tempo_curve_canvas_renderer.h

// SPDX-FileCopyrightText: © 2026 Alexandros Theodotou <alex@zrythm.org>
// SPDX-License-Identifier: LicenseRef-ZrythmLicense
 
#pragma once
 
#include <vector>
 
#include <QtCanvasPainter/qcanvaslineargradient.h>
#include <QtCanvasPainter/qcanvaspainter.h>
#include <QtCanvasPainter/qcanvaspainteritemrenderer.h>
 
namespace zrythm::gui::qquick
{
 
class TempoCurveCanvasItem;

class TempoCurveCanvasRenderer : public QCanvasPainterItemRenderer
{
public:
  TempoCurveCanvasRenderer () = default;
  Q_DISABLE_COPY_MOVE (TempoCurveCanvasRenderer)
 
  void synchronize (QCanvasPainterItem * item) override;
  void paint (QCanvasPainter * painter) override;
 
private:
  struct CachedTempoEvent
  {
    double tick;
    double bpm;
    bool   linear; 
  };
 
  QColor curve_color_{ "#009DFF" };
  float  scroll_x_{ 0.0f };
  float  scroll_x_plus_width_{ 0.0f };
  float  px_per_tick_{ 0.0f };
  float  lane_height_{ 0.0f };
  float  min_bpm_{ 100.0f };
  float  max_bpm_{ 160.0f };
  // Base tempo at tick 0 (governs the region from 0 up to the first object).
  double                        base_bpm_{ 120.0 };
  std::vector<CachedTempoEvent> cached_events_;
};
 
} // namespace zrythm::gui::qquick