <typename ValueType, class StorageTag>
VTKM_CONT void TransferToOpenGL(vtkm::cont::ArrayHandle<ValueType, StorageTag> handle,
BufferState& state)
{
vtkm::cont::DeviceAdapterId devId = handle.GetDeviceAdapterId();
if (devId == VTKM_DEVICE_ADAPTER_UNDEFINED)
{
using ArrayT = vtkm::cont::ArrayHandle<ValueType, StorageTag>;
using Functor = detail::PrepareForInteropFunctor<ArrayT>;
// Undefined device means that the array is not in an execution environment.
// In this case, call PrepareForInput using the devices in the tracker
// to move the data onto a device. This is required for a CUDA usecase
// where a device pointer is set as control memory to reuse an already
// allocated buffer. PrepareForInput on CUDA will detect this and set the
// execution pointer to match the control pointer.
vtkm::cont::TryExecute(Functor(handle));
devId = handle.GetDeviceAdapterId();
}
switch (devId)
{
case VTKM_DEVICE_ADAPTER_SERIAL:
TransferToOpenGL(handle, state, vtkm::cont::DeviceAdapterTagSerial());
break;
#ifdef VTKM_ENABLE_TBB
case VTKM_DEVICE_ADAPTER_TBB:
TransferToOpenGL(handle, state, vtkm::cont::DeviceAdapterTagTBB());
break;
#endif
#ifdef VTKM_CUDA
case VTKM_DEVICE_ADAPTER_CUDA:
TransferToOpenGL(handle, state, vtkm::cont::DeviceAdapterTagCuda());
break;
#endif
default:
throw vtkm::cont::ErrorBadValue("Unknown device id.");
}
}
}
}
#endif //vtk_m_interop_TransferToOpenGL_h