1 files changed, 143 insertions, 0 deletions
diff --git a/tests/galaxy/cumulativedistributor.cpp b/tests/galaxy/cumulativedistributor.cpp
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+++ b/tests/galaxy/cumulativedistributor.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd
+** All rights reserved.
+** For any questions to The Qt Company, please use contact form at http://qt.io
+**
+** This file is part of the Qt Data Visualization module.
+**
+** Licensees holding valid commercial license for Qt may use this file in
+** accordance with the Qt License Agreement provided with the Software
+** or, alternatively, in accordance with the terms contained in a written
+** agreement between you and The Qt Company.
+**
+** If you have questions regarding the use of this file, please use
+** contact form at http://qt.io
+**
+****************************************************************************/
+
+/*
+ * Galaxy creation code obtained from http://beltoforion.de/galaxy/galaxy_en.html
+ * Thanks to Ingo Berg, great work.
+ * Licensed under a  Creative Commons Attribution 3.0 License
+ * http://creativecommons.org/licenses/by/3.0/
+ */
+
+#include "cumulativedistributor.h"
+
+#include <QDebug>
+
+CumulativeDistributor::CumulativeDistributor()
+    : m_pDistFun(NULL),
+      m_vM1(),
+      m_vY1(),
+      m_vX1(),
+      m_vM2(),
+      m_vY2(),
+      m_vX2()
+{
+}
+
+CumulativeDistributor::~CumulativeDistributor()
+{
+}
+
+void CumulativeDistributor::setupRealistic(qreal I0, qreal k, qreal a,
+                                           qreal RBulge, qreal min, qreal max,
+                                           int nSteps)
+{
+    m_fMin = min;
+    m_fMax = max;
+    m_nSteps = nSteps;
+
+    m_I0 = I0;
+    m_k  = k;
+    m_a  = a;
+    m_RBulge = RBulge;
+
+    m_pDistFun = &CumulativeDistributor::Intensity;
+
+    // build the distribution function
+    buildCDF(m_nSteps);
+}
+
+void CumulativeDistributor::buildCDF(int nSteps)
+{
+    qreal h = (m_fMax - m_fMin) / nSteps;
+    qreal x = 0, y = 0;
+
+    m_vX1.clear();
+    m_vY1.clear();
+    m_vX2.clear();
+    m_vM1.clear();
+    m_vM1.clear();
+
+    // Simpson rule for integration of the distribution function
+    m_vY1.push_back(0.0);
+    m_vX1.push_back(0.0);
+    for (int i = 0; i < nSteps; i += 2) {
+        x = (i + 2) * h;
+        y += h/3 * ((this->*m_pDistFun)(m_fMin + i*h) + 4*(this->*m_pDistFun)(m_fMin + (i+1)*h) + (this->*m_pDistFun)(m_fMin + (i+2)*h) );
+
+        m_vM1.push_back((y - m_vY1.back()) / (2*h));
+        m_vX1.push_back(x);
+        m_vY1.push_back(y);
+    }
+
+    // normieren
+    for (int i = 0; i < m_vM1.size(); i++) {
+        m_vY1[i] /= m_vY1.back();
+        m_vM1[i] /= m_vY1.back();
+    }
+
+    m_vY2.clear();
+    m_vM2.clear();
+    m_vY2.push_back(0.0);
+
+    qreal p = 0;
+    h = 1.0 / nSteps;
+    for (int i = 1, k = 0; i < nSteps; ++i) {
+        p = (qreal)i * h;
+
+        for (; m_vY1[k+1] <= p; ++k) {
+        }
+
+        y = m_vX1[k] + (p - m_vY1[k]) / m_vM1[k];
+
+        m_vM2.push_back( (y - m_vY2.back()) / h);
+        m_vX2.push_back(p);
+        m_vY2.push_back(y);
+    }
+}
+
+qreal CumulativeDistributor::valFromProp(qreal fVal)
+{
+  if (fVal < 0.0 || fVal > 1.0)
+    throw std::runtime_error("out of range");
+
+  qreal h = 1.0 / m_vY2.size();
+
+  int i = int(fVal / h);
+  qreal remainder = fVal - i*h;
+
+  int min = qMin(m_vY2.size(), m_vM2.size());
+  if (i >= min)
+      i = min - 1;
+
+  return (m_vY2[i] + m_vM2[i] * remainder);
+}
+
+qreal CumulativeDistributor::IntensityBulge(qreal R, qreal I0, qreal k)
+{
+    return I0 * exp(-k * pow(R, 0.25));
+}
+
+qreal CumulativeDistributor::IntensityDisc(qreal R, qreal I0, qreal a)
+{
+  return I0 * exp(-R/a);
+}
+
+qreal CumulativeDistributor::Intensity(qreal x)
+{
+    return (x < m_RBulge) ? IntensityBulge(x, m_I0, m_k) : IntensityDisc(x - m_RBulge, IntensityBulge(m_RBulge, m_I0, m_k), m_a);
+}