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 1.19 2000/11/09 00:12:25 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 ******************************************************************************/
31 const int Phantom::PHM_INVALID = -1;
32 const int Phantom::PHM_HERMAN = 0;
33 const int Phantom::PHM_B_HERMAN = 1;
34 const int Phantom::PHM_SHEPP_LOGAN = 2;
35 const int Phantom::PHM_B_SHEPP_LOGAN = 3;
36 const int Phantom::PHM_UNITPULSE = 4;
38 const char* Phantom::s_aszPhantomName[] =
47 const char* Phantom::s_aszPhantomTitle[] =
50 {"Herman Head (Bordered)"},
52 {"Shepp-Logan (Bordered)"},
56 const int Phantom::s_iPhantomCount = sizeof(s_aszPhantomName) / sizeof(const char*);
59 // CLASS IDENTIFICATION
69 Phantom::Phantom (const char* const phmName)
72 createFromPhantom (phmName);
84 m_composition = P_PELEMS;
91 for (PElemIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
98 Phantom::convertPhantomIDToName (int phmID)
100 static const char *name = "";
102 if (phmID >= 0 && phmID < s_iPhantomCount)
103 return (s_aszPhantomName[phmID]);
109 Phantom::convertPhantomIDToTitle (int phmID)
111 static const char *title = "";
113 if (phmID >= 0 && phmID < s_iPhantomCount)
114 return (s_aszPhantomName[phmID]);
120 Phantom::convertNameToPhantomID (const char* const phmName)
122 int id = PHM_INVALID;
124 for (int i = 0; i < s_iPhantomCount; i++)
125 if (strcasecmp (phmName, s_aszPhantomName[i]) == 0) {
135 Phantom::createFromPhantom (const char* const phmName)
137 int phmid = convertNameToPhantomID (phmName);
138 if (phmid == PHM_INVALID) {
140 m_failMessage = "Invalid phantom name ";
141 m_failMessage += phmName;
146 createFromPhantom (phmid);
151 Phantom::createFromPhantom (const int phmid)
159 addStdHermanBordered();
161 case PHM_SHEPP_LOGAN:
164 case PHM_B_SHEPP_LOGAN:
165 addStdSheppLoganBordered();
168 m_composition = P_UNIT_PULSE;
169 addPElem ("rectangle", 0., 0., 100., 100., 0., 0.); // outline
170 addPElem ("ellipse", 0., 0., 1., 1., 0., 1.); // pulse
174 m_failMessage = "Illegal phantom id ";
175 m_failMessage += phmid;
185 /* METHOD IDENTIFICATION
186 * createFromFile Add PhantomElements from file
189 * createFromFile (filename)
192 * true if pelem were added
193 * false if an pelem not added
197 Phantom::createFromFile (const char* const fname)
199 bool bGoodFile = true;
202 if ((fp = fopen (fname, "r")) == NULL)
208 double cx, cy, u, v, rot, dens;
211 int status = fscanf (fp, "%79s %lf %lf %lf %lf %lf %lf", pelemtype, &cx, &cy, &u, &v, &rot, &dens);
213 if (status == static_cast<int>(EOF))
215 else if (status != 7) {
216 sys_error (ERR_WARNING, "Insufficient fields reading phantom file %s [Phantom::createFromFile]", fname);
219 addPElem (pelemtype, cx, cy, u, v, rot, dens);
232 * addPElem (type, cx, cy, u, v, rot, atten)
233 * char *type type of pelem (box, ellipse, etc)
234 * double cx, cy pelem center
235 * double u,v pelem size
236 * double rot rotation angle of pelem (in degrees)
237 * double atten x-ray attenuation cooefficient
241 Phantom::addPElem (const char *type, const double cx, const double cy, const double u, const double v, const double rot, const double atten)
243 PhantomElement *pelem = new PhantomElement (type, cx, cy, u, v, rot, atten);
245 m_listPElem.push_front (pelem);
247 // update phantom limits
248 if (m_xmin > pelem->xmin()) m_xmin = pelem->xmin();
249 if (m_xmax < pelem->xmax()) m_xmax = pelem->xmax();
250 if (m_ymin > pelem->ymin()) m_ymin = pelem->ymin();
251 if (m_ymax < pelem->ymax()) m_ymax = pelem->ymax();
253 if (m_diameter < pelem->diameter())
254 m_diameter = pelem->diameter();
256 // m_diameter = lineLength(m_xmin, m_ymin, m_xmax, m_ymax);
262 /*----------------------------------------------------------------------*/
263 /* Input-Output Routines */
264 /*----------------------------------------------------------------------*/
268 * print Print vertices of Phantom pelems
275 Phantom::print () const
277 printf("PRINTING Phantom\n\n");
278 printf("number of pelems in Phantom = %d\n", m_nPElem);
279 printf("limits: xmin=%8.2g ymin=%8.2g xmax=%8.2g ymax=%8.2g\n",
280 m_xmin, m_ymin, m_xmax, m_ymax);
282 for (PElemIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++) {
284 printf("# pts=%3d atten = %7.4f rot = %7.2f (deg)\n",
285 (*i)->nOutlinePoints(), (*i)->atten(), convertRadiansToDegrees ((*i)->rot()));
287 printf("xmin=%7.3g ymin=%7.3g xmax=%7.3g ymax=%7.3g\n",
288 (*i)->xmin(), (*i)->ymin(), (*i)->xmax(), (*i)->ymax());
290 // for (int i = 0; i < m_nPoints; i++)
291 // printf("\t%8.3g %8.3g\n", i->xOutline()[i], i->yOutline()[i]);
297 * show Show vector outline of Phantom to user
305 Phantom::show () const
307 SGPDriver driverSGP ("Phantom Show");
312 cout << "Press return to continue";
317 Phantom::show (SGP& sgp) const
319 double wsize = m_xmax - m_xmin;
320 if ((m_ymax - m_ymin) > wsize)
321 wsize = m_ymax - m_ymin;
323 double halfWindow = wsize / 2;
325 double xcent = m_xmin + (m_xmax - m_xmin) / 2;
326 double ycent = m_ymin + (m_ymax - m_ymin) / 2;
328 sgp.setWindow (xcent - halfWindow, ycent - halfWindow, xcent + halfWindow, ycent + halfWindow);
336 * draw Draw vector outline of Phantom
344 Phantom::draw (SGP& sgp) const
346 for (PElemIterator i = m_listPElem.begin(); i != m_listPElem.end(); i++)
347 sgp.polylineAbs ((*i)->xOutline(), (*i)->yOutline(), (*i)->nOutlinePoints());
353 * addStdSheppLogan Make head phantom of Shepp-Logan
356 * S. W. Rowland, "Computer Implementation of Image Reconstruction
357 * Formulas", in "Image Reconstruction from Projections: Implementation
358 * and Applications", edited by G. T. Herman, 1978.
362 Phantom::addStdSheppLogan ()
364 addPElem ("ellipse", 0.0000, 0.0000, 0.6900, 0.9200, 0.0, 1.00);
365 addPElem ("ellipse", 0.0000, -0.0184, 0.6624, 0.8740, 0.0, -0.98);
366 addPElem ("ellipse", 0.2200, 0.0000, 0.1100, 0.3100, -18.0, -0.02);
367 addPElem ("ellipse", -0.2200, 0.0000, 0.1600, 0.4100, 18.0, -0.02);
368 addPElem ("ellipse", 0.0000, 0.3500, 0.2100, 0.2500, 0.0, 0.01);
369 addPElem ("ellipse", 0.0000, 0.1000, 0.0460, 0.0460, 0.0, 0.01);
370 addPElem ("ellipse", 0.0000, -0.1000, 0.0460, 0.0460, 0.0, 0.01);
371 addPElem ("ellipse", -0.0800, -0.6050, 0.0460, 0.0230, 0.0, 0.01);
372 addPElem ("ellipse", 0.0000, -0.6050, 0.0230, 0.0230, 0.0, 0.01);
373 addPElem ("ellipse", 0.0600, -0.6050, 0.0230, 0.0230, 0.0, 0.01);
374 addPElem ("ellipse", 0.5538, -0.3858, 0.0330, 0.2060, -18.0, 0.03);
378 Phantom::addStdSheppLoganBordered ()
381 addPElem ("rectangle", 0.000, 0.0000, 0.8600, 1.150, 0.0, 0.00);
385 * addStdHerman Standard head phantom of G. T. Herman
388 * G. T. Herman, "Image Reconstructions from Projections: The Fundementals
389 * of Computed Tomography", 1979.
393 Phantom::addStdHerman ()
395 addPElem ("ellipse", 0.000, 1.50, 0.375, 0.3000, 90.00, -0.003);
396 addPElem ("ellipse", 0.675, -0.75, 0.225, 0.1500, 140.00, 0.010);
397 addPElem ("ellipse", 0.750, 1.50, 0.375, 0.2250, 50.00, 0.003);
398 addPElem ("segment", 1.375, -7.50, 1.100, 0.6250, 19.20, -0.204);
399 addPElem ("segment", 1.375, -7.50, 1.100, 4.3200, 19.21, 0.204);
400 addPElem ("segment", 0.000, -2.25, 1.125, 0.3750, 0.00, -0.003);
401 addPElem ("segment", 0.000, -2.25, 1.125, 3.0000, 0.00, 0.003);
402 addPElem ("segment", -1.000, 3.75, 1.000, 0.5000, 135.00, -0.003);
403 addPElem ("segment", -1.000, 3.75, 1.000, 3.0000, 135.00, 0.003);
404 addPElem ("segment", 1.000, 3.75, 1.000, 0.5000, 225.00, -0.003);
405 addPElem ("segment", 1.000, 3.75, 1.000, 3.0000, 225.00, 0.003);
406 addPElem ("triangle", 5.025, 3.75, 1.125, 0.5000, 110.75, 0.206);
407 addPElem ("triangle",-5.025, 3.75, 1.125, 0.9000,-110.75, 0.206);
408 addPElem ("ellipse", 0.000, 0.00, 8.625, 6.4687, 90.00, 0.416);
409 addPElem ("ellipse", 0.000, 0.00, 7.875, 5.7187, 90.00, -0.206);
413 Phantom::addStdHermanBordered ()
416 addPElem ("rectangle", 0.000, 0.00, 10.780, 8.110, 90.00, 0.000);
421 * convertToImagefile Make image array from Phantom
424 * pic_to_imagefile (pic, im, nsample)
425 * Phantom& pic Phantom definitions
426 * ImageFile *im Computed pixel array
427 * int nsample Number of samples along each axis for each pixel
428 * (total samples per pixel = nsample * nsample)
432 Phantom::convertToImagefile (ImageFile& im, const int in_nsample, const int trace) const
434 convertToImagefile (im, in_nsample, trace, 0, im.nx(), true);
438 Phantom::convertToImagefile (ImageFile& im, const int in_nsample, const int trace, const int colStart, const int colCount, bool bStoreAtColumnPos) const
442 if (nx < 2 || ny < 2)
445 int nsample = in_nsample;
449 double dx = m_xmax - m_xmin;
450 double dy = m_ymax - m_ymin;
451 double xcent = m_xmin + dx / 2;
452 double ycent = m_ymin + dy / 2;
453 double phmlen = (dx > dy ? dx : dy);
455 double phmradius = phmlen / 2;
457 double xmin = xcent - phmradius;
458 double xmax = xcent + phmradius;
459 double ymin = ycent - phmradius;
460 double ymax = ycent + phmradius;
462 // Each pixel holds the average of the intensity of the cell with (ix,iy) at the center of the pixel
463 // Set major increments so that the last cell v[nx-1][ny-1] will start at xmax - xinc, ymax - yinc).
464 // Set minor increments so that sample points are centered in cell
466 double xinc = (xmax - xmin) / nx;
467 double yinc = (ymax - ymin) / ny;
469 double kxinc = xinc / nsample; /* interval between samples */
470 double kyinc = yinc / nsample;
471 double kxofs = kxinc / 2; /* offset of 1st point */
472 double kyofs = kyinc / 2;
474 im.setAxisExtent (xmin, xmax, ymin, ymax);
475 im.setAxisIncrement (xinc, yinc);
477 ImageFileArray v = im.getArray();
479 for (int ix = 0; ix < colCount; ix++)
480 for (int iy = 0; iy < ny; iy++) {
482 if (bStoreAtColumnPos)
483 iColStore += colStart;
484 v[iColStore][iy] = 0;
487 double x_start = xmin + (colStart * xinc);
488 for (PElemConstIterator pelem = m_listPElem.begin(); pelem != m_listPElem.end(); pelem++) {
489 const PhantomElement& rPElem = **pelem;
492 for (ix = 0, x = x_start; ix < colCount; ix++, x += xinc) {
494 if (bStoreAtColumnPos)
495 iColStore += colStart;
496 for (iy = 0, y = ymin; iy < ny; iy++, y += yinc) {
497 for (kx = 0, xi = x + kxofs; kx < nsample; kx++, xi += kxinc) {
498 for (ky = 0, yi = y + kyofs; ky < nsample; ky++, yi += kyinc)
499 if (rPElem.isPointInside (xi, yi, PHM_COORD) == TRUE)
500 v[iColStore][iy] += rPElem.atten();
508 double factor = 1.0 / (nsample * nsample);
510 for (int ix = 0; ix < colCount; ix++)
511 for (int iy = 0; iy < ny; iy++)
516 ////////////////////////////////////////////////////////////////////////////////////////////////////////
517 // CLASS IDENTIFICATION
523 ////////////////////////////////////////////////////////////////////////////////////////////////////////
526 PhantomElement::PhantomElement (const char *type, const double cx, const double cy, const double u, const double v, const double rot, const double atten)
527 : m_cx(cx), m_cy(cy), m_u(u), m_v(v), m_atten(atten), m_nPoints(0), m_xOutline(0), m_yOutline(0)
529 m_rot = convertDegreesToRadians (rot); // convert angle to radians
531 m_type = convertNameToType (type);
533 makeTransformMatrices (); // calc transform matrices between phantom and normalized phantomelement
534 makeVectorOutline (); // calculate vector outline of pelem
536 // Find maximum diameter of Object
538 for (int i = 0; i < m_nPoints; i++) {
539 double r2 = (m_xOutline[i] * m_xOutline[i]) + (m_yOutline[i] * m_yOutline[i]);
543 m_diameter = 2 * sqrt( r2Max );
545 m_rectLimits[0] = m_xmin; m_rectLimits[1] = m_ymin;
546 m_rectLimits[2] = m_xmax; m_rectLimits[3] = m_ymax;
550 PhantomElement::~PhantomElement ()
557 PhantomElement::convertNameToType (const char* const typeName)
559 PhmElemType type = PELEM_INVALID;
561 if (strcasecmp (typeName, "rectangle") == 0)
562 type = PELEM_RECTANGLE;
563 else if (strcasecmp (typeName, "triangle") == 0)
564 type = PELEM_TRIANGLE;
565 else if (strcasecmp (typeName, "ellipse") == 0)
566 type = PELEM_ELLIPSE;
567 else if (strcasecmp (typeName, "sector") == 0)
569 else if (strcasecmp (typeName, "segment") == 0)
570 type = PELEM_SEGMENT;
572 sys_error (ERR_WARNING, "Unknown PhantomElement type %s [PhantomElement::PhantomElement]", type);
578 PhantomElement::makeTransformMatrices ()
582 // To map normalized Pelem coords to world Phantom
585 // translate by (cx, cy)
587 scale_mtx2 (m_xformObjToPhm, m_u, m_v);
588 rot_mtx2 (temp, m_rot);
589 mult_mtx2 (m_xformObjToPhm, temp, m_xformObjToPhm);
590 xlat_mtx2 (temp, m_cx, m_cy);
591 mult_mtx2 (m_xformObjToPhm, temp, m_xformObjToPhm);
593 // to map world Phantom coodinates to normalized PElem coords
594 // translate by (-cx, -cy)
596 // scale by (1/u, 1/v)
598 xlat_mtx2 (m_xformPhmToObj, -m_cx, -m_cy);
599 rot_mtx2 (temp, -m_rot);
600 mult_mtx2 (m_xformPhmToObj, temp, m_xformPhmToObj);
601 scale_mtx2 (temp, 1 / m_u, 1 / m_v);
602 mult_mtx2 (m_xformPhmToObj, temp, m_xformPhmToObj);
607 * pelem_make_points INTERNAL routine to calculate point array for an pelem
610 * makepelempts (pelem)
611 * PELEM *pelem pelem whose points we are calculating
614 * Called by phm_add_pelem()
618 PhantomElement::makeVectorOutline ()
620 double radius, theta, start, stop;
626 case PELEM_RECTANGLE:
628 m_xOutline = new double [m_nPoints];
629 m_yOutline = new double [m_nPoints];
630 m_xOutline[0] =-m_u; m_yOutline[0] =-m_v;
631 m_xOutline[1] = m_u; m_yOutline[1] =-m_v;
632 m_xOutline[2] = m_u; m_yOutline[2] = m_v;
633 m_xOutline[3] =-m_u; m_yOutline[3] = m_v;
634 m_xOutline[4] =-m_u; m_yOutline[4] =-m_v;
638 m_xOutline = new double [m_nPoints];
639 m_yOutline = new double [m_nPoints];
640 m_xOutline[0] =-m_u; m_yOutline[0] = 0.0;
641 m_xOutline[1] = m_u; m_yOutline[1] = 0.0;
642 m_xOutline[2] = 0.0; m_yOutline[2] = m_v;
643 m_xOutline[3] =-m_u; m_yOutline[3] = 0.0;
646 cpts = numCirclePoints (TWOPI);
648 m_xOutline = new double [m_nPoints];
649 m_yOutline = new double [m_nPoints];
650 calcEllipsePoints (m_xOutline, m_yOutline, cpts, m_u, m_v);
653 radius = sqrt(m_u * m_u + m_v * m_v);
654 theta = atan(m_u / m_v); // angle with y-axis
655 start = 3.0 * HALFPI - theta;
656 stop = 3.0 * HALFPI + theta;
657 cpts = numCirclePoints (stop - start);
658 m_nPoints = 3 + cpts;
659 m_xOutline = new double [m_nPoints];
660 m_yOutline = new double [m_nPoints];
662 m_xOutline[0] = 0.0; m_yOutline[0] = m_v;
663 m_xOutline[1] =-m_u; m_yOutline[1] = 0.0;
664 calcArcPoints (&m_xOutline[2], &m_yOutline[2], cpts, 0.0, m_v, radius, start, stop);
665 m_xOutline[cpts + 2] = 0.0;
666 m_yOutline[cpts + 2] = m_v;
669 radius = sqrt(m_u * m_u + m_v * m_v);
670 theta = atan (m_u / m_v); // angle with y-axis
671 start = 3.0 * HALFPI - theta;
672 stop = 3.0 * HALFPI + theta;
674 cpts = numCirclePoints (stop - start);
675 m_nPoints = cpts + 1;
676 m_xOutline = new double [m_nPoints];
677 m_yOutline = new double [m_nPoints];
679 calcArcPoints (m_xOutline, m_yOutline, cpts, 0.0, m_v, radius, start, stop);
680 m_xOutline[cpts] = -m_u;
681 m_yOutline[cpts] = 0.0;
684 sys_error(ERR_WARNING, "illegal pelem type %d [makeVectorOutline]", m_type);
688 rotate2d (m_xOutline, m_yOutline, m_nPoints, m_rot);
689 xlat2d (m_xOutline, m_yOutline, m_nPoints, m_cx, m_cy);
691 minmax_array (m_xOutline, m_nPoints, m_xmin, m_xmax);
692 minmax_array (m_yOutline, m_nPoints, m_ymin, m_ymax);
694 // increase pelem extent by SCALE_PELEM_EXTENT to eliminate chance of
695 // missing actual pelem maximum due to polygonal sampling
697 xfact = (m_xmax - m_xmin) * SCALE_PELEM_EXTENT;
698 yfact = (m_ymax - m_ymin) * SCALE_PELEM_EXTENT;
708 * calc_arc Calculate outline of a arc of a circle
711 * calc_arc (x, y, xcent, ycent, pts, r, start, stop)
712 * double x[], y[]; Array of points
713 * int pts Number of points in array
714 * double xcent, ycent Center of cirlce
715 * double r Radius of circle
716 * double start, stop Beginning & ending angles
720 PhantomElement::calcArcPoints (double x[], double y[], const int pts, const double xcent, const double ycent, const double r, const double start, const double stop)
723 sys_error (ERR_WARNING, "negative or zero radius in calc_arc()");
725 double theta = (stop - start) / (pts - 1); // angle incr. between points
726 double c = cos(theta);
727 double s = sin(theta);
729 x[0] = r * cos (start) + xcent;
730 y[0] = r * sin (start) + ycent;
732 double xp = x[0] - xcent;
733 double yp = y[0] - ycent;
734 for (int i = 1; i < pts; i++) {
735 double xc = c * xp - s * yp;
736 double yc = s * xp + c * yp;
745 // PhantomElement::calcEllipsePoints Calculate outline of a ellipse
748 // calcEllipsePoints ()
753 PhantomElement::calcEllipsePoints (double x[], double y[], const int pts, const double u, const double v)
755 calcArcPoints (x, y, m_nPoints, 0.0, 0.0, 1.0, 0.0, TWOPI); // make a unit circle
756 scale2d (x, y, m_nPoints, m_u, m_v); // scale to ellipse
761 * circle_pts Calculate number of points to use for circle segment
764 * n = circle_pts (theta)
765 * int n Number of points to use for arc
766 * double theta Length of arc in radians
770 PhantomElement::numCirclePoints (double theta)
772 theta = clamp (theta, 0., TWOPI);
774 return static_cast<int> (POINTS_PER_CIRCLE * theta / TWOPI + 1.5);
779 PhantomElement::clipLineWorldCoords (double& x1, double& y1, double& x2, double &y2) const
781 /* check if ray is outside of pelem extents */
782 double cx1 = x1, cy1 = y1, cx2 = x2, cy2 = y2;
783 if (! clip_rect (cx1, cy1, cx2, cy2, m_rectLimits))
786 // convert phantom coordinates to pelem coordinates
787 xform_mtx2 (m_xformPhmToObj, x1, y1);
788 xform_mtx2 (m_xformPhmToObj, x2, y2);
790 if (! clipLineNormalizedCoords (x1, y1, x2, y2))
793 // convert standard pelem coordinates back to phantom coordinates
794 xform_mtx2 (m_xformObjToPhm, x1, y1);
795 xform_mtx2 (m_xformObjToPhm, x2, y2);
802 * pelem_clip_line Clip pelem against an arbitrary line
805 * pelem_clip_line (pelem, x1, y1, x2, y2)
806 * PhantomElement& pelem; Pelem to be clipped
807 * double *x1, *y1, *x2, *y2 Endpoints of line to be clipped
810 * true if line passes through pelem
811 * (x1, y1, x2, y2 hold coordinates of new line)
812 * false if line do not pass through pelem
813 * (x1, y1, x2, y2 are undefined)
817 PhantomElement::clipLineNormalizedCoords (double& x1, double& y1, double& x2, double& y2) const
822 case PELEM_RECTANGLE:
824 rect[0] = -1.0; rect[1] = -1.0;
825 rect[2] = 1.0; rect[3] = 1.0;
826 accept = clip_rect (x1, y1, x2, y2, rect);
829 accept = clip_circle (x1, y1, x2, y2, 0.0, 0.0, 1.0, 0.0, 0.0);
832 accept = clip_triangle (x1, y1, x2, y2, 1.0, 1.0, true);
835 accept = clip_segment (x1, y1, x2, y2, m_u, m_v);
838 accept = clip_sector (x1, y1, x2, y2, m_u, m_v);
841 sys_error (ERR_WARNING, "Illegal pelem type %d [pelem_clip_line]", m_type);
849 // METHOD IDENTIFICATION
850 // PhantomElement::isPointInside Check if point is inside pelem
853 // is_point_inside (pelem, x, y, coord_type)
854 // double x, y Point to see if lies in pelem
855 // int coord_type Coordinate type (PELEM_COORD or PHM_COORD)
858 // true if point lies within pelem
859 // false if point lies outside of pelem
862 PhantomElement::isPointInside (double x, double y, const CoordType coord_type) const
864 if (coord_type == PHM_COORD) {
865 xform_mtx2 (m_xformPhmToObj, x, y);
866 } else if (coord_type != PELEM_COORD) {
867 sys_error(ERR_WARNING, "Illegal coordinate type in pelem_is_point_inside");
872 case PELEM_RECTANGLE:
873 if (x > 1. || x < -1. || y > 1. || y < -1.)
879 if (y < 0. || y > 1. - x || y > 1. + x)
885 if (x > 1. || x < -1. || y > 1. || y < -1.)
887 if (x * x + y * y > 1.) // check if inside unit circle
893 // for clipping segments & sectors, must NOT scale by (1/u, 1/v)
894 // because this destroys information about size of arc component
897 if (x > 1. || x < -1. || y > 0.)
898 return (false); // clip against y > 0
899 x *= m_u; // put back u & v scale
901 if (x * x + (y-m_v) * (y-m_v) > m_u * m_u + m_v * m_v)
902 return (false); // clip against circle, r = sqrt(@)
907 if (x > 1. || x < -1. || y > 1.) // extent
909 if (y > 1. - x || y > 1. + x) // triangle
910 return (false); // clip against triangle
911 x *= m_u; // circle: put back u & v scale
913 if (x * x + (y-m_v) * (y-m_v) > m_u * m_u + m_v * m_v)
914 return (false); // clip against circle
919 sys_error (ERR_WARNING, "Illegal pelem type in pelem_is_point_inside()");