InstaGrain/Source/WaveformDisplay.h

#pragma once
#include <JuceHeader.h>
#include "GrainEngine.h"

class WaveformDisplay : public juce::Component
{
public:
    WaveformDisplay();

    void setBuffer (const juce::AudioBuffer<float>* buffer);
    void setGrainPosition (float pos) { grainPosition = pos; repaint(); }
    void setScatterRange (float range) { scatterRange = range; repaint(); }
    void setActiveGrains (const std::vector<GrainEngine::ActiveGrainInfo>& grains);

    std::function<void (float)> onPositionChanged;

    void paint (juce::Graphics& g) override;
    void resized() override;
    void mouseDown (const juce::MouseEvent& e) override;
    void mouseDrag (const juce::MouseEvent& e) override;

private:
    const juce::AudioBuffer<float>* audioBuffer = nullptr;
    juce::Path cachedWaveformPath;
    bool pathDirty = true;
    int lastWidth = 0, lastHeight = 0;
    int lastBufferSize = 0;

    float grainPosition = 0.5f;
    float scatterRange = 0.0f;
    std::vector<GrainEngine::ActiveGrainInfo> activeGrains;
    int totalSourceSamples = 0;

    void rebuildWaveformPath (juce::Rectangle<float> bounds);
    void updatePositionFromMouse (const juce::MouseEvent& e);

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (WaveformDisplay)
};