adding VTK file exporter and test cases
This adds a legacy VTK file exporter which supports unstructured, explicit, and point meshes. (Single Cell Type cell sets are also supported.)
See merge request !247
The CellSet classes all exclusively work in the control environment.
However, CUDA likes to add __device__ to constructors, destructors, and
assignment operators it automatically adds. This in turn causes warnings
about the __device__ function using host-only classes (like
boost::shared_ptr). Solve this problem by adding explicit methods for
all of these.
We have been using the term "shape" in the cell set and connectivity
classes. To be consistent, use the term "shape" for the geometric
identify of the cell everywhere.
Most of VTK-m follows the convention of calling the 0D topology elements
"points" (which follows the convention of VTK). However, there were
several places where they were referred to as "nodes." Make things
consistent by calling them points everywhere.
Also merged some redundant ExecutionSignature tags.
Previously there was a Connectivity* structure for both the control
environment and the execution environment. This was necessary before
because the connectivity is explicit to the from and to topology
elements, so you would get this structure from the appropriate call to
CellSet*. However, the symantics are changed so that the type of
connectivity is selected in the worklet's dispatcher. Thus, it is now
much cleaner to manage the CellSet structure in the CellSet class itself
and just have a single set of Connectivity* classes in the execution
environment.
Also moved from vtkm namespace to vtkm::internal namespace. This change
is to then move the structured connectivity classes to the cont and exec
namespaces.
Previously, the items used to identify parts of topology like points,
cells, faces, etc. were in an enumeration. However, they are only really
used in template specialization, and it is easier to use tags in this
case. So, change the enumeration to a set of tag structures. Also made
the following changes:
* Renamed TopologyType to TopologyElement, which is more indicative of
what we are referring to.
* Moved the structures from the vtkm::cont namespace to the vtkm
namespace. There is no reason not to be able to use them from either the
control or execution environments.
* Added a VTKM_IS_TOPOLOGY_ELEMENT_TAG macro to do type checks on
template arguments that are supposed to be topology element tags.
The Invoke of the topology dispatcher is also changed to expect a
concrete cell set (which the DynamicCellSet is automatically cast to)
rather than a connectivity structure. The dispatcher calls the
GetNodeToCellConnectivity method for you. (That is currently the only
one supported.)
The DynamicCellSet will be used in place of the pointer to a CellSet
in a DataSet. This will prevent us from having to cast it all the time
and also remove reliance on boost smart_ptr.
The most common changes were making class members uppercase and spelled
out, adding "this->" whenever a class member is used, and declare
functions and members with export macros. Also fixed some uses of int
(instead of vtkm::Id or something similar) and a bit of indentation. I
also sprinkled some const goodness over the code.
It should be noted that I had about a week delay between first making
these changes and checking them in. In the mean time Sujin also made
some similar changes, so there might be some repetative changes.