本文整理汇总了C++中QgsSimplifyMethod::setTolerance方法的典型用法代码示例。如果您正苦于以下问题：C++ QgsSimplifyMethod::setTolerance方法的具体用法？C++ QgsSimplifyMethod::setTolerance怎么用？C++ QgsSimplifyMethod::setTolerance使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类QgsSimplifyMethod的用法示例。
在下文中一共展示了QgsSimplifyMethod::setTolerance方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: render
//.........这里部分代码省略.........
{
double map2pixelTol = mSimplifyMethod.threshold();
bool validTransform = true;
const QgsMapToPixel& mtp = mContext.mapToPixel();
map2pixelTol *= mtp.mapUnitsPerPixel();
const QgsCoordinateTransform* ct = mContext.coordinateTransform();
// resize the tolerance using the change of size of an 1-BBOX from the source CoordinateSystem to the target CoordinateSystem
if ( ct && !( ct->isShortCircuited() ) )
{
try
{
QgsPoint center = mContext.extent().center();
double rectSize = ct->sourceCrs().geographicFlag() ? 0.0008983 /* ~100/(40075014/360=111319.4833) */ : 100;
QgsRectangle sourceRect = QgsRectangle( center.x(), center.y(), center.x() + rectSize, center.y() + rectSize );
QgsRectangle targetRect = ct->transform( sourceRect );
QgsDebugMsg( QString( "Simplify - SourceTransformRect=%1" ).arg( sourceRect.toString( 16 ) ) );
QgsDebugMsg( QString( "Simplify - TargetTransformRect=%1" ).arg( targetRect.toString( 16 ) ) );
if ( !sourceRect.isEmpty() && sourceRect.isFinite() && !targetRect.isEmpty() && targetRect.isFinite() )
{
QgsPoint minimumSrcPoint( sourceRect.xMinimum(), sourceRect.yMinimum() );
QgsPoint maximumSrcPoint( sourceRect.xMaximum(), sourceRect.yMaximum() );
QgsPoint minimumDstPoint( targetRect.xMinimum(), targetRect.yMinimum() );
QgsPoint maximumDstPoint( targetRect.xMaximum(), targetRect.yMaximum() );
double sourceHypothenuse = sqrt( minimumSrcPoint.sqrDist( maximumSrcPoint ) );
double targetHypothenuse = sqrt( minimumDstPoint.sqrDist( maximumDstPoint ) );
QgsDebugMsg( QString( "Simplify - SourceHypothenuse=%1" ).arg( sourceHypothenuse ) );
QgsDebugMsg( QString( "Simplify - TargetHypothenuse=%1" ).arg( targetHypothenuse ) );
if ( !qgsDoubleNear( targetHypothenuse, 0.0 ) )
map2pixelTol *= ( sourceHypothenuse / targetHypothenuse );
}
}
catch ( QgsCsException &cse )
{
QgsMessageLog::logMessage( QObject::tr( "Simplify transform error caught: %1" ).arg( cse.what() ), QObject::tr( "CRS" ) );
validTransform = false;
}
}
if ( validTransform )
{
QgsSimplifyMethod simplifyMethod;
simplifyMethod.setMethodType( QgsSimplifyMethod::OptimizeForRendering );
simplifyMethod.setTolerance( map2pixelTol );
simplifyMethod.setThreshold( mSimplifyMethod.threshold() );
simplifyMethod.setForceLocalOptimization( mSimplifyMethod.forceLocalOptimization() );
featureRequest.setSimplifyMethod( simplifyMethod );
QgsVectorSimplifyMethod vectorMethod = mSimplifyMethod;
mContext.setVectorSimplifyMethod( vectorMethod );
}
else
{
QgsVectorSimplifyMethod vectorMethod;
vectorMethod.setSimplifyHints( QgsVectorSimplifyMethod::NoSimplification );
mContext.setVectorSimplifyMethod( vectorMethod );
}
}
else
{
QgsVectorSimplifyMethod vectorMethod;
vectorMethod.setSimplifyHints( QgsVectorSimplifyMethod::NoSimplification );
mContext.setVectorSimplifyMethod( vectorMethod );
}
QgsFeatureIterator fit = mSource->getFeatures( featureRequest );
if (( mRendererV2->capabilities() & QgsFeatureRendererV2::SymbolLevels ) && mRendererV2->usingSymbolLevels() )
drawRendererV2Levels( fit );
else
drawRendererV2( fit );
if ( usingEffect )
{
mRendererV2->paintEffect()->end( mContext );
}
//apply layer transparency for vector layers
if ( mContext.useAdvancedEffects() && mLayerTransparency != 0 )
{
// a layer transparency has been set, so update the alpha for the flattened layer
// by combining it with the layer transparency
QColor transparentFillColor = QColor( 0, 0, 0, 255 - ( 255 * mLayerTransparency / 100 ) );
// use destination in composition mode to merge source's alpha with destination
mContext.painter()->setCompositionMode( QPainter::CompositionMode_DestinationIn );
mContext.painter()->fillRect( 0, 0, mContext.painter()->device()->width(),
mContext.painter()->device()->height(), transparentFillColor );
}
return true;
}示例2: render
//.........这里部分代码省略.........
// enable the simplification of the geometries (Using the current map2pixel context) before send it to renderer engine.
if ( mSimplifyGeometry )
{
double map2pixelTol = mSimplifyMethod.threshold();
bool validTransform = true;
const QgsMapToPixel &mtp = mContext.mapToPixel();
map2pixelTol *= mtp.mapUnitsPerPixel();
QgsCoordinateTransform ct = mContext.coordinateTransform();
// resize the tolerance using the change of size of an 1-BBOX from the source CoordinateSystem to the target CoordinateSystem
if ( ct.isValid() && !ct.isShortCircuited() )
{
try
{
QgsPointXY center = mContext.extent().center();
double rectSize = ct.sourceCrs().isGeographic() ? 0.0008983 /* ~100/(40075014/360=111319.4833) */ : 100;
QgsRectangle sourceRect = QgsRectangle( center.x(), center.y(), center.x() + rectSize, center.y() + rectSize );
QgsRectangle targetRect = ct.transform( sourceRect );
QgsDebugMsgLevel( QStringLiteral( "Simplify - SourceTransformRect=%1" ).arg( sourceRect.toString( 16 ) ), 4 );
QgsDebugMsgLevel( QStringLiteral( "Simplify - TargetTransformRect=%1" ).arg( targetRect.toString( 16 ) ), 4 );
if ( !sourceRect.isEmpty() && sourceRect.isFinite() && !targetRect.isEmpty() && targetRect.isFinite() )
{
QgsPointXY minimumSrcPoint( sourceRect.xMinimum(), sourceRect.yMinimum() );
QgsPointXY maximumSrcPoint( sourceRect.xMaximum(), sourceRect.yMaximum() );
QgsPointXY minimumDstPoint( targetRect.xMinimum(), targetRect.yMinimum() );
QgsPointXY maximumDstPoint( targetRect.xMaximum(), targetRect.yMaximum() );
double sourceHypothenuse = std::sqrt( minimumSrcPoint.sqrDist( maximumSrcPoint ) );
double targetHypothenuse = std::sqrt( minimumDstPoint.sqrDist( maximumDstPoint ) );
QgsDebugMsgLevel( QStringLiteral( "Simplify - SourceHypothenuse=%1" ).arg( sourceHypothenuse ), 4 );
QgsDebugMsgLevel( QStringLiteral( "Simplify - TargetHypothenuse=%1" ).arg( targetHypothenuse ), 4 );
if ( !qgsDoubleNear( targetHypothenuse, 0.0 ) )
map2pixelTol *= ( sourceHypothenuse / targetHypothenuse );
}
}
catch ( QgsCsException &cse )
{
QgsMessageLog::logMessage( QObject::tr( "Simplify transform error caught: %1" ).arg( cse.what() ), QObject::tr( "CRS" ) );
validTransform = false;
}
}
if ( validTransform )
{
QgsSimplifyMethod simplifyMethod;
simplifyMethod.setMethodType( QgsSimplifyMethod::OptimizeForRendering );
simplifyMethod.setTolerance( map2pixelTol );
simplifyMethod.setThreshold( mSimplifyMethod.threshold() );
simplifyMethod.setForceLocalOptimization( mSimplifyMethod.forceLocalOptimization() );
featureRequest.setSimplifyMethod( simplifyMethod );
QgsVectorSimplifyMethod vectorMethod = mSimplifyMethod;
vectorMethod.setTolerance( map2pixelTol );
mContext.setVectorSimplifyMethod( vectorMethod );
}
else
{
QgsVectorSimplifyMethod vectorMethod;
vectorMethod.setSimplifyHints( QgsVectorSimplifyMethod::NoSimplification );
mContext.setVectorSimplifyMethod( vectorMethod );
}
}
else
{
QgsVectorSimplifyMethod vectorMethod;
vectorMethod.setSimplifyHints( QgsVectorSimplifyMethod::NoSimplification );
mContext.setVectorSimplifyMethod( vectorMethod );
}
QgsFeatureIterator fit = mSource->getFeatures( featureRequest );
// Attach an interruption checker so that iterators that have potentially
// slow fetchFeature() implementations, such as in the WFS provider, can
// check it, instead of relying on just the mContext.renderingStopped() check
// in drawRenderer()
fit.setInterruptionChecker( mInterruptionChecker.get() );
if ( ( mRenderer->capabilities() & QgsFeatureRenderer::SymbolLevels ) && mRenderer->usingSymbolLevels() )
drawRendererLevels( fit );
else
drawRenderer( fit );
if ( !fit.isValid() )
{
mErrors.append( QStringLiteral( "Data source invalid" ) );
}
if ( usingEffect )
{
mRenderer->paintEffect()->end( mContext );
}
return true;
}