SDL3 GPU is pretty good

Apps

The repository contains two (WIP) apps for now:

• pbr: GLTF model viewer, with supports for most features from the GLTF PBR spec
• grass: A dense, real-time grassblade field simulation aiming to offload as much as possible to the GPU (terrain and grassblade generation, frustum culling and draw-call generation are all GPU-driven thanks to compute shaders)

Common features

• Minimal framework and collection of utilities to reduce boilerplate
• Support for HDR textures and cubemaps
• Support for KTX file format
• Image based lighting
• Multiple HDR post-processing shaders
• Generation of missing tangents and bitangents at runtime

build

Program

The project uses CMake Presets for easy configuration:

mkdir build
cmake --preset rel-ninja # or `debug-ninja`/`debug-asan`
cmake --build --preset release # or `debug`/`asan`

You can then run it:

build/rel-ninja/sdl_demos [APP_NAME]

Valid app names are pbr and grass.

The following libraries are expected to be installed system-wide:

• SDL3 (you can choose to build by defining the BUILD_SDL CMake option)
• glm
• simdjson (it's supposed to be fetched & built as a dependency of fastgltf, but it doesn't work for me)

These are built along with the project (make sure to clone submodules):

• spdlog
• stb
• imgui
• fastgltf
• Catch2
• ktx
• mikktspace

Shaders

Use the shaders.sh script to build the shaders related to the app you want to run:

# TODO: add this as a CMake target someday
./shaders.sh grass
./shaders.sh pbr