00001 /*---------------------------------------------------------------------+ 00002 | Library QgarLib, graphics analysis and recognition | 00003 | Copyright (C) 2002 Qgar Project, LORIA | 00004 | | 00005 | This library is free software; you can redistribute it and/or | 00006 | modify it under the terms of the GNU Lesser General Public | 00007 | License version 2.1, as published by the Free Software Foundation. | 00008 | | 00009 | This library is distributed in the hope that it will be useful, | 00010 | but WITHOUT ANY WARRANTY; without even the implied warranty of | 00011 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | 00012 | See the GNU Lesser General Public License for more details. | 00013 | | 00014 | The GNU Lesser General Public License is included in the file | 00015 | LICENSE.LGPL, in the root directory of the Qgar packaging. See | 00016 | http://www.gnu.org/licenses/lgpl.html for the terms of the licence. | 00017 | To receive a paper copy, write to the Free Software Foundation, | 00018 | Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. | 00019 | | 00020 | Contact Project Qgar for any information: | 00021 | LORIA - équipe Qgar | 00022 | B.P. 239, 54506 Vandoeuvre-lès-Nancy Cedex, France | 00023 | email: qgar-contact@loria.fr | 00024 | http://www.qgar.org/ | 00025 *---------------------------------------------------------------------*/ 00026 00027 00028 /** 00029 * @file _QGAR_segment.TCC 00030 * @brief Implementation of functions which compute segments. 00031 * 00032 * Computational geometry equations can be found in the FAQ section 00033 * of comp.graphics.algorithms and are based on 00034 * [<a href="Bibliography.html#Kirk-1992">Kirk, 1992</a>], 00035 * pages 199-202, and 00036 * [<a href="Bibliography.html#ORourke-1994">O'Rourke, 1994</a>], 00037 * pages 249-51. 00038 * 00039 * @author <a href="mailto:qgar-develop@loria.fr?subject=Qgar fwd Gérald Masini">Gérald Masini</a> 00040 * @date February 03, 2005 19:18 00041 * @since Qgar 2.2 00042 */ 00043 00044 00045 00046 namespace qgar 00047 { 00048 00049 00050 // ------------------------------------------------------------------- 00051 // P R O J E C T I O N S 00052 // ------------------------------------------------------------------- 00053 00054 00055 // SEGMENT PERPENDICULAR TO A GIVEN SEGMENT 00056 // ======================================== 00057 // The source of the new segment is the given point, the target 00058 // is the orthogonal projection of the given point onto the line 00059 // supporting the given segment 00060 00061 00062 template <class T> 00063 inline GenSegment<double> 00064 qgPerpendicular(const GenPoint<T>& aPt, const GenSegment<T>& aSeg) 00065 { 00066 return GenSegment<double>(static_cast< GenPoint<double> >(aPt), 00067 qgProject(aPt,aSeg)); 00068 } 00069 00070 00071 // SEGMENT PERPENDICULAR TO A GIVEN Qgar SEGMENT 00072 // ============================================= 00073 00074 00075 template <class T> 00076 inline GenQgarSegment<double> 00077 qgPerpendicular(const GenPoint<T>& aPt, const GenQgarSegment<T>& aQSeg) 00078 { 00079 return GenQgarSegment<double>(static_cast< GenPoint<double> >(aPt), 00080 qgProject(aPt,aQSeg), 00081 aQSeg.color(), 00082 aQSeg.thickness(), 00083 aQSeg.outLine()); 00084 } 00085 00086 00087 // ------------------------------------------------------------------- 00088 00089 00090 } // namespace qgar