Problem mit DrawingArea in Gtkmm

[wild_wing]

Hallo, ich programmiere gerade ein kleines Paintprogramm und nutze dazu die Drawingarea. Ich lade dann ein Bild und lasse es anzeigen. Nun möchte ich einen Breich markieren/auswählen (so eine art Maske), aber das funktioniert nicht so richtig. Kann mir da jemand helfen.

hier der Code der Klasse:

#include <iostream>
#include <sstream>
#include <gtkmm/image.h>
#include "Imagebox.h"

Imagebox::Imagebox(int xSize, int ySize)
{
  Glib::RefPtr<Gdk::Colormap> colormap = get_default_colormap();

  black_ = Gdk::Color("black");
  white_ = Gdk::Color("white");
  grey_ = Gdk::Color("grey");
  red_ = Gdk::Color("red");
  blue_ = Gdk::Color("blue");

  colormap->alloc_color(black_);
  colormap->alloc_color(white_);
  colormap->alloc_color(grey_);
  colormap->alloc_color(red_);
  colormap->alloc_color(blue_);

  x_Size = xSize; y_Size = ySize;
  lMouseClicked = false;
  mMouseClicked = false;
  rMouseClicked = false;
  drawing = false;

  set_events( Gdk::POINTER_MOTION_MASK | Gdk::BUTTON_PRESS_MASK | Gdk::BUTTON_RELEASE_MASK );

  signal_motion_notify_event().connect(sigc::mem_fun( *this, &Imagebox::on_area_motion_notify_event) );
  signal_button_press_event().connect(sigc::mem_fun( *this, &Imagebox::on_area_button_press_event) );
  signal_button_release_event().connect(sigc::mem_fun( *this, &Imagebox::on_area_button_release_event) );

  buff = NULL;
}

Imagebox::~Imagebox()
{

}

void Imagebox::LoadPic(const std::string filename, unsigned char *picBuffer)
{
  FILE  *stream;

  if ( (stream  = fopen( (char*)filename.c_str() , "rb" )) == NULL )
    {
      std::cout<<"error while open file "<<filename<<std::endl;
    }
  else
   {
     // read the data from RAW input file
     fread( picBuffer, 1392 * 1040, 1, stream );
     fclose(stream);
   }
}

bool Imagebox::on_area_motion_notify_event(GdkEventMotion* event)
{
  std::ostringstream tmp;

  if (event)
    {

//      hruler->property_position().set_value(event->x);
//      vruler->property_position().set_value(event->y);
      tmp<<event->x<<","<<event->y;
      label_xypos->set_text( tmp.str() );

      if ( lMouseClicked )
        {
          switch ( *tool )
          {
            case 1:
            {
              gc02->set_line_attributes(2,Gdk::LINE_ON_OFF_DASH,Gdk::CAP_NOT_LAST,Gdk::JOIN_MITER);
//            gc01->set_line_attributes(2,Gdk::LINE_SOLID,Gdk::CAP_NOT_LAST,Gdk::JOIN_MITER);
              xpos = (int)event->x;
              ypos = (int)event->y;
              if (lastx != xpos || lasty != ypos)
                {
                  // erase old rectangle
                  gc02->set_foreground(white_);
                  window->draw_rectangle(gc02,false,startx,starty,lastx-startx,lasty-starty);
                  //  window->draw_image(gc01,image,xpos-startx,ypos-starty,xpos-startx,ypos-starty);
                  // draw new rectangle
                  gc02->set_foreground(red_);
                  window->draw_rectangle(gc02,false,startx,starty,xpos-startx,ypos-starty);
//                  image = window->get_image (startx+1,starty+1,xpos-startx-1,ypos-starty-1);

                  lastx = xpos;
                  lasty = ypos;
                }
              break;
            }
            case 2:
            {
              gc02->set_line_attributes(2,Gdk::LINE_SOLID,Gdk::CAP_NOT_LAST,Gdk::JOIN_MITER);
              xpos = (int)event->x;
              ypos = (int)event->y;
              gc02->set_foreground(red_);
              draw_brush(xpos,ypos);
              break;
            }
            default: break;
          }// switch
        }
      else
        {
        }
      if ( mMouseClicked )
        {
        }
      if ( rMouseClicked )
        {
        }
    }

  return true;
}

bool Imagebox::on_area_button_press_event(GdkEventButton* event)
{
  if ( event->type == GDK_BUTTON_PRESS )
    {
      /* linke Maustaste */
      if ( event->button == 1 )
        {
          lMouseClicked = true;
          startx = (int)event->x;
          starty  = (int)event->y;
          lastx = startx;
          lasty = starty;
          drawing = true;
        }
      /* mittlere Maustaste */
      if ( event->button == 2 )
        {
          mMouseClicked = true;
        }
      /* rechte Maustaste */
      if ( event->button == 3 )
        {
          rMouseClicked = true;
        }
    }
  return false;
}

bool Imagebox::on_area_button_release_event(GdkEventButton* event)
{
  if ( event->type == GDK_BUTTON_RELEASE )
    {
      /* linke Maustaste */
      if ( event->button == 1 )
        {
          lMouseClicked = false;
          drawing = true;

//        image = window->get_image (startx+1,starty+1,xpos-1,ypos-1);
          window->draw_image(gc01,image,startx+1,starty+1,startx+1,starty+1,(xpos-1)-(startx+1),(ypos-1)-(starty+1));
/*
          std::cout<<"x"<<xpos<<std::endl;
          std::cout<<"y"<<ypos<<std::endl;
          std::cout<<"lx"<<lastx<<std::endl;
          std::cout<<"ly"<<lasty<<std::endl;
          std::cout<<"sx"<<startx<<std::endl;
          std::cout<<"sy"<<starty<<std::endl;
*/
        }
      /* mittlere Maustaste */
      if ( event->button == 2 )
        {
          mMouseClicked = false;
        }
      /* rechte Maustaste */
      if ( event->button == 3 )
        {
          rMouseClicked = false;
        }
    }
  return false;
}

void Imagebox::on_realize()
{
  Gtk::DrawingArea::on_realize();

  window = get_window();

  gc01 = Gdk::GC::create(window);
  gc02 = Gdk::GC::create(window);

  window->resize( x_Size, y_Size );
  window->set_background(white_);
  window->clear();
}

bool Imagebox::on_expose_event(GdkEventExpose* event)
{
  int winx, winy, winw,winh,wind;
  window = get_window();

  window->get_geometry(winx,winy,winw,winh,wind);

  image = window->get_image (0,0,x_Size,y_Size);

  if ( buff != NULL)
    {
      window->draw_gray_image(gc01,0,0,w,h,Gdk::RGB_DITHER_NONE,buff,1*w);
    }

//  window->draw_image(gc01,image,0,0,0,0,image->get_width(),image->get_height());

  return true;
}

void Imagebox::draw_brush(gdouble x, gdouble y)
{
  window->draw_rectangle(gc02,true,(int)x-5,(int)y-5,10,10);
}

void Imagebox::push_picture(unsigned char *buffer, unsigned int nWidth, unsigned int nHeight)
{
  buff = buffer;
  w = nWidth;
  h = nHeight;
  window->draw_gray_image(gc01,0,0,nWidth,nHeight,Gdk::RGB_DITHER_NONE,buffer,1*nWidth);
}