** This is part of the CTSim program
** Copyright (c) 1983-2001 Kevin Rosenberg
**
-** $Id: scanner.cpp,v 1.30 2001/02/08 06:25:07 kevin Exp $
+** $Id: scanner.cpp,v 1.31 2001/02/20 17:44:14 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
m_rotLen = rot_anglen;
m_rotInc = m_rotLen / m_nView;
if (m_idGeometry == GEOMETRY_PARALLEL) {
+ m_dFanBeamAngle = 0;
m_detLen = m_dScanDiameter;
m_detInc = m_detLen / m_nDet;
- if (m_nDet % 2 == 0) // Adjust for Even number of detectors
- m_detInc = m_detLen / (m_nDet - 1); // center detector = (nDet/2)-1
-
- m_dFanBeamAngle = 0;
+ double dDetectorArrayEndOffset = 0;
+ // For even number of detectors, make detInc slightly larger so that center lies
+ // at nDet/2. Also, extend detector array by one detInc so that all of the phantom is scanned
+ if (m_nDet % 2 == 0) { // Adjust for Even number of detectors
+ m_detInc = m_detLen / (m_nDet - 1); // center detector = (nDet/2)
+ dDetectorArrayEndOffset = m_detInc;
+ }
+
double dHalfDetLen = m_detLen / 2;
m_initPos.xs1 = m_dXCenter - dHalfDetLen;
m_initPos.ys1 = m_dYCenter + m_dFocalLength;
- m_initPos.xs2 = m_dXCenter + dHalfDetLen;
+ m_initPos.xs2 = m_dXCenter + dHalfDetLen + dDetectorArrayEndOffset;
m_initPos.ys2 = m_dYCenter + m_dFocalLength;
m_initPos.xd1 = m_dXCenter - dHalfDetLen;
m_initPos.yd1 = m_dYCenter - m_dFocalLength;
- m_initPos.xd2 = m_dXCenter + dHalfDetLen;
+ m_initPos.xd2 = m_dXCenter + dHalfDetLen + dDetectorArrayEndOffset;
m_initPos.yd2 = m_dYCenter - m_dFocalLength;
m_initPos.angle = 0.0;
} else if (m_idGeometry == GEOMETRY_EQUILINEAR) {
m_detLen = dHalfDetLen * 2;
m_detInc = m_detLen / m_nDet;
- if (m_nDet % 2 == 0) // Adjust for Even number of detectors
- m_detInc = m_detLen / (m_nDet - 1); // center detector = (nDet/2)-1
+ double dDetectorArrayEndOffset = 0;
+ if (m_nDet % 2 == 0) { // Adjust for Even number of detectors
+ m_detInc = m_detLen / (m_nDet - 1); // center detector = (nDet/2)
+ dDetectorArrayEndOffset = m_detInc;
+ }
m_dFanBeamAngle = dAngle * 2;
m_initPos.angle = 0.0;
m_initPos.ys2 = m_dYCenter + m_dFocalLength;
m_initPos.xd1 = m_dXCenter - dHalfDetLen;
m_initPos.yd1 = m_dYCenter - m_dFocalLength;
- m_initPos.xd2 = m_dXCenter + dHalfDetLen;
+ m_initPos.xd2 = m_dXCenter + dHalfDetLen + dDetectorArrayEndOffset;
m_initPos.yd2 = m_dYCenter - m_dFocalLength;
m_initPos.angle = 0.0;
} else if (m_idGeometry == GEOMETRY_EQUIANGULAR) {
m_detLen = 2 * dAngle;
m_detInc = m_detLen / m_nDet;
- if (m_nDet % 2 == 0) // Adjust for Even number of detectors
- m_detInc = m_detLen / (m_nDet - 1); // center detector = (nDet/2)-1
- m_dAngularDetIncrement = m_detInc * 2; // Angular Position 2x gamma angle
- m_dAngularDetLen = m_detLen * 2;
+ double dDetectorArrayEndOffset = 0;
+ if (m_nDet % 2 == 0) { // Adjust for Even number of detectors
+ m_detInc = m_detLen / (m_nDet - 1); // center detector = (nDet/2)
+ dDetectorArrayEndOffset = m_detInc;
+ }
+ m_dAngularDetIncrement = 2 * m_detInc; // Angular Position 2x gamma angle
+ m_dAngularDetLen = 2 * m_detLen + 2 * dDetectorArrayEndOffset;
m_initPos.dAngularDet = -m_dAngularDetLen / 2;
m_dFanBeamAngle = dAngle * 2;