1 /*****************************************************************************
5 ** Purpose: Routines for phantom objects
6 ** Progammer: Kevin Rosenberg
7 ** Date Started: Aug 1984
9 ** This is part of the CTSim program
10 ** Copyright (C) 1983-2000 Kevin Rosenberg
12 ** $Id: phantom.cpp,v 1.26 2001/01/02 16:02:13 kevin Exp $
14 ** This program is free software; you can redistribute it and/or modify
15 ** it under the terms of the GNU General Public License (version 2) as
16 ** published by the Free Software Foundation.
18 ** This program is distributed in the hope that it will be useful,
19 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
20 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 ** GNU General Public License for more details.
23 ** You should have received a copy of the GNU General Public License
24 ** along with this program; if not, write to the Free Software
25 ** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 ******************************************************************************/
30 const int PhantomElement::POINTS_PER_CIRCLE = 360;
31 const double PhantomElement::SCALE_PELEM_EXTENT=0.005; // increase pelem limits by 0.5%
33 const int Phantom::PHM_INVALID = -1;
34 const int Phantom::PHM_HERMAN = 0;
35 const int Phantom::PHM_B_HERMAN = 1;
36 const int Phantom::PHM_SHEPP_LOGAN = 2;
37 const int Phantom::PHM_B_SHEPP_LOGAN = 3;
38 const int Phantom::PHM_UNITPULSE = 4;
40 const char* Phantom::s_aszPhantomName[] =
49 const char* Phantom::s_aszPhantomTitle[] =
52 {"Herman Head (Bordered)"},
54 {"Shepp-Logan (Bordered)"},
58 const int Phantom::s_iPhantomCount = sizeof(s_aszPhantomName) / sizeof(const char*);
61 // CLASS IDENTIFICATION
71 Phantom::Phantom (const char* const phmName)
74 createFromPhantom (phmName);
86 m_composition = P_PELEMS;
93 for (PElemIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
100 Phantom::convertPhantomIDToName (int phmID)
102 static const char *name = "";
104 if (phmID >= 0 && phmID < s_iPhantomCount)
105 return (s_aszPhantomName[phmID]);
111 Phantom::convertPhantomIDToTitle (int phmID)
113 static const char *title = "";
115 if (phmID >= 0 && phmID < s_iPhantomCount)
116 return (s_aszPhantomName[phmID]);
122 Phantom::convertNameToPhantomID (const char* const phmName)
124 int id = PHM_INVALID;
126 for (int i = 0; i < s_iPhantomCount; i++)
127 if (strcasecmp (phmName, s_aszPhantomName[i]) == 0) {
137 Phantom::createFromPhantom (const char* const phmName)
139 int phmid = convertNameToPhantomID (phmName);
140 if (phmid == PHM_INVALID) {
142 m_failMessage = "Invalid phantom name ";
143 m_failMessage += phmName;
148 createFromPhantom (phmid);
153 Phantom::createFromPhantom (const int phmid)
161 addStdHermanBordered();
163 case PHM_SHEPP_LOGAN:
166 case PHM_B_SHEPP_LOGAN:
167 addStdSheppLoganBordered();
170 m_composition = P_UNIT_PULSE;
171 addPElem ("rectangle", 0., 0., 100., 100., 0., 0.); // outline
172 addPElem ("ellipse", 0., 0., 1., 1., 0., 1.); // pulse
176 m_failMessage = "Illegal phantom id ";
177 m_failMessage += phmid;
187 /* METHOD IDENTIFICATION
188 * createFromFile Add PhantomElements from file
191 * createFromFile (filename)
194 * true if pelem were added
195 * false if an pelem not added
199 Phantom::createFromFile (const char* const fname)
201 bool bGoodFile = true;
204 if ((fp = fopen (fname, "r")) == NULL)
210 double cx, cy, u, v, rot, dens;
213 int status = fscanf (fp, "%79s %lf %lf %lf %lf %lf %lf", pelemtype, &cx, &cy, &u, &v, &rot, &dens);
215 if (status == static_cast<int>(EOF))
217 else if (status != 7) {
218 sys_error (ERR_WARNING, "Insufficient fields reading phantom file %s [Phantom::createFromFile]", fname);
221 addPElem (pelemtype, cx, cy, u, v, rot, dens);
230 Phantom::fileWrite (const char* const fname)
232 fstream file (fname, ios::out);
235 printDefinitions (file);
236 return ! file.fail();
243 * addPElem (type, cx, cy, u, v, rot, atten)
244 * char *type type of pelem (box, ellipse, etc)
245 * double cx, cy pelem center
246 * double u,v pelem size
247 * double rot rotation angle of pelem (in degrees)
248 * double atten x-ray attenuation cooefficient
252 Phantom::addPElem (const char *type, const double cx, const double cy, const double u, const double v, const double rot, const double atten)
254 PhantomElement *pelem = new PhantomElement (type, cx, cy, u, v, rot, atten);
256 m_listPElem.push_front (pelem);
258 // update phantom limits
259 if (m_xmin > pelem->xmin()) m_xmin = pelem->xmin();
260 if (m_xmax < pelem->xmax()) m_xmax = pelem->xmax();
261 if (m_ymin > pelem->ymin()) m_ymin = pelem->ymin();
262 if (m_ymax < pelem->ymax()) m_ymax = pelem->ymax();
264 if (m_diameter < pelem->diameter())
265 m_diameter = pelem->diameter();
267 // m_diameter = lineLength(m_xmin, m_ymin, m_xmax, m_ymax);
273 /*----------------------------------------------------------------------*/
274 /* Input-Output Routines */
275 /*----------------------------------------------------------------------*/
279 * print Print vertices of Phantom pelems
286 Phantom::print (std::ostream& os) const
288 os << "Number of PElements: " << m_nPElem << "\n";
289 os << "Limits: xmin=" << m_xmin << ", ymin=" << m_ymin << ", xmax=" << m_xmax << ", ymax=" << m_ymax << "\n";
291 for (PElemConstIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
292 const PhantomElement& rPE = **i;
293 os << "PhantomElement: nPoints=" << rPE.nOutlinePoints();
294 os << ", atten=" << rPE.atten() << " rot=" << convertRadiansToDegrees (rPE.rot()) << "\n";
295 os << "xmin=" << rPE.xmin() << ", ymin=" << rPE.ymin() << ", xmax=" << rPE.xmax() << ", ymax=" << rPE.ymax() << "\n";
298 for (int i = 0; i < rPE.nOutlinePoints(); i++)
299 os << rPE.xOutline()[i] << "," << rPE.yOutline()[i] << "\n";
303 Phantom::print (std::ostringstream& os) const
305 os << "Number of PElements: " << m_nPElem << "\n";
306 os << "Limits: xmin=" << m_xmin << ", ymin=" << m_ymin << ", xmax=" << m_xmax << ", ymax=" << m_ymax << "\n";
308 for (PElemConstIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
309 const PhantomElement& rPE = **i;
310 os << "PhantomElement: nPoints=" << rPE.nOutlinePoints();
311 os << ", atten=" << rPE.atten() << " rot=" << convertRadiansToDegrees (rPE.rot()) << "\n";
312 os << "xmin=" << rPE.xmin() << ", ymin=" << rPE.ymin() << ", xmax=" << rPE.xmax() << ", ymax=" << rPE.ymax() << "\n";
315 for (int i = 0; i < rPE.nOutlinePoints(); i++)
316 os << rPE.xOutline()[i] << "," << rPE.yOutline()[i] << "\n";
321 Phantom::printDefinitions (std::ostream& os) const
323 for (PElemConstIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
324 const PhantomElement& rPE = **i;
325 rPE.printDefinition (os);
330 Phantom::printDefinitions (std::ostringstream& os) const
332 for (PElemConstIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
333 const PhantomElement& rPE = **i;
334 rPE.printDefinition (os);
340 * show Show vector outline of Phantom to user
348 Phantom::show () const
350 SGPDriver driverSGP ("Phantom Show");
355 std::cout << "Press return to continue";
360 Phantom::show (SGP& sgp) const
362 double wsize = m_xmax - m_xmin;
363 if ((m_ymax - m_ymin) > wsize)
364 wsize = m_ymax - m_ymin;
366 double halfWindow = wsize / 2;
368 double xcent = m_xmin + (m_xmax - m_xmin) / 2;
369 double ycent = m_ymin + (m_ymax - m_ymin) / 2;
371 sgp.setWindow (xcent - halfWindow, ycent - halfWindow, xcent + halfWindow, ycent + halfWindow);
379 * draw Draw vector outline of Phantom
387 Phantom::draw (SGP& sgp) const
389 for (PElemIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++)
390 sgp.polylineAbs ((*i)->xOutline(), (*i)->yOutline(), (*i)->nOutlinePoints());
396 * addStdSheppLogan Make head phantom of Shepp-Logan
399 * S. W. Rowland, "Computer Implementation of Image Reconstruction
400 * Formulas", in "Image Reconstruction from Projections: Implementation
401 * and Applications", edited by G. T. Herman, 1978.
405 Phantom::addStdSheppLogan ()
407 addPElem ("ellipse", 0.0000, 0.0000, 0.6900, 0.9200, 0.0, 1.00);
408 addPElem ("ellipse", 0.0000, -0.0184, 0.6624, 0.8740, 0.0, -0.98);
409 addPElem ("ellipse", 0.2200, 0.0000, 0.1100, 0.3100, -18.0, -0.02);
410 addPElem ("ellipse", -0.2200, 0.0000, 0.1600, 0.4100, 18.0, -0.02);
411 addPElem ("ellipse", 0.0000, 0.3500, 0.2100, 0.2500, 0.0, 0.01);
412 addPElem ("ellipse", 0.0000, 0.1000, 0.0460, 0.0460, 0.0, 0.01);
413 addPElem ("ellipse", 0.0000, -0.1000, 0.0460, 0.0460, 0.0, 0.01);
414 addPElem ("ellipse", -0.0800, -0.6050, 0.0460, 0.0230, 0.0, 0.01);
415 addPElem ("ellipse", 0.0000, -0.6050, 0.0230, 0.0230, 0.0, 0.01);
416 addPElem ("ellipse", 0.0600, -0.6050, 0.0230, 0.0230, 0.0, 0.01);
417 addPElem ("ellipse", 0.5538, -0.3858, 0.0330, 0.2060, -18.0, 0.03);
421 Phantom::addStdSheppLoganBordered ()
424 addPElem ("rectangle", 0.000, 0.0000, 0.8600, 1.150, 0.0, 0.00);
428 * addStdHerman Standard head phantom of G. T. Herman
431 * G. T. Herman, "Image Reconstructions from Projections: The Fundementals
432 * of Computed Tomography", 1979.
436 Phantom::addStdHerman ()
438 addPElem ("ellipse", 0.000, 1.50, 0.375, 0.3000, 90.00, -0.003);
439 addPElem ("ellipse", 0.675, -0.75, 0.225, 0.1500, 140.00, 0.010);
440 addPElem ("ellipse", 0.750, 1.50, 0.375, 0.2250, 50.00, 0.003);
441 addPElem ("segment", 1.375, -7.50, 1.100, 0.6250, 19.20, -0.204);
442 addPElem ("segment", 1.375, -7.50, 1.100, 4.3200, 19.21, 0.204);
443 addPElem ("segment", 0.000, -2.25, 1.125, 0.3750, 0.00, -0.003);
444 addPElem ("segment", 0.000, -2.25, 1.125, 3.0000, 0.00, 0.003);
445 addPElem ("segment", -1.000, 3.75, 1.000, 0.5000, 135.00, -0.003);
446 addPElem ("segment", -1.000, 3.75, 1.000, 3.0000, 135.00, 0.003);
447 addPElem ("segment", 1.000, 3.75, 1.000, 0.5000, 225.00, -0.003);
448 addPElem ("segment", 1.000, 3.75, 1.000, 3.0000, 225.00, 0.003);
449 addPElem ("triangle", 5.025, 3.75, 1.125, 0.5000, 110.75, 0.206);
450 addPElem ("triangle",-5.025, 3.75, 1.125, 0.9000,-110.75, 0.206);
451 addPElem ("ellipse", 0.000, 0.00, 8.625, 6.4687, 90.00, 0.416);
452 addPElem ("ellipse", 0.000, 0.00, 7.875, 5.7187, 90.00, -0.206);
456 Phantom::addStdHermanBordered ()
459 addPElem ("rectangle", 0.000, 0.00, 10.780, 8.110, 90.00, 0.000);
464 * convertToImagefile Make image array from Phantom
467 * pic_to_imagefile (pic, im, nsample)
468 * Phantom& pic Phantom definitions
469 * ImageFile *im Computed pixel array
470 * int nsample Number of samples along each axis for each pixel
471 * (total samples per pixel = nsample * nsample)
475 Phantom::convertToImagefile (ImageFile& im, const int in_nsample, const int trace) const
477 convertToImagefile (im, in_nsample, trace, 0, im.nx(), true);
481 Phantom::convertToImagefile (ImageFile& im, const int in_nsample, const int trace, const int colStart, const int colCount, bool bStoreAtColumnPos) const
485 if (nx < 2 || ny < 2)
488 int nsample = in_nsample;
492 double dx = m_xmax - m_xmin;
493 double dy = m_ymax - m_ymin;
494 double xcent = m_xmin + dx / 2;
495 double ycent = m_ymin + dy / 2;
496 double phmlen = (dx > dy ? dx : dy);
498 double phmradius = phmlen / 2;
500 double xmin = xcent - phmradius;
501 double xmax = xcent + phmradius;
502 double ymin = ycent - phmradius;
503 double ymax = ycent + phmradius;
505 // Each pixel holds the average of the intensity of the cell with (ix,iy) at the center of the pixel
506 // Set major increments so that the last cell v[nx-1][ny-1] will start at xmax - xinc, ymax - yinc).
507 // Set minor increments so that sample points are centered in cell
509 double xinc = (xmax - xmin) / nx;
510 double yinc = (ymax - ymin) / ny;
512 double kxinc = xinc / nsample; /* interval between samples */
513 double kyinc = yinc / nsample;
514 double kxofs = kxinc / 2; /* offset of 1st point */
515 double kyofs = kyinc / 2;
517 im.setAxisExtent (xmin, xmax, ymin, ymax);
518 im.setAxisIncrement (xinc, yinc);
520 ImageFileArray v = im.getArray();
522 for (int ix = 0; ix < colCount; ix++)
523 for (int iy = 0; iy < ny; iy++) {
525 if (bStoreAtColumnPos)
526 iColStore += colStart;
527 v[iColStore][iy] = 0;
530 double x_start = xmin + (colStart * xinc);
531 for (PElemConstIterator pelem = m_listPElem.begin(); pelem != m_listPElem.end(); pelem++) {
532 const PhantomElement& rPElem = **pelem;
535 for (ix = 0, x = x_start; ix < colCount; ix++, x += xinc) {
537 if (bStoreAtColumnPos)
538 iColStore += colStart;
539 for (iy = 0, y = ymin; iy < ny; iy++, y += yinc) {
540 for (kx = 0, xi = x + kxofs; kx < nsample; kx++, xi += kxinc) {
541 for (ky = 0, yi = y + kyofs; ky < nsample; ky++, yi += kyinc)
542 if (rPElem.isPointInside (xi, yi, PHM_COORD) == TRUE)
543 v[iColStore][iy] += rPElem.atten();
551 double factor = 1.0 / static_cast<double>(nsample * nsample);
554 for (int ix = 0; ix < colCount; ix++) {
556 if (bStoreAtColumnPos)
557 iColStore += colStart;
558 for (int iy = 0; iy < ny; iy++)
559 v[iColStore][iy] *= factor;
564 ////////////////////////////////////////////////////////////////////////////////////////////////////////
565 // CLASS IDENTIFICATION
571 ////////////////////////////////////////////////////////////////////////////////////////////////////////
574 PhantomElement::PhantomElement (const char *type, const double cx, const double cy, const double u, const double v, const double rot, const double atten)
575 : m_cx(cx), m_cy(cy), m_u(u), m_v(v), m_atten(atten), m_nPoints(0), m_xOutline(0), m_yOutline(0)
577 m_rot = convertDegreesToRadians (rot); // convert angle to radians
579 m_type = convertNameToType (type);
581 makeTransformMatrices (); // calc transform matrices between phantom and normalized phantomelement
582 makeVectorOutline (); // calculate vector outline of pelem
584 // Find maximum diameter of Object
586 for (int i = 0; i < m_nPoints; i++) {
587 double r2 = (m_xOutline[i] * m_xOutline[i]) + (m_yOutline[i] * m_yOutline[i]);
591 m_diameter = 2 * sqrt( r2Max );
593 m_rectLimits[0] = m_xmin; m_rectLimits[1] = m_ymin;
594 m_rectLimits[2] = m_xmax; m_rectLimits[3] = m_ymax;
599 PhantomElement::~PhantomElement ()
606 PhantomElement::printDefinition (std::ostream& os) const
608 os << convertTypeToName (m_type) << " " << m_cx << " " << m_cy << " " << m_u << " "
609 << m_v << " " << convertRadiansToDegrees (m_rot) << " " << m_atten << "\n";
613 PhantomElement::printDefinition (std::ostringstream& os) const
615 os << convertTypeToName (m_type) << " " << m_cx << " " << m_cy << " " << m_u << " "
616 << m_v << " " << convertRadiansToDegrees (m_rot) << " " << m_atten << "\n";
620 PhantomElement::convertNameToType (const char* const typeName)
622 PhmElemType type = PELEM_INVALID;
624 if (strcasecmp (typeName, "rectangle") == 0)
625 type = PELEM_RECTANGLE;
626 else if (strcasecmp (typeName, "triangle") == 0)
627 type = PELEM_TRIANGLE;
628 else if (strcasecmp (typeName, "ellipse") == 0)
629 type = PELEM_ELLIPSE;
630 else if (strcasecmp (typeName, "sector") == 0)
632 else if (strcasecmp (typeName, "segment") == 0)
633 type = PELEM_SEGMENT;
635 sys_error (ERR_WARNING, "Unknown PhantomElement type %s [PhantomElement::PhantomElement]", type);
641 PhantomElement::convertTypeToName (PhmElemType iType)
643 static char* pszType = "Unknown";
645 if (iType == PELEM_RECTANGLE)
646 pszType = "rectangle";
647 else if (iType == PELEM_TRIANGLE)
648 pszType = "triangle";
649 else if (iType == PELEM_ELLIPSE)
651 else if (iType == PELEM_SECTOR)
653 else if (iType == PELEM_SEGMENT)
661 PhantomElement::makeTransformMatrices ()
665 // To map normalized Pelem coords to world Phantom
668 // translate by (cx, cy)
670 scale_mtx2 (m_xformObjToPhm, m_u, m_v);
671 rot_mtx2 (temp, m_rot);
672 mult_mtx2 (m_xformObjToPhm, temp, m_xformObjToPhm);
673 xlat_mtx2 (temp, m_cx, m_cy);
674 mult_mtx2 (m_xformObjToPhm, temp, m_xformObjToPhm);
676 // to map world Phantom coodinates to normalized PElem coords
677 // translate by (-cx, -cy)
679 // scale by (1/u, 1/v)
681 xlat_mtx2 (m_xformPhmToObj, -m_cx, -m_cy);
682 rot_mtx2 (temp, -m_rot);
683 mult_mtx2 (m_xformPhmToObj, temp, m_xformPhmToObj);
684 scale_mtx2 (temp, 1 / m_u, 1 / m_v);
685 mult_mtx2 (m_xformPhmToObj, temp, m_xformPhmToObj);
690 * pelem_make_points INTERNAL routine to calculate point array for an pelem
693 * makepelempts (pelem)
694 * PELEM *pelem pelem whose points we are calculating
697 * Called by phm_add_pelem()
701 PhantomElement::makeVectorOutline ()
703 double radius, theta, start, stop;
709 case PELEM_RECTANGLE:
711 m_xOutline = new double [m_nPoints];
712 m_yOutline = new double [m_nPoints];
713 m_xOutline[0] =-m_u; m_yOutline[0] =-m_v;
714 m_xOutline[1] = m_u; m_yOutline[1] =-m_v;
715 m_xOutline[2] = m_u; m_yOutline[2] = m_v;
716 m_xOutline[3] =-m_u; m_yOutline[3] = m_v;
717 m_xOutline[4] =-m_u; m_yOutline[4] =-m_v;
721 m_xOutline = new double [m_nPoints];
722 m_yOutline = new double [m_nPoints];
723 m_xOutline[0] =-m_u; m_yOutline[0] = 0.0;
724 m_xOutline[1] = m_u; m_yOutline[1] = 0.0;
725 m_xOutline[2] = 0.0; m_yOutline[2] = m_v;
726 m_xOutline[3] =-m_u; m_yOutline[3] = 0.0;
729 cpts = numCirclePoints (TWOPI);
731 m_xOutline = new double [m_nPoints];
732 m_yOutline = new double [m_nPoints];
733 calcEllipsePoints (m_xOutline, m_yOutline, cpts, m_u, m_v);
736 radius = sqrt(m_u * m_u + m_v * m_v);
737 theta = atan(m_u / m_v); // angle with y-axis
738 start = 3.0 * HALFPI - theta;
739 stop = 3.0 * HALFPI + theta;
740 cpts = numCirclePoints (stop - start);
741 m_nPoints = 3 + cpts;
742 m_xOutline = new double [m_nPoints];
743 m_yOutline = new double [m_nPoints];
745 m_xOutline[0] = 0.0; m_yOutline[0] = m_v;
746 m_xOutline[1] =-m_u; m_yOutline[1] = 0.0;
747 calcArcPoints (&m_xOutline[2], &m_yOutline[2], cpts, 0.0, m_v, radius, start, stop);
748 m_xOutline[cpts + 2] = 0.0;
749 m_yOutline[cpts + 2] = m_v;
752 radius = sqrt(m_u * m_u + m_v * m_v);
753 theta = atan (m_u / m_v); // angle with y-axis
754 start = 3.0 * HALFPI - theta;
755 stop = 3.0 * HALFPI + theta;
757 cpts = numCirclePoints (stop - start);
758 m_nPoints = cpts + 1;
759 m_xOutline = new double [m_nPoints];
760 m_yOutline = new double [m_nPoints];
762 calcArcPoints (m_xOutline, m_yOutline, cpts, 0.0, m_v, radius, start, stop);
763 m_xOutline[cpts] = -m_u;
764 m_yOutline[cpts] = 0.0;
767 sys_error(ERR_WARNING, "illegal pelem type %d [makeVectorOutline]", m_type);
771 rotate2d (m_xOutline, m_yOutline, m_nPoints, m_rot);
772 xlat2d (m_xOutline, m_yOutline, m_nPoints, m_cx, m_cy);
774 minmax_array (m_xOutline, m_nPoints, m_xmin, m_xmax);
775 minmax_array (m_yOutline, m_nPoints, m_ymin, m_ymax);
777 // increase pelem extent by SCALE_PELEM_EXTENT to eliminate chance of
778 // missing actual pelem maximum due to polygonal sampling
780 xfact = (m_xmax - m_xmin) * SCALE_PELEM_EXTENT;
781 yfact = (m_ymax - m_ymin) * SCALE_PELEM_EXTENT;
791 * calc_arc Calculate outline of a arc of a circle
794 * calc_arc (x, y, xcent, ycent, pts, r, start, stop)
795 * double x[], y[]; Array of points
796 * int pts Number of points in array
797 * double xcent, ycent Center of cirlce
798 * double r Radius of circle
799 * double start, stop Beginning & ending angles
803 PhantomElement::calcArcPoints (double x[], double y[], const int pts, const double xcent, const double ycent, const double r, const double start, const double stop)
806 sys_error (ERR_WARNING, "negative or zero radius in calc_arc()");
808 double theta = (stop - start) / (pts - 1); // angle incr. between points
809 double c = cos(theta);
810 double s = sin(theta);
812 x[0] = r * cos (start) + xcent;
813 y[0] = r * sin (start) + ycent;
815 double xp = x[0] - xcent;
816 double yp = y[0] - ycent;
817 for (int i = 1; i < pts; i++) {
818 double xc = c * xp - s * yp;
819 double yc = s * xp + c * yp;
828 // PhantomElement::calcEllipsePoints Calculate outline of a ellipse
831 // calcEllipsePoints ()
836 PhantomElement::calcEllipsePoints (double x[], double y[], const int pts, const double u, const double v)
838 calcArcPoints (x, y, m_nPoints, 0.0, 0.0, 1.0, 0.0, TWOPI); // make a unit circle
839 scale2d (x, y, m_nPoints, m_u, m_v); // scale to ellipse
844 * circle_pts Calculate number of points to use for circle segment
847 * n = circle_pts (theta)
848 * int n Number of points to use for arc
849 * double theta Length of arc in radians
853 PhantomElement::numCirclePoints (double theta)
855 theta = clamp (theta, 0., TWOPI);
857 return static_cast<int> (POINTS_PER_CIRCLE * theta / TWOPI + 1.5);
862 PhantomElement::clipLineWorldCoords (double& x1, double& y1, double& x2, double &y2) const
864 /* check if ray is outside of pelem extents */
865 double cx1 = x1, cy1 = y1, cx2 = x2, cy2 = y2;
866 if (! clip_rect (cx1, cy1, cx2, cy2, m_rectLimits))
869 // convert phantom coordinates to pelem coordinates
870 xform_mtx2 (m_xformPhmToObj, x1, y1);
871 xform_mtx2 (m_xformPhmToObj, x2, y2);
873 if (! clipLineNormalizedCoords (x1, y1, x2, y2))
876 // convert standard pelem coordinates back to phantom coordinates
877 xform_mtx2 (m_xformObjToPhm, x1, y1);
878 xform_mtx2 (m_xformObjToPhm, x2, y2);
885 * pelem_clip_line Clip pelem against an arbitrary line
888 * pelem_clip_line (pelem, x1, y1, x2, y2)
889 * PhantomElement& pelem; Pelem to be clipped
890 * double *x1, *y1, *x2, *y2 Endpoints of line to be clipped
893 * true if line passes through pelem
894 * (x1, y1, x2, y2 hold coordinates of new line)
895 * false if line do not pass through pelem
896 * (x1, y1, x2, y2 are undefined)
900 PhantomElement::clipLineNormalizedCoords (double& x1, double& y1, double& x2, double& y2) const
905 case PELEM_RECTANGLE:
907 rect[0] = -1.0; rect[1] = -1.0;
908 rect[2] = 1.0; rect[3] = 1.0;
909 accept = clip_rect (x1, y1, x2, y2, rect);
912 accept = clip_circle (x1, y1, x2, y2, 0.0, 0.0, 1.0, 0.0, 0.0);
915 accept = clip_triangle (x1, y1, x2, y2, 1.0, 1.0, true);
918 accept = clip_segment (x1, y1, x2, y2, m_u, m_v);
921 accept = clip_sector (x1, y1, x2, y2, m_u, m_v);
924 sys_error (ERR_WARNING, "Illegal pelem type %d [pelem_clip_line]", m_type);
932 // METHOD IDENTIFICATION
933 // PhantomElement::isPointInside Check if point is inside pelem
936 // is_point_inside (pelem, x, y, coord_type)
937 // double x, y Point to see if lies in pelem
938 // int coord_type Coordinate type (PELEM_COORD or PHM_COORD)
941 // true if point lies within pelem
942 // false if point lies outside of pelem
945 PhantomElement::isPointInside (double x, double y, const CoordType coord_type) const
947 if (coord_type == PHM_COORD) {
948 xform_mtx2 (m_xformPhmToObj, x, y);
949 } else if (coord_type != PELEM_COORD) {
950 sys_error(ERR_WARNING, "Illegal coordinate type in pelem_is_point_inside");
955 case PELEM_RECTANGLE:
956 if (x > 1. || x < -1. || y > 1. || y < -1.)
962 if (y < 0. || y > 1. - x || y > 1. + x)
968 if (x > 1. || x < -1. || y > 1. || y < -1.)
970 if (x * x + y * y > 1.) // check if inside unit circle
976 // for clipping segments & sectors, must NOT scale by (1/u, 1/v)
977 // because this destroys information about size of arc component
980 if (x > 1. || x < -1. || y > 0.)
981 return (false); // clip against y > 0
982 x *= m_u; // put back u & v scale
984 if (x * x + (y-m_v) * (y-m_v) > m_u * m_u + m_v * m_v)
985 return (false); // clip against circle, r = sqrt(@)
990 if (x > 1. || x < -1. || y > 1.) // extent
992 if (y > 1. - x || y > 1. + x) // triangle
993 return (false); // clip against triangle
994 x *= m_u; // circle: put back u & v scale
996 if (x * x + (y-m_v) * (y-m_v) > m_u * m_u + m_v * m_v)
997 return (false); // clip against circle
1002 sys_error (ERR_WARNING, "Illegal pelem type in pelem_is_point_inside()");