Offscreen Rendering

Rendering into a custom framebuffer, also known as off-screen rendering or rendering to a texture, plays a crucial role in numerous scenarios within computer graphics and game development. This repo is just an example that demonstrates how this can be achieved using the Qt framework (version 6).

Build and run

cmake -B build -S .
cmake --build build --parallel

Dependencies

This project uses Qt (Qt Quick, Qt QML, Qt OpenGL). The required Ubuntu packages for Qt and other dependencies are listed in the Dockerfile included in this repository.

Usage

When running inside Docker, the output image will be written to a mounted folder. Specify the output path using the --output or -o CLI argument:

./build/offscreen_sample --output /output/image.png

Make sure to mount a host directory to /output in your Docker container to access the generated image.

Example Docker run (headless mode)

docker run --rm -u $(id -u):$(id -g) -v $(pwd)/output:/output $(docker build . -q)

This will save the rendered image to the output folder on your host machine.