Forked from janhsimon's openxr-vulkan-example, original Readme at the end

Overview

This project is an example of n-body particle rendering with a simple point pipeline rendering. It features:

• A shader computing a "realistic" mass / size ratio, with a radius proportional to the cube root of the mass.
• At the moment, a simple brute force n-body computation simulating gravity.
• Simulation of merging particles: to avoid simulation collapse when two particles are really close (which often cause both of them to be shoot out really fast), two close particles are merged

Merging mechanism

At the moment, the merging criteria is a fixed minimum distance between particles. A better approach would be to find a criteria which takes into account the mass, so that two heavy bodies or one heavy and one small body merge at a further distance than two small particles.

The implementation is not optimised and quite trivial: the heavier particle is given the sum of the mass and inertia of the two coming particles, and the smallest one is set a mass of zero, and then ignored in the rest of the simulation. This can become very sparse after a while, but it avoids changing some buffer and gpu buffer sizes, and the simulation still becomes a bit faster as null mass particles are skipped.

Precision about build

The repository already contains libs for windows: the external dependencies are thus not expected to be build. However, they seems to be given in release mode, so trying to create a Debug build could be problematic.

Original Readme

Overview

This project demonstrates how you can write your own VR application using OpenXR and Vulkan. These are its main features:

• Basic rendering of example scene to the headset and into a resizeable mirror view on your desktop monitor.
• Focus on easy to read and understand C++ without smart pointers, inheritance, templates, etc.
• Usage of the Vulkan multiview extension for extra performance.
• Warning-free code base spread over a small handful of classes.
• No OpenXR or Vulkan validation errors or warnings.
• CMake project setup for easy building.

Integrating both OpenXR and Vulkan yourself can be a daunting and painfully time-consuming task. Both APIs are very verbose and require the correct handling of countless minute details. This is why there are two main use cases where this project comes in handy:

1. Fork the repository and use it as a starting point to save yourself weeks of tedious integration work before you get to the juicy bits of VR development.
2. Reference the code while writing your own implementation from scratch, to help you out if you are stuck with a problem, or simply for inspiration.

Running the OpenXR Vulkan Example

1. Download the latest release (once available) or build the project yourself with the steps below.
2. Make sure your headset is connected to your computer.
3. Run the program!

Building the OpenXR Vulkan Example

1. Install the Vulkan SDK version 1.3 or newer.
2. Install CMake version 3.1 or newer.
3. Clone the repository and generate build files.
4. Build!

The repository includes binaries for all dependencies except the Vulkan SDK on Windows. These can be found in the external folder. You will have to build these dependencies yourself on other platforms. Use the adress and version tag or commit hash in version.txt to ensure compatibility. Please don't hesitate to open a pull request if you have built dependencies for previously unsupported platforms.

Attributions

Asset	Title	Author	License
models/Beetle.obj	Car Scene	toivo	CC BY 4.0
models/Bike.obj	Sci-fi Hover Bike 04	taktelon	CC BY 4.0
models/Car.obj	GAZ-21	Ashkelon	CC BY 4.0
models/Hand.obj	Hand Anatomy Reference	Ant B-D	CC BY 4.0
models/Ruins.obj	Ancient Ruins Pack	Toni García Vilche	CC BY 4.0