ResInsight/Fwk/VizFwk/LibRender/cvfScalarMapperContinuousLog.cpp
2019-05-28 15:58:49 +02:00

124 lines
4.4 KiB
C++

//##################################################################################################
//
// Custom Visualization Core library
// Copyright (C) 2011-2013 Ceetron AS
//
// This library may be used under the terms of either the GNU General Public License or
// the GNU Lesser General Public License as follows:
//
// GNU General Public License Usage
// This library 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 3 of the License, or
// (at your option) any later version.
//
// This library is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.
//
// See the GNU General Public License at <<http://www.gnu.org/licenses/gpl.html>>
// for more details.
//
// GNU Lesser General Public License Usage
// This library is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation; either version 2.1 of the License, or
// (at your option) any later version.
//
// This library is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.
//
// See the GNU Lesser General Public License at <<http://www.gnu.org/licenses/lgpl-2.1.html>>
// for more details.
//
//##################################################################################################
#include "cvfScalarMapperContinuousLog.h"
#include "cvfMath.h"
#include "cvfTextureImage.h"
#include <cmath>
#include <limits>
namespace cvf {
//==================================================================================================
///
/// \class cvf::ScalarMapperContinuousLog
/// \ingroup Render
///
/// Maps scalar values to texture coordinates/colors using continuous logarithmic mapping
/// Configured by specifying a number of level colors and a min/max range.
//==================================================================================================
ScalarMapperContinuousLog::ScalarMapperContinuousLog()
: m_logRange(0.0)
, m_logRangeMin(0.0)
, m_hasNegativeRange(false)
{
}
//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
double ScalarMapperContinuousLog::normalizedValue(double scalarValue) const
{
if (m_hasNegativeRange) scalarValue = -1.0*scalarValue;
double logValue;
if (scalarValue <= 0) logValue = std::numeric_limits<double>::min_exponent10;
else logValue = log10(scalarValue);
if (m_logRange != 0)
{
return cvf::Math::clamp((logValue - m_logRangeMin)/m_logRange, 0.0, 1.0);
}
else
{
return 0;
}
}
//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
double ScalarMapperContinuousLog::domainValue(double normalizedPosition) const
{
double logValue = normalizedPosition*m_logRange + m_logRangeMin;
double domainVal = pow(10, logValue);
if (m_hasNegativeRange)
domainVal *= -1.0;
return domainVal;
}
//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void ScalarMapperContinuousLog::rangeUpdated()
{
m_hasNegativeRange = false;
double transformedRangeMax = m_rangeMax;
double transformedRangeMin = m_rangeMin;
if ( m_rangeMax <= 0 && m_rangeMin <= 0)
{
m_hasNegativeRange = true;
transformedRangeMax = -1.0*transformedRangeMax;
transformedRangeMin = -1.0*transformedRangeMin;
}
double logRangeMax = (transformedRangeMax > 0) ? log10(transformedRangeMax): std::numeric_limits<double>::min_exponent10;
m_logRangeMin = (transformedRangeMin > 0) ? log10(transformedRangeMin): std::numeric_limits<double>::min_exponent10;
m_logRange = logRangeMax - m_logRangeMin;
}
} // namespace cvf