1 /**
2 * \file
3 * \brief Horizontal and Vertical Line Segment
4 *
5 * Copyright 2008 Marco Cecchetti <mrcekets at gmail.com>
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it either under the terms of the GNU Lesser General Public
9 * License version 2.1 as published by the Free Software Foundation
10 * (the "LGPL") or, at your option, under the terms of the Mozilla
11 * Public License Version 1.1 (the "MPL"). If you do not alter this
12 * notice, a recipient may use your version of this file under either
13 * the MPL or the LGPL.
14 *
15 * You should have received a copy of the LGPL along with this library
16 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 * You should have received a copy of the MPL along with this library
19 * in the file COPYING-MPL-1.1
20 *
21 * The contents of this file are subject to the Mozilla Public License
22 * Version 1.1 (the "License"); you may not use this file except in
23 * compliance with the License. You may obtain a copy of the License at
24 * http://www.mozilla.org/MPL/
25 *
26 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
27 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
28 * the specific language governing rights and limitations.
29 */
32 #ifndef _2GEOM_HVLINESEGMENT_H_
33 #define _2GEOM_HVLINESEGMENT_H_
36 #include <2geom/bezier-curve.h>
39 namespace Geom
40 {
42 class HLineSegment : public Curve
43 {
44 public:
45 HLineSegment()
46 {}
48 HLineSegment(Coord _x0, Coord _x1, Coord _y)
49 : m_line_seg(Point(_x0, _y), Point(_x1, _y))
50 {
51 }
53 HLineSegment(Point const& _p, double _length)
54 : m_line_seg(_p, Point(_p[X] + _length, _p[Y]))
55 {
56 }
58 HLineSegment(Point const& _p0, Point const& _p1)
59 : m_line_seg(_p0, _p1)
60 {
61 if ( _p0[Y] != _p1[Y] )
62 {
63 THROW_RANGEERROR("HLineSegment::HLineSegment passed points should "
64 "have the same Y value");
65 }
66 }
68 Curve* duplicate() const
69 {
70 return new HLineSegment(*this);
71 }
73 bool isDegenerate() const
74 {
75 return m_line_seg.isDegenerate();
76 }
78 Point initialPoint() const
79 {
80 return m_line_seg.initialPoint();
81 }
83 Point finalPoint() const
84 {
85 return m_line_seg.finalPoint();
86 }
88 Coord getY()
89 {
90 return initialPoint()[Y];
91 }
93 void setInitial(Point _p)
94 {
95 m_line_seg.setInitial( Point(_p[X], initialPoint()[Y]) );
96 }
98 void setFinal(Point _p)
99 {
100 m_line_seg.setFinal( Point(_p[X], finalPoint()[Y]) );
101 }
103 void setX0(Coord _x)
104 {
105 m_line_seg.setInitial( Point(_x, initialPoint()[Y]) );
106 }
108 void setX1(Coord _x)
109 {
110 m_line_seg.setFinal( Point(_x, finalPoint()[Y]) );
111 }
113 void setY(Coord _y)
114 {
115 m_line_seg.setInitial( Point(initialPoint()[X], _y) );
116 m_line_seg.setFinal( Point(finalPoint()[X], _y) );
117 }
119 virtual OptRect boundsFast() const
120 {
121 return boundsExact();
122 }
124 virtual OptRect boundsExact() const
125 {
126 return Rect( initialPoint(), finalPoint() );
127 }
129 virtual OptRect boundsLocal(OptInterval i, unsigned deg) const
130 {
131 return m_line_seg.boundsLocal(i, deg);
132 }
134 int winding(Point p) const
135 {
136 return m_line_seg.winding(p);
137 }
139 std::vector<double>
140 roots(double v, Dim2 d) const
141 {
142 if (d < 0 || d > 1)
143 {
144 THROW_RANGEERROR("dimension argument out of range");
145 }
146 std::vector<double> result;
147 if (d == X)
148 {
149 if ( v >= initialPoint()[X] && v <= finalPoint()[X] )
150 {
151 double t = 0;
152 if (!isDegenerate())
153 t = (v - initialPoint()[X]) / (finalPoint()[X] - initialPoint()[X]);
154 result.push_back(t);
155 }
156 }
157 else
158 {
159 if (v == initialPoint()[Y])
160 {
161 if (!isDegenerate())
162 THROW_INFINITESOLUTIONS(0);
163 result.push_back(0);
164 }
165 }
166 return result;
167 }
169 double nearestPoint( Point const& p, double from = 0, double to = 1 ) const
170 {
171 if ( from > to ) std::swap(from, to);
172 double xfrom = pointAt(from)[X];
173 double xto = pointAt(to)[X];
174 if ( xfrom > xto )
175 {
176 std::swap(xfrom, xto);
177 std::swap(from, to);
178 }
179 if ( p[X] > xfrom && p[X] < xto )
180 {
181 return (p[X] - initialPoint()[X]) / (finalPoint()[X] - initialPoint()[X]);
182 }
183 else if ( p[X] <= xfrom )
184 return from;
185 else
186 return to;
187 }
189 std::pair<HLineSegment, HLineSegment> subdivide(Coord t) const
190 {
191 std::pair<HLineSegment, HLineSegment> result;
192 Point p = pointAt(t);
193 result.first.setInitial(initialPoint());
194 result.first.setFinal(p);
195 result.second.setInitial(p);
196 result.second.setFinal(finalPoint());
197 return result;
198 }
200 Curve* portion(double f, double t) const
201 {
202 Point ip = pointAt(f);
203 Point ep = pointAt(t);
204 return new HLineSegment(ip[X], ep[X], ip[Y]);
205 }
207 Curve* reverse() const
208 {
209 return
210 new HLineSegment(finalPoint()[X], initialPoint()[X], initialPoint()[Y]);
211 }
213 Curve* transformed(Matrix const & m) const
214 {
215 Point ip = initialPoint() * m;
216 Point ep = finalPoint() * m;
217 if (m.onlyScaleAndTranslation()) {
218 return new HLineSegment(ip[X], ep[X], ip[Y]);
219 } else {
220 return new LineSegment(ip, ep);
221 }
222 }
224 Curve* derivative() const
225 {
226 double x = finalPoint()[X] - initialPoint()[X];
227 return new HLineSegment(x, x, 0);
228 }
230 Point pointAt(double t) const
231 {
232 if ( t < 0 || t > 1 )
233 THROW_RANGEERROR("domain parameter out of range");
234 double x = initialPoint()[X] + t * (finalPoint()[X] - initialPoint()[X]);
235 return Point(x, initialPoint()[Y]);
236 }
238 double valueAt(double t, Dim2 d) const
239 {
240 if (d < 0 || d > 1)
241 {
242 THROW_RANGEERROR("dimension argument out of range");
243 }
244 if ( t < 0 || t > 1 )
245 THROW_RANGEERROR("domain parameter out of range");
247 if (d == Y) return initialPoint()[Y];
249 return initialPoint()[X] + t * (finalPoint()[X] - initialPoint()[X]);
250 }
252 std::vector<Point> pointAndDerivatives(Coord t, unsigned n) const
253 {
254 std::vector<Point> result;
255 result.push_back(pointAt(t));
256 if (n > 0)
257 {
258 double x = finalPoint()[X] - initialPoint()[X];
259 result.push_back( Point(x, 0) );
260 }
261 if (n > 1)
262 {
263 /* higher order derivatives are zero,
264 * so the other n-1 vector elements are (0,0) */
265 result.insert( result.end(), n-1, Point(0, 0) );
266 }
267 return result;
268 }
270 D2<SBasis> toSBasis() const
271 {
272 return m_line_seg.toSBasis();
273 }
275 private:
276 LineSegment m_line_seg;
278 }; // end class HLineSegment
281 class VLineSegment : public Curve
282 {
283 public:
284 VLineSegment()
285 {}
287 VLineSegment(Coord _x, Coord _y0, Coord _y1)
288 : m_line_seg(Point(_x, _y0), Point(_x, _y1))
289 {
290 }
292 VLineSegment(Point const& _p, double _length)
293 : m_line_seg(_p, Point(_p[X], _p[Y] + _length))
294 {
295 }
297 VLineSegment(Point const& _p0, Point const& _p1)
298 : m_line_seg(_p0, _p1)
299 {
300 if ( _p0[X] != _p1[X] )
301 {
302 THROW_RANGEERROR("VLineSegment::VLineSegment passed points should "
303 "have the same X value");
304 }
305 }
307 Curve* duplicate() const
308 {
309 return new VLineSegment(*this);
310 }
312 bool isDegenerate() const
313 {
314 return m_line_seg.isDegenerate();
315 }
317 Point initialPoint() const
318 {
319 return m_line_seg.initialPoint();
320 }
322 Point finalPoint() const
323 {
324 return m_line_seg.finalPoint();
325 }
327 Coord getX()
328 {
329 return initialPoint()[X];
330 }
332 void setInitial(Point _p)
333 {
334 m_line_seg.setInitial( Point(initialPoint()[X], _p[Y]) );
335 }
337 void setFinal(Point _p)
338 {
339 m_line_seg.setFinal( Point(finalPoint()[X], _p[Y]) );
340 }
342 void setY0(Coord _y)
343 {
344 m_line_seg.setInitial( Point(initialPoint()[X], _y) );
345 }
347 void setY1(Coord _y)
348 {
349 m_line_seg.setFinal( Point(finalPoint()[Y], _y) );
350 }
352 void setX(Coord _x)
353 {
354 m_line_seg.setInitial( Point(_x, initialPoint()[Y]) );
355 m_line_seg.setFinal( Point(_x, finalPoint()[Y]) );
356 }
358 virtual OptRect boundsFast() const
359 {
360 return boundsExact();
361 }
363 virtual OptRect boundsExact() const
364 {
365 return Rect( initialPoint(), finalPoint() );
366 }
368 virtual OptRect boundsLocal(OptInterval i, unsigned deg) const
369 {
370 return m_line_seg.boundsLocal(i, deg);
371 }
373 int winding(Point p) const
374 {
375 return m_line_seg.winding(p);
376 }
378 std::vector<double>
379 roots(double v, Dim2 d) const
380 {
381 if (d < 0 || d > 1)
382 {
383 THROW_RANGEERROR("dimension argument out of range");
384 }
385 std::vector<double> result;
386 if (d == Y)
387 {
388 if ( v >= initialPoint()[Y] && v <= finalPoint()[Y] )
389 {
390 double t = 0;
391 if (!isDegenerate())
392 t = (v - initialPoint()[Y]) / (finalPoint()[Y] - initialPoint()[Y]);
393 result.push_back(t);
394 }
395 }
396 else
397 {
398 if (v == initialPoint()[X])
399 {
400 if (!isDegenerate())
401 THROW_INFINITESOLUTIONS(0);
402 result.push_back(0);
403 }
404 }
405 return result;
406 }
408 double nearestPoint( Point const& p, double from = 0, double to = 1 ) const
409 {
410 if ( from > to ) std::swap(from, to);
411 double yfrom = pointAt(from)[Y];
412 double yto = pointAt(to)[Y];
413 if (yfrom > yto)
414 {
415 std::swap(yfrom, yto);
416 std::swap(from, to);
417 }
418 if ( p[Y] > yfrom && p[Y] < yto )
419 {
420 return (p[Y] - initialPoint()[Y]) / (finalPoint()[Y] - initialPoint()[Y]);
421 }
422 else if ( p[Y] <= yfrom )
423 return from;
424 else
425 return to;
426 }
428 std::pair<VLineSegment, VLineSegment> subdivide(Coord t) const
429 {
430 std::pair<VLineSegment, VLineSegment> result;
431 Point p = pointAt(t);
432 result.first.setInitial(initialPoint());
433 result.first.setFinal(p);
434 result.second.setInitial(p);
435 result.second.setFinal(finalPoint());
436 return result;
437 }
439 Curve* portion(double f, double t) const
440 {
441 Point ip = pointAt(f);
442 Point ep = pointAt(t);
443 return new VLineSegment(ip[X], ip[Y], ep[Y]);
444 }
446 Curve* reverse() const
447 {
448 return
449 new VLineSegment(initialPoint()[X], finalPoint()[Y], initialPoint()[Y]);
450 }
452 Curve* transformed(Matrix const & m) const
453 {
454 Point ip = initialPoint() * m;
455 Point ep = finalPoint() * m;
456 if (m.onlyScaleAndTranslation()) {
457 return new VLineSegment(ip[X], ip[Y], ep[Y]);
458 } else {
459 return new LineSegment(ip, ep);
460 }
461 }
463 Curve* derivative() const
464 {
465 double y = finalPoint()[Y] - initialPoint()[Y];
466 return new VLineSegment(0, y, y);
467 }
469 Point pointAt(double t) const
470 {
471 if ( t < 0 || t > 1 )
472 THROW_RANGEERROR("domain parameter out of range");
473 double y = initialPoint()[Y] + t * (finalPoint()[Y] - initialPoint()[Y]);
474 return Point(initialPoint()[X], y);
475 }
477 double valueAt(double t, Dim2 d) const
478 {
479 if (d < 0 || d > 1)
480 {
481 THROW_RANGEERROR("dimension argument out of range");
482 }
483 if ( t < 0 || t > 1 )
484 THROW_RANGEERROR("domain parameter out of range");
486 if (d == X) return initialPoint()[X];
488 return initialPoint()[Y] + t * (finalPoint()[Y] - initialPoint()[Y]);
489 }
491 std::vector<Point> pointAndDerivatives(Coord t, unsigned n) const
492 {
493 std::vector<Point> result;
494 result.push_back(pointAt(t));
495 if (n > 0)
496 {
497 double y = finalPoint()[Y] - initialPoint()[Y];
498 result.push_back( Point(0, y) );
499 }
500 if (n > 1)
501 {
502 /* higher order derivatives are zero,
503 * so the other n-1 vector elements are (0,0) */
504 result.insert( result.end(), n-1, Point(0, 0) );
505 }
506 return result;
507 }
509 D2<SBasis> toSBasis() const
510 {
511 return m_line_seg.toSBasis();
512 }
514 private:
515 LineSegment m_line_seg;
517 }; // end class VLineSegment
521 } // end namespace Geom
524 #endif // _2GEOM_HVLINESEGMENT_H_
527 /*
528 Local Variables:
529 mode:c++
530 c-file-style:"stroustrup"
531 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
532 indent-tabs-mode:nil
533 fill-column:99
534 End:
535 */
536 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :