# MonoStep

A monophonic 2-oscillator step-sequencer synthesizer implemented as a VST3 plugin with JUCE.

## Features

- 16-step monophonic sequencer (pattern length 1-16)
- 2 oscillators with sine / triangle / saw / square waves, detune, and mix
- Subtractive filter (cutoff, resonance) with ADSR and glide
- Per-step gates, pitches (+/- 6 semitones), fine tuning (cents), and slide (legato)
- Matrix editor with click-to-toggle steps, drag-to-pitch, and a slide row
- Rotary-knob GUI with zoom (100% - 200%), a step panel with fine-tune, and a
  live red play-position marker
- Footer status bar showing the git commit and build date
- Pattern stored in the plugin state (save/restore with the DAW)

## Requirements

- macOS 12.0 or later (arm64)
- CMake 3.22 or newer
- A C++17 compiler (Xcode command-line tools)
- [JUCE](https://github.com/juce-framework/JUCE)

## Building

The build expects JUCE in `../juce` relative to this repository. If JUCE lives
somewhere else, point `JUCE_DIR` at it during configuration.

```sh
# 1. Get JUCE next to this repository:
git clone --depth 1 https://github.com/juce-framework/JUCE.git ../juce

# 2. Configure:
cmake -S . -B build

# or, for a custom JUCE location:
cmake -S . -B build -DJUCE_DIR=/path/to/juce

# 3. Build the plugin:
cmake --build build --target MonoStep_VST3
```

The VST3 plugin is written to:

```
build/MonoStep_artefacts/Release/VST3/MonoStep.vst3
```

### Quick start with make

A `Makefile` wraps configure, build, and install. Just run `make`:

```sh
make          # build the plugin and copy it into ~/Library/Audio/Plug-Ins/VST3/
make test     # build and run the headless host test
make clean    # remove the build directory
```

### Installing (manual copy)

The VST3 plugin ships as a macOS bundle (`MonoStep.vst3`). Copy the whole
bundle into your DAW's VST3 directory:

```sh
cp -R build/MonoStep_artefacts/Release/VST3/MonoStep.vst3 \
      ~/Library/Audio/Plug-Ins/VST3/
```

Notes for macOS:

- The per-user VST3 directory is `~/Library/Audio/Plug-Ins/VST3/`; create it
  with `mkdir -p` if it does not exist. A system-wide copy would go to
  `/Library/Audio/Plug-Ins/VST3/` but requires `sudo`.
- When updating, remove the old bundle first (`rm -rf` on the `MonoStep.vst3`
  inside the target directory) so stale files do not remain.
- Your DAW may cache the plugin list — quit and relaunch it (or rescan plugins)
  after installing before looking for MonoStep.

## Running the tests

Build the headless host test and run it against the built plugin:

```sh
cmake --build build --target MonoStepTestHost
build/MonoStepTestHost_artefacts/Release/MonoStepTestHost \
    build/MonoStep_artefacts/Release/VST3/MonoStep.vst3
```

The host scans the VST3, renders a buffer, and verifies that the pattern
survives a state save/load round-trip. Expect `ALL TESTS PASSED`.