QGIS API Documentation 3.37.0-Master (fdefdf9c27f)
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 "qgscolorutils.h"
20#include "qgsimageoperation.h"
21#include "qgsrendercontext.h"
22
23#include <algorithm>
24
25QgsPaintEffect *QgsColorEffect::create( const QVariantMap &map )
26{
27 QgsColorEffect *newEffect = new QgsColorEffect();
28 newEffect->readProperties( map );
29 return newEffect;
30}
31
33 : mColorizeColor( QColor::fromRgb( 255, 128, 128 ) )
34{
35
36}
37
39{
40 if ( !source() || !enabled() || !context.painter() )
41 return;
42
43 QPainter *painter = context.painter();
44
45 //rasterize source and apply modifications
46 QImage image = sourceAsImage( context )->copy();
47
48 QgsImageOperation::adjustBrightnessContrast( image, mBrightness, mContrast / 100.0 + 1, context.feedback() );
49
50 if ( context.feedback() && context.feedback()->isCanceled() )
51 return;
52
53 if ( mGrayscaleMode != QgsImageOperation::GrayscaleOff )
54 {
55 QgsImageOperation::convertToGrayscale( image, static_cast< QgsImageOperation::GrayscaleMode >( mGrayscaleMode ), context.feedback() );
56 }
57
58 if ( context.feedback() && context.feedback()->isCanceled() )
59 return;
60
61 QgsImageOperation::adjustHueSaturation( image, mSaturation, mColorizeOn ? mColorizeColor : QColor(), mColorizeStrength / 100.0, context.feedback() );
62
63 if ( context.feedback() && context.feedback()->isCanceled() )
64 return;
65
66 QgsImageOperation::multiplyOpacity( image, mOpacity, context.feedback() );
67
68 if ( context.feedback() && context.feedback()->isCanceled() )
69 return;
70
71 QgsScopedQPainterState painterState( painter );
72 painter->setCompositionMode( mBlendMode );
73 painter->drawImage( imageOffset( context ), image );
74}
75
76
77QVariantMap QgsColorEffect::properties() const
78{
79 QVariantMap props;
80 props.insert( QStringLiteral( "enabled" ), mEnabled ? QStringLiteral( "1" ) : QStringLiteral( "0" ) );
81 props.insert( QStringLiteral( "draw_mode" ), QString::number( int( mDrawMode ) ) );
82 props.insert( QStringLiteral( "blend_mode" ), QString::number( int( mBlendMode ) ) );
83 props.insert( QStringLiteral( "opacity" ), QString::number( mOpacity ) );
84 props.insert( QStringLiteral( "brightness" ), QString::number( mBrightness ) );
85 props.insert( QStringLiteral( "contrast" ), QString::number( mContrast ) );
86 props.insert( QStringLiteral( "saturation" ), QString::number( mSaturation ) );
87 props.insert( QStringLiteral( "grayscale_mode" ), QString::number( int( mGrayscaleMode ) ) );
88 props.insert( QStringLiteral( "colorize" ), mColorizeOn ? QStringLiteral( "1" ) : QStringLiteral( "0" ) );
89 props.insert( QStringLiteral( "colorize_color" ), QgsColorUtils::colorToString( mColorizeColor ) );
90 props.insert( QStringLiteral( "colorize_strength" ), QString::number( mColorizeStrength ) );
91
92 return props;
93}
94
95void QgsColorEffect::readProperties( const QVariantMap &props )
96{
97 bool ok;
98 QPainter::CompositionMode mode = static_cast< QPainter::CompositionMode >( props.value( QStringLiteral( "blend_mode" ) ).toInt( &ok ) );
99 if ( ok )
100 {
101 mBlendMode = mode;
102 }
103 if ( props.contains( QStringLiteral( "transparency" ) ) )
104 {
105 double transparency = props.value( QStringLiteral( "transparency" ) ).toDouble( &ok );
106 if ( ok )
107 {
108 mOpacity = 1.0 - transparency;
109 }
110 }
111 else
112 {
113 double opacity = props.value( QStringLiteral( "opacity" ) ).toDouble( &ok );
114 if ( ok )
115 {
116 mOpacity = opacity;
117 }
118 }
119 mEnabled = props.value( QStringLiteral( "enabled" ), QStringLiteral( "1" ) ).toInt();
120 mDrawMode = static_cast< QgsPaintEffect::DrawMode >( props.value( QStringLiteral( "draw_mode" ), QStringLiteral( "2" ) ).toInt() );
121
122 mBrightness = props.value( QStringLiteral( "brightness" ), QStringLiteral( "0" ) ).toInt();
123 mContrast = props.value( QStringLiteral( "contrast" ), QStringLiteral( "0" ) ).toInt();
124 mSaturation = props.value( QStringLiteral( "saturation" ), QStringLiteral( "1.0" ) ).toDouble();
125 mGrayscaleMode = static_cast< QgsImageOperation::GrayscaleMode >( props.value( QStringLiteral( "grayscale_mode" ), QStringLiteral( "0" ) ).toInt() );
126 mColorizeOn = props.value( QStringLiteral( "colorize" ), QStringLiteral( "0" ) ).toInt();
127 if ( props.contains( QStringLiteral( "colorize_color" ) ) )
128 {
129 setColorizeColor( QgsColorUtils::colorFromString( props.value( QStringLiteral( "colorize_color" ) ).toString() ) );
130 }
131 mColorizeStrength = props.value( QStringLiteral( "colorize_strength" ), QStringLiteral( "100" ) ).toInt();
132}
133
135{
136 QgsColorEffect *newEffect = new QgsColorEffect( *this );
137 return newEffect;
138}
139
140void QgsColorEffect::setBrightness( int brightness )
141{
142 mBrightness = std::clamp( brightness, -255, 255 );
143}
144
145void QgsColorEffect::setContrast( int contrast )
146{
147 mContrast = std::clamp( contrast, -100, 100 );
148}
149
150void QgsColorEffect::setColorizeColor( const QColor &colorizeColor )
151{
152 mColorizeColor = colorizeColor;
153}
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.
static QColor colorFromString(const QString &string)
Decodes a string into a color value.
static QString colorToString(const QColor &color)
Encodes a color into a string value.
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition: qgsfeedback.h:53
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
QPointF imageOffset(const QgsRenderContext &context) const
Returns the offset which should be used when drawing the source image on to a destination render cont...
const QPicture * source() const
Returns the source QPicture.
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.