Plot decimation

Author: highperformancecoder

Makefile

@@ -143,10 +143,6 @@ cdhdrs: $(CDHDRS:%=include/%) graphcode.cd $(CLASSDESC)
 
 include/graphcode.cd: graphcode/graphcode.h
 
-# newarrays needs to be preexpanded ...
-#include/newarrays.cd: include/newarrays.exh
-#	classdesc -I $(CDINCLUDE) -I $(ECOLAB_HOME)/include $(ACTIONS) <$< >$@
-
 include/newarrays.exh: include/newarrays.h utils/wrap
 	gcc -E -P $(CONT_FLAG) $< |wrap >$@
 

include/plot.h

@@ -69,16 +69,19 @@ namespace ecolab
     void extendPalette() {palette.push_back(LineStyle());}
 
   private:    
-    std::string m_image;
     std::vector<std::vector<double> > x;
     std::vector<std::vector<double> > y;
-
+    std::vector<unsigned> decimation, decimate;
+    const unsigned maxPoints=1000; ///< maximum number of points to plot without decimation
+    
     CLASSDESC_ACCESS(Plot);
 
     // internal common routine for add()
     void addNew(cairo::Surface& surf, bool doRedraw, 
                 const unsigned *startPen, const unsigned *finishPen, int numPt);
 
+    
+    
     double iflogx(double x) const {return logx? log10(x): x;}
     double iflogy(double y) const {return logy? log10(y): y;}
 
@@ -139,21 +142,6 @@ namespace ecolab
     /// set min/max to autoscale on contained data
     void setMinMax();
 
-    /// set/get the Tk image that this class writes to.
-    std::string Image() const {return m_image;}
-    std::string Image(const std::string& im, bool transparency=true);
-//    string image(TCL_args args) {
-//      if (args.count>0)
-//        {
-//          string imgName=args.str();
-//          bool transparency=true;
-//          if (args.count) transparency=args;
-//          return Image(imgName,transparency);
-//        }
-//      else
-//        return Image();
-//    }
-    
     /// draw the plot onto a given surface
     virtual void draw(cairo::Surface&);
     void draw(cairo_t*, double width, double height) const;
@@ -183,14 +171,6 @@ namespace ecolab
     /// remove all pens from pen and above from plot
     void removePensFrom(unsigned pen);
 
-//    //serialisation support (surface is not auto-serialisable)
-//    void pack(classdesc::pack_t& p) const override {p<<m_image<<x<<y<<minx<<maxx<<miny<<maxy;}
-//
-//    void unpack(classdesc::pack_t& p) override {
-//        p>>m_image>>x>>y>>minx>>maxx>>miny>>maxy;
-//        Image(m_image);
-//    }
-
     /// add a point to the graph withour redrwaing anything
     void addPt(unsigned pen, double x, double y);
 
@@ -222,16 +202,23 @@ namespace ecolab
                    const array_ns::array<unsigned>& pens, 
                    double x1, const array_ns::array<double>& y1);
 
-    template <class C>
-    void add(cairo::Surface& surf, unsigned pen, const C& x1, const C& y1)
+    void checkAddPen(unsigned pen)
     {
-      assert(x1.size()==y1.size());
-      bool doRedraw=false;
       if (pen>=x.size())
         {
           x.resize(pen+1);
           y.resize(pen+1);
+          decimation.resize(pen+1,1);
+          decimate.resize(pen+1);
         }
+    }
+    
+    template <class C>
+    void add(cairo::Surface& surf, unsigned pen, const C& x1, const C& y1)
+    {
+      assert(x1.size()==y1.size());
+      bool doRedraw=false;
+      checkAddPen(pen);
       for (size_t i=0; i<x1.size(); ++i)
         {
           doRedraw|=x1[i]<minx||x1[i]>maxx || y1[i]<miny||y1[i]>maxy;
@@ -245,11 +232,7 @@ namespace ecolab
     /// \a x and \a y should have the same size, if not, the larger is truncated
     void setPen(unsigned pen, const double* xx, const double* yy, size_t sz)
     {
-      if (pen>=x.size())
-        {
-          x.resize(pen+1);
-          y.resize(pen+1);
-        }
+      checkAddPen(pen);
       x[pen].assign(xx, xx+sz);
       y[pen].assign(yy, yy+sz);
     }

models/panmictic_ecolab.py

@@ -49,7 +49,7 @@ def step():
     nsp=len(ecolab.species)
     statusBar.configure(text=f't={ecolab.tstep()} nsp:{nsp}')
     plot('No. species',ecolab.tstep(),nsp)
-    plot('Density',ecolab.tstep(),ecolab.density(), pens=ecolab.species())
+    #plot('Density',ecolab.tstep(),ecolab.density(), pens=ecolab.species())
     plot('Conn-Nsp',ecolab.connectivity(),nsp)
     plot('Conn*density',ecolab.tstep(),ecolab.connectivity()*nsp)
 

src/plot.cc

@@ -251,21 +251,6 @@ namespace ecolab
   int PlotSurface::width() const {return surface? surface->width():0;}
   int PlotSurface::height() const {return surface? surface->height():0;}
 
-
-  string Plot::Image(const string& im, bool transparency)
-  {
-#if defined(TK)
-//    Tk_PhotoHandle photo = Tk_FindPhoto(interp(), im.c_str());
-//    if (photo)
-//      {
-//        surface.reset(new cairo::TkPhotoSurface(photo,transparency));
-//        cairo_surface_set_device_offset(surface->surface(),0.5*surface->width(),0.5*surface->height());
-//      }
-//    redraw();
-#endif
-    return m_image=im;
-  }
-
   string Plot::axisLabel(double x, double scale, bool percent) const
   {
     char label[30];
@@ -311,8 +296,10 @@ namespace ecolab
 
   void Plot::removePensFrom(unsigned pen)
   {
-    if (x.size()>pen) x.resize(pen);
-    if (y.size()>pen) y.resize(pen);
+    x.resize(pen);
+    y.resize(pen);
+    decimation.resize(pen);
+    decimate.resize(pen);
     redraw();
   }
 
@@ -1101,6 +1088,7 @@ namespace ecolab
   void Plot::clear()
   {
     x.clear(); y.clear();
+    decimation.clear(); decimate.clear();
     redraw();
   }
 
@@ -1167,13 +1155,25 @@ namespace ecolab
 
   void Plot::addPt(unsigned pen, double xx, double yy)
   {
-    if (pen>=x.size())
+    checkAddPen(pen);
+    if (decimate[pen]==0)
       {
-        x.resize(pen+1);
-        y.resize(pen+1);
+        x[pen].push_back(xx);
+        y[pen].push_back(yy);
+        if (x[pen].size()>maxPoints)
+          {
+            decimation[pen]*=2;
+            for (size_t i=0; i<x[pen].size(); i+=2)
+              {
+                x[pen][i/2]=x[pen][i];
+                y[pen][i/2]=y[pen][i];
+              }
+            x[pen].resize(x[pen].size()/2);
+            y[pen].resize(y[pen].size()/2);
+          }
       }
-    x[pen].push_back(xx);
-    y[pen].push_back(yy);
+    if (++decimate[pen]>=decimation[pen])
+      decimate[pen]=0;
   }
 
   void Plot::add(cairo::Surface& surf, unsigned pen, 
@@ -1189,33 +1189,17 @@ namespace ecolab
   {
     bool doRedraw=x1<minx||x1>maxx;
     unsigned maxPen=max(pens);
-    if (maxPen>=x.size())
-        {
-          x.resize(maxPen+1);
-          y.resize(maxPen+1);
-        }
-      for (size_t p=0; p<y1.size(); ++p)
-        {
-          unsigned pen=pens[p];
-          double yy=y1[pen];
-          doRedraw|=yy<miny || yy>maxy;
-          x[pen].push_back(x1);
-          y[pen].push_back(yy);
-        }
-      addNew(surf, doRedraw, pens.begin(), pens.end(), 1);
-    }      
-
-//  void Plot::plot(TCL_args args)
-//  {
-//    if (args.count>1) 
-//      {
-//        double x=args;
-//        array_ns::array<double> y; args>>y;
-//        assert(args.count==0);
-//        array_ns::array<unsigned> pens=pcoord(y.size());
-//        add(pens,x,y);
-//      }
-//  }
+    checkAddPen(maxPen);
+    for (size_t p=0; p<y1.size(); ++p)
+      {
+        unsigned pen=pens[p];
+        double yy=y1[pen];
+        doRedraw|=yy<miny || yy>maxy;
+        x[pen].push_back(x1);
+        y[pen].push_back(yy);
+      }
+    addNew(surf, doRedraw, pens.begin(), pens.end(), 1);
+  }      
 
   string stripPangoMarkup(const string& markedUptext)
   {