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 1.24 2001/01/02 05:33:37 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;
\r
31 const double PhantomElement::SCALE_PELEM_EXTENT=0.005; // increase pelem limits by 0.5%
\r
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)
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232 fstream file (fname, ios::out);
\r
235 printDefinitions (file);
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236 return ! file.fail();
\r
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++) {
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292 const PhantomElement& rPE = **i;
293 os << "PhantomElement: nPoints=" << rPE.nOutlinePoints();
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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";
304 Phantom::printDefinitions (std::ostream& os) const
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306 for (PElemConstIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
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307 const PhantomElement& rPE = **i;
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308 rPE.printDefinition (os);
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314 * show Show vector outline of Phantom to user
322 Phantom::show () const
324 SGPDriver driverSGP ("Phantom Show");
329 std::cout << "Press return to continue";
334 Phantom::show (SGP& sgp) const
336 double wsize = m_xmax - m_xmin;
337 if ((m_ymax - m_ymin) > wsize)
338 wsize = m_ymax - m_ymin;
340 double halfWindow = wsize / 2;
342 double xcent = m_xmin + (m_xmax - m_xmin) / 2;
343 double ycent = m_ymin + (m_ymax - m_ymin) / 2;
345 sgp.setWindow (xcent - halfWindow, ycent - halfWindow, xcent + halfWindow, ycent + halfWindow);
353 * draw Draw vector outline of Phantom
361 Phantom::draw (SGP& sgp) const
363 for (PElemIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++)
364 sgp.polylineAbs ((*i)->xOutline(), (*i)->yOutline(), (*i)->nOutlinePoints());
370 * addStdSheppLogan Make head phantom of Shepp-Logan
373 * S. W. Rowland, "Computer Implementation of Image Reconstruction
374 * Formulas", in "Image Reconstruction from Projections: Implementation
375 * and Applications", edited by G. T. Herman, 1978.
379 Phantom::addStdSheppLogan ()
381 addPElem ("ellipse", 0.0000, 0.0000, 0.6900, 0.9200, 0.0, 1.00);
382 addPElem ("ellipse", 0.0000, -0.0184, 0.6624, 0.8740, 0.0, -0.98);
383 addPElem ("ellipse", 0.2200, 0.0000, 0.1100, 0.3100, -18.0, -0.02);
384 addPElem ("ellipse", -0.2200, 0.0000, 0.1600, 0.4100, 18.0, -0.02);
385 addPElem ("ellipse", 0.0000, 0.3500, 0.2100, 0.2500, 0.0, 0.01);
386 addPElem ("ellipse", 0.0000, 0.1000, 0.0460, 0.0460, 0.0, 0.01);
387 addPElem ("ellipse", 0.0000, -0.1000, 0.0460, 0.0460, 0.0, 0.01);
388 addPElem ("ellipse", -0.0800, -0.6050, 0.0460, 0.0230, 0.0, 0.01);
389 addPElem ("ellipse", 0.0000, -0.6050, 0.0230, 0.0230, 0.0, 0.01);
390 addPElem ("ellipse", 0.0600, -0.6050, 0.0230, 0.0230, 0.0, 0.01);
391 addPElem ("ellipse", 0.5538, -0.3858, 0.0330, 0.2060, -18.0, 0.03);
395 Phantom::addStdSheppLoganBordered ()
398 addPElem ("rectangle", 0.000, 0.0000, 0.8600, 1.150, 0.0, 0.00);
402 * addStdHerman Standard head phantom of G. T. Herman
405 * G. T. Herman, "Image Reconstructions from Projections: The Fundementals
406 * of Computed Tomography", 1979.
410 Phantom::addStdHerman ()
412 addPElem ("ellipse", 0.000, 1.50, 0.375, 0.3000, 90.00, -0.003);
413 addPElem ("ellipse", 0.675, -0.75, 0.225, 0.1500, 140.00, 0.010);
414 addPElem ("ellipse", 0.750, 1.50, 0.375, 0.2250, 50.00, 0.003);
415 addPElem ("segment", 1.375, -7.50, 1.100, 0.6250, 19.20, -0.204);
416 addPElem ("segment", 1.375, -7.50, 1.100, 4.3200, 19.21, 0.204);
417 addPElem ("segment", 0.000, -2.25, 1.125, 0.3750, 0.00, -0.003);
418 addPElem ("segment", 0.000, -2.25, 1.125, 3.0000, 0.00, 0.003);
419 addPElem ("segment", -1.000, 3.75, 1.000, 0.5000, 135.00, -0.003);
420 addPElem ("segment", -1.000, 3.75, 1.000, 3.0000, 135.00, 0.003);
421 addPElem ("segment", 1.000, 3.75, 1.000, 0.5000, 225.00, -0.003);
422 addPElem ("segment", 1.000, 3.75, 1.000, 3.0000, 225.00, 0.003);
423 addPElem ("triangle", 5.025, 3.75, 1.125, 0.5000, 110.75, 0.206);
424 addPElem ("triangle",-5.025, 3.75, 1.125, 0.9000,-110.75, 0.206);
425 addPElem ("ellipse", 0.000, 0.00, 8.625, 6.4687, 90.00, 0.416);
426 addPElem ("ellipse", 0.000, 0.00, 7.875, 5.7187, 90.00, -0.206);
430 Phantom::addStdHermanBordered ()
433 addPElem ("rectangle", 0.000, 0.00, 10.780, 8.110, 90.00, 0.000);
438 * convertToImagefile Make image array from Phantom
441 * pic_to_imagefile (pic, im, nsample)
442 * Phantom& pic Phantom definitions
443 * ImageFile *im Computed pixel array
444 * int nsample Number of samples along each axis for each pixel
445 * (total samples per pixel = nsample * nsample)
449 Phantom::convertToImagefile (ImageFile& im, const int in_nsample, const int trace) const
451 convertToImagefile (im, in_nsample, trace, 0, im.nx(), true);
455 Phantom::convertToImagefile (ImageFile& im, const int in_nsample, const int trace, const int colStart, const int colCount, bool bStoreAtColumnPos) const
459 if (nx < 2 || ny < 2)
462 int nsample = in_nsample;
466 double dx = m_xmax - m_xmin;
467 double dy = m_ymax - m_ymin;
468 double xcent = m_xmin + dx / 2;
469 double ycent = m_ymin + dy / 2;
470 double phmlen = (dx > dy ? dx : dy);
472 double phmradius = phmlen / 2;
474 double xmin = xcent - phmradius;
475 double xmax = xcent + phmradius;
476 double ymin = ycent - phmradius;
477 double ymax = ycent + phmradius;
479 // Each pixel holds the average of the intensity of the cell with (ix,iy) at the center of the pixel
480 // Set major increments so that the last cell v[nx-1][ny-1] will start at xmax - xinc, ymax - yinc).
481 // Set minor increments so that sample points are centered in cell
483 double xinc = (xmax - xmin) / nx;
484 double yinc = (ymax - ymin) / ny;
486 double kxinc = xinc / nsample; /* interval between samples */
487 double kyinc = yinc / nsample;
488 double kxofs = kxinc / 2; /* offset of 1st point */
489 double kyofs = kyinc / 2;
491 im.setAxisExtent (xmin, xmax, ymin, ymax);
492 im.setAxisIncrement (xinc, yinc);
494 ImageFileArray v = im.getArray();
496 for (int ix = 0; ix < colCount; ix++)
497 for (int iy = 0; iy < ny; iy++) {
499 if (bStoreAtColumnPos)
500 iColStore += colStart;
501 v[iColStore][iy] = 0;
504 double x_start = xmin + (colStart * xinc);
505 for (PElemConstIterator pelem = m_listPElem.begin(); pelem != m_listPElem.end(); pelem++) {
506 const PhantomElement& rPElem = **pelem;
509 for (ix = 0, x = x_start; ix < colCount; ix++, x += xinc) {
511 if (bStoreAtColumnPos)
512 iColStore += colStart;
513 for (iy = 0, y = ymin; iy < ny; iy++, y += yinc) {
514 for (kx = 0, xi = x + kxofs; kx < nsample; kx++, xi += kxinc) {
515 for (ky = 0, yi = y + kyofs; ky < nsample; ky++, yi += kyinc)
516 if (rPElem.isPointInside (xi, yi, PHM_COORD) == TRUE)
517 v[iColStore][iy] += rPElem.atten();
525 double factor = 1.0 / static_cast<double>(nsample * nsample);
528 for (int ix = 0; ix < colCount; ix++) {
529 int iColStore = ix;
\r
530 if (bStoreAtColumnPos)
\r
531 iColStore += colStart;
\r
532 for (int iy = 0; iy < ny; iy++)
533 v[iColStore][iy] *= factor;
\r
538 ////////////////////////////////////////////////////////////////////////////////////////////////////////
539 // CLASS IDENTIFICATION
545 ////////////////////////////////////////////////////////////////////////////////////////////////////////
548 PhantomElement::PhantomElement (const char *type, const double cx, const double cy, const double u, const double v, const double rot, const double atten)
549 : m_cx(cx), m_cy(cy), m_u(u), m_v(v), m_atten(atten), m_nPoints(0), m_xOutline(0), m_yOutline(0)
551 m_rot = convertDegreesToRadians (rot); // convert angle to radians
553 m_type = convertNameToType (type);
555 makeTransformMatrices (); // calc transform matrices between phantom and normalized phantomelement
556 makeVectorOutline (); // calculate vector outline of pelem
558 // Find maximum diameter of Object
560 for (int i = 0; i < m_nPoints; i++) {
561 double r2 = (m_xOutline[i] * m_xOutline[i]) + (m_yOutline[i] * m_yOutline[i]);
565 m_diameter = 2 * sqrt( r2Max );
567 m_rectLimits[0] = m_xmin; m_rectLimits[1] = m_ymin;
568 m_rectLimits[2] = m_xmax; m_rectLimits[3] = m_ymax;
573 PhantomElement::~PhantomElement ()
580 PhantomElement::printDefinition (std::ostream& os) const
\r
582 os << convertTypeToName (m_type) << " " << m_cx << " " << m_cy << " " << m_u << " "
\r
583 << m_v << " " << convertRadiansToDegrees (m_rot) << " " << m_atten << "\n";
\r
587 PhantomElement::convertNameToType (const char* const typeName)
589 PhmElemType type = PELEM_INVALID;
591 if (strcasecmp (typeName, "rectangle") == 0)
592 type = PELEM_RECTANGLE;
593 else if (strcasecmp (typeName, "triangle") == 0)
594 type = PELEM_TRIANGLE;
595 else if (strcasecmp (typeName, "ellipse") == 0)
596 type = PELEM_ELLIPSE;
597 else if (strcasecmp (typeName, "sector") == 0)
599 else if (strcasecmp (typeName, "segment") == 0)
600 type = PELEM_SEGMENT;
602 sys_error (ERR_WARNING, "Unknown PhantomElement type %s [PhantomElement::PhantomElement]", type);
608 PhantomElement::convertTypeToName (PhmElemType iType)
\r
610 static char* pszType = "Unknown";
\r
612 if (iType == PELEM_RECTANGLE)
\r
613 pszType = "rectangle";
\r
614 else if (iType == PELEM_TRIANGLE)
\r
615 pszType = "triangle";
\r
616 else if (iType == PELEM_ELLIPSE)
\r
617 pszType = "ellipse";
\r
618 else if (iType == PELEM_SECTOR)
\r
619 pszType = "sector";
\r
620 else if (iType == PELEM_SEGMENT)
\r
621 pszType = "segment";
\r
628 PhantomElement::makeTransformMatrices ()
632 // To map normalized Pelem coords to world Phantom
635 // translate by (cx, cy)
637 scale_mtx2 (m_xformObjToPhm, m_u, m_v);
638 rot_mtx2 (temp, m_rot);
639 mult_mtx2 (m_xformObjToPhm, temp, m_xformObjToPhm);
640 xlat_mtx2 (temp, m_cx, m_cy);
641 mult_mtx2 (m_xformObjToPhm, temp, m_xformObjToPhm);
643 // to map world Phantom coodinates to normalized PElem coords
644 // translate by (-cx, -cy)
646 // scale by (1/u, 1/v)
648 xlat_mtx2 (m_xformPhmToObj, -m_cx, -m_cy);
649 rot_mtx2 (temp, -m_rot);
650 mult_mtx2 (m_xformPhmToObj, temp, m_xformPhmToObj);
651 scale_mtx2 (temp, 1 / m_u, 1 / m_v);
652 mult_mtx2 (m_xformPhmToObj, temp, m_xformPhmToObj);
657 * pelem_make_points INTERNAL routine to calculate point array for an pelem
660 * makepelempts (pelem)
661 * PELEM *pelem pelem whose points we are calculating
664 * Called by phm_add_pelem()
668 PhantomElement::makeVectorOutline ()
670 double radius, theta, start, stop;
676 case PELEM_RECTANGLE:
678 m_xOutline = new double [m_nPoints];
679 m_yOutline = new double [m_nPoints];
680 m_xOutline[0] =-m_u; m_yOutline[0] =-m_v;
681 m_xOutline[1] = m_u; m_yOutline[1] =-m_v;
682 m_xOutline[2] = m_u; m_yOutline[2] = m_v;
683 m_xOutline[3] =-m_u; m_yOutline[3] = m_v;
684 m_xOutline[4] =-m_u; m_yOutline[4] =-m_v;
688 m_xOutline = new double [m_nPoints];
689 m_yOutline = new double [m_nPoints];
690 m_xOutline[0] =-m_u; m_yOutline[0] = 0.0;
691 m_xOutline[1] = m_u; m_yOutline[1] = 0.0;
692 m_xOutline[2] = 0.0; m_yOutline[2] = m_v;
693 m_xOutline[3] =-m_u; m_yOutline[3] = 0.0;
696 cpts = numCirclePoints (TWOPI);
698 m_xOutline = new double [m_nPoints];
699 m_yOutline = new double [m_nPoints];
700 calcEllipsePoints (m_xOutline, m_yOutline, cpts, m_u, m_v);
703 radius = sqrt(m_u * m_u + m_v * m_v);
704 theta = atan(m_u / m_v); // angle with y-axis
705 start = 3.0 * HALFPI - theta;
706 stop = 3.0 * HALFPI + theta;
707 cpts = numCirclePoints (stop - start);
708 m_nPoints = 3 + cpts;
709 m_xOutline = new double [m_nPoints];
710 m_yOutline = new double [m_nPoints];
712 m_xOutline[0] = 0.0; m_yOutline[0] = m_v;
713 m_xOutline[1] =-m_u; m_yOutline[1] = 0.0;
714 calcArcPoints (&m_xOutline[2], &m_yOutline[2], cpts, 0.0, m_v, radius, start, stop);
715 m_xOutline[cpts + 2] = 0.0;
716 m_yOutline[cpts + 2] = m_v;
719 radius = sqrt(m_u * m_u + m_v * m_v);
720 theta = atan (m_u / m_v); // angle with y-axis
721 start = 3.0 * HALFPI - theta;
722 stop = 3.0 * HALFPI + theta;
724 cpts = numCirclePoints (stop - start);
725 m_nPoints = cpts + 1;
726 m_xOutline = new double [m_nPoints];
727 m_yOutline = new double [m_nPoints];
729 calcArcPoints (m_xOutline, m_yOutline, cpts, 0.0, m_v, radius, start, stop);
730 m_xOutline[cpts] = -m_u;
731 m_yOutline[cpts] = 0.0;
734 sys_error(ERR_WARNING, "illegal pelem type %d [makeVectorOutline]", m_type);
738 rotate2d (m_xOutline, m_yOutline, m_nPoints, m_rot);
739 xlat2d (m_xOutline, m_yOutline, m_nPoints, m_cx, m_cy);
741 minmax_array (m_xOutline, m_nPoints, m_xmin, m_xmax);
742 minmax_array (m_yOutline, m_nPoints, m_ymin, m_ymax);
744 // increase pelem extent by SCALE_PELEM_EXTENT to eliminate chance of
745 // missing actual pelem maximum due to polygonal sampling
747 xfact = (m_xmax - m_xmin) * SCALE_PELEM_EXTENT;
748 yfact = (m_ymax - m_ymin) * SCALE_PELEM_EXTENT;
758 * calc_arc Calculate outline of a arc of a circle
761 * calc_arc (x, y, xcent, ycent, pts, r, start, stop)
762 * double x[], y[]; Array of points
763 * int pts Number of points in array
764 * double xcent, ycent Center of cirlce
765 * double r Radius of circle
766 * double start, stop Beginning & ending angles
770 PhantomElement::calcArcPoints (double x[], double y[], const int pts, const double xcent, const double ycent, const double r, const double start, const double stop)
773 sys_error (ERR_WARNING, "negative or zero radius in calc_arc()");
775 double theta = (stop - start) / (pts - 1); // angle incr. between points
776 double c = cos(theta);
777 double s = sin(theta);
779 x[0] = r * cos (start) + xcent;
780 y[0] = r * sin (start) + ycent;
782 double xp = x[0] - xcent;
783 double yp = y[0] - ycent;
784 for (int i = 1; i < pts; i++) {
785 double xc = c * xp - s * yp;
786 double yc = s * xp + c * yp;
795 // PhantomElement::calcEllipsePoints Calculate outline of a ellipse
798 // calcEllipsePoints ()
803 PhantomElement::calcEllipsePoints (double x[], double y[], const int pts, const double u, const double v)
805 calcArcPoints (x, y, m_nPoints, 0.0, 0.0, 1.0, 0.0, TWOPI); // make a unit circle
806 scale2d (x, y, m_nPoints, m_u, m_v); // scale to ellipse
811 * circle_pts Calculate number of points to use for circle segment
814 * n = circle_pts (theta)
815 * int n Number of points to use for arc
816 * double theta Length of arc in radians
820 PhantomElement::numCirclePoints (double theta)
822 theta = clamp (theta, 0., TWOPI);
824 return static_cast<int> (POINTS_PER_CIRCLE * theta / TWOPI + 1.5);
829 PhantomElement::clipLineWorldCoords (double& x1, double& y1, double& x2, double &y2) const
831 /* check if ray is outside of pelem extents */
832 double cx1 = x1, cy1 = y1, cx2 = x2, cy2 = y2;
833 if (! clip_rect (cx1, cy1, cx2, cy2, m_rectLimits))
836 // convert phantom coordinates to pelem coordinates
837 xform_mtx2 (m_xformPhmToObj, x1, y1);
838 xform_mtx2 (m_xformPhmToObj, x2, y2);
840 if (! clipLineNormalizedCoords (x1, y1, x2, y2))
843 // convert standard pelem coordinates back to phantom coordinates
844 xform_mtx2 (m_xformObjToPhm, x1, y1);
845 xform_mtx2 (m_xformObjToPhm, x2, y2);
852 * pelem_clip_line Clip pelem against an arbitrary line
855 * pelem_clip_line (pelem, x1, y1, x2, y2)
856 * PhantomElement& pelem; Pelem to be clipped
857 * double *x1, *y1, *x2, *y2 Endpoints of line to be clipped
860 * true if line passes through pelem
861 * (x1, y1, x2, y2 hold coordinates of new line)
862 * false if line do not pass through pelem
863 * (x1, y1, x2, y2 are undefined)
867 PhantomElement::clipLineNormalizedCoords (double& x1, double& y1, double& x2, double& y2) const
872 case PELEM_RECTANGLE:
874 rect[0] = -1.0; rect[1] = -1.0;
875 rect[2] = 1.0; rect[3] = 1.0;
876 accept = clip_rect (x1, y1, x2, y2, rect);
879 accept = clip_circle (x1, y1, x2, y2, 0.0, 0.0, 1.0, 0.0, 0.0);
882 accept = clip_triangle (x1, y1, x2, y2, 1.0, 1.0, true);
885 accept = clip_segment (x1, y1, x2, y2, m_u, m_v);
888 accept = clip_sector (x1, y1, x2, y2, m_u, m_v);
891 sys_error (ERR_WARNING, "Illegal pelem type %d [pelem_clip_line]", m_type);
899 // METHOD IDENTIFICATION
900 // PhantomElement::isPointInside Check if point is inside pelem
903 // is_point_inside (pelem, x, y, coord_type)
904 // double x, y Point to see if lies in pelem
905 // int coord_type Coordinate type (PELEM_COORD or PHM_COORD)
908 // true if point lies within pelem
909 // false if point lies outside of pelem
912 PhantomElement::isPointInside (double x, double y, const CoordType coord_type) const
914 if (coord_type == PHM_COORD) {
915 xform_mtx2 (m_xformPhmToObj, x, y);
916 } else if (coord_type != PELEM_COORD) {
917 sys_error(ERR_WARNING, "Illegal coordinate type in pelem_is_point_inside");
922 case PELEM_RECTANGLE:
923 if (x > 1. || x < -1. || y > 1. || y < -1.)
929 if (y < 0. || y > 1. - x || y > 1. + x)
935 if (x > 1. || x < -1. || y > 1. || y < -1.)
937 if (x * x + y * y > 1.) // check if inside unit circle
943 // for clipping segments & sectors, must NOT scale by (1/u, 1/v)
944 // because this destroys information about size of arc component
947 if (x > 1. || x < -1. || y > 0.)
948 return (false); // clip against y > 0
949 x *= m_u; // put back u & v scale
951 if (x * x + (y-m_v) * (y-m_v) > m_u * m_u + m_v * m_v)
952 return (false); // clip against circle, r = sqrt(@)
957 if (x > 1. || x < -1. || y > 1.) // extent
959 if (y > 1. - x || y > 1. + x) // triangle
960 return (false); // clip against triangle
961 x *= m_u; // circle: put back u & v scale
963 if (x * x + (y-m_v) * (y-m_v) > m_u * m_u + m_v * m_v)
964 return (false); // clip against circle
969 sys_error (ERR_WARNING, "Illegal pelem type in pelem_is_point_inside()");