src/libs/alm/RowColumnManager.cpp

   1 /*
   2  * Copyright 2011, Haiku, Inc. All rights reserved.
   3  * Copyright 2011, Clemens Zeidler <haiku@clemens-zeidler.de>
   4  * Distributed under the terms of the MIT License.
   5  */
   6
   7
   8 #include "RowColumnManager.h"
   9
  10
  11 #include <LayoutItem.h>
  12
  13
  14 using namespace LinearProgramming;
  15
  16
  17 namespace BALM {
  18
  19
  20 RowColumnManager::RowColumnManager(LinearSpec* spec)
  21         :
  22         fLinearSpec(spec)
  23 {
  24
  25 }
  26
  27
  28 RowColumnManager::~RowColumnManager()
  29 {
  30         for (int32 i = 0; i < fRows.CountItems(); i++)
  31                 delete fRows.ItemAt(i)->fPrefSizeConstraint;
  32
  33         for (int32 i = 0; i < fColumns.CountItems(); i++)
  34                 delete fColumns.ItemAt(i)->fPrefSizeConstraint;
  35 }
  36
  37
  38 void
  39 RowColumnManager::AddArea(Area* area)
  40 {
  41         Row* row = _FindRowFor(area);
  42         if (row == NULL) {
  43                 row = new Row(fLinearSpec, area->Top(), area->Bottom());
  44                 fRows.AddItem(row);
  45         }
  46         area->fRow = row;
  47         row->fAreas.AddItem(area);
  48
  49         Column* column = _FindColumnFor(area);
  50         if (column == NULL) {
  51                 column = new Column(fLinearSpec, area->Left(), area->Right());
  52                 fColumns.AddItem(column);
  53         }
  54         area->fColumn = column;
  55         column->fAreas.AddItem(area);
  56
  57         _UpdateConstraints(row);
  58         _UpdateConstraints(column);
  59 }
  60
  61
  62 void
  63 RowColumnManager::RemoveArea(Area* area)
  64 {
  65         Row* row = area->fRow;
  66         if (row) {
  67                 row->fAreas.RemoveItem(area);
  68                 area->fRow = NULL;
  69                 if (row->fAreas.CountItems() == 0) {
  70                         fRows.RemoveItem(row);
  71                         delete row;
  72                 } else
  73                         _UpdateConstraints(row);
  74         }
  75
  76         Column* column = area->fColumn;
  77         if (column) {
  78                 column->fAreas.RemoveItem(area);
  79                 area->fColumn = NULL;
  80                 if (column->fAreas.CountItems() == 0) {
  81                         fColumns.RemoveItem(column);
  82                         delete column;
  83                 } else
  84                         _UpdateConstraints(column);
  85         }
  86 }
  87
  88
  89 void
  90 RowColumnManager::UpdateConstraints()
  91 {
  92         for (int32 i = 0; i < fRows.CountItems(); i++)
  93                 _UpdateConstraints(fRows.ItemAt(i));
  94         for (int32 i = 0; i < fColumns.CountItems(); i++)
  95                 _UpdateConstraints(fColumns.ItemAt(i));
  96 }
  97
  98
  99 void
 100 RowColumnManager::TabsChanged(Area* area)
 101 {
 102         RemoveArea(area);
 103         AddArea(area);
 104 }
 105
 106
 107 Row*
 108 RowColumnManager::_FindRowFor(Area* area)
 109 {
 110         for (int32 i = 0; i < fRows.CountItems(); i++) {
 111                 Row* row = fRows.ItemAt(i);
 112                 if (row->fTop.Get() == area->Top()
 113                         && row->fBottom.Get() == area->Bottom())
 114                         return row;
 115         }
 116         return NULL;
 117 }
 118
 119
 120 Column*
 121 RowColumnManager::_FindColumnFor(Area* area)
 122 {
 123         for (int32 i = 0; i < fColumns.CountItems(); i++) {
 124                 Column* column = fColumns.ItemAt(i);
 125                 if (column->fLeft.Get() == area->Left()
 126                         && column->fRight.Get() == area->Right())
 127                         return column;
 128         }
 129         return NULL;
 130 }
 131
 132
 133 double
 134 RowColumnManager::_PreferredHeight(Row* row, double& weight)
 135 {
 136         weight = 0;
 137         int nAreas = 0;
 138         double pref = 0;
 139         for (int32 i = 0; i < row->fAreas.CountItems(); i++) {
 140                 BSize prefSize = row->fAreas.ItemAt(i)->Item()->PreferredSize();
 141                 if (prefSize.height <= 0)
 142                         continue;
 143                 nAreas++;
 144                 pref += prefSize.height;
 145                 double negPen = row->fAreas.ItemAt(i)->ShrinkPenalties().height;
 146                 if (negPen > 0)
 147                         weight += negPen;
 148         }
 149         if (nAreas == 0) {
 150                 pref = -1;
 151                 weight = 1;
 152         } else {
 153                 pref /= nAreas;
 154                 weight /= nAreas;
 155         }
 156         return pref;
 157 }
 158
 159
 160 double
 161 RowColumnManager::_PreferredWidth(Column* column, double& weight)
 162 {
 163         weight = 0;
 164         int nAreas = 0;
 165         double pref = 0;
 166         for (int32 i = 0; i < column->fAreas.CountItems(); i++) {
 167                 BSize prefSize = column->fAreas.ItemAt(i)->Item()->PreferredSize();
 168                 if (prefSize.width <= 0)
 169                         continue;
 170                 nAreas++;
 171                 pref += prefSize.width;
 172
 173                 double negPen = column->fAreas.ItemAt(i)->ShrinkPenalties().height;
 174                 if (negPen > 0)
 175                         weight += negPen;
 176         }
 177         if (nAreas == 0) {
 178                 pref = -1;
 179                 weight = 1;
 180         } else {
 181                 pref /= nAreas;
 182                 weight /= nAreas;
 183         }
 184         return pref;
 185 }
 186
 187
 188 void
 189 RowColumnManager::_UpdateConstraints(Row* row)
 190 {
 191         double weight;
 192         double prefSize = _PreferredHeight(row, weight);
 193         if (prefSize >= 0) {
 194                 if (row->fPrefSizeConstraint == NULL) {
 195                         row->fPrefSizeConstraint = fLinearSpec->AddConstraint(1,
 196                                 row->fBottom, -1, row->fTop, kEQ, prefSize, weight, weight);
 197                         row->fPrefSizeConstraint->SetLabel("Pref Height");
 198                 } else {
 199                         row->fPrefSizeConstraint->SetRightSide(prefSize);
 200                         row->fPrefSizeConstraint->SetPenaltyNeg(weight);
 201                         row->fPrefSizeConstraint->SetPenaltyPos(weight);
 202                 }
 203         } else {
 204                 delete row->fPrefSizeConstraint;
 205                 row->fPrefSizeConstraint = NULL;
 206         }
 207 }
 208
 209
 210 void
 211 RowColumnManager::_UpdateConstraints(Column* column)
 212 {
 213         double weight;
 214         double prefSize = _PreferredWidth(column, weight);
 215         if (prefSize >= 0) {
 216                 if (column->fPrefSizeConstraint == NULL) {
 217                         column->fPrefSizeConstraint = fLinearSpec->AddConstraint(1,
 218                                 column->fRight, -1, column->fLeft, kEQ, prefSize, weight,
 219                                 weight);
 220                         column->fPrefSizeConstraint->SetLabel("Pref Width");
 221                 } else {
 222                         column->fPrefSizeConstraint->SetRightSide(prefSize);
 223                         column->fPrefSizeConstraint->SetPenaltyNeg(weight);
 224                         column->fPrefSizeConstraint->SetPenaltyPos(weight);
 225                 }
 226         } else {
 227                 delete column->fPrefSizeConstraint;
 228                 column->fPrefSizeConstraint = NULL;
 229         }
 230 }
 231
 232
 233 } // end BALM namespace
 234