comparison: src/basics.cpp
src/basics.cpp
- changeset 1181
- ca6d0ef9aadb
- parent 1177
- 8661b9237ed5
- child 1305
- 31627acdd4b5
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| 1180:2005e4147ad6 | 1181:ca6d0ef9aadb |
|---|---|
| 278 lines.append(QLineF {QPointF {x0, z0}, QPointF {x1, z1}}); | 278 lines.append(QLineF {QPointF {x0, z0}, QPointF {x1, z1}}); |
| 279 } | 279 } |
| 280 | 280 |
| 281 return lines; | 281 return lines; |
| 282 } | 282 } |
| 283 | |
| 284 /* | |
| 285 * Computes the shortest distance from a point to a rectangle. | |
| 286 * | |
| 287 * The code originates from the Unity3D wiki, and was translated from C# to Qt by me (Teemu Piippo): | |
| 288 * | |
| 289 * Original code: | |
| 290 * http://wiki.unity3d.com/index.php/Distance_from_a_point_to_a_rectangle | |
| 291 * | |
| 292 * Copyright 2013 Philip Peterson. | |
| 293 * | |
| 294 * Permission is hereby granted, free of charge, to any person obtaining a copy | |
| 295 * of this software and associated documentation files (the "Software"), to | |
| 296 * deal in the Software without restriction, including without limitation the | |
| 297 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or | |
| 298 * sell copies of the Software, and to permit persons to whom the Software is | |
| 299 * furnished to do so, subject to the following conditions: | |
| 300 * | |
| 301 * The above copyright notice and this permission notice shall be included in | |
| 302 * all copies or substantial portions of the Software. | |
| 303 * | |
| 304 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
| 305 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
| 306 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
| 307 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
| 308 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
| 309 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS | |
| 310 * IN THE SOFTWARE. | |
| 311 */ | |
| 312 qreal distanceFromPointToRectangle(const QPointF& point, const QRectF& rectangle) | |
| 313 { | |
| 314 // Calculate a distance between a point and a rectangle. | |
| 315 // The area around/in the rectangle is defined in terms of | |
| 316 // several regions: | |
| 317 // | |
| 318 // O--x | |
| 319 // | | |
| 320 // y | |
| 321 // | |
| 322 // | |
| 323 // I | II | III | |
| 324 // ======+==========+====== --yMin | |
| 325 // VIII | IX (in) | IV | |
| 326 // ======+==========+====== --yMax | |
| 327 // VII | VI | V | |
| 328 // | |
| 329 // | |
| 330 // Note that the +y direction is down because of Unity's GUI coordinates. | |
| 331 | |
| 332 if (point.x() < rectangle.left()) | |
| 333 { | |
| 334 // Region I, VIII, or VII | |
| 335 if (point.y() < rectangle.top()) // I | |
| 336 return QLineF {point, rectangle.topLeft()}.length(); | |
| 337 else if (point.y() > rectangle.bottom()) // VII | |
| 338 return QLineF {point, rectangle.bottomLeft()}.length(); | |
| 339 else // VIII | |
| 340 return rectangle.left() - point.x(); | |
| 341 } | |
| 342 else if (point.x() > rectangle.right()) | |
| 343 { | |
| 344 // Region III, IV, or V | |
| 345 if (point.y() < rectangle.top()) // III | |
| 346 return QLineF {point, rectangle.topRight()}.length(); | |
| 347 else if (point.y() > rectangle.bottom()) // V | |
| 348 return QLineF {point, rectangle.bottomRight()}.length(); | |
| 349 else // IV | |
| 350 return point.x() - rectangle.right(); | |
| 351 } | |
| 352 else | |
| 353 { | |
| 354 // Region II, IX, or VI | |
| 355 if (point.y() < rectangle.top()) // II | |
| 356 return rectangle.top() - point.y(); | |
| 357 else if (point.y() > rectangle.bottom()) // VI | |
| 358 return point.y() - rectangle.bottom(); | |
| 359 else // IX | |
| 360 return 0; | |
| 361 } | |
| 362 } |
