pyvk : Python Vulkan examples and demos

pyvk is a Python port of the wonderful framework from Sascha Willems vulkan examples. It has been started as a mean for me to discover Vulkan. The initial objectives were:

• use some of the proposed classes to ease development (but some classes require stuff not ported to python (gli?))
• part of these classes are in a vks namespace, thus make a vks python module
• port the main class (VulkanExampleBase) to Python
• try to implement triangle and scenerendering

Current status

Essential classes have been ported to Python in a vks Pyhton module, and the triangle, texture and scenerendering examples are running. Moreover imgui integration is also effective (included in the triangle demo). However not every methods have yet been rewritten in those classes. For instance there is no benchmarking facilities.

Only the XCB platform binding has been made, so this only runs on linux. It has been tested under Fedora 30 and Ubuntu 18.04, using both IGP Intel drivers and nvidia proprietary drivers.

The Windows platform binding is in development. If you use thonny for editing/running (I do), please note that the 32-bit Vulkan libraries are not tested. I had a pointer issue when using the 32bit default thonny interpreter (GetPhysicalDeviceSurfaceSupportKHR). Install a 64bit Python interpreter and point to it in thonny. Be aware to uninstall and reinstall every packages from thonny manager.

FPS comparisons with the C++ original examples

These are Frames Per Second values computed in the program itself. They are read directly from the screenshots. All FPS values here are stable during one execution, but there are some differences between executions (GPU Temp?). Min/Max frame times may also be added.

Example	CPU-Card-Driver-platform-os	C++	Python
triangle	i3 3220T-IGP-Intel Ivybridge-XCB-linux	798	757
triangle (imgui)	i3 3220T-IGP-Intel Ivybridge-XCB-linux	637	427
triangle	Pentium G4400-GTX950-nvidia proprietary-XCB-linux	4794	4279
triangle (imgui)	Pentium G4400-GTX950-nvidia proprietary-XCB-linux	4712	2561
texture	Pentium G4400-GTX950-nvidia proprietary-XCB-linux	3400	2800
scenerendering	Pentium G4400-GTX950-nvidia proprietary-XCB-linux	1800	1330

Note: All C++ examples were run without validation enabled, whereas Python examples were run with validation enabled.

Running the example(s)

First install the requirements (see below). At the moment I also use numpy as a mean to access C arrays from Python, thus you should also install it (pip3 install --user numpy).

Simply clone the repository in a directory of your choice and change directory

git clone https://github.com/geehalel/pyvk.git
cd pyvk

then run the desired demo

python3 triangle.py

Installation requirements

• install python vulkan binding

pip3 install vulkan --user

• install python xcb binding

pip3 install xcffib --user

• install python glm binding

pip3 install pyglm --user  

• install python imgui binding

pip3 install imgui --user

• install python wayland binding (not useful for now)

pip3 install pywayland --user

3D Model loading

Install the assimp python port from your distribution (python3-pyassimp) or from Pypi.

apt-get install python3-pyassimp

Textures loading

The tutorials mainly use the Khronos groupe ktx format for storing textures, but this format is not installed on Linux (no packages on Ubuntu and Fedora). The python vks module here includes a simple class in ktxfile.py to load such textures. Here are some links about this format:

• KTX File format specification
• The Khronos Group Library and Tools which contains source code for libktx library
• OpenGL Image (gli) library, C++ header only, used in the tutorials

There are otherwise numerous image libraries in Python, none of them reading ktx files, but some of them reading dds files (Microsoft texture file format).

• Pillow, the Python Image Library
• OpenImageIO which supports image formats used in VFX (visual effects for films/TV) and embeds an ImageCache framework. Supports Python directly. On Ubuntu the Python support is only packaged for Python 2.7 (python-openimageio). For Python 3, a package may be manually installed:

wget https://github.com/fredrikaverpil/oiio-python/releases/download/2.0.5%2B20190203/oiio-2.0.5-cp36-none-linux_x86_64.whl
pip3 install --user oiio-2.0.5-cp36-none-linux_x86_64.whl

Check your Python version, there is also a wheel for Python 3.7.

Screenshots

These are comparative screenshots of the original examples written in C++ and the ones here written in Python.

• Core i3-3220T, IGP, Intel Ivybridge, XCB, linux

Example	C++	Python
triangle
triangle (imgui)

• Pentium G4400, GTX950, nvidia proprietary, XCB, linux

Example	C++	Python
triangle
triangle (imgui)
texture
scenerendering