workspace/kcontrol/randr/layoutmanager.cpp

   1 /*
   2  * Copyright (c) 2007      Gustavo Pichorim Boiko <gustavo.boiko@kdemail.net>
   3  *
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License as published by
   6  *  the Free Software Foundation; either version 2 of the License, or
   7  *  (at your option) any later version.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License
  15  *  along with this program; if not, write to the Free Software
  16  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17  */
  18
  19 #include "layoutmanager.h"
  20 #include "randr.h"
  21 #include "randrscreen.h"
  22 #include "randroutput.h"
  23 #include "outputgraphicsitem.h"
  24
  25 #include <QGraphicsScene>
  26 #include <cmath>
  27 #include <math.h>
  28
  29 LayoutManager::LayoutManager(RandRScreen *screen, QGraphicsScene *scene)
  30 : QObject(screen)
  31 {
  32         m_screen = screen;
  33         m_scene = scene;
  34 }
  35
  36 LayoutManager::~LayoutManager()
  37 {
  38 }
  39
  40 void LayoutManager::slotAdjustOutput(OutputGraphicsItem *output)
  41 {
  42         QPointF p = output->pos();
  43         float nearest = m_scene->width() * m_scene->height();
  44         OutputGraphicsItem *selected = NULL;
  45
  46         OutputGraphicsItem *mouseGrabber = dynamic_cast<OutputGraphicsItem*>(m_scene->mouseGrabberItem());
  47         // find the nearest item
  48         QList<QGraphicsItem *> itemList = m_scene->items();
  49
  50         foreach(QGraphicsItem *current, itemList)
  51         {
  52                 OutputGraphicsItem *cur = dynamic_cast<OutputGraphicsItem*>(current);
  53                 if (cur == output || cur == mouseGrabber)
  54                         continue;
  55
  56                 QPointF pos = cur->pos();
  57                 float distance = (p.x() - pos.x())*(p.x()-pos.x()) + (p.y() - pos.y())*(p.y() - pos.y());
  58                 if (distance <=nearest)
  59                 {
  60                         nearest = distance;
  61                         selected  = cur;
  62                 }
  63         }
  64
  65         if (selected)
  66         {
  67                 // find in which side this
  68                 QRectF s = selected->boundingRect();
  69                 QRectF i = output->boundingRect();
  70
  71                 s.translate(selected->scenePos());
  72                 i.translate(output->scenePos());
  73
  74                 // calculate the distances
  75                 float top = fabsf(i.top() - s.bottom());
  76                 float bottom = fabsf(i.bottom() - s.top());
  77                 float left = fabsf(i.left() - s.right());
  78                 float right = fabsf(i.right() - s.left());
  79
  80                 // choose top
  81                 if (top <= bottom && top <= left && top <= right)
  82                 {
  83                         output->setTop(selected);
  84                         selected->setBottom(output);
  85                 }
  86                 // choose bottom
  87                 else if (bottom < top && bottom <= left && bottom <= right)
  88                 {
  89                         output->setBottom(selected);
  90                         selected->setTop(output);
  91                 }
  92                 // choose left
  93                 else if (left < top && left < bottom && left <= right)
  94                 {
  95                         output->setLeft(selected);
  96                         selected->setRight(output);
  97                 }
  98                 // choose right
  99                 else
 100                 {
 101                         output->setRight(selected);
 102                         selected->setLeft(output);
 103                 }
 104         }
 105
 106         // now visit all the outputs on the screen to adjust their positions
 107         // starting by the item selected to be the parent of the current item
 108         QList<OutputGraphicsItem *> visitedList;
 109
 110         // FIXME: after adjusting the scene, we have to translate everything back to
 111         // the 0,0 position so that everything is onscreen
 112         output->setPos(0,0);
 113         // call a recursive function to adjust the outputs
 114         adjustScene(output, visitedList);
 115 }
 116
 117 void LayoutManager::adjustScene(OutputGraphicsItem *current, QList<OutputGraphicsItem*> &visited)
 118 {
 119         visited.append(current);
 120
 121         OutputGraphicsItem *item;
 122         item = current->left();
 123         if (item && visited.indexOf(item) == -1)
 124         {
 125         item->setPos(current->x() - item->boundingRect().width(), current->y());
 126         adjustScene(item, visited);
 127         }
 128
 129         item = current->right();
 130         if (item && visited.indexOf(item) == -1)
 131         {
 132         item->setPos(current->x() + current->boundingRect().width(), current->y());
 133         adjustScene(item, visited);
 134         }
 135
 136         item = current->top();
 137         if (item && visited.indexOf(item) == -1)
 138         {
 139         item->setPos(current->x(), current->y() - item->boundingRect().height());
 140         adjustScene(item, visited);
 141         }
 142
 143         item = current->bottom();
 144         if (item && visited.indexOf(item) == -1)
 145         {
 146         item->setPos(current->x(), current->y() + current->boundingRect().height());
 147         adjustScene(item, visited);
 148         }
 149
 150 }