C++/Qt/QLinearGradient

Draw in QLinearGradient

<source lang="cpp"> Foundations of Qt Development\Chapter07\brushgradients\main.cpp /*

* Copyright (c) 2006-2007, Johan Thelin
* 
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* are permitted provided that the following conditions are met:
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*       this list of conditions and the following disclaimer.
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1. include <QApplication>
2. include <QPainter>
3. include <QBrush>
4. include <QPixmap>

void createBrushShot( QBrush brush, QString name ) {

 QPixmap pixmap( 200, 200 );
 pixmap.fill( Qt::white );
 
 QPainter painter( &pixmap );
 
 painter.setBrush( brush );
 painter.drawRect( pixmap.rect() );
 
 pixmap.save( QString("%1.png").arg( name ) );

} int main( int argc, char **argv ) {

 QApplication app( argc, argv );
 
 QLinearGradient linGrad( QPointF(80, 80), QPoint( 120, 120 ) );
 linGrad.setColorAt( 0, Qt::black );
 linGrad.setColorAt( 1, Qt::white );
   
 linGrad.setSpread( QGradient::PadSpread );
 createBrushShot( QBrush( linGrad ), "LinearPad" );
 linGrad.setSpread( QGradient::RepeatSpread );
 createBrushShot( QBrush( linGrad ), "LinearRepeat" );
 linGrad.setSpread( QGradient::ReflectSpread );
 createBrushShot( QBrush( linGrad ), "LinearReflect" );  
 QRadialGradient radGrad( QPointF(100, 100), 30 );
 radGrad.setColorAt( 0, Qt::black );
 radGrad.setColorAt( 1, Qt::white );
 
 radGrad.setSpread( QGradient::PadSpread );
 createBrushShot( QBrush( radGrad ), "RadialPad" );
 radGrad.setSpread( QGradient::RepeatSpread );
 createBrushShot( QBrush( radGrad ), "RadialRepeat" );
 radGrad.setSpread( QGradient::ReflectSpread );
 createBrushShot( QBrush( radGrad ), "RadialReflect" );
 
 QConicalGradient conGrad( QPointF(100, 100), -45.0 );
 conGrad.setColorAt( 0, Qt::black );
 conGrad.setColorAt( 1, Qt::white );
 
 conGrad.setSpread( QGradient::PadSpread );
 createBrushShot( QBrush( conGrad ), "ConicalPad" );
 conGrad.setSpread( QGradient::RepeatSpread );
 createBrushShot( QBrush( conGrad ), "ConicalRepeat" );
 conGrad.setSpread( QGradient::ReflectSpread );
 createBrushShot( QBrush( conGrad ), "ConicalReflect" );
 
 QBrush textureBrush( QImage("texture.png") );
 createBrushShot( textureBrush, "TextureBrush" );
 
 return 0;

}

 </source>