feat(gui): add GUI components and displays

Source/GUI/LFODisplay.cpp

@@ -0,0 +1,128 @@
+#include "LFODisplay.h"
+
+namespace serum
+{
+
+void LFODisplay::setShapeData (const std::vector<float>& data, int s)
+{
+    steps = juce::jlimit (2, 64, s);
+    shapeData = data;
+    if ((int) shapeData.size() < 64)
+        shapeData.resize (64, 0.0f);
+    repaint();
+}
+
+float LFODisplay::valueAt (float phase) const noexcept
+{
+    switch ((LfoShape) shape)
+    {
+        case LfoShape::Sine:      return std::sin (phase * 6.2831853f);
+        case LfoShape::Triangle:  return 1.0f - 4.0f * std::abs (phase - 0.5f);
+        case LfoShape::Saw:       return 2.0f * phase - 1.0f;
+        case LfoShape::Square:    return (phase < 0.5f) ? 1.0f : -1.0f;
+        case LfoShape::SampleHold:
+        {
+            const int step = juce::jlimit (0, 15, (int) (phase * 16.0f));
+            return ((step * 2654435761u) & 0xffffu) / 32768.0f - 1.0f;
+        }
+        case LfoShape::StepSeq:
+        {
+            const int idx = juce::jlimit (0, steps - 1, (int) (phase * steps));
+            return shapeData.empty() ? 0.0f : shapeData[(size_t) idx];
+        }
+        case LfoShape::Freehand:
+        {
+            if (shapeData.empty()) return 0.0f;
+            const float pos = phase * (float) (steps - 1);
+            const int i0 = (int) pos;
+            const int i1 = juce::jmin (i0 + 1, steps - 1);
+            const float frac = pos - (float) i0;
+            return shapeData[(size_t) i0] * (1.0f - frac) + shapeData[(size_t) i1] * frac;
+        }
+        default: return 0.0f;
+    }
+}
+
+void LFODisplay::paint (juce::Graphics& g)
+{
+    const auto b = getLocalBounds().toFloat();
+    g.setColour (juce::Colours::black.withAlpha (0.4f));
+    g.fillRoundedRectangle (b, 4.0f);
+    g.setColour (theme::outline);
+    g.drawRoundedRectangle (b.reduced (0.5f), 4.0f, 1.0f);
+
+    const float midY = b.getCentreY();
+    g.setColour (theme::outline);
+    g.drawLine (b.getX() + 4.0f, midY, b.getRight() - 4.0f, midY, 1.0f);
+
+    // Editable shapes show step markers.
+    if (shape == (int) LfoShape::StepSeq)
+    {
+        const float stepW = (b.getWidth() - 8.0f) / (float) steps;
+        for (int i = 0; i < steps; ++i)
+        {
+            const float v = shapeData.empty() ? 0.0f : shapeData[(size_t) i];
+            const float x = b.getX() + 4.0f + stepW * i;
+            const float y = midY - v * (b.getHeight() * 0.42f);
+            g.setColour (theme::amber);
+            g.fillRect (x + 1.0f, juce::jmin (y, midY), stepW - 2.0f, std::abs (midY - y));
+        }
+    }
+
+    juce::Path path;
+    path.startNewSubPath (b.getX() + 4.0f, midY);
+    const int n = 256;
+    for (int i = 0; i <= n; ++i)
+    {
+        const float phase = (float) i / (float) n;
+        const float v = valueAt (phase);
+        const float x = b.getX() + 4.0f + phase * (b.getWidth() - 8.0f);
+        const float y = midY - v * (b.getHeight() * 0.42f);
+        if (i == 0) path.startNewSubPath (x, y);
+        else path.lineTo (x, y);
+    }
+    g.setColour (theme::green);
+    g.strokePath (path, juce::PathStrokeType (1.5f));
+}
+
+void LFODisplay::editAt (float x, float y)
+{
+    const auto b = getLocalBounds().toFloat();
+    const float midY = b.getCentreY();
+    const float normX = juce::jlimit (0.0f, 1.0f, (x - b.getX() - 4.0f) / (b.getWidth() - 8.0f));
+    const float v = juce::jlimit (-1.0f, 1.0f, (midY - y) / (b.getHeight() * 0.42f));
+
+    if (shapeData.empty())
+        shapeData.assign (64, 0.0f);
+
+    if (shape == (int) LfoShape::StepSeq)
+    {
+        const int idx = juce::jlimit (0, steps - 1, (int) (normX * steps));
+        shapeData[(size_t) idx] = v;
+    }
+    else if (shape == (int) LfoShape::Freehand)
+    {
+        const int idx = juce::jlimit (0, steps - 1, (int) (normX * steps));
+        shapeData[(size_t) idx] = v;
+    }
+    else
+    {
+        return;
+    }
+
+    if (onEdited)
+        onEdited (shapeData, steps);
+    repaint();
+}
+
+void LFODisplay::mouseDown (const juce::MouseEvent& e)
+{
+    editAt (e.x, e.y);
+}
+
+void LFODisplay::mouseDrag (const juce::MouseEvent& e)
+{
+    editAt (e.x, e.y);
+}
+
+} // namespace serum