Add generic plot widget.

This widget will be used in the new Compressor2 effect but it is
designed for use in other effects as well.

Signed-off-by: Max Maisel <max.maisel@posteo.de>

src/CMakeLists.txt

@@ -949,6 +949,8 @@ list( APPEND SOURCES PRIVATE
   widgets/Overlay.h
   widgets/OverlayPanel.cpp
   widgets/OverlayPanel.h
+  widgets/Plot.cpp
+  widgets/Plot.h
   widgets/PopupMenuTable.cpp
   widgets/PopupMenuTable.h
   widgets/ProgressDialog.cpp

src/ShuttleGui.cpp

@@ -121,6 +121,7 @@ for registering for changes.
 #include "widgets/wxTextCtrlWrapper.h"
 #include "AllThemeResources.h"
 
+#include "widgets/Plot.h"
 #include "widgets/SliderTextCtrl.h"
 
 #if wxUSE_ACCESSIBILITY
@@ -777,6 +778,33 @@ void ShuttleGuiBase::AddConstTextBox(
    UpdateSizers();
 }
 
+Plot* ShuttleGuiBase::AddPlot( const TranslatableString &Prompt,
+   double x_min, double x_max, double y_min, double y_max,
+   const TranslatableString& x_label, const TranslatableString& y_label,
+   int x_format, int y_format, int count)
+{
+   HandleOptionality( Prompt );
+   AddPrompt( Prompt );
+   UseUpId();
+   if( mShuttleMode != eIsCreating )
+      return wxDynamicCast(wxWindow::FindWindowById(miId, mpDlg), Plot);
+   Plot* pPlot;
+   mpWind = pPlot = safenew Plot(GetParent(), miId,
+      x_min, x_max, y_min, y_max, x_label, y_label,
+      x_format, y_format, count,
+      wxDefaultPosition, wxDefaultSize,
+      GetStyle( SliderTextCtrl::HORIZONTAL )
+   );
+#if wxUSE_ACCESSIBILITY
+   // so that name can be set on a standard control
+   mpWind->SetAccessible(safenew WindowAccessible(mpWind));
+#endif
+   mpWind->SetName(wxStripMenuCodes(Prompt.Translation()));
+   miProp=1;
+   UpdateSizers();
+   return pPlot;
+}
+
 wxListBox * ShuttleGuiBase::AddListBox(const wxArrayStringEx &choices)
 {
    UseUpId();

src/ShuttleGui.h

@@ -28,6 +28,7 @@
 class ChoiceSetting;
 
 class wxArrayStringEx;
+class Plot;
 class SliderTextCtrl;
 
 
@@ -348,6 +349,11 @@ public:
    void AddConstTextBox(
       const TranslatableString &Caption, const TranslatableString & Value );
 
+   Plot* AddPlot( const TranslatableString &Prompt,
+      double x_min, double x_max, double y_min, double y_max,
+      const TranslatableString& x_label, const TranslatableString& y_label,
+      int x_format = 1, int y_format = 1, int count = 1 );
+
 //-- Start and end functions.  These are used for sizer, or other window containers
 //   and create the appropriate widget.
    void StartHorizontalLay(int PositionFlags=wxALIGN_CENTRE, int iProp=1);

src/widgets/Plot.cpp

@@ -0,0 +1,136 @@
+/**********************************************************************
+
+   Audacity: A Digital Audio Editor
+
+   Plot.cpp
+
+   Max Maisel
+
+*******************************************************************//**
+
+\class Plot
+\brief A customizable generic plot widget.
+
+*//*******************************************************************/
+
+
+#include "../Audacity.h"
+#include "audacity/Types.h"
+#include "Plot.h"
+#include "Ruler.h"
+#include "../AColor.h"
+#include "../Theme.h"
+#include "../AllThemeResources.h"
+
+#include <wx/brush.h>
+#include <wx/dcclient.h>
+#include <wx/dcmemory.h>
+
+Plot::Plot(wxWindow *parent, wxWindowID winid,
+   float x_min, float x_max, float y_min, float y_max,
+   const TranslatableString& xlabel, const TranslatableString& ylabel,
+   int xformat, int yformat, int count,
+   const wxPoint& pos, const wxSize& size, long style)
+   :
+   wxPanelWrapper(parent, winid, pos, size, style),
+   m_xmin(x_min), m_xmax(x_max), m_ymin(y_min), m_ymax(y_max),
+   m_plots(count)
+{
+   m_xruler = std::unique_ptr<Ruler>(safenew Ruler);
+   m_xruler->SetOrientation(wxHORIZONTAL);
+   m_xruler->SetFormat(static_cast<Ruler::RulerFormat>(xformat));
+   m_xruler->SetUnits(xlabel);
+   m_xruler->SetFlip(true);
+
+   m_yruler = std::unique_ptr<Ruler>(safenew Ruler);
+   m_yruler->SetOrientation(wxVERTICAL);
+   m_yruler->SetFormat(static_cast<Ruler::RulerFormat>(yformat));
+   m_yruler->SetUnits(ylabel);
+}
+
+void Plot::OnPaint(wxPaintEvent & evt)
+{
+   wxPaintDC dc(this);
+
+   int width, height;
+   GetSize(&width, &height);
+
+#if defined(__WXMSW__)
+   dc.Clear();
+#endif
+
+   // Ruler
+   int w = 0;
+   int h = 0;
+
+   m_xruler->SetBounds(0, 0, width, height);
+   m_xruler->SetRange(m_xmin, m_xmax);
+   m_xruler->GetMaxSize(NULL, &h);
+
+   m_yruler->SetBounds(0, 0, width, height);
+   m_yruler->SetRange(m_ymax, m_ymin);
+   m_yruler->GetMaxSize(&w, NULL);
+
+   m_xruler->SetBounds(w, height - h, width, height);
+   m_yruler->SetBounds(0, 0, w, height - h);
+
+   m_xruler->SetTickColour( theTheme.Colour( clrGraphLabels ));
+   m_yruler->SetTickColour( theTheme.Colour( clrGraphLabels ));
+
+   wxRect border;
+   border.x = w;
+   border.y = 0;
+   border.width = width - w;
+   border.height = height - h + 1;
+
+   dc.SetBrush(*wxWHITE_BRUSH);
+   dc.SetPen(*wxTRANSPARENT_PEN);
+   dc.DrawRectangle(border);
+
+   m_xruler->DrawGrid(dc, border.height, true, true, border.x, border.y);
+   m_yruler->DrawGrid(dc, border.width, true, true, border.x, border.y);
+
+   for(const auto& plot : m_plots)
+   {
+      wxASSERT(plot.xdata.size() == plot.ydata.size());
+      if(plot.xdata.size() == 0)
+         continue;
+      dc.SetPen(*plot.pen);
+
+      size_t xsize = plot.xdata.size();
+      for(size_t i = 1; i < xsize; ++i)
+      {
+         AColor::Line(dc,
+            XToScreen(plot.xdata[i-1], border),
+            YToScreen(plot.ydata[i-1], border),
+            XToScreen(plot.xdata[i], border),
+            YToScreen(plot.ydata[i], border));
+      }
+   }
+
+   dc.SetBrush(*wxTRANSPARENT_BRUSH);
+   dc.SetPen(*wxBLACK_PEN);
+   dc.DrawRectangle(border);
+   m_xruler->Draw(dc);
+   m_yruler->Draw(dc);
+}
+
+void Plot::OnSize(wxSizeEvent & evt)
+{
+   Refresh(false);
+}
+
+int Plot::XToScreen(float x, wxRect& rect)
+{
+   return rect.x + lrint((x-m_xmin)*rect.width/(m_xmax-m_xmin));
+}
+
+int Plot::YToScreen(float y, wxRect& rect)
+{
+   return rect.y + rect.height - lrint((y-m_ymin)*rect.height/(m_ymax-m_ymin));
+}
+
+BEGIN_EVENT_TABLE(Plot, wxPanelWrapper)
+   EVT_PAINT(Plot::OnPaint)
+   EVT_SIZE(Plot::OnSize)
+END_EVENT_TABLE()

src/widgets/Plot.h

@@ -0,0 +1,58 @@
+/**********************************************************************
+
+   Audacity: A Digital Audio Editor
+
+   Plot.h
+
+   Max Maisel
+
+   This class is a generic plot.
+
+**********************************************************************/
+
+#ifndef __AUDACITY_PLOT__
+#define __AUDACITY_PLOT__
+
+#include "wxPanelWrapper.h" // to inherit
+
+#include "MemoryX.h"
+
+class Ruler;
+
+struct PlotData
+{
+   std::unique_ptr<wxPen> pen;
+   std::vector<float> xdata;
+   std::vector<float> ydata;
+};
+
+class Plot : public wxPanelWrapper
+{
+   public:
+      Plot(wxWindow *parent, wxWindowID winid,
+         float x_min, float x_max, float y_min, float y_max,
+         const TranslatableString& xlabel, const TranslatableString& ylabel,
+         int xformat = 1, int yformat = 1, //Ruler::RealFormat
+         int count = 1, const wxPoint& pos = wxDefaultPosition,
+         const wxSize& size = wxDefaultSize,
+         long style = wxTAB_TRAVERSAL | wxNO_BORDER);
+
+      inline PlotData* GetPlotData(int id)
+         { return &m_plots[id]; }
+
+   private:
+      void OnPaint(wxPaintEvent & evt);
+      void OnSize(wxSizeEvent & evt);
+
+      float m_xmin, m_xmax;
+      float m_ymin, m_ymax;
+      std::vector<PlotData> m_plots;
+      std::unique_ptr<Ruler> m_xruler, m_yruler;
+
+      int XToScreen(float x, wxRect& rect);
+      int YToScreen(float y, wxRect& rect);
+
+      DECLARE_EVENT_TABLE()
+};
+
+#endif