QGIS API Documentation 3.27.0-Master (f261cc1f8b)
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
23QgsPaintEffect *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
75QVariantMap 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
93void 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
138void QgsColorEffect::setBrightness( int brightness )
139{
140 mBrightness = std::clamp( brightness, -255, 255 );
141}
142
143void QgsColorEffect::setContrast( int contrast )
144{
145 mContrast = std::clamp( contrast, -100, 100 );
146}
147
148void 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
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.
static QColor decodeColor(const QString &str)
static QString encodeColor(const QColor &color)