demos/qtdemo/guide.cpp

   1 /****************************************************************************
   2 **
   3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
   4 ** Contact: Qt Software Information (qt-info@nokia.com)
   5 **
   6 ** This file is part of the demonstration applications of the Qt Toolkit.
   7 **
   8 ** $QT_BEGIN_LICENSE:LGPL$
   9 ** No Commercial Usage
  10 ** This file contains pre-release code and may not be distributed.
  11 ** You may use this file in accordance with the terms and conditions
  12 ** contained in the either Technology Preview License Agreement or the
  13 ** Beta Release License Agreement.
  14 **
  15 ** GNU Lesser General Public License Usage
  16 ** Alternatively, this file may be used under the terms of the GNU Lesser
  17 ** General Public License version 2.1 as published by the Free Software
  18 ** Foundation and appearing in the file LICENSE.LGPL included in the
  19 ** packaging of this file.  Please review the following information to
  20 ** ensure the GNU Lesser General Public License version 2.1 requirements
  21 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
  22 **
  23 ** In addition, as a special exception, Nokia gives you certain
  24 ** additional rights. These rights are described in the Nokia Qt LGPL
  25 ** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
  26 ** package.
  27 **
  28 ** GNU General Public License Usage
  29 ** Alternatively, this file may be used under the terms of the GNU
  30 ** General Public License version 3.0 as published by the Free Software
  31 ** Foundation and appearing in the file LICENSE.GPL included in the
  32 ** packaging of this file.  Please review the following information to
  33 ** ensure the GNU General Public License version 3.0 requirements will be
  34 ** met: http://www.gnu.org/copyleft/gpl.html.
  35 **
  36 ** If you are unsure which license is appropriate for your use, please
  37 ** contact the sales department at qt-sales@nokia.com.
  38 ** $QT_END_LICENSE$
  39 **
  40 ****************************************************************************/
  41
  42 #include <cmath>
  43 #include "guide.h"
  44 #include "colors.h"
  45
  46 Guide::Guide(Guide *follows)
  47 {
  48     this->scaleX = 1.0;
  49     this->scaleY = 1.0;
  50
  51     if (follows){
  52         while (follows->nextGuide != follows->firstGuide) // append to end
  53             follows = follows->nextGuide;
  54
  55         follows->nextGuide = this;
  56         this->prevGuide = follows;
  57         this->firstGuide = follows->firstGuide;
  58         this->nextGuide = follows->firstGuide;
  59         this->startLength = int(follows->startLength + follows->length()) + 1;
  60     }
  61     else{
  62         this->prevGuide = this;
  63         this->firstGuide = this;
  64         this->nextGuide = this;
  65         this->startLength = 0;
  66     }
  67 }
  68
  69 void Guide::setScale(float scaleX, float scaleY, bool all)
  70 {
  71     this->scaleX = scaleX;
  72     this->scaleY = scaleY;
  73
  74     if (all){
  75         Guide *next = this->nextGuide;
  76         while(next != this){
  77             next->scaleX = scaleX;
  78             next->scaleY = scaleY;
  79             next = next->nextGuide;
  80         }
  81     }
  82 }
  83
  84 void Guide::setFence(const QRectF &fence, bool all)
  85 {
  86     this->fence = fence;
  87
  88     if (all){
  89         Guide *next = this->nextGuide;
  90         while(next != this){
  91             next->fence = fence;
  92             next = next->nextGuide;
  93         }
  94     }
  95 }
  96
  97 Guide::~Guide()
  98 {
  99     if (this != this->nextGuide && this->nextGuide != this->firstGuide)
 100         delete this->nextGuide;
 101 }
 102
 103 float Guide::lengthAll()
 104 {
 105     float len = length();
 106     Guide *next = this->nextGuide;
 107     while(next != this){
 108         len += next->length();
 109         next = next->nextGuide;
 110     }
 111     return len;
 112 }
 113
 114 void Guide::move(DemoItem *item, QPointF &dest, float moveSpeed)
 115 {
 116     QLineF walkLine(item->getGuidedPos(), dest);
 117     if (moveSpeed >= 0 && walkLine.length() > moveSpeed){
 118         // The item is too far away from it's destination point.
 119         // So we choose to move it towards it instead.
 120         float dx = walkLine.dx();
 121         float dy = walkLine.dy();
 122
 123         if (qAbs(dx) > qAbs(dy)){
 124             // walk along x-axis
 125             if (dx != 0){
 126                 float d = moveSpeed * dy / qAbs(dx);
 127                 float s = dx > 0 ? moveSpeed : -moveSpeed;
 128                 dest.setX(item->getGuidedPos().x() + s);
 129                 dest.setY(item->getGuidedPos().y() + d);
 130             }
 131         }
 132         else{
 133             // walk along y-axis
 134             if (dy != 0){
 135                 float d = moveSpeed * dx / qAbs(dy);
 136                 float s = dy > 0 ? moveSpeed : -moveSpeed;
 137                 dest.setX(item->getGuidedPos().x() + d);
 138                 dest.setY(item->getGuidedPos().y() + s);
 139             }
 140         }
 141     }
 142
 143     item->setGuidedPos(dest);
 144 }