Shamusworld >> Repos - architektonas/blob - src/base/rs_infoarea.cpp

   1 /****************************************************************************
   2 ** $Id: rs_infoarea.cpp 1892 2004-07-09 23:54:59Z andrew $
   3 **
   4 ** Copyright (C) 2001-2003 RibbonSoft. All rights reserved.
   5 **
   6 ** This file is part of the qcadlib Library project.
   7 **
   8 ** This file may be distributed and/or modified under the terms of the
   9 ** GNU General Public License version 2 as published by the Free Software
  10 ** Foundation and appearing in the file LICENSE.GPL included in the
  11 ** packaging of this file.
  12 **
  13 ** Licensees holding valid qcadlib Professional Edition licenses may use
  14 ** this file in accordance with the qcadlib Commercial License
  15 ** Agreement provided with the Software.
  16 **
  17 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
  18 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  19 **
  20 ** See http://www.ribbonsoft.com for further details.
  21 **
  22 ** Contact info@ribbonsoft.com if any conditions of this licensing are
  23 ** not clear to you.
  24 **
  25 **********************************************************************/
  26
  27 #include "rs_infoarea.h"
  28
  29 #include "rs_math.h"
  30 #include "rs_debug.h"
  31
  32 /**
  33  * Constructor.
  34  */
  35 RS_InfoArea::RS_InfoArea()
  36 {
  37 }
  38
  39 /**
  40  * Destructor.
  41  */
  42 RS_InfoArea::~RS_InfoArea()
  43 {
  44 }
  45
  46 /**
  47  * Adds a point to the internal list
  48  *
  49  * @param p co-ordinate of the point
  50  */
  51 void RS_InfoArea::addPoint(const Vector & p)
  52 {
  53         if (thePoints.empty())
  54                 baseY = p.y;
  55
  56         thePoints.append(p);
  57 }
  58
  59 /**
  60  * Resets the points.
  61  */
  62 void RS_InfoArea::reset()
  63 {
  64         thePoints.clear();
  65         area = 0.0;
  66         circumference = 0.0;
  67 }
  68
  69 /**
  70  * Closes the polygon if it is not closed already.
  71  */
  72 void RS_InfoArea::close()
  73 {
  74         if (isValid() && isClosed() == false)
  75         {
  76                 thePoints.append(thePoints.first());
  77
  78                 RS_DEBUG->print("RS_InfoArea::close: closed");
  79         }
  80 }
  81
  82 /**
  83  * @retval true If the area is closed (i.e. start point and end point are
  84  *   identical)
  85  * @retval false Otherwise.
  86  */
  87 bool RS_InfoArea::isClosed()
  88 {
  89         return (thePoints.first().distanceTo(thePoints.last()) < 1.0e-4);
  90 }
  91
  92 /**
  93  * @retval true If the area is defined (i.e. there are at least 3 points)
  94  * @retval false If there are only two or less points.
  95  */
  96 bool RS_InfoArea::isValid()
  97 {
  98         RS_DEBUG->print("RS_InfoArea::isValid: count: %d", thePoints.count());
  99         return (thePoints.count() > 2);
 100 }
 101
 102 /**
 103  * Calculates the area and the circumference of the area.
 104  */
 105 void RS_InfoArea::calculate()
 106 {
 107         area = 0.0;
 108         circumference = 0.0;
 109         Vector ptFirst;
 110         Vector p1;
 111         Vector p2;
 112
 113         // at least 3 points needed for an area
 114         if (isValid())
 115         {
 116                 ptFirst = thePoints.last();
 117                 thePoints.pop_back();
 118
 119                 p1 = ptFirst;
 120
 121                 while (!thePoints.empty())
 122                 {
 123                         p2 = thePoints.last();
 124                         thePoints.pop_back();
 125
 126                         area += calcSubArea(p1, p2);
 127                         circumference += p1.distanceTo(p2);
 128                         //if (p1 != ptFirst) {
 129                         //      delete p1;
 130                         //}
 131                         p1 = p2;
 132                 }
 133
 134                 area += calcSubArea(p1, ptFirst);
 135                 circumference += p1.distanceTo(ptFirst);
 136                 //delete p1;
 137                 //delete ptFirst;
 138         }
 139
 140         //thePoints.clear();
 141         area = fabs(area);
 142 }
 143
 144 double RS_InfoArea::getArea()
 145 {
 146         return area;
 147 }
 148
 149 double RS_InfoArea::getCircumference()
 150 {
 151         return circumference;
 152 }
 153
 154 int RS_InfoArea::count()
 155 {
 156         return thePoints.count();
 157 }
 158
 159 /**
 160  * Calculates a sub area.
 161  *
 162  * @param p1 first point
 163  * @param p2 second point
 164  */
 165 double RS_InfoArea::calcSubArea(const Vector & p1, const Vector & p2)
 166 {
 167         double width = p2.x - p1.x;
 168         double height = (p1.y - baseY) + (p2.y - baseY);
 169
 170         return (width * height) / 2.0;
 171 }
 172
 173 /*! Calculates a distance
 174     \param _p1 first point
 175     \param _p2 second point
 176 */
 177 /*double
 178 RS_InfoArea::calcDistance(Vector *_p1, Vector *_p2)
 179 {
 180         return mtGetDistance(_p1->getX(), _p1->getY(), _p2->getX(), _p2->getY());
 181 }*/