src/speed-plot.vala

   1 using Gtk;
   2 using Gpx;
   3 using GLib;
   4
   5 namespace Gpx
   6 {
   7     public class Graph: Gtk.EventBox
   8     {
   9         private Gpx.Track track = null;
  10         private Pango.FontDescription fd = null;
  11         private Cairo.Surface surf = null;
  12         private int LEFT_OFFSET=60;
  13         private int BOTTOM_OFFSET=30;
  14
  15         public Graph ()
  16         {
  17             this.fd = new Pango.FontDescription();//from_string("sans mono");
  18             fd.set_family("sans mono");
  19             this.app_paintable = true;
  20             this.visible_window = true;
  21             this.size_allocate.connect(size_allocate_cb);
  22         }
  23
  24         public void set_track(Gpx.Track track)
  25         {
  26             this.track =track;
  27             /* Invalidate the previous plot, so it is redrawn */
  28             this.surf = null;
  29             /* Force a redraw */
  30             this.queue_draw();
  31         }
  32         /**
  33          * Private functions
  34          */
  35         private void size_allocate_cb(Gdk.Rectangle alloc)
  36         {
  37             /* Invalidate the previous plot, so it is redrawn */
  38             this.surf = null;
  39         }
  40         override bool expose_event(Gdk.EventExpose event)
  41         {
  42             stdout.printf("Expose event\n");
  43             var ctx = Gdk.cairo_create(this.window);
  44             /* If no valid surface, render it */
  45             if(surf == null)
  46                 update_surface(this);
  47
  48             /* Draw the actual surface on the widget */
  49             ctx.set_source_surface(this.surf, 0, 0);
  50             Gdk.cairo_region(ctx, event.region);
  51             ctx.clip();
  52             ctx.paint();
  53             return false;
  54         }
  55         private void update_surface(Gtk.Widget win)
  56         {
  57             var ctx = Gdk.cairo_create(win.window);
  58             this.surf = new Cairo.Surface.similar(ctx.get_target(),Cairo.Content.COLOR_ALPHA,win.allocation.width, win.allocation.height);
  59             ctx = new Cairo.Context(this.surf);
  60
  61             /* Paint background white */
  62             ctx.set_source_rgba(1,1,1,1);
  63             ctx.paint();
  64             if(this.track == null) return;
  65
  66             double max_speed = track.max_speed;
  67             double elapsed_time = track.get_total_time();
  68             ctx.translate(LEFT_OFFSET,20);
  69             Point f = track.points.data;
  70             stdout.printf("%f\n", f.get_time());
  71
  72             /* Draw Grid */
  73             double graph_width = win.allocation.width-LEFT_OFFSET-10;
  74             double graph_height = win.allocation.height-20-BOTTOM_OFFSET;
  75
  76             var layout = Pango.cairo_create_layout(ctx);
  77             double j =0.0;
  78             double step_size = (graph_height)/8.0;
  79             ctx.set_source_rgba(0.2, 0.2, 0.2, 0.6);
  80             ctx.set_line_width(1);
  81             for(j=graph_height;j>0.0;j-=step_size){
  82                 ctx.move_to(0.0,j);
  83                 ctx.line_to(graph_width,j);
  84                 ctx.stroke();
  85
  86             }
  87             /* Draw speed and ticks */
  88             ctx.set_source_rgba(0.0, 0.0, 0.0, 1.0);
  89             double size = LEFT_OFFSET/("%.1f".printf(max_speed).length);
  90             if(size > step_size) size = step_size;
  91             fd.set_absolute_size(size*1024);
  92             layout.set_font_description(fd);
  93             for(j=0;j<graph_height;j+=step_size){
  94                 double speed = max_speed*((graph_height-j)/graph_height);
  95                 var text = "%.1f".printf(speed);
  96                 int w,h;
  97                 layout.set_text(text,-1);
  98                 layout.get_pixel_size(out w, out h);
  99                 ctx.move_to(-w-5, j-h/2.0);
 100                 Pango.cairo_layout_path(ctx, layout);
 101                 ctx.fill();
 102
 103                 ctx.move_to(-4, j);
 104                 ctx.line_to(0, j);
 105                 ctx.stroke();
 106             }
 107             /* Draw axis */
 108             ctx.move_to(0.0,0.0);
 109             ctx.set_source_rgba(0.0, 0.0, 0.0, 1);
 110             ctx.set_line_width(1.5);
 111             ctx.line_to(0.0, graph_height);
 112             ctx.line_to(graph_width, graph_height);
 113             ctx.stroke();
 114
 115
 116             /* Draw the graph */
 117             ctx.set_source_rgba(0.1, 0.2, 0.3, 1);
 118             ctx.set_line_width(1);
 119             weak List<Point?> iter = track.points.first();
 120             ctx.move_to(0.0, graph_height);
 121             while(iter.next != null)
 122             {
 123                 weak List<Point?> now = iter.next;
 124                 double time_offset = (iter.data.get_time()-f.get_time());
 125                 ctx.line_to(graph_width*(double)(time_offset/(double)elapsed_time),graph_height*(double)(1.0-track.calculate_point_to_point_speed(now.data, iter.data)/max_speed));
 126                 iter = iter.next;
 127             }
 128             ctx.line_to(graph_width, graph_height);
 129             ctx.close_path();
 130             ctx.stroke_preserve();
 131
 132             ctx.set_source_rgba(0.1, 0.2, 0.8, 0.5);
 133             ctx.fill();
 134
 135
 136             iter = track.points.first();
 137
 138             ctx.set_source_rgba(0.0, 0.0, 0.0, 1.0);
 139             fd.set_absolute_size(12*1024);
 140             layout.set_font_description(fd);
 141             uint interval = (uint)elapsed_time/((uint)(graph_width/(5*12.0)));
 142             int current = 0;
 143             stdout.printf("interval %u\n", interval);
 144             uint i;
 145             for(i=0; i < elapsed_time; i+= interval)
 146             {
 147                 if(graph_width*(1-(i/elapsed_time)) > 2.5*12 ){
 148                     int w,h;
 149                     var text = "%02i:%02i".printf((int)i/3600, ((int)i%3600)/60);
 150                     layout.set_text(text,-1);
 151                     layout.get_pixel_size(out w, out h);
 152                     ctx.move_to(graph_width*(double)(i/elapsed_time)-w/2.0, graph_height+10);
 153                     Pango.cairo_layout_path(ctx, layout);
 154                     ctx.fill();
 155
 156
 157                     ctx.move_to(graph_width*(double)(i/elapsed_time), graph_height);
 158                     ctx.line_to(graph_width*(double)(i/elapsed_time), graph_height+5);
 159                     ctx.stroke();
 160                 }
 161                 current++;
 162             }
 163
 164             /* Draw average speed */
 165             var avg = track.get_track_average();
 166             ctx.set_source_rgba(0.0, 0.7, 0.0, 0.7);
 167             ctx.move_to(0.0, graph_height*(1-avg/max_speed));
 168             ctx.line_to(graph_width, graph_height*(1-avg/max_speed));
 169             ctx.stroke();
 170
 171
 172             /* Draw moving speed */
 173             time_t moving_time;
 174             avg = track.calculate_moving_average(out moving_time);
 175             ctx.set_source_rgba(0.7, 0.0, 0.0, 0.7);
 176             ctx.move_to(0.0, graph_height*(1-avg/max_speed));
 177             ctx.line_to(graph_width, graph_height*(1-avg/max_speed));
 178             ctx.stroke();
 179
 180             {
 181                 int w,h;
 182                 ctx.set_source_rgba(0.0, 0.0, 0.0, 1.0);
 183                 fd.set_absolute_size(12*1024);
 184                 layout.set_font_description(fd);
 185                 layout.set_text("Speed (km/h) vs Time (HH:MM)",-1);
 186                 layout.get_pixel_size(out w, out h);
 187                 ctx.move_to(graph_width/2-w/2, -20);
 188                 Pango.cairo_layout_path(ctx, layout);
 189                 ctx.fill();
 190             }
 191         }
 192     }
 193 }