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/* **************************************************************************
qgslinearminmaxenhancementwithclip.cpp - description
-------------------
begin : Fri Nov 16 2007
copyright : (C) 2007 by Peter J. Ersts
email : ersts@amnh.org
****************************************************************************/
/* **************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************/
#include "qgslinearminmaxenhancementwithclip.h"
QgsLinearMinMaxEnhancementWithClip::QgsLinearMinMaxEnhancementWithClip( QgsContrastEnhancement::QgsRasterDataType theQgsRasterDataType, double theMinimumValue, double theMaximumValue ) : QgsContrastEnhancementFunction( theQgsRasterDataType, theMinimumValue, theMaximumValue )
{
}
int QgsLinearMinMaxEnhancementWithClip::enhance( double theValue )
{
if ( theValue < mMinimumValue || theValue > mMaximumValue )
{
return -1;
}
int myStretchedValue = static_cast<int>((( theValue - mMinimumValue ) / ( mMinimumMaximumRange ) ) * 255.0 );
if ( myStretchedValue < 0 )
{
return 0;
}
else if ( myStretchedValue > 255 )
{
return 255;
}
return myStretchedValue;
}
bool QgsLinearMinMaxEnhancementWithClip::isValueInDisplayableRange( double theValue )
{
if ( theValue < mMinimumValue || theValue > mMaximumValue )
{
return false;
}
return true;
}
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