# gui module

## Owned files

- Related editor implementation: `../PluginEditor.h`, `../PluginEditor.cpp`
- SerumLookAndFeel.h
- Knob.h, Knob.cpp
- Slider.h, Slider.cpp
- ToggleButton.h, ToggleButton.cpp
- Display.h, Display.cpp
- Panel.h, Panel.cpp
- WaveformDisplay.h, WaveformDisplay.cpp
- FilterDisplay.h, FilterDisplay.cpp
- EnvelopeDisplay.h, EnvelopeDisplay.cpp
- LFODisplay.h, LFODisplay.cpp

## Rules

- Draw all controls through `SerumLookAndFeel`.
- Use `theme::` colours from Resources.h instead of hardcoded colour values.
- Own GUI attachments with `std::unique_ptr`.
- Own component children by value or with `std::unique_ptr`; `addAndMakeVisible` only attaches and shows them, and does not manage their lifetime.
- Refresh visuals from a `juce::Timer` callback on the message thread, not from the audio thread.
- Keep layout constants in the `layout` namespace and derive every position from them.
- Use `std::function` formatters for value readouts.
- Reference `ids::` for APVTS parameter IDs.

## IF-THEN

- IF a control reads a DSP value THEN refresh it on the message thread from a thread-safe snapshot or atomic value. A `timerCallback` alone does not make a shared DSP read safe.
- IF a raw parameter pointer is dereferenced THEN null-guard it first.

## Examples

```cpp
// BAD: unchecked raw parameter dereference
const float v = processor.parameters.getRawParameterValue (ids::f1Cutoff)->load();
```

```cpp
// GOOD: null guard with fallback
const float v = processor.parameters.getRawParameterValue (ids::f1Cutoff)
                    ? processor.parameters.getRawParameterValue (ids::f1Cutoff)->load()
                    : 0.0f;
```

This file overrides /AGENT.md where they conflict.