Based on the work of Tyson Neuroth and Huu Tan Nguyen at the VTK-m code
sprint.
Shows how to invoke a simple worklet to generate coordinates and colors,
and than use opengl interop to display it to the screen.
By introducing our own custom thrust execution policy we can make sure
to hit the fastest code paths in thrust for the sort operation. This makes
sure that for UInt32,Int32, and Float32 we use the radix sort from thrust
which offers a 2x to 3x speed improvement over the merge sort implementation.
Secondly by telling thrust that our BinaryOperators are commutative we
make sure that we get the fastest code paths when executing Inclusive
and Exclusive Scan
Benchmark 'Radix Sort on 1048576 random values vtkm::Int32' results:
median = 0.0117049s
median abs dev = 0.00324614s
mean = 0.0167615s
std dev = 0.00786269s
min = 0.00845875s
max = 0.0389063s
Benchmark 'Radix Sort on 1048576 random values vtkm::Float32' results:
median = 0.0234463s
median abs dev = 0.000317249s
mean = 0.021452s
std dev = 0.00470307s
min = 0.011255s
max = 0.0250643s
Benchmark 'Merge Sort on 1048576 random values vtkm::Int32' results:
median = 0.0310486s
median abs dev = 0.000182129s
mean = 0.0286914s
std dev = 0.00634102s
min = 0.0116225s
max = 0.0317379s
Benchmark 'Merge Sort on 1048576 random values vtkm::Float32' results:
median = 0.0310617s
median abs dev = 0.000193583s
mean = 0.0295779s
std dev = 0.00491531s
min = 0.0147257s
max = 0.032307s
Optimize uniform coordinates
Add specializations when dealing with uniform coordinates on lines, quads (a.k.a. pixels), and hexahedra (a.k.a. voxels).
See merge request !172
Although this is labeled as a unit test, this is more of an integration
test to make sure that when a uniform point coordinate is passed as a
field to a WorkletTopologyMap from points to cells with a regular cell
set, you get the specialized VecRectilinearPointCoordinates in the
worklet argument.
In the special case where you are loading the point coordinates for a
structured grid in a point to cell map (an important use case), create a
VecRectilinearPointCoordinates rather than build a Vec of the values.
This will activate the cell specalizations in previous commits.
These changes also added some flat-to-logical index conversion and vice
versa in ConnectivityStructuredInternals. This change also fixed a bug
in getting cells attached to points in 2D grids. (Actually, technically
someone else fixed it and checked it in first. The changes were merged
during a rebase.)
I also added a specalization to Vec for 1D that implicitly converts
between the 1D Vec and the component. This can be convenient when
templating on the Vec length.
This class implicitly stores the point coordinates for a rectilinear
cell (such as a voxel) with just the location of the lower left point
and the spacing in each dimension. In addition to saving space, this
class should allow cell-specific functions to specialize for faster
processing.
493ca4e0 Merging with master
a10d1fc2 Removing unnecessary cell fields from isosurface test and example, and adding a few comments
70c49b14 Changing translation for isosurface example
a96da4e0 Moving viewpoint for IsosurfaceUniformGrid example
30100e2a Adding examples directory with isosurface rendering example
Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !163
adding cell-to-point topology support and worklet
This adds code to support a cell-to-point topological mapping worklet.
For explicit cell set, there is code to calculate a cell-to-point topology from the canonical point-to-cell topology. (It is not parallelized at this point.) Most of the required code for structured grids was already in place.
See merge request !154
