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filterfloodfill.cpp

/**********************************************************************************
* Copyright (c) 2003, Christoph Rueegg <opendev@cdrnet.ch> and Matthias Bader     *
* Partially based on ideas of Tim Weyrich <weyrich@inf.ethz.ch>                   *
* and/or the Swiss Federal Institute of Technology http://www.ethz.ch             *
* All rights reserved.                                                            *
*                                                                                 *
* Project Website: http://www.cdrnet.net/projects/painter/                        *
*                                                                                 *
* Redistribution and use in source and binary forms, with or without modification,*
* are permitted provided that the following conditions are met:                   *
*                                                                                 *
* 1. Redistributions of source code must retain the above copyright notice,       *
* this list of conditions and the following disclaimer.                           *
*                                                                                 *
* 2. Redistributions in binary form must reproduce the above copyright notice,    *
* this list of conditions and the following disclaimer in the documentation       *
* and/or other materials provided with the distribution.                          *
*                                                                                 *
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"     *
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE       *
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE      *
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE        *
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR             *
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF            *
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS        *
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN         *
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)         *
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF          *
* THE POSSIBILITY OF SUCH DAMAGE.                                                 *
**********************************************************************************/

#include "filterfloodfill.h"
#include "../container/fixedstack.h"
#include <cmath>

FloodFillFilter::FloodFillFilter() : ChannelSelectDotFilter(true)
{
  already = 0;
  tolerance = 25;
  fillcolor = 100;
  x0 = y0 = 0;
}

FloodFillFilter::~FloodFillFilter()
{
  delete already;
}

void FloodFillFilter::OnMouseEvent(const int button, const int state, int x, int y)
{       
  if(button!=0)
  {
    ChannelSelectDotFilter::OnMouseEvent(button, state, x, y);
  }
  ChannelSelectDotFilter::Normalize(&x,&y);
  if(state == 0 && button == 0)
  {
    x0 = x;
    y0 = y;
  }
  if(state == 1 && button == 0)
  {
    x0 = x-x0;
    y0 = y-y0;
    x = x-x0;
    y = y-y0;
    tolerance = (char)(abs(x0*200.0/ChannelSelectDotFilter::GetWidth()));
    if(tolerance < 2)
      tolerance = 20;
    fillcolor = ChannelSelectDotFilter::GetSelectedColor();
    unsigned char color = ChannelSelectDotFilter::Get(x,y);
    unsigned char low   = tolerance>color ? 0 : color-tolerance;
    unsigned char high  = tolerance>(255-color) ? 255 : color+tolerance;
    unsigned char currentcolor = 0;
    already = new Channel<bool>(ChannelSelectDotFilter::GetHeight(),ChannelSelectDotFilter::GetWidth());
    for(int x1=0;x1<already->GetWidth();x1++)
      for(int y1=0;y1<already->GetHeight();y1++)
        already->Set(x1,y1,false);
    FixedStack* stack = new FixedStack(already->GetWidth()*already->GetHeight());
    already->Set(x,y,true);
    stack->Push(x,y);
    while(stack->Pop(&x,&y))
    {
      currentcolor = ChannelSelectDotFilter::Get(x,y);
      if(currentcolor >= low && currentcolor <= high) 
      {
        ChannelSelectDotFilter::Set(x,y,fillcolor);
        if(x>0 && !already->Get(x-1,y))
        {
          stack->Push(x-1,y);
          already->Set(x-1,y,true);
        }
        if(x<ChannelSelectDotFilter::GetWidth()-1 && !already->Get(x+1,y))
        {
          stack->Push(x+1,y);
          already->Set(x+1,y,true);
        }
        if(y>0 && !already->Get(x,y-1))
        {
          stack->Push(x,y-1);
          already->Set(x,y-1,true);
        }
        if(y<ChannelSelectDotFilter::GetHeight()-1 && !already->Get(x,y+1))
        {
          stack->Push(x,y+1);
          already->Set(x,y+1,true);
        }
        already->Set(x,y,true);
      }
    }
    delete stack;
    delete already;
    already = 0;
  }
}

ChannelFilter<unsigned char>* FloodFillFilter::EmptyClone()
{
  FloodFillFilter *copy = new FloodFillFilter();
  copy->SetSubChannel(ChannelSelectDotFilter::GetSubChannel());
  return(copy);
}

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