This is tool takes an equirectangular hdr image and generates irradiance and specular cubemap textures for image-based lighting used in Physically Based Shading.
For the moment the tool outputs .png and ktx files for the textures. The Ktx format is RGB16F and is not compressed.
The tool requires Bazel build process.
Mac/Linux: CMAKE is also required.
Replace the image in data/source.hdr with a different equirectangular image that you want to use for generating the maps.
Once you're set up, run in command line:
$ bazel run :tool
And the images will be generated and outputted to the bazel-bin/tool.runfiles/MAIN folder.
Hopefully in the near future:
- Take input image from cmd args.
- Control resolution and outputs from cmd args.
- Remove cmake dependancy on Mac/Linux.
I made the tool because I needed something to integrate with my build process. I hope it'll be useful for you.
The tool is based on these tutorials:
https://learnopengl.com/PBR/IBL/Diffuse-irradiance
https://learnopengl.com/PBR/IBL/Specular-IBL
The credit should really go to Joey de Vries for making an amazing website and fantastic tutorials :)