ForDevelopers
Developers¶
The success of the VTK Examples depends on the contributions from the VTK user community. If you wish to contribute to this valuable resource, please follow these guidelines. If you are a VTK Example User, go here or an Example Administrator go here.
C++, C#, Python, and Java examples are welcome! Examples should illustrate a single concept.
Follow the Coding Guidelines¶
When you write an example, please follow the coding guidelines. Create the example in your local repository, compile and run it before you generate a pull request.
Some additional steps need to be done for Python C# and Java, see the sections below.
Setup for Development¶
This assumes you have VTK
, CMake
, git
and git lfs
installed.
Fork the repository¶
Go to the VTK Examples Repository, sign in/register, and then fork the repository.
A fork is a copy of a project. Forking a repository allows you to make changes without affecting the original project.
Clone the VTK examples repository onto your local machine and build it¶
If you are using SSH:
git clone git@gitlab.kitware.com:<username>/vtk-examples.git
If You are using HTTPS:
git clone https://gitlab.kitware.com/<username>/vtk-examples.git
Add the vtk-examples repository as a remote called upstream¶
cd vtk-examples
git remote add upstream https://gitlab.kitware.com/vtk/vtk-examples.git
Now build it¶
cd vtk-examples
cd build
cmake -DVTK_DIR:PATH=YOUR_VTK_BIN_DIR -DBUILD_TESTING:BOOL=ON ..
make
where YOUR_VTK_BIN_DIR is the location of your VTK build.
Before adding your examples¶
Sync your repository with the vtk-examples repository. Remember that to run the following commands, you need to be in the vtk-examples directory.
git fetch upstream
git switch master
git merge upstream/master
git push
- Build the vtk-examples code
cd vtk-examples
cd build
cmake -DVTK_DIR:PATH=YOUR_VTK_BIN_DIR -DBUILD_TESTING:BOOL=ON ..
make
where YOUR_VTK_BIN_DIR is the location of your VTK build.
Add the example¶
Create a branch in your repository
git checkout -b MyNewExample
where MyNewExample is the name of your new example.
Choose a Topic¶
The examples are organized by topic. Current topics include Animation, DataStructures, Filters, GeometricObjects, Images, Meshes, etc.
Write the source¶
-
The following snippets may be of use:
- Python available snippets.
-
Save your source code in vtk-examples/src/LANGUAGE/TOPIC/
Where LANGUAGE is Cxx, Python, CSharp or Java and TOPIC is the topic that you have chosen.
Steps for C++¶
- Build and test your example (NOTE: only for cxx examples)
cd vtk-examples/build
cmake ..
make
ctest -V -R MyNewExample
Note: If MyNewExample is not built, then in the directory where you put the file, do:
touch CMakeLists.txt
-
If your C++ example does any rendering, the test will fail the first time and create an image in vtk-examples/build/Testing/Temporary. The image will be called TestMyNewExample.png.
-
Copy the image into: vtk-examples/src/Testing/Baseline/LANG/TOPIC/. For Python and other languages, create an image with the proper name using a screen capture and copy that image into the proper location.
-
Rerun ctest and the test should pass.
At this point you are ready to push the changes to GitLab.
Steps for Python, Java and C¶
- TODO: Add in new instructions for Python.
If you are basing your code on a Cxx example use the same name as the Cxx example. This ensures that automatic cross-referencing works.
Keep the same directory structure as that in Cxx.
- Follow first three steps above.
- Manually create a test image if your example does any rendering. The image should be called TestMyNewExample.png.
The following snippets can be used to write the image out:
- WriteImage for Python
- WriteImage for Java
Add the example to the language page¶
Depending on the language of your example, edit the file Cxx.md, Python.md, CSharp.md, or Java.md.
Find the section for your topic and add a line for your new example. The format of the line is:
[MyNewExample]/**LANG**/**TOPIC**/**MyNewExample** | doxygen | short description
where LANG is one of Cxx, Python, CSharp, Java.
Commit your changes to your topic branch¶
git add MyNewExample.cxx
and if you have a baseline image,
git add Testing/Baseline/LANG/TOPIC/TestMyNewExample.png
finally,
git commit
Push the changes to GitLab¶
git push origin MyNewExample
Go to your GitLab project¶
Then generate a merge request for review.
See here for how to generate a merge request.
Advanced usage¶
Add a description¶
If your example could benefit from an extended description, you can create a file MyNewExample.md. Store the file alongside your source code. Use markdown to format the description. Also look at existing files for layout ideas.
Add arguments to the test¶
If your example requires arguments, you will need to edit the CMakeLists.txt in the topic directory.
-
Add the name of your example to the NEEDS_ARGS variable
-
Add an ADD_TEST line. See other CMakeLists.txt files for examples.
Add extra files to a C++ example¶
Most C++ examples consist of one file. If other files are required, place them in the same directory as the example. Then add a file with the same prefix as the example name and a .extras suffix. List each extra filename in the .extras file, one filename per line.
Warning
If you add extra files to the example, but do not add their filenames to the .extras file, they will appear in the left-hand file menus and will not be included in the tar file for the example.