# Login theme NX packer

`nxpack.cpp` creates a small PKG4 NX file from a directory of PNG files. It is
used for the browser login theme so the post-Chaos login artwork required by
the WASM client does not replace v83 gameplay UI data.

Directories become NX nodes. A PNG filename becomes a bitmap node with a
zero-valued `origin` child. For example:

```text
Login.img/Title/BtLogin/normal/0.png
```

becomes `Login.img/Title/BtLogin/normal/0`.

Build and run it in the pinned converter image:

```sh
g++ -std=c++17 -Wall -Wextra -Werror \
  -I src/client/includes/stb -I src/client/includes \
  scripts/nxpack/nxpack.cpp -llz4 -o .cache/tools/nxpack
.cache/tools/nxpack <theme-input-directory> nxFiles/LoginTheme.nx
```

The operator-supplied artwork and generated NX file remain ignored runtime
inputs. Do not place either under `assets/`.
