Soulcrush is a small, experimental tool to remove unused code from OpenGL shaders.

Soulcrush might some day become a full fledged GLSL minifier, but for now it only removes unused functions (functions not called directly or indirectly from main). The output from soulcrush can of course be passed to another minifier tool.

Despite the limited scope, this can still be useful. For instance, you could maintain a library of utility functions, include the whole library in your shaders (via a preprocessor or just file concatenation) and then use Soulcrush to remove unused code, and Shader Minifier to minify the output further.

Run cargo build --release, and the binary should be built as target/release/soulcrush.

Run target/release/soulcrush <filename>.glsl, and the output should be printed to standard output.

Function calls from top-level variable initializers are currently not detected correctly, which can cause too much code to be removed. Also, unused top-level variables are not currently removed.

Did I mention that this project is experimental? It has only been used for a few toy projects, so expect bugs.