audacity/src/TrackPanelDrawable.h

/**********************************************************************

Tenacity

TrackPanelDrawable.h

Paul Licameli

**********************************************************************/

#ifndef __AUDACITY_TRACK_PANEL_DRAWABLE__
#define __AUDACITY_TRACK_PANEL_DRAWABLE__



#include <wx/gdicmn.h> // for wxRect

struct TrackPanelDrawingContext;
class wxRect;

/// \brief Drawing interface common to cells, groups of cells, and temporary handles in CellularPanel
class TENACITY_DLL_API TrackPanelDrawable {
public:
   virtual ~TrackPanelDrawable() = 0;

   // Drawing functions of the subdivision are visited repeatedly in one
   // painting if their areas (as computed by DrawingArea) intersect the
   // panel area, and depending on iPass may overpaint results of previous
   // passes.
   // Drawing function is given the rectangle computed by DrawingArea.
   // iPass counts zero-based up to some limit given to CellularPanel::Draw.
   // Default implementation does nothing.
   virtual void Draw(
      TrackPanelDrawingContext &context, const wxRect &rect, unsigned iPass );

   // For drawing purposes, a cell might require a bigger rectangle than for
   // hit-test purposes, spilling over into other parts of the partition of the
   // panel area.
   // Default implementation returns rect unchanged.
   // TrackPanelContext is passed in because sometimes a drawing context is
   // needed for text extent calculations.
   virtual wxRect DrawingArea(
      TrackPanelDrawingContext &context,
      const wxRect &rect, const wxRect &panelRect, unsigned iPass );

   // Utilities for implementing DrawingArea:
   static inline wxRect MaximizeWidth(
      const wxRect &rect, const wxRect &panelRect ) {
      return { panelRect.x, rect.y, panelRect.width, rect.height };
   }

   static inline wxRect MaximizeHeight(
      const wxRect &rect, const wxRect &panelRect ) {
      return { rect.x, panelRect.y, rect.width, panelRect.height };
   }
};

#endif