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 1.23 2000/12/21 03:40:58 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);
234 * addPElem (type, cx, cy, u, v, rot, atten)
235 * char *type type of pelem (box, ellipse, etc)
236 * double cx, cy pelem center
237 * double u,v pelem size
238 * double rot rotation angle of pelem (in degrees)
239 * double atten x-ray attenuation cooefficient
243 Phantom::addPElem (const char *type, const double cx, const double cy, const double u, const double v, const double rot, const double atten)
245 PhantomElement *pelem = new PhantomElement (type, cx, cy, u, v, rot, atten);
247 m_listPElem.push_front (pelem);
249 // update phantom limits
250 if (m_xmin > pelem->xmin()) m_xmin = pelem->xmin();
251 if (m_xmax < pelem->xmax()) m_xmax = pelem->xmax();
252 if (m_ymin > pelem->ymin()) m_ymin = pelem->ymin();
253 if (m_ymax < pelem->ymax()) m_ymax = pelem->ymax();
255 if (m_diameter < pelem->diameter())
256 m_diameter = pelem->diameter();
258 // m_diameter = lineLength(m_xmin, m_ymin, m_xmax, m_ymax);
264 /*----------------------------------------------------------------------*/
265 /* Input-Output Routines */
266 /*----------------------------------------------------------------------*/
270 * print Print vertices of Phantom pelems
277 Phantom::print () const
279 printf("PRINTING Phantom\n\n");
280 printf("number of pelems in Phantom = %d\n", m_nPElem);
281 printf("limits: xmin=%8.2g ymin=%8.2g xmax=%8.2g ymax=%8.2g\n",
282 m_xmin, m_ymin, m_xmax, m_ymax);
284 for (PElemIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
286 printf("# pts=%3d atten = %7.4f rot = %7.2f (deg)\n",
287 (*i)->nOutlinePoints(), (*i)->atten(), convertRadiansToDegrees ((*i)->rot()));
289 printf("xmin=%7.3g ymin=%7.3g xmax=%7.3g ymax=%7.3g\n",
290 (*i)->xmin(), (*i)->ymin(), (*i)->xmax(), (*i)->ymax());
292 // for (int i = 0; i < m_nPoints; i++)
293 // printf("\t%8.3g %8.3g\n", i->xOutline()[i], i->yOutline()[i]);
299 * show Show vector outline of Phantom to user
307 Phantom::show () const
309 SGPDriver driverSGP ("Phantom Show");
314 std::cout << "Press return to continue";
319 Phantom::show (SGP& sgp) const
321 double wsize = m_xmax - m_xmin;
322 if ((m_ymax - m_ymin) > wsize)
323 wsize = m_ymax - m_ymin;
325 double halfWindow = wsize / 2;
327 double xcent = m_xmin + (m_xmax - m_xmin) / 2;
328 double ycent = m_ymin + (m_ymax - m_ymin) / 2;
330 sgp.setWindow (xcent - halfWindow, ycent - halfWindow, xcent + halfWindow, ycent + halfWindow);
338 * draw Draw vector outline of Phantom
346 Phantom::draw (SGP& sgp) const
348 for (PElemIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++)
349 sgp.polylineAbs ((*i)->xOutline(), (*i)->yOutline(), (*i)->nOutlinePoints());
355 * addStdSheppLogan Make head phantom of Shepp-Logan
358 * S. W. Rowland, "Computer Implementation of Image Reconstruction
359 * Formulas", in "Image Reconstruction from Projections: Implementation
360 * and Applications", edited by G. T. Herman, 1978.
364 Phantom::addStdSheppLogan ()
366 addPElem ("ellipse", 0.0000, 0.0000, 0.6900, 0.9200, 0.0, 1.00);
367 addPElem ("ellipse", 0.0000, -0.0184, 0.6624, 0.8740, 0.0, -0.98);
368 addPElem ("ellipse", 0.2200, 0.0000, 0.1100, 0.3100, -18.0, -0.02);
369 addPElem ("ellipse", -0.2200, 0.0000, 0.1600, 0.4100, 18.0, -0.02);
370 addPElem ("ellipse", 0.0000, 0.3500, 0.2100, 0.2500, 0.0, 0.01);
371 addPElem ("ellipse", 0.0000, 0.1000, 0.0460, 0.0460, 0.0, 0.01);
372 addPElem ("ellipse", 0.0000, -0.1000, 0.0460, 0.0460, 0.0, 0.01);
373 addPElem ("ellipse", -0.0800, -0.6050, 0.0460, 0.0230, 0.0, 0.01);
374 addPElem ("ellipse", 0.0000, -0.6050, 0.0230, 0.0230, 0.0, 0.01);
375 addPElem ("ellipse", 0.0600, -0.6050, 0.0230, 0.0230, 0.0, 0.01);
376 addPElem ("ellipse", 0.5538, -0.3858, 0.0330, 0.2060, -18.0, 0.03);
380 Phantom::addStdSheppLoganBordered ()
383 addPElem ("rectangle", 0.000, 0.0000, 0.8600, 1.150, 0.0, 0.00);
387 * addStdHerman Standard head phantom of G. T. Herman
390 * G. T. Herman, "Image Reconstructions from Projections: The Fundementals
391 * of Computed Tomography", 1979.
395 Phantom::addStdHerman ()
397 addPElem ("ellipse", 0.000, 1.50, 0.375, 0.3000, 90.00, -0.003);
398 addPElem ("ellipse", 0.675, -0.75, 0.225, 0.1500, 140.00, 0.010);
399 addPElem ("ellipse", 0.750, 1.50, 0.375, 0.2250, 50.00, 0.003);
400 addPElem ("segment", 1.375, -7.50, 1.100, 0.6250, 19.20, -0.204);
401 addPElem ("segment", 1.375, -7.50, 1.100, 4.3200, 19.21, 0.204);
402 addPElem ("segment", 0.000, -2.25, 1.125, 0.3750, 0.00, -0.003);
403 addPElem ("segment", 0.000, -2.25, 1.125, 3.0000, 0.00, 0.003);
404 addPElem ("segment", -1.000, 3.75, 1.000, 0.5000, 135.00, -0.003);
405 addPElem ("segment", -1.000, 3.75, 1.000, 3.0000, 135.00, 0.003);
406 addPElem ("segment", 1.000, 3.75, 1.000, 0.5000, 225.00, -0.003);
407 addPElem ("segment", 1.000, 3.75, 1.000, 3.0000, 225.00, 0.003);
408 addPElem ("triangle", 5.025, 3.75, 1.125, 0.5000, 110.75, 0.206);
409 addPElem ("triangle",-5.025, 3.75, 1.125, 0.9000,-110.75, 0.206);
410 addPElem ("ellipse", 0.000, 0.00, 8.625, 6.4687, 90.00, 0.416);
411 addPElem ("ellipse", 0.000, 0.00, 7.875, 5.7187, 90.00, -0.206);
415 Phantom::addStdHermanBordered ()
418 addPElem ("rectangle", 0.000, 0.00, 10.780, 8.110, 90.00, 0.000);
423 * convertToImagefile Make image array from Phantom
426 * pic_to_imagefile (pic, im, nsample)
427 * Phantom& pic Phantom definitions
428 * ImageFile *im Computed pixel array
429 * int nsample Number of samples along each axis for each pixel
430 * (total samples per pixel = nsample * nsample)
434 Phantom::convertToImagefile (ImageFile& im, const int in_nsample, const int trace) const
436 convertToImagefile (im, in_nsample, trace, 0, im.nx(), true);
440 Phantom::convertToImagefile (ImageFile& im, const int in_nsample, const int trace, const int colStart, const int colCount, bool bStoreAtColumnPos) const
444 if (nx < 2 || ny < 2)
447 int nsample = in_nsample;
451 double dx = m_xmax - m_xmin;
452 double dy = m_ymax - m_ymin;
453 double xcent = m_xmin + dx / 2;
454 double ycent = m_ymin + dy / 2;
455 double phmlen = (dx > dy ? dx : dy);
457 double phmradius = phmlen / 2;
459 double xmin = xcent - phmradius;
460 double xmax = xcent + phmradius;
461 double ymin = ycent - phmradius;
462 double ymax = ycent + phmradius;
464 // Each pixel holds the average of the intensity of the cell with (ix,iy) at the center of the pixel
465 // Set major increments so that the last cell v[nx-1][ny-1] will start at xmax - xinc, ymax - yinc).
466 // Set minor increments so that sample points are centered in cell
468 double xinc = (xmax - xmin) / nx;
469 double yinc = (ymax - ymin) / ny;
471 double kxinc = xinc / nsample; /* interval between samples */
472 double kyinc = yinc / nsample;
473 double kxofs = kxinc / 2; /* offset of 1st point */
474 double kyofs = kyinc / 2;
476 im.setAxisExtent (xmin, xmax, ymin, ymax);
477 im.setAxisIncrement (xinc, yinc);
479 ImageFileArray v = im.getArray();
481 for (int ix = 0; ix < colCount; ix++)
482 for (int iy = 0; iy < ny; iy++) {
484 if (bStoreAtColumnPos)
485 iColStore += colStart;
486 v[iColStore][iy] = 0;
489 double x_start = xmin + (colStart * xinc);
490 for (PElemConstIterator pelem = m_listPElem.begin(); pelem != m_listPElem.end(); pelem++) {
491 const PhantomElement& rPElem = **pelem;
494 for (ix = 0, x = x_start; ix < colCount; ix++, x += xinc) {
496 if (bStoreAtColumnPos)
497 iColStore += colStart;
498 for (iy = 0, y = ymin; iy < ny; iy++, y += yinc) {
499 for (kx = 0, xi = x + kxofs; kx < nsample; kx++, xi += kxinc) {
500 for (ky = 0, yi = y + kyofs; ky < nsample; ky++, yi += kyinc)
501 if (rPElem.isPointInside (xi, yi, PHM_COORD) == TRUE)
502 v[iColStore][iy] += rPElem.atten();
510 double factor = 1.0 / static_cast<double>(nsample * nsample);
513 for (int ix = 0; ix < colCount; ix++) {
514 int iColStore = ix;
\r
515 if (bStoreAtColumnPos)
\r
516 iColStore += colStart;
\r
517 for (int iy = 0; iy < ny; iy++)
518 v[iColStore][iy] *= factor;
\r
523 ////////////////////////////////////////////////////////////////////////////////////////////////////////
524 // CLASS IDENTIFICATION
530 ////////////////////////////////////////////////////////////////////////////////////////////////////////
533 PhantomElement::PhantomElement (const char *type, const double cx, const double cy, const double u, const double v, const double rot, const double atten)
534 : m_cx(cx), m_cy(cy), m_u(u), m_v(v), m_atten(atten), m_nPoints(0), m_xOutline(0), m_yOutline(0)
536 m_rot = convertDegreesToRadians (rot); // convert angle to radians
538 m_type = convertNameToType (type);
540 makeTransformMatrices (); // calc transform matrices between phantom and normalized phantomelement
541 makeVectorOutline (); // calculate vector outline of pelem
543 // Find maximum diameter of Object
545 for (int i = 0; i < m_nPoints; i++) {
546 double r2 = (m_xOutline[i] * m_xOutline[i]) + (m_yOutline[i] * m_yOutline[i]);
550 m_diameter = 2 * sqrt( r2Max );
552 m_rectLimits[0] = m_xmin; m_rectLimits[1] = m_ymin;
553 m_rectLimits[2] = m_xmax; m_rectLimits[3] = m_ymax;
557 PhantomElement::~PhantomElement ()
564 PhantomElement::convertNameToType (const char* const typeName)
566 PhmElemType type = PELEM_INVALID;
568 if (strcasecmp (typeName, "rectangle") == 0)
569 type = PELEM_RECTANGLE;
570 else if (strcasecmp (typeName, "triangle") == 0)
571 type = PELEM_TRIANGLE;
572 else if (strcasecmp (typeName, "ellipse") == 0)
573 type = PELEM_ELLIPSE;
574 else if (strcasecmp (typeName, "sector") == 0)
576 else if (strcasecmp (typeName, "segment") == 0)
577 type = PELEM_SEGMENT;
579 sys_error (ERR_WARNING, "Unknown PhantomElement type %s [PhantomElement::PhantomElement]", type);
585 PhantomElement::makeTransformMatrices ()
589 // To map normalized Pelem coords to world Phantom
592 // translate by (cx, cy)
594 scale_mtx2 (m_xformObjToPhm, m_u, m_v);
595 rot_mtx2 (temp, m_rot);
596 mult_mtx2 (m_xformObjToPhm, temp, m_xformObjToPhm);
597 xlat_mtx2 (temp, m_cx, m_cy);
598 mult_mtx2 (m_xformObjToPhm, temp, m_xformObjToPhm);
600 // to map world Phantom coodinates to normalized PElem coords
601 // translate by (-cx, -cy)
603 // scale by (1/u, 1/v)
605 xlat_mtx2 (m_xformPhmToObj, -m_cx, -m_cy);
606 rot_mtx2 (temp, -m_rot);
607 mult_mtx2 (m_xformPhmToObj, temp, m_xformPhmToObj);
608 scale_mtx2 (temp, 1 / m_u, 1 / m_v);
609 mult_mtx2 (m_xformPhmToObj, temp, m_xformPhmToObj);
614 * pelem_make_points INTERNAL routine to calculate point array for an pelem
617 * makepelempts (pelem)
618 * PELEM *pelem pelem whose points we are calculating
621 * Called by phm_add_pelem()
625 PhantomElement::makeVectorOutline ()
627 double radius, theta, start, stop;
633 case PELEM_RECTANGLE:
635 m_xOutline = new double [m_nPoints];
636 m_yOutline = new double [m_nPoints];
637 m_xOutline[0] =-m_u; m_yOutline[0] =-m_v;
638 m_xOutline[1] = m_u; m_yOutline[1] =-m_v;
639 m_xOutline[2] = m_u; m_yOutline[2] = m_v;
640 m_xOutline[3] =-m_u; m_yOutline[3] = m_v;
641 m_xOutline[4] =-m_u; m_yOutline[4] =-m_v;
645 m_xOutline = new double [m_nPoints];
646 m_yOutline = new double [m_nPoints];
647 m_xOutline[0] =-m_u; m_yOutline[0] = 0.0;
648 m_xOutline[1] = m_u; m_yOutline[1] = 0.0;
649 m_xOutline[2] = 0.0; m_yOutline[2] = m_v;
650 m_xOutline[3] =-m_u; m_yOutline[3] = 0.0;
653 cpts = numCirclePoints (TWOPI);
655 m_xOutline = new double [m_nPoints];
656 m_yOutline = new double [m_nPoints];
657 calcEllipsePoints (m_xOutline, m_yOutline, cpts, m_u, m_v);
660 radius = sqrt(m_u * m_u + m_v * m_v);
661 theta = atan(m_u / m_v); // angle with y-axis
662 start = 3.0 * HALFPI - theta;
663 stop = 3.0 * HALFPI + theta;
664 cpts = numCirclePoints (stop - start);
665 m_nPoints = 3 + cpts;
666 m_xOutline = new double [m_nPoints];
667 m_yOutline = new double [m_nPoints];
669 m_xOutline[0] = 0.0; m_yOutline[0] = m_v;
670 m_xOutline[1] =-m_u; m_yOutline[1] = 0.0;
671 calcArcPoints (&m_xOutline[2], &m_yOutline[2], cpts, 0.0, m_v, radius, start, stop);
672 m_xOutline[cpts + 2] = 0.0;
673 m_yOutline[cpts + 2] = m_v;
676 radius = sqrt(m_u * m_u + m_v * m_v);
677 theta = atan (m_u / m_v); // angle with y-axis
678 start = 3.0 * HALFPI - theta;
679 stop = 3.0 * HALFPI + theta;
681 cpts = numCirclePoints (stop - start);
682 m_nPoints = cpts + 1;
683 m_xOutline = new double [m_nPoints];
684 m_yOutline = new double [m_nPoints];
686 calcArcPoints (m_xOutline, m_yOutline, cpts, 0.0, m_v, radius, start, stop);
687 m_xOutline[cpts] = -m_u;
688 m_yOutline[cpts] = 0.0;
691 sys_error(ERR_WARNING, "illegal pelem type %d [makeVectorOutline]", m_type);
695 rotate2d (m_xOutline, m_yOutline, m_nPoints, m_rot);
696 xlat2d (m_xOutline, m_yOutline, m_nPoints, m_cx, m_cy);
698 minmax_array (m_xOutline, m_nPoints, m_xmin, m_xmax);
699 minmax_array (m_yOutline, m_nPoints, m_ymin, m_ymax);
701 // increase pelem extent by SCALE_PELEM_EXTENT to eliminate chance of
702 // missing actual pelem maximum due to polygonal sampling
704 xfact = (m_xmax - m_xmin) * SCALE_PELEM_EXTENT;
705 yfact = (m_ymax - m_ymin) * SCALE_PELEM_EXTENT;
715 * calc_arc Calculate outline of a arc of a circle
718 * calc_arc (x, y, xcent, ycent, pts, r, start, stop)
719 * double x[], y[]; Array of points
720 * int pts Number of points in array
721 * double xcent, ycent Center of cirlce
722 * double r Radius of circle
723 * double start, stop Beginning & ending angles
727 PhantomElement::calcArcPoints (double x[], double y[], const int pts, const double xcent, const double ycent, const double r, const double start, const double stop)
730 sys_error (ERR_WARNING, "negative or zero radius in calc_arc()");
732 double theta = (stop - start) / (pts - 1); // angle incr. between points
733 double c = cos(theta);
734 double s = sin(theta);
736 x[0] = r * cos (start) + xcent;
737 y[0] = r * sin (start) + ycent;
739 double xp = x[0] - xcent;
740 double yp = y[0] - ycent;
741 for (int i = 1; i < pts; i++) {
742 double xc = c * xp - s * yp;
743 double yc = s * xp + c * yp;
752 // PhantomElement::calcEllipsePoints Calculate outline of a ellipse
755 // calcEllipsePoints ()
760 PhantomElement::calcEllipsePoints (double x[], double y[], const int pts, const double u, const double v)
762 calcArcPoints (x, y, m_nPoints, 0.0, 0.0, 1.0, 0.0, TWOPI); // make a unit circle
763 scale2d (x, y, m_nPoints, m_u, m_v); // scale to ellipse
768 * circle_pts Calculate number of points to use for circle segment
771 * n = circle_pts (theta)
772 * int n Number of points to use for arc
773 * double theta Length of arc in radians
777 PhantomElement::numCirclePoints (double theta)
779 theta = clamp (theta, 0., TWOPI);
781 return static_cast<int> (POINTS_PER_CIRCLE * theta / TWOPI + 1.5);
786 PhantomElement::clipLineWorldCoords (double& x1, double& y1, double& x2, double &y2) const
788 /* check if ray is outside of pelem extents */
789 double cx1 = x1, cy1 = y1, cx2 = x2, cy2 = y2;
790 if (! clip_rect (cx1, cy1, cx2, cy2, m_rectLimits))
793 // convert phantom coordinates to pelem coordinates
794 xform_mtx2 (m_xformPhmToObj, x1, y1);
795 xform_mtx2 (m_xformPhmToObj, x2, y2);
797 if (! clipLineNormalizedCoords (x1, y1, x2, y2))
800 // convert standard pelem coordinates back to phantom coordinates
801 xform_mtx2 (m_xformObjToPhm, x1, y1);
802 xform_mtx2 (m_xformObjToPhm, x2, y2);
809 * pelem_clip_line Clip pelem against an arbitrary line
812 * pelem_clip_line (pelem, x1, y1, x2, y2)
813 * PhantomElement& pelem; Pelem to be clipped
814 * double *x1, *y1, *x2, *y2 Endpoints of line to be clipped
817 * true if line passes through pelem
818 * (x1, y1, x2, y2 hold coordinates of new line)
819 * false if line do not pass through pelem
820 * (x1, y1, x2, y2 are undefined)
824 PhantomElement::clipLineNormalizedCoords (double& x1, double& y1, double& x2, double& y2) const
829 case PELEM_RECTANGLE:
831 rect[0] = -1.0; rect[1] = -1.0;
832 rect[2] = 1.0; rect[3] = 1.0;
833 accept = clip_rect (x1, y1, x2, y2, rect);
836 accept = clip_circle (x1, y1, x2, y2, 0.0, 0.0, 1.0, 0.0, 0.0);
839 accept = clip_triangle (x1, y1, x2, y2, 1.0, 1.0, true);
842 accept = clip_segment (x1, y1, x2, y2, m_u, m_v);
845 accept = clip_sector (x1, y1, x2, y2, m_u, m_v);
848 sys_error (ERR_WARNING, "Illegal pelem type %d [pelem_clip_line]", m_type);
856 // METHOD IDENTIFICATION
857 // PhantomElement::isPointInside Check if point is inside pelem
860 // is_point_inside (pelem, x, y, coord_type)
861 // double x, y Point to see if lies in pelem
862 // int coord_type Coordinate type (PELEM_COORD or PHM_COORD)
865 // true if point lies within pelem
866 // false if point lies outside of pelem
869 PhantomElement::isPointInside (double x, double y, const CoordType coord_type) const
871 if (coord_type == PHM_COORD) {
872 xform_mtx2 (m_xformPhmToObj, x, y);
873 } else if (coord_type != PELEM_COORD) {
874 sys_error(ERR_WARNING, "Illegal coordinate type in pelem_is_point_inside");
879 case PELEM_RECTANGLE:
880 if (x > 1. || x < -1. || y > 1. || y < -1.)
886 if (y < 0. || y > 1. - x || y > 1. + x)
892 if (x > 1. || x < -1. || y > 1. || y < -1.)
894 if (x * x + y * y > 1.) // check if inside unit circle
900 // for clipping segments & sectors, must NOT scale by (1/u, 1/v)
901 // because this destroys information about size of arc component
904 if (x > 1. || x < -1. || y > 0.)
905 return (false); // clip against y > 0
906 x *= m_u; // put back u & v scale
908 if (x * x + (y-m_v) * (y-m_v) > m_u * m_u + m_v * m_v)
909 return (false); // clip against circle, r = sqrt(@)
914 if (x > 1. || x < -1. || y > 1.) // extent
916 if (y > 1. - x || y > 1. + x) // triangle
917 return (false); // clip against triangle
918 x *= m_u; // circle: put back u & v scale
920 if (x * x + (y-m_v) * (y-m_v) > m_u * m_u + m_v * m_v)
921 return (false); // clip against circle
926 sys_error (ERR_WARNING, "Illegal pelem type in pelem_is_point_inside()");