// Headless Mode Documentation
// Workspace: demo (shared across all workspaces)

# Headless Mode

Minimal GPU/platform stubs for testing without graphics.

## Use Cases

- CI/CD without GPU
- Audio/tracker iteration
- Timeline validation
- Fast testing cycles

## Build

```bash
cmake -B build_headless -DDEMO_HEADLESS=ON
cmake --build build_headless -j4
```

Or use the test script:
```bash
./scripts/test_headless.sh
```

## Usage

```bash
# 30s simulation (default)
./build_headless/demo64k --headless

# Custom duration
./build_headless/demo64k --headless --duration 60

# Audio validation
./build_headless/demo64k --dump_wav test.wav
```

Progress printed every 5s.

## Implementation

- **GPU stub:** Validates lifecycle, maintains MainSequence
- **Platform stub:** Simulates 60Hz time progression
- **Main loop:** Audio updates without rendering

## vs STRIP_EXTERNAL_LIBS

| Feature | HEADLESS | STRIP_EXTERNAL_LIBS |
|---------|----------|---------------------|
| Compiles | Yes | Yes |
| Runs | Yes | No |
| Audio | Full | No-op |
| Timeline | Full | No |
| Tests | Pass | Fail |

See `src/gpu/headless_gpu.cc` and `src/platform/headless_platform.cc` for details.