README.md

A Python-based project on QML-VTK combination

The source code is based on Nicanor Romero Venier's project

Description

This project provides a solution to render VTK objects on QML-based UI.

Moreover, I re-organize the architecture of the code and make it simple and scalable.

The architecture can be described as below:

• MVVM architectural pattern is used. Model is put inside src/model folder. View is put inside src/view folder. ViewModel is put inside src/ctrls folder.
• Data/Variables which are cached/stored the app states should be saved in Model which is implemented Singleton design pattern.
• The Model will emit a Signal if data is changed.
• The ViewModel will catch that Signal and pass the data along with the Signal as the parameter.
• The ViewModel also exposes the methods to the View.
• ViewModel's methods will be called through the View.

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• Fbo and FboRenderer classes support graphical rendering process.
• src/graphics/vtkModel folder has VTK-related model which support the creation of VTK objects.
• ProcessingEngine class support VTK-related model managing.

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• Every graphical actions should be done inside Render Thread.
• Command pattern is used to make sure those actions will be done correctly.

Compatibility

The code was tested by using Anaconda3 and the following combinations:

• Python 3.6.6 + PySide2 5.13.2 + VTK 8.1.1/8.1.2/8.2.0 (built from source) + Ubuntu 16.04/Windows 10
• Python 3.7.5 + PySide2 5.13.1 + VTK 8.2 Thanks szmurlor
• Python 3.7.10 + PySide2 5.13.2/5.15.2 + VTK 8.1.2 (from pypi) Thanks Senthil

Installation

conda create --name QmlVtk python=3.7
conda activate QmlVtk

conda install -c conda-forge pyside2=5.13.2 # Linux
pip install PySide2==5.13.2 # Windows

pip install vtk==8.1.2 # check compatibility section

Troubleshoot

If you want to use vtkGPUVolumeRayCastMapper, you have to use vtkExternalOpenGLRenderWindow instead of vtkGenericOpenGLRenderWindow (in FboRenderer class). vtkExternalOpenGLRenderWindow will require VTK to be built with vtkRenderingExternal option. It means you have to rebuild VTK from source.

Example