/vkcompute

Primary LanguageC++

vkCompute

A minimal example and template repo for GPU computation using vulkan.

Who / What is this for?

This can be used as a starter / template repo for experimenting with compute shaders for general purpose computation.

Hopefully it gets people to an end-to-end GPU computation working faster instead of having to transpose "hello triangle" tutorials into non-rendering general purpose compute use cases while trying to learning vulkan at the same time (which was mostly my experience).

What does it do?

  1. main.cpp sets up input and output arrays of numbers on the host with the help of vulkan utility functions in vkcompute.hpp
  2. Calls out to execute a softmax computation implementated as a GPU compute shader in softmax.glsl (which is compiled to an SPIR-V artifact build/softmax.spv.
  3. After the computation is finished, main.cpp copies the output back to the host and prints the result.

Build dependencies are managed by conan and the build itself is defined using cmake (CMakeLists.txt. The Makefile has a few convenient aliases for building and running.

Dependencies

  • conan for installing library dependencies described in conanfile.txt.
  • cmake for building.
  • vulkan SDK - vulkan SDK includes vulkan headers and library files.
  • glslc - glsl compiler which compiles src/softmax.glsl to build/softmax.spv.

Optional:

rg and entr command line tools are used in the Makefile for continuous build watching. clang-format is also used by the makefile to automate formatting cleanup.

Project Structure

  • src/main.cpp the main entrypoint for the program - sets up, runs the shader computation, and prints the result.
  • src/vkcompute.hpp header file of helper functions supporting setting up vulkan.
  • src/softmax.glsl compute shader implementing a softmax computation as a (single workgroup) parallel sum reduction on the GPU.

Building

Building and running requires two things:

  1. Building the computer shader src/softmax.glsl to create a SPIR-V shader artifact build/softmax.spv
  2. Building the main program with cmake

On mac, the program can be built with make build/softmax.spv to build the shader followed by make run-osx to build and run the program (see the Makefile for details if you want to do the steps manually.

On linux, the program can be built with make build/softmax.spv to build the shader followed by make run-linux to build and run the program. [NOTE / TODO : it may crash if you don't have the khronos compatibility extension - TODO make this optional]

Contact and Contributions

You can find me via DM on twitter @austinvhuang.