QGIS API Documentation  3.4.3-Madeira (2f64a3c)
qgscolorschemeregistry.cpp
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1 /***************************************************************************
2  qgscolorschemeregistry.cpp
3  -------------------
4  begin : July 2014
5  copyright : (C) 2014 by Nyall Dawson
6  email : nyall dot dawson at gmail dot com
7  ***************************************************************************/
8 
9 /***************************************************************************
10  * *
11  * This program is free software; you can redistribute it and/or modify *
12  * it under the terms of the GNU General Public License as published by *
13  * the Free Software Foundation; either version 2 of the License, or *
14  * (at your option) any later version. *
15  * *
16  ***************************************************************************/
17 
18 #include "qgscolorschemeregistry.h"
19 #include "qgscolorscheme.h"
20 #include "qgsapplication.h"
21 #include <QDir>
22 #include <QFileInfoList>
23 #include <QMutex>
24 #include <random>
25 
27 {
28  qDeleteAll( mColorSchemeList );
29  mColorSchemeList.clear();
30 }
31 
33 {
34  //get schemes from global instance
35  QList< QgsColorScheme * > schemeList = QgsApplication::colorSchemeRegistry()->schemes();
36 
37  //add to this scheme registry
38  QList< QgsColorScheme * >::iterator it = schemeList.begin();
39  for ( ; it != schemeList.end(); ++it )
40  {
41  addColorScheme( ( *it )->clone() );
42  }
43 }
44 
46 {
47  //default color schemes
52 }
53 
55 {
56  QString stylePalette = QgsApplication::pkgDataPath() + QStringLiteral( "/resources/palettes/new_layer_colors.gpl" );
57  if ( QFileInfo::exists( stylePalette ) )
58  {
59  QgsUserColorScheme *scheme = new QgsUserColorScheme( stylePalette );
60  addColorScheme( scheme );
61  setRandomStyleColorScheme( scheme );
62  }
63 }
64 
66 {
67  QString palettesDir = QgsApplication::qgisSettingsDirPath() + "palettes";
68 
69  QDir localDir;
70  if ( !localDir.mkpath( palettesDir ) )
71  {
72  return;
73  }
74 
75  QFileInfoList fileInfoList = QDir( palettesDir ).entryInfoList( QStringList( QStringLiteral( "*.gpl" ) ), QDir::Files );
76  QFileInfoList::const_iterator infoIt = fileInfoList.constBegin();
77  for ( ; infoIt != fileInfoList.constEnd(); ++infoIt )
78  {
79  addColorScheme( new QgsUserColorScheme( infoIt->fileName() ) );
80  }
81 }
82 
84 {
85  mColorSchemeList.append( scheme );
86 }
87 
88 QList<QgsColorScheme *> QgsColorSchemeRegistry::schemes() const
89 {
90  QList< QgsColorScheme * > allSchemes;
91  QList<QgsColorScheme *>::const_iterator schemeIt;
92  for ( schemeIt = mColorSchemeList.constBegin(); schemeIt != mColorSchemeList.constEnd(); ++schemeIt )
93  {
94  allSchemes.append( ( *schemeIt ) );
95  }
96  return allSchemes;
97 }
98 
99 QList<QgsColorScheme *> QgsColorSchemeRegistry::schemes( const QgsColorScheme::SchemeFlag flag ) const
100 {
101  QList< QgsColorScheme * > matchingSchemes;
102  QList<QgsColorScheme *>::const_iterator schemeIt;
103  for ( schemeIt = mColorSchemeList.constBegin(); schemeIt != mColorSchemeList.constEnd(); ++schemeIt )
104  {
105  if ( ( *schemeIt )->flags().testFlag( flag ) )
106  {
107  matchingSchemes.append( ( *schemeIt ) );
108  }
109  }
110  return matchingSchemes;
111 }
112 
114 {
115  mRandomStyleColorScheme = scheme;
116  if ( scheme )
117  {
118  mRandomStyleColors = scheme->fetchColors();
119 
120  if ( mRandomStyleColors.count() > 0 )
121  {
122  std::random_device rd;
123  std::mt19937 mt( rd() );
124  std::uniform_int_distribution<int> colorDist( 0, mRandomStyleColors.count() - 1 );
125  mNextRandomStyleColorIndex = colorDist( mt );
126  std::uniform_int_distribution<int> colorDir( 0, 1 );
127  mNextRandomStyleColorDirection = colorDir( mt ) == 0 ? -1 : 1;
128  }
129  }
130  else
131  {
132  mRandomStyleColors.clear();
133  }
134 }
135 
137 {
138  return mRandomStyleColorScheme;
139 }
140 
142 {
143  if ( mRandomStyleColors.empty() )
144  {
145  // no random color scheme available - so just use totally random colors
146 
147  // Make sure we use get uniquely seeded random numbers, and not the same sequence of numbers
148  std::random_device rd;
149  std::mt19937 mt( rd() );
150  std::uniform_int_distribution<int> hueDist( 0, 359 );
151  std::uniform_int_distribution<int> satDist( 64, 255 );
152  std::uniform_int_distribution<int> valueDist( 128, 255 );
153  return QColor::fromHsv( hueDist( mt ), satDist( mt ), valueDist( mt ) );
154  }
155  else
156  {
157  static QMutex sMutex;
158  QMutexLocker locker( &sMutex );
159  QColor res = mRandomStyleColors.at( mNextRandomStyleColorIndex ).first;
160  mNextRandomStyleColorIndex += mNextRandomStyleColorDirection;
161  if ( mNextRandomStyleColorIndex < 0 )
162  mNextRandomStyleColorIndex = mRandomStyleColors.count() - 1;
163  if ( mNextRandomStyleColorIndex >= mRandomStyleColors.count() )
164  mNextRandomStyleColorIndex = 0;
165  return res;
166  }
167 }
168 
170 {
171  if ( mRandomStyleColorScheme == scheme )
172  {
173  mRandomStyleColorScheme = nullptr;
174  mRandomStyleColors.clear();
175  }
176 
177  if ( mColorSchemeList.indexOf( scheme ) != -1 )
178  {
179  mColorSchemeList.removeAll( scheme );
180  return true;
181  }
182 
183  //not found
184  return false;
185 }
186 
187 
void populateFromInstance()
Adds all color schemes from the global instance to this color scheme.
A color scheme which contains custom colors set through QGIS app options dialog.
A color scheme which stores its colors in a gpl palette file within the "palettes" subfolder off the ...
void addDefaultSchemes()
Adds all default color schemes to this color scheme.
A color scheme which contains project specific colors set through project properties dialog...
static QString qgisSettingsDirPath()
Returns the path to the settings directory in user&#39;s home dir.
Abstract base class for color schemes.
void initStyleScheme()
Initializes the default random style color scheme for the user.
bool removeColorScheme(QgsColorScheme *scheme)
Removes all matching color schemes from the registry.
QgsColorScheme * randomStyleColorScheme()
Returns the color scheme used when fetching random colors to use for symbol styles.
QList< QgsColorScheme * > schemes() const
Returns all color schemes in the registry.
void addUserSchemes()
Creates schemes for all gpl palettes in the user&#39;s palettes folder.
void addColorScheme(QgsColorScheme *scheme)
Adds a color scheme to the registry.
static QString pkgDataPath()
Returns the common root path of all application data directories.
QColor fetchRandomStyleColor() const
Returns a random color for use with a new symbol style (e.g.
A color scheme which contains the most recently used colors.
static QgsColorSchemeRegistry * colorSchemeRegistry()
Returns the application&#39;s color scheme registry, used for managing color schemes. ...
void setRandomStyleColorScheme(QgsColorScheme *scheme)
Sets the color scheme to use when fetching random colors to use for symbol styles.
virtual QgsNamedColorList fetchColors(const QString &context=QString(), const QColor &baseColor=QColor())=0
Gets a list of colors from the scheme.
SchemeFlag
Flags for controlling behavior of color scheme.