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filterselect.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 "filterselect.h"

ChannelSelectBoxFilter::ChannelSelectBoxFilter() : ChannelFilter<unsigned char>()
{
  active = false;
  x0 = y0 = x1 = y1 = 0;
}

ChannelSelectBoxFilter::~ChannelSelectBoxFilter()
{
}

void ChannelSelectBoxFilter::OnMouseEvent(const int button, const int state, int x, int y)
{ 
  bool activity = active;
  if(!activity && button==0 && state==0)
  {
    active = true;
    ChannelFilter<unsigned char>::Normalize(&x,&y);
    x0 = x1 = x;
    y0 = y1 = y;
  }
  if(activity && button==0 && state==1)
  {
    active = false;
    x1 = x;
    y1 = y;
    ChannelFilter<unsigned char>::Normalize(&x0,&y0,&x1,&y1);
    InvertArea(x0,y0,x1,y1);
    OnAction(x0,y0,x1,y1);
  }
}

void ChannelSelectBoxFilter::OnMotionEvent(int x, int y)
{
  ChannelFilter<unsigned char>::Normalize(&x,&y);
  if(active)
  {
    InvertArea(x0,y0,x1,y1,x,y);
    x1 = x;
    y1 = y;
  }
}

unsigned char ChannelSelectBoxFilter::Get(const int x, const int y)
{
  return(active&&(x>=x0&&x<=x1||x>=x1&&x<=x0)&&(y>=y0&&y<=y1||y>=y1&&y<=y0)
    ? InvertPixel(ChannelFilter<unsigned char>::Get(x,y)) : ChannelFilter<unsigned char>::Get(x,y));
}

void ChannelSelectBoxFilter::Set(const int x, const int y, const unsigned char val)
{
  if(active&&(x>=x0&&x<=x1||x>=x1&&x<=x0)&&(y>=y0&&y<=y1||y>=y1&&y<=y0))
    ChannelFilter<unsigned char>::Set(x,y,InvertPixel(val));
  else
    ChannelFilter<unsigned char>::Set(x,y,val);;
}

inline unsigned char ChannelSelectBoxFilter::InvertPixel(unsigned char val)
{
  return(255 - val);
}

void ChannelSelectBoxFilter::InvertArea(int x0, int y0, int x1, int y1)
{
  ChannelFilter<unsigned char>::Normalize(&x0,&y0,&x1,&y1);
  for(int x=x0;x<x1;x++)
    for(int y=y0;y<y1;y++)
      ChannelFilter<unsigned char>::Set(x,y,InvertPixel(ChannelFilter<unsigned char>::Get(x,y)));

}
void ChannelSelectBoxFilter::InvertArea(int x0, int y0, int x1a, int y1a, int x1b, int y1b)
{
  InvertArea(x0,y1a,x1a,y1b);
  InvertArea(x1a,y0,x1b,y1b);
}

void ChannelSelectBoxFilter::ResetChannel()
{
  if(active)
  {
    InvertArea(x0,y0,x1,y1);
    active = false;
  }
  ChannelFilter<unsigned char>::ResetChannel();
}

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