gui/graph_displayer_canvas-zoom.cc
author alpar
Wed, 17 Aug 2005 22:07:35 +0000
changeset 1641 77f6ab7ad66f
parent 1606 dc4ea2010dee
child 1777 a70cee06ae9c
permissions -rwxr-xr-x
Demos' documentations include the source.
ladanyi@1606
     1
#include "graph_displayer_canvas.h"
ladanyi@1606
     2
#include "broken_edge.h"
alpar@1632
     3
#include <cmath>
hegyi@1510
     4
hegyi@1510
     5
void GraphDisplayerCanvas::zoomIn()
hegyi@1510
     6
{
hegyi@1510
     7
  set_pixels_per_unit(
hegyi@1510
     8
      (1.0 + (double) zoom_step / 100.0) * get_pixels_per_unit());
hegyi@1510
     9
}
hegyi@1510
    10
hegyi@1510
    11
void GraphDisplayerCanvas::zoomOut()
hegyi@1510
    12
{
hegyi@1510
    13
  set_pixels_per_unit(
hegyi@1510
    14
      (1.0 - (double) zoom_step / 100.0) * get_pixels_per_unit());
hegyi@1510
    15
}
hegyi@1510
    16
hegyi@1510
    17
void GraphDisplayerCanvas::zoomFit()
hegyi@1510
    18
{
hegyi@1510
    19
  // get the height and width of the canvas
hegyi@1510
    20
  Gtk::Allocation a = get_allocation();
hegyi@1510
    21
  int aw = a.get_width();
hegyi@1510
    22
  int ah = a.get_height();
hegyi@1510
    23
  // add some space
hegyi@1510
    24
  aw -= 5; if (aw < 0) aw = 0;
hegyi@1510
    25
  ah -= 5; if (ah < 0) ah = 0;
hegyi@1510
    26
hegyi@1510
    27
  // get the bounding box of the graph
hegyi@1510
    28
  double wx1, wy1, wx2, wy2;
hegyi@1510
    29
  Gnome::Canvas::Item* pCanvasItem = root();
hegyi@1510
    30
  pCanvasItem->get_bounds(wx1, wy1, wx2, wy2);
hegyi@1510
    31
hegyi@1510
    32
  // fit the graph to the window
hegyi@1510
    33
  double ppu1 = (double) aw / fabs(wx2 - wx1);
hegyi@1510
    34
  double ppu2 = (double) ah / fabs(wy2 - wy1);
hegyi@1510
    35
  set_pixels_per_unit((ppu1 < ppu2) ? ppu1 : ppu2);
hegyi@1510
    36
}
hegyi@1510
    37
hegyi@1510
    38
void GraphDisplayerCanvas::zoom100()
hegyi@1510
    39
{
hegyi@1510
    40
  set_pixels_per_unit(1.0);
hegyi@1510
    41
}
hegyi@1510
    42
hegyi@1510
    43
void GraphDisplayerCanvas::updateScrollRegion()
hegyi@1510
    44
{
hegyi@1510
    45
  double wx1, wy1, wx2, wy2;
hegyi@1510
    46
  Gnome::Canvas::Item* pCanvasItem = root();
hegyi@1510
    47
  pCanvasItem->get_bounds(wx1, wy1, wx2, wy2);
hegyi@1510
    48
  set_scroll_region(wx1, wy1, wx2, wy2);
hegyi@1510
    49
}