QGIS API Documentation  3.23.0-Master (c716e02dd3)
qgscoloreffect.cpp
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1 /***************************************************************************
2  qgscoloreffect.cpp
3  ------------------
4  begin : March 2015
5  copyright : (C) 2015 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 "qgscoloreffect.h"
19 #include "qgsimageoperation.h"
20 #include "qgssymbollayerutils.h"
21 #include <algorithm>
22 
23 QgsPaintEffect *QgsColorEffect::create( const QVariantMap &map )
24 {
25  QgsColorEffect *newEffect = new QgsColorEffect();
26  newEffect->readProperties( map );
27  return newEffect;
28 }
29 
31  : mColorizeColor( QColor::fromRgb( 255, 128, 128 ) )
32 {
33 
34 }
35 
37 {
38  if ( !source() || !enabled() || !context.painter() )
39  return;
40 
41  QPainter *painter = context.painter();
42 
43  //rasterize source and apply modifications
44  QImage image = sourceAsImage( context )->copy();
45 
46  QgsImageOperation::adjustBrightnessContrast( image, mBrightness, mContrast / 100.0 + 1, context.feedback() );
47 
48  if ( context.feedback() && context.feedback()->isCanceled() )
49  return;
50 
51  if ( mGrayscaleMode != QgsImageOperation::GrayscaleOff )
52  {
53  QgsImageOperation::convertToGrayscale( image, static_cast< QgsImageOperation::GrayscaleMode >( mGrayscaleMode ), context.feedback() );
54  }
55 
56  if ( context.feedback() && context.feedback()->isCanceled() )
57  return;
58 
59  QgsImageOperation::adjustHueSaturation( image, mSaturation, mColorizeOn ? mColorizeColor : QColor(), mColorizeStrength / 100.0, context.feedback() );
60 
61  if ( context.feedback() && context.feedback()->isCanceled() )
62  return;
63 
64  QgsImageOperation::multiplyOpacity( image, mOpacity, context.feedback() );
65 
66  if ( context.feedback() && context.feedback()->isCanceled() )
67  return;
68 
69  QgsScopedQPainterState painterState( painter );
70  painter->setCompositionMode( mBlendMode );
71  painter->drawImage( imageOffset( context ), image );
72 }
73 
74 
75 QVariantMap QgsColorEffect::properties() const
76 {
77  QVariantMap props;
78  props.insert( QStringLiteral( "enabled" ), mEnabled ? QStringLiteral( "1" ) : QStringLiteral( "0" ) );
79  props.insert( QStringLiteral( "draw_mode" ), QString::number( int( mDrawMode ) ) );
80  props.insert( QStringLiteral( "blend_mode" ), QString::number( int( mBlendMode ) ) );
81  props.insert( QStringLiteral( "opacity" ), QString::number( mOpacity ) );
82  props.insert( QStringLiteral( "brightness" ), QString::number( mBrightness ) );
83  props.insert( QStringLiteral( "contrast" ), QString::number( mContrast ) );
84  props.insert( QStringLiteral( "saturation" ), QString::number( mSaturation ) );
85  props.insert( QStringLiteral( "grayscale_mode" ), QString::number( int( mGrayscaleMode ) ) );
86  props.insert( QStringLiteral( "colorize" ), mColorizeOn ? QStringLiteral( "1" ) : QStringLiteral( "0" ) );
87  props.insert( QStringLiteral( "colorize_color" ), QgsSymbolLayerUtils::encodeColor( mColorizeColor ) );
88  props.insert( QStringLiteral( "colorize_strength" ), QString::number( mColorizeStrength ) );
89 
90  return props;
91 }
92 
93 void QgsColorEffect::readProperties( const QVariantMap &props )
94 {
95  bool ok;
96  QPainter::CompositionMode mode = static_cast< QPainter::CompositionMode >( props.value( QStringLiteral( "blend_mode" ) ).toInt( &ok ) );
97  if ( ok )
98  {
99  mBlendMode = mode;
100  }
101  if ( props.contains( QStringLiteral( "transparency" ) ) )
102  {
103  double transparency = props.value( QStringLiteral( "transparency" ) ).toDouble( &ok );
104  if ( ok )
105  {
106  mOpacity = 1.0 - transparency;
107  }
108  }
109  else
110  {
111  double opacity = props.value( QStringLiteral( "opacity" ) ).toDouble( &ok );
112  if ( ok )
113  {
114  mOpacity = opacity;
115  }
116  }
117  mEnabled = props.value( QStringLiteral( "enabled" ), QStringLiteral( "1" ) ).toInt();
118  mDrawMode = static_cast< QgsPaintEffect::DrawMode >( props.value( QStringLiteral( "draw_mode" ), QStringLiteral( "2" ) ).toInt() );
119 
120  mBrightness = props.value( QStringLiteral( "brightness" ), QStringLiteral( "0" ) ).toInt();
121  mContrast = props.value( QStringLiteral( "contrast" ), QStringLiteral( "0" ) ).toInt();
122  mSaturation = props.value( QStringLiteral( "saturation" ), QStringLiteral( "1.0" ) ).toDouble();
123  mGrayscaleMode = static_cast< QgsImageOperation::GrayscaleMode >( props.value( QStringLiteral( "grayscale_mode" ), QStringLiteral( "0" ) ).toInt() );
124  mColorizeOn = props.value( QStringLiteral( "colorize" ), QStringLiteral( "0" ) ).toInt();
125  if ( props.contains( QStringLiteral( "colorize_color" ) ) )
126  {
127  setColorizeColor( QgsSymbolLayerUtils::decodeColor( props.value( QStringLiteral( "colorize_color" ) ).toString() ) );
128  }
129  mColorizeStrength = props.value( QStringLiteral( "colorize_strength" ), QStringLiteral( "100" ) ).toInt();
130 }
131 
133 {
134  QgsColorEffect *newEffect = new QgsColorEffect( *this );
135  return newEffect;
136 }
137 
138 void QgsColorEffect::setBrightness( int brightness )
139 {
140  mBrightness = std::clamp( brightness, -255, 255 );
141 }
142 
143 void QgsColorEffect::setContrast( int contrast )
144 {
145  mContrast = std::clamp( contrast, -100, 100 );
146 }
147 
148 void QgsColorEffect::setColorizeColor( const QColor &colorizeColor )
149 {
150  mColorizeColor = colorizeColor;
151 }
A paint effect which alters the colors (e.g., brightness, contrast) in a source picture.
void readProperties(const QVariantMap &props) override
Reads a string map of an effect's properties and restores the effect to the state described by the pr...
double opacity() const
Returns the opacity for the effect.
QgsColorEffect * clone() const override
Duplicates an effect by creating a deep copy of the effect.
void setColorizeColor(const QColor &colorizeColor)
Sets the color used for colorizing a picture.
static QgsPaintEffect * create(const QVariantMap &map)
Creates a new QgsColorEffect effect from a properties string map.
int contrast() const
Returns the contrast modification for the effect.
int brightness() const
Returns the brightness modification for the effect.
void setContrast(int contrast)
Sets the contrast modification for the effect.
void draw(QgsRenderContext &context) override
Handles drawing of the effect's result on to the specified render context.
void setBrightness(int brightness)
Sets the brightness modification for the effect.
QVariantMap properties() const override
Returns the properties describing the paint effect encoded in a string format.
QColor colorizeColor() const
Returns the color used for colorizing a picture.
bool isCanceled() const SIP_HOLDGIL
Tells whether the operation has been canceled already.
Definition: qgsfeedback.h:54
static void adjustHueSaturation(QImage &image, double saturation, const QColor &colorizeColor=QColor(), double colorizeStrength=1.0, QgsFeedback *feedback=nullptr)
Alter the hue or saturation of a QImage.
static void multiplyOpacity(QImage &image, double factor, QgsFeedback *feedback=nullptr)
Multiplies opacity of image pixel values by a factor.
static void adjustBrightnessContrast(QImage &image, int brightness, double contrast, QgsFeedback *feedback=nullptr)
Alter the brightness or contrast of a QImage.
static void convertToGrayscale(QImage &image, GrayscaleMode mode=GrayscaleLuminosity, QgsFeedback *feedback=nullptr)
Convert a QImage to a grayscale image.
GrayscaleMode
Modes for converting a QImage to grayscale.
@ GrayscaleOff
No change.
Base class for visual effects which can be applied to QPicture drawings.
DrawMode mDrawMode
const QPicture * source() const
Returns the source QPicture.
QPointF imageOffset(const QgsRenderContext &context) const
Returns the offset which should be used when drawing the source image on to a destination render cont...
bool enabled() const
Returns whether the effect is enabled.
DrawMode
Drawing modes for effects.
QImage * sourceAsImage(QgsRenderContext &context)
Returns the source QPicture rendered to a new QImage.
Contains information about the context of a rendering operation.
QPainter * painter()
Returns the destination QPainter for the render operation.
QgsFeedback * feedback() const
Returns the feedback object that can be queried regularly during rendering to check if rendering shou...
Scoped object for saving and restoring a QPainter object's state.
static QColor decodeColor(const QString &str)
static QString encodeColor(const QColor &color)