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/*
-----------------------------------------------------------------------
Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
2014-2015, CWI, Amsterdam
Contact: astra@astra-toolbox.com
Website: http://sf.net/projects/astra-toolbox
This file is part of the ASTRA Toolbox.
The ASTRA Toolbox 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.
The ASTRA Toolbox 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 for more details.
You should have received a copy of the GNU General Public License
along with the ASTRA Toolbox. If not, see <http://www.gnu.org/licenses/>.
-----------------------------------------------------------------------
$Id$
*/
#include "astra/GeometryUtil2D.h"
#include <cmath>
namespace astra {
SParProjection* genParProjections(unsigned int iProjAngles,
unsigned int iProjDets,
double fDetSize,
const float *pfAngles,
const float *pfExtraOffsets)
{
SParProjection base;
base.fRayX = 0.0f;
base.fRayY = 1.0f;
base.fDetSX = iProjDets * fDetSize * -0.5f;
base.fDetSY = 0.0f;
base.fDetUX = fDetSize;
base.fDetUY = 0.0f;
SParProjection* p = new SParProjection[iProjAngles];
#define ROTATE0(name,i,alpha) do { p[i].f##name##X = base.f##name##X * cos(alpha) - base.f##name##Y * sin(alpha); p[i].f##name##Y = base.f##name##X * sin(alpha) + base.f##name##Y * cos(alpha); } while(0)
for (unsigned int i = 0; i < iProjAngles; ++i) {
if (pfExtraOffsets) {
// TODO
}
ROTATE0(Ray, i, pfAngles[i]);
ROTATE0(DetS, i, pfAngles[i]);
ROTATE0(DetU, i, pfAngles[i]);
if (pfExtraOffsets) {
float d = pfExtraOffsets[i];
p[i].fDetSX -= d * p[i].fDetUX;
p[i].fDetSY -= d * p[i].fDetUY;
}
}
#undef ROTATE0
return p;
}
SFanProjection* genFanProjections(unsigned int iProjAngles,
unsigned int iProjDets,
double fOriginSource, double fOriginDetector,
double fDetSize,
const float *pfAngles)
// const float *pfExtraOffsets)
{
SFanProjection *pProjs = new SFanProjection[iProjAngles];
float fSrcX0 = 0.0f;
float fSrcY0 = -fOriginSource;
float fDetUX0 = fDetSize;
float fDetUY0 = 0.0f;
float fDetSX0 = iProjDets * fDetUX0 / -2.0f;
float fDetSY0 = fOriginDetector;
#define ROTATE0(name,i,alpha) do { pProjs[i].f##name##X = f##name##X0 * cos(alpha) - f##name##Y0 * sin(alpha); pProjs[i].f##name##Y = f##name##X0 * sin(alpha) + f##name##Y0 * cos(alpha); } while(0)
for (unsigned int i = 0; i < iProjAngles; ++i) {
ROTATE0(Src, i, pfAngles[i]);
ROTATE0(DetS, i, pfAngles[i]);
ROTATE0(DetU, i, pfAngles[i]);
}
#undef ROTATE0
return pProjs;
}
// Convert a SParProjection back into its set of "standard" circular parallel
// beam parameters. This is always possible.
bool getParParameters(const SParProjection &proj, unsigned int iProjDets, float &fAngle, float &fDetSize, float &fOffset)
{
// Take part of DetU orthogonal to Ray
double ux = proj.fDetUX;
double uy = proj.fDetUY;
double t = (ux * proj.fRayX + uy * proj.fRayY) / (proj.fRayX * proj.fRayX + proj.fRayY * proj.fRayY);
ux -= t * proj.fRayX;
uy -= t * proj.fRayY;
double angle = atan2(uy, ux);
fAngle = (float)angle;
double norm2 = uy * uy + ux * ux;
fDetSize = (float)sqrt(norm2);
// CHECKME: SIGNS?
fOffset = (float)(-0.5*iProjDets - (proj.fDetSY*uy + proj.fDetSX*ux) / norm2);
return true;
}
// Convert a SFanProjection back into its set of "standard" circular fan beam
// parameters. This will return false if it can not be represented in this way.
bool getFanParameters(const SFanProjection &proj, unsigned int iProjDets, float &fAngle, float &fOriginSource, float &fOriginDetector, float &fDetSize, float &fOffset)
{
// angle
// det size
// offset
// origin-source
// origin-detector
// Need to check if line source-origin is orthogonal to vector ux,uy
// (including the case source==origin)
// (equivalent: source and origin project to same point on detector)
double dp = proj.fSrcX * proj.fDetUX + proj.fSrcY * proj.fDetUY;
double rel = (proj.fSrcX*proj.fSrcX + proj.fSrcY*proj.fSrcY) * (proj.fDetUX*proj.fDetUX + proj.fDetUY*proj.fDetUY);
rel = sqrt(rel);
if (std::abs(dp) > rel * 0.0001)
return false;
fOriginSource = sqrt(proj.fSrcX*proj.fSrcX + proj.fSrcY*proj.fSrcY);
fDetSize = sqrt(proj.fDetUX*proj.fDetUX + proj.fDetUY*proj.fDetUY);
// project origin on detector line ( == project source on detector line)
double t = (- proj.fDetSX) * proj.fDetUX + (- proj.fDetSY) * proj.fDetUY;
fOffset = (float)t - 0.5*iProjDets;
// TODO: CHECKME
fOriginDetector = sqrt((proj.fDetSX + t * proj.fDetUX)*(proj.fDetSX + t * proj.fDetUX) + (proj.fDetSY + t * proj.fDetUY)*(proj.fDetSY + t * proj.fDetUY));
//float fAngle = atan2(proj.fDetSX + t * proj.fDetUX - proj.fSrcX, proj.fDetSY + t * proj.fDetUY); // TODO: Fix order + sign
fAngle = atan2(proj.fDetUY, proj.fDetUX); // TODO: Check order + sign
return true;
}
}
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