Commit f7e28107 authored by Robert Maynard's avatar Robert Maynard

Rewrite the VTK-m README document.

parent 49b11461
data/* filter=lfs diff=lfs merge=lfs -text
/**/data/* filter=lfs diff=lfs merge=lfs -text
*.cmake whitespace=tab-in-indent
*.md whitespace=tab-in-indent conflict-marker-size=79
*.rst whitespace=tab-in-indent conflict-marker-size=79
*.txt whitespace=tab-in-indent
## VTK-m ##
One of the biggest recent changes in high-performance computing is the increasing use of accelerators. Accelerators contain processing cores that independently are inferior to a core in a typical CPU, but these cores are replicated and grouped such that their aggregate execution provides a very high computation rate at a much lower power. Current and future CPU processors also require much more explicit parallelism. Each successive version of the hardware packs more cores into each processor, and technologies like hyperthreading and vector operations require even more parallel processing to leverage each core’s full potential.
VTK-m is a toolkit of scientific visualization algorithms for emerging processor architectures. VTK-msupports the fine-grained concurrency for data analysis and visualization algorithms required to drive extreme scale computing by providing abstract models for data and execution that can be applied to a variety of algorithms across many different processor architectures.
VTK-m is a toolkit of scientific visualization algorithms for emerging processor architectures. VTK-m supports the fine-grained concurrency for data analysis and visualization algorithms required to drive extreme scale computing by providing abstract models for data and execution that can be applied to a variety of algorithms across many different processor architectures.
You can find out more about the design of VTK-m on our [wiki][]
Dependencies
============
## Getting VTK-m ##
VTK-m Requires:
The VTK-m repository is located at [https://gitlab.kitware.com/vtk/vtk-m](https://gitlab.kitware.com/vtk/vtk-m)
+ C++11 Compiler. VTK-m has been confirmed to work with the following
+ GCC 4.8+
+ Clang 3.3+
+ XCode 5.0+
+ MSVC 2013+
+ [CMake 3.3](http://www.cmake.org/download/)
VTK-m required dependencies are:
+ [CMake 3.3](http://www.cmake.org/download/)
Optional dependencies are:
+ CUDA Device Adapter
+ [Cuda Toolkit 7+](https://developer.nvidia.com/cuda-toolkit)
+ TBB Device Adapter
+ [TBB](https://www.threadingbuildingblocks.org/)
+ Rendering Module
+ The rendering module requires that you have a extension binding library and one rendering library. A windowing library is not needed expect for some optional tests.
+ Extension Binding
+ [GLEW](http://glew.sourceforge.net/)
+ Rendering Canvas
+ OpenGL Driver (See your GPU/iGPU vendor)
+ EGL (See your GPU/iGPU vendor)
+ [OSMesa](https://www.mesa3d.org/osmesa.html)
+ Windowing/Contexts
+ EGL (See your GPU/iGPU vendor)
+ [GLFW](http://www.glfw.org/)
+ [GLUT](http://freeglut.sourceforge.net/)
VTK-m optional dependencies are:
+ [Cuda Toolkit 7+](https://developer.nvidia.com/cuda-toolkit)
+ [TBB](https://www.threadingbuildingblocks.org/)
Building
========
VTK-m supports all majors platforms ( Windows, Linux, OSX ), and uses CMake
to generate all the build rules for the project.
```
git clone https://gitlab.kitware.com/vtk/vtk-m.git vtkm
mkdir vtkm-build
cd vtkm-build
cmake-gui ../vtkm
$ git clone https://gitlab.kitware.com/vtk/vtk-m.git
$ mkdir vtkm-build
$ cd vtkm-build
$ cmake-gui ../vtk-m
$ make -j<N>
$ make test
```
A detailed walk-through of installing and building VTK-m can be found on our [Contributing page](http://m.vtk.org/index.php/Contributing_to_VTK-m)
The VTK-m CMake configuration supports several options, including what specific
device adapters ( e.g. CUDA, TBB ) that you wish to enable. Here are some
relevant options
| Variable | Description |
|-----------------------------|-----------------------------|
| BUILD_SHARED_LIBS | Enabled by default. Build all VTK-m libraries as shared libraries. |
| CMAKE_BUILD_TYPE | This statically specifies what build type (configuration) will be built in this build tree. Possible values are empty, Debug, Release, RelWithDebInfo and MinSizeRel. This variable is only meaningful to single-configuration generators (such as make and Ninja). |
| CMAKE_INSTALL_PREFIX | Directory to install VTK-m into. |
| VTKm_ENABLE_EXAMPLES | Disabled by default. Turn on building of simple examples of using VTK-m. |
| VTKm_ENABLE_BENCHMARKS | Disabled by default. Turn on additional timing tests. |
| VTKm_ENABLE_CUDA | Disabled by default. Enable CUDA backend. |
| VTKm_CUDA_Architecture | Defaults to native. Specify what GPU architecture(s) to build CUDA code for, options include native, fermi, kepler, maxwell, and pascal. |
| VTKm_ENABLE_TBB | Disabled by default. Enable Intel Threading Building Blocks backend. |
| VTKm_ENABLE_TESTING | Enabled by default. Turn on header, unit, worklet, and filter tests. |
| VTKm_ENABLE_RENDERING | Enabled by default. Turn on the rendering module. |
| VTKm_USE_64BIT_IDS | Enabled by default. This is the size of integers used to index arrays, points, cells, etc. Use 64 bit precision when on, 32 bit precision when off. |
| VTKm_USE_DOUBLE_PRECISION | Disabled by default. Precision to use in floating point numbers when no other precision can be inferred. Use 64 bit precision when on, 32 bit precision when off. |
Learning
========
VTK-m offers numerous different ways to learn how to use the provided components.
If you are interested in a high level overview of VTK-m a good place to start
is with the IEEE Vis talk ["VTK-m: Accelerating the Visualization Toolkit for Massively Threaded Architectures"](http://m.vtk.org/images/2/29/VTKmVis2016.pptx) or the older and more technical
presentation
["VTK-m Overview for Intel Design Review"](http://m.vtk.org/images/a/a4/VTKmIntelMeet.pptx).
If you are interested in learning how to use the existing VTK-m codebase,
or how to integrate into your own project, we recommend reading "Part 1: Getting Started"
and "Part 2: Using VTK-m" of the [VTK-m Users Guide][].
If you want to contribute to VTK-m we recommend reading the following sections
of the [VTK-m Users Guide][].
+ "Part 2: Using VTK-m"
- Covers the core fundamental components of VTK-m including data model, worklets, and filters.
- "Part 3: Developing with VTK-m"
- Covers how to develop new worklets and filters.
- "Part 4: Advanced Development"
- Covers topics such as new worklet tags, opengl interop and custom device adapters .
Example
=======
The VTK-m source distribution includes a number of examples. The goal of the VTK-m examples is to illustrate specific VTK-m concepts in a consistent and simple format. However, these examples only cover a small part of the capabilities of VTK-m.
Below is a simple example of using VTK-m to load a VTK image file, run the
Marching Cubes algorithm on it, and render the results to an image:
```cpp
vtkm::io::reader::VTKDataSetReader reader("path/to/vtk_image_file");
inputData = reader.ReadDataSet();
vtkm::Float64 isovalue = 100.0f;
std::string fieldName = "pointvar";
// Create an isosurface filter
vtkm::filter::MarchingCubes filter;
filter.SetIsoValue(0, isovalue);
vtkm::filter::ResultDataSet result = filter.Execute( inputData,
inputData.GetField(fieldName) );
filter.MapFieldOntoOutput(result, inputData.GetField(fieldName));
// compute the bounds and extends of the input data
vtkm::Bounds coordsBounds =
inputData.GetCoordinateSystem().GetBounds();
vtkm::Vec<vtkm::Float64,3> totalExtent( coordsBounds.X.Length(),
coordsBounds.Y.Length(),
coordsBounds.Z.Length() );
vtkm::Float64 mag = vtkm::Magnitude(totalExtent);
vtkm::Normalize(totalExtent);
// setup a camera and point it to towards the center of the input data
vtkm::rendering::Camera camera;
camera.ResetToBounds(coordsBounds);
camera.SetLookAt(totalExtent * (mag * .5f));
camera.SetViewUp(vtkm::make_Vec(0.f, 1.f, 0.f));
camera.SetClippingRange(1.f, 100.f);
camera.SetFieldOfView(60.f);
camera.SetPosition(totalExtent * (mag * 2.f));
vtkm::rendering::ColorTable colorTable("thermal");
// Create a mapper, canvas and view that will be used to render the scene
vtkm::rendering::Scene scene;
vtkm::rendering::MapperRayTracer mapper;
vtkm::rendering::CanvasRayTracer canvas(512,512);
vtkm::rendering::Color bg(0.2f, 0.2f, 0.2f, 1.0f);
// Render an image of the output isosurface
vtkm::cont::DataSet& outputData = result.GetDataSet();
scene.AddActor(vtkm::rendering::Actor(outputData.GetCellSet(),
outputData.GetCoordinateSystem(),
outputData.GetField(fieldName),
colorTable));
vtkm::rendering::View3D view(scene, mapper, canvas, camera, bg);
view.Initialize();
view.Paint();
view.SaveAs("demo_output.pnm");
```
Contributing
============
There are many ways to contribute to [VTK-m][], with varying levels of effort.
+ Ask a question on the [VTK-m users email list](http://vtk.org/mailman/listinfo/vtkm)
+ Submit a feature request or bug, or add to an existing discussion on the VTK-m [Issue Tracker][]
+ Submit a Pull Request to improve [VTK-m]
++ See [CONTRIBUTING.md](CONTRIBUTING.md) for detailed instructions on how to create
a Pull Request.
++ Submit an Issue or Pull Request for the [VTK-m User's Guide](http://m.vtk.org/images/c/c8/VTKmUsersGuide.pdf)
License
=======
VTK-m is distributed under the OSI-approved BSD 3-clause License.
See [LICENSE.txt](LICENSE.txt) for details.
[VTK-m]: https://gitlab.kitware.com/vtk/vtk-m/
[Issue Tracker]: https://gitlab.kitware.com/vtk/vtk-m/issues
[wiki]: http://m.vtk.org/
[VTK-m Users Guide]: http://m.vtk.org/images/c/c8/VTKmUsersGuide.pdf
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment