** This is part of the CTSim program
** Copyright (c) 1983-2001 Kevin Rosenberg
**
-** $Id: backprojectors.cpp,v 1.28 2001/02/23 02:06:01 kevin Exp $
+** $Id: backprojectors.cpp,v 1.29 2001/03/01 07:30:49 kevin Exp $
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License (version 2) as
yInc = (yMax - yMin) / ny;
m_dFocalLength = proj.focalLength();
+ m_dSourceDetectorLength = proj.sourceDetectorLength();
}
Backproject::~Backproject ()
double dU = (m_dFocalLength + rsin_t) / m_dFocalLength;
double dDetPos = rcos_t / dU;
- // double to scale for imaginary detector that passes through origin
- // of phantom, see Kak-Slaney Figure 3.22. This assumes that the detector is also
- // located focal-length away from the origin.
- dDetPos *= 2;
+ // Scale for imaginary detector that passes through origin of phantom, see Kak-Slaney Figure 3.22.
+ dDetPos *= m_dSourceDetectorLength / m_dFocalLength;
double dPos = dDetPos / detInc; // position along detector array
if (interpType == Backprojector::INTERP_NEAREST) {