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qgsrasterlayerrenderer.cpp
609 lines (518 loc) · 26.3 KB
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qgsrasterlayerrenderer.cpp
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/***************************************************************************
qgsrasterlayerrenderer.cpp
--------------------------------------
Date : December 2013
Copyright : (C) 2013 by Martin Dobias
Email : wonder dot sk at gmail dot com
***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************/
#include "qgsrasterlayerrenderer.h"
#include "qgsmessagelog.h"
#include "qgsrasterdataprovider.h"
#include "qgsrasterdrawer.h"
#include "qgsrasteriterator.h"
#include "qgsrasterlayer.h"
#include "qgsrasterprojector.h"
#include "qgsrendercontext.h"
#include "qgsrasterrenderer.h"
#include "qgsexception.h"
#include "qgsrasterlayertemporalproperties.h"
#include "qgsmapclippingutils.h"
#include "qgsrasterpipe.h"
#include "qgselevationmap.h"
#include "qgsgdalutils.h"
#include "qgsrasterresamplefilter.h"
#include "qgsrasterlayerelevationproperties.h"
#include <QElapsedTimer>
#include <QPointer>
#include <QThread>
///@cond PRIVATE
QgsRasterLayerRendererFeedback::QgsRasterLayerRendererFeedback( QgsRasterLayerRenderer *r )
: mR( r )
, mMinimalPreviewInterval( 250 )
{
setRenderPartialOutput( r->renderContext()->testFlag( Qgis::RenderContextFlag::RenderPartialOutput ) );
}
void QgsRasterLayerRendererFeedback::onNewData()
{
if ( !renderPartialOutput() )
return; // we were not asked for partial renders and we may not have a temporary image for overwriting...
// update only once upon a time
// (preview itself takes some time)
if ( mLastPreview.isValid() && mLastPreview.msecsTo( QTime::currentTime() ) < mMinimalPreviewInterval )
return;
// TODO: update only the area that got new data
QgsDebugMsgLevel( QStringLiteral( "new raster preview! %1" ).arg( mLastPreview.msecsTo( QTime::currentTime() ) ), 3 );
QElapsedTimer t;
t.start();
QgsRasterBlockFeedback feedback;
feedback.setPreviewOnly( true );
feedback.setRenderPartialOutput( true );
QgsRasterIterator iterator( mR->mPipe->last() );
QgsRasterDrawer drawer( &iterator );
drawer.draw( *( mR->renderContext() ), mR->mRasterViewPort, &feedback );
mR->mReadyToCompose = true;
QgsDebugMsgLevel( QStringLiteral( "total raster preview time: %1 ms" ).arg( t.elapsed() ), 3 );
mLastPreview = QTime::currentTime();
}
///@endcond
///
QgsRasterLayerRenderer::QgsRasterLayerRenderer( QgsRasterLayer *layer, QgsRenderContext &rendererContext )
: QgsMapLayerRenderer( layer->id(), &rendererContext )
, mLayerOpacity( layer->opacity() )
, mProviderCapabilities( static_cast<QgsRasterDataProvider::Capability>( layer->dataProvider()->capabilities() ) )
, mFeedback( new QgsRasterLayerRendererFeedback( this ) )
{
mReadyToCompose = false;
QgsMapToPixel mapToPixel = rendererContext.mapToPixel();
if ( rendererContext.mapToPixel().mapRotation() )
{
// unset rotation for the sake of local computations.
// Rotation will be handled by QPainter later
// TODO: provide a method of QgsMapToPixel to fetch map center
// in geographical units
const QgsPointXY center = mapToPixel.toMapCoordinates(
static_cast<int>( mapToPixel.mapWidth() / 2.0 ),
static_cast<int>( mapToPixel.mapHeight() / 2.0 )
);
mapToPixel.setMapRotation( 0, center.x(), center.y() );
}
QgsRectangle myProjectedViewExtent;
QgsRectangle myProjectedLayerExtent;
if ( rendererContext.coordinateTransform().isValid() )
{
QgsDebugMsgLevel( QStringLiteral( "coordinateTransform set -> project extents." ), 4 );
if ( rendererContext.extent().xMinimum() == std::numeric_limits<double>::lowest() &&
rendererContext.extent().yMinimum() == std::numeric_limits<double>::lowest() &&
rendererContext.extent().xMaximum() == std::numeric_limits<double>::max() &&
rendererContext.extent().yMaximum() == std::numeric_limits<double>::max() )
{
// We get in this situation if the view CRS is geographical and the
// extent goes beyond -180,-90,180,90. To avoid reprojection issues to the
// layer CRS, then this dummy extent is returned by QgsMapRendererJob::reprojectToLayerExtent()
// Don't try to reproject it now to view extent as this would return
// a null rectangle.
myProjectedViewExtent = rendererContext.extent();
}
else
{
try
{
QgsCoordinateTransform ct = rendererContext.coordinateTransform();
ct.setBallparkTransformsAreAppropriate( true );
myProjectedViewExtent = ct.transformBoundingBox( rendererContext.extent() );
}
catch ( QgsCsException &cs )
{
QgsMessageLog::logMessage( QObject::tr( "Could not reproject view extent: %1" ).arg( cs.what() ), QObject::tr( "Raster" ) );
myProjectedViewExtent.setMinimal();
}
}
try
{
QgsCoordinateTransform ct = rendererContext.coordinateTransform();
ct.setBallparkTransformsAreAppropriate( true );
myProjectedLayerExtent = ct.transformBoundingBox( layer->extent() );
}
catch ( QgsCsException &cs )
{
QgsMessageLog::logMessage( QObject::tr( "Could not reproject layer extent: %1" ).arg( cs.what() ), QObject::tr( "Raster" ) );
myProjectedLayerExtent.setMinimal();
}
}
else
{
QgsDebugMsgLevel( QStringLiteral( "coordinateTransform not set" ), 4 );
myProjectedViewExtent = rendererContext.extent();
myProjectedLayerExtent = layer->extent();
}
// clip raster extent to view extent
QgsRectangle myRasterExtent = layer->ignoreExtents() ? myProjectedViewExtent : myProjectedViewExtent.intersect( myProjectedLayerExtent );
if ( myRasterExtent.isEmpty() )
{
QgsDebugMsgLevel( QStringLiteral( "draw request outside view extent." ), 2 );
// nothing to do
return;
}
QgsDebugMsgLevel( "theViewExtent is " + rendererContext.extent().toString(), 4 );
QgsDebugMsgLevel( "myProjectedViewExtent is " + myProjectedViewExtent.toString(), 4 );
QgsDebugMsgLevel( "myProjectedLayerExtent is " + myProjectedLayerExtent.toString(), 4 );
QgsDebugMsgLevel( "myRasterExtent is " + myRasterExtent.toString(), 4 );
//
// The first thing we do is set up the QgsRasterViewPort. This struct stores all the settings
// relating to the size (in pixels and coordinate system units) of the raster part that is
// in view in the map window. It also stores the origin.
//
//this is not a class level member because every time the user pans or zooms
//the contents of the rasterViewPort will change
mRasterViewPort = new QgsRasterViewPort();
mRasterViewPort->mDrawnExtent = myRasterExtent;
if ( rendererContext.coordinateTransform().isValid() )
{
mRasterViewPort->mSrcCRS = layer->crs();
mRasterViewPort->mDestCRS = rendererContext.coordinateTransform().destinationCrs();
mRasterViewPort->mTransformContext = rendererContext.transformContext();
}
else
{
mRasterViewPort->mSrcCRS = QgsCoordinateReferenceSystem(); // will be invalid
mRasterViewPort->mDestCRS = QgsCoordinateReferenceSystem(); // will be invalid
}
// get dimensions of clipped raster image in device coordinate space (this is the size of the viewport)
mRasterViewPort->mTopLeftPoint = mapToPixel.transform( myRasterExtent.xMinimum(), myRasterExtent.yMaximum() );
mRasterViewPort->mBottomRightPoint = mapToPixel.transform( myRasterExtent.xMaximum(), myRasterExtent.yMinimum() );
// align to output device grid, i.e. std::floor/ceil to integers
// TODO: this should only be done if paint device is raster - screen, image
// for other devices (pdf) it can have floating point origin
// we could use floating point for raster devices as well, but respecting the
// output device grid should make it more effective as the resampling is done in
// the provider anyway
mRasterViewPort->mTopLeftPoint.setX( std::floor( mRasterViewPort->mTopLeftPoint.x() ) );
mRasterViewPort->mTopLeftPoint.setY( std::floor( mRasterViewPort->mTopLeftPoint.y() ) );
mRasterViewPort->mBottomRightPoint.setX( std::ceil( mRasterViewPort->mBottomRightPoint.x() ) );
mRasterViewPort->mBottomRightPoint.setY( std::ceil( mRasterViewPort->mBottomRightPoint.y() ) );
// recalc myRasterExtent to aligned values
myRasterExtent.set(
mapToPixel.toMapCoordinates( mRasterViewPort->mTopLeftPoint.x(),
mRasterViewPort->mBottomRightPoint.y() ),
mapToPixel.toMapCoordinates( mRasterViewPort->mBottomRightPoint.x(),
mRasterViewPort->mTopLeftPoint.y() )
);
//raster viewport top left / bottom right are already rounded to int
mRasterViewPort->mWidth = static_cast<qgssize>( std::abs( mRasterViewPort->mBottomRightPoint.x() - mRasterViewPort->mTopLeftPoint.x() ) );
mRasterViewPort->mHeight = static_cast<qgssize>( std::abs( mRasterViewPort->mBottomRightPoint.y() - mRasterViewPort->mTopLeftPoint.y() ) );
const double dpi = 25.4 * rendererContext.scaleFactor();
if ( mProviderCapabilities & QgsRasterDataProvider::DpiDependentData
&& rendererContext.dpiTarget() >= 0.0 )
{
const double dpiScaleFactor = rendererContext.dpiTarget() / dpi;
mRasterViewPort->mWidth *= dpiScaleFactor;
mRasterViewPort->mHeight *= dpiScaleFactor;
}
else
{
rendererContext.setDpiTarget( -1.0 );
}
//the drawable area can start to get very very large when you get down displaying 2x2 or smaller, this is because
//mapToPixel.mapUnitsPerPixel() is less then 1,
//so we will just get the pixel data and then render these special cases differently in paintImageToCanvas()
QgsDebugMsgLevel( QStringLiteral( "mapUnitsPerPixel = %1" ).arg( mapToPixel.mapUnitsPerPixel() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "mWidth = %1" ).arg( layer->width() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "mHeight = %1" ).arg( layer->height() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "myRasterExtent.xMinimum() = %1" ).arg( myRasterExtent.xMinimum() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "myRasterExtent.xMaximum() = %1" ).arg( myRasterExtent.xMaximum() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "myRasterExtent.yMinimum() = %1" ).arg( myRasterExtent.yMinimum() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "myRasterExtent.yMaximum() = %1" ).arg( myRasterExtent.yMaximum() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "mTopLeftPoint.x() = %1" ).arg( mRasterViewPort->mTopLeftPoint.x() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "mBottomRightPoint.x() = %1" ).arg( mRasterViewPort->mBottomRightPoint.x() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "mTopLeftPoint.y() = %1" ).arg( mRasterViewPort->mTopLeftPoint.y() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "mBottomRightPoint.y() = %1" ).arg( mRasterViewPort->mBottomRightPoint.y() ), 3 );
QgsDebugMsgLevel( QStringLiteral( "mWidth = %1" ).arg( mRasterViewPort->mWidth ), 3 );
QgsDebugMsgLevel( QStringLiteral( "mHeight = %1" ).arg( mRasterViewPort->mHeight ), 3 );
// /\/\/\ - added to handle zoomed-in rasters
// TODO R->mLastViewPort = *mRasterViewPort;
// TODO: is it necessary? Probably WMS only?
layer->dataProvider()->setDpi( dpi );
// copy the whole raster pipe!
mPipe.reset( new QgsRasterPipe( *layer->pipe() ) );
QObject::connect( mPipe->provider(), &QgsRasterDataProvider::statusChanged, layer, &QgsRasterLayer::statusChanged );
QgsRasterRenderer *rasterRenderer = mPipe->renderer();
if ( rasterRenderer
&& !( rendererContext.flags() & Qgis::RenderContextFlag::RenderPreviewJob )
&& !( rendererContext.flags() & Qgis::RenderContextFlag::Render3DMap ) )
{
layer->refreshRendererIfNeeded( rasterRenderer, rendererContext.extent() );
}
mPipe->evaluateDataDefinedProperties( rendererContext.expressionContext() );
const QgsRasterLayerTemporalProperties *temporalProperties = qobject_cast< const QgsRasterLayerTemporalProperties * >( layer->temporalProperties() );
if ( temporalProperties->isActive() && renderContext()->isTemporal() )
{
switch ( temporalProperties->mode() )
{
case Qgis::RasterTemporalMode::FixedTemporalRange:
case Qgis::RasterTemporalMode::RedrawLayerOnly:
break;
case Qgis::RasterTemporalMode::TemporalRangeFromDataProvider:
// in this mode we need to pass on the desired render temporal range to the data provider
if ( mPipe->provider()->temporalCapabilities() )
{
mPipe->provider()->temporalCapabilities()->setRequestedTemporalRange( rendererContext.temporalRange() );
mPipe->provider()->temporalCapabilities()->setIntervalHandlingMethod( temporalProperties->intervalHandlingMethod() );
}
break;
}
}
else if ( mPipe->provider()->temporalCapabilities() )
{
mPipe->provider()->temporalCapabilities()->setRequestedTemporalRange( QgsDateTimeRange() );
mPipe->provider()->temporalCapabilities()->setIntervalHandlingMethod( temporalProperties->intervalHandlingMethod() );
}
mClippingRegions = QgsMapClippingUtils::collectClippingRegionsForLayer( *renderContext(), layer );
if ( layer->elevationProperties() && layer->elevationProperties()->hasElevation() )
{
QgsRasterLayerElevationProperties *elevProp
= static_cast<QgsRasterLayerElevationProperties *>( layer->elevationProperties() );
mDrawElevationMap = true;
mElevationScale = elevProp->zScale();
mElevationOffset = elevProp->zOffset();
mElevationBand = elevProp->bandNumber();
}
mFeedback->setRenderContext( rendererContext );
mPipe->moveToThread( nullptr );
}
QgsRasterLayerRenderer::~QgsRasterLayerRenderer()
{
delete mFeedback;
delete mRasterViewPort;
}
bool QgsRasterLayerRenderer::render()
{
// Skip rendering of out of view tiles (xyz)
if ( !mRasterViewPort || ( renderContext()->testFlag( Qgis::RenderContextFlag::RenderPreviewJob ) &&
!( mProviderCapabilities &
QgsRasterInterface::Capability::Prefetch ) ) )
return true;
mPipe->moveToThread( QThread::currentThread() );
QElapsedTimer time;
time.start();
//
//
// The goal here is to make as many decisions as possible early on (outside of the rendering loop)
// so that we can maximise performance of the rendering process. So now we check which drawing
// procedure to use :
//
const QgsScopedQPainterState painterSate( renderContext()->painter() );
if ( !mClippingRegions.empty() )
{
bool needsPainterClipPath = false;
const QPainterPath path = QgsMapClippingUtils::calculatePainterClipRegion( mClippingRegions, *renderContext(), Qgis::LayerType::Raster, needsPainterClipPath );
if ( needsPainterClipPath )
renderContext()->painter()->setClipPath( path, Qt::IntersectClip );
}
QgsRasterProjector *projector = mPipe->projector();
bool restoreOldResamplingStage = false;
const Qgis::RasterResamplingStage oldResamplingState = mPipe->resamplingStage();
// TODO add a method to interface to get provider and get provider
// params in QgsRasterProjector
if ( projector )
{
// Force provider resampling if reprojection is needed
if ( ( mPipe->provider()->providerCapabilities() & QgsRasterDataProvider::ProviderHintCanPerformProviderResampling ) &&
mRasterViewPort->mSrcCRS != mRasterViewPort->mDestCRS &&
oldResamplingState != Qgis::RasterResamplingStage::Provider )
{
restoreOldResamplingStage = true;
mPipe->setResamplingStage( Qgis::RasterResamplingStage::Provider );
}
projector->setCrs( mRasterViewPort->mSrcCRS, mRasterViewPort->mDestCRS, mRasterViewPort->mTransformContext );
}
// important -- disable SmoothPixmapTransform for raster layer renders. We want individual pixels to be clearly defined!
renderContext()->painter()->setRenderHint( QPainter::SmoothPixmapTransform, false );
// Drawer to pipe?
QgsRasterIterator iterator( mPipe->last() );
QgsRasterDrawer drawer( &iterator );
drawer.draw( *( renderContext() ), mRasterViewPort, mFeedback );
if ( mDrawElevationMap )
drawElevationMap();
if ( restoreOldResamplingStage )
{
mPipe->setResamplingStage( oldResamplingState );
}
const QStringList errors = mFeedback->errors();
for ( const QString &error : errors )
{
mErrors.append( error );
}
QgsDebugMsgLevel( QStringLiteral( "total raster draw time (ms): %1" ).arg( time.elapsed(), 5 ), 4 );
mReadyToCompose = true;
mPipe->moveToThread( nullptr );
return !mFeedback->isCanceled();
}
QgsFeedback *QgsRasterLayerRenderer::feedback() const
{
return mFeedback;
}
bool QgsRasterLayerRenderer::forceRasterRender() const
{
if ( !mRasterViewPort || !mPipe )
return false; // this layer is not going to get rendered
// preview of intermediate raster rendering results requires a temporary output image
if ( renderContext()->testFlag( Qgis::RenderContextFlag::RenderPartialOutput ) )
return true;
if ( QgsRasterRenderer *renderer = mPipe->renderer() )
{
if ( !( renderer->flags() & Qgis::RasterRendererFlag::InternalLayerOpacityHandling )
&& renderContext()->testFlag( Qgis::RenderContextFlag::UseAdvancedEffects ) && ( !qgsDoubleNear( mLayerOpacity, 1.0 ) ) )
return true;
}
return false;
}
void QgsRasterLayerRenderer::drawElevationMap()
{
QgsRasterDataProvider *dataProvider = mPipe->provider();
if ( renderContext()->elevationMap() && dataProvider )
{
double dpiScalefactor;
if ( renderContext()->dpiTarget() >= 0.0 )
dpiScalefactor = renderContext()->dpiTarget() / ( renderContext()->scaleFactor() * 25.4 );
else
dpiScalefactor = 1.0;
int outputWidth = static_cast<int>( static_cast<double>( mRasterViewPort->mWidth ) / dpiScalefactor ) ;
int outputHeight = static_cast<int>( static_cast<double>( mRasterViewPort->mHeight ) / dpiScalefactor );
QSize viewSize = renderContext()->deviceOutputSize();
int viewWidth = static_cast<int>( viewSize.width() / dpiScalefactor );
int viewHeight = static_cast<int>( viewSize.height() / dpiScalefactor );
bool canRenderElevation = false;
std::unique_ptr<QgsRasterBlock> elevationBlock;
if ( mRasterViewPort->mSrcCRS == mRasterViewPort->mDestCRS )
{
elevationBlock.reset(
dataProvider->block(
mElevationBand,
mRasterViewPort->mDrawnExtent,
outputWidth,
outputHeight,
mFeedback ) );
canRenderElevation = true;
}
else
{
// Destinaton CRS is different from the source CRS.
// Using the raster projector lead to have big artifacts when rendering the elevation map.
// To get a smoother elevation map, we use GDAL resampling with coordinates transform
QgsRectangle viewExtentInLayerCoordinate = renderContext()->extent();
// If view extent is infinite, we use the data provider extent
if ( viewExtentInLayerCoordinate.xMinimum() == std::numeric_limits<double>::lowest() &&
viewExtentInLayerCoordinate.yMinimum() == std::numeric_limits<double>::lowest() &&
viewExtentInLayerCoordinate.xMaximum() == std::numeric_limits<double>::max() &&
viewExtentInLayerCoordinate.yMaximum() == std::numeric_limits<double>::max() )
{
viewExtentInLayerCoordinate = dataProvider->extent();
}
double xLayerResol = viewExtentInLayerCoordinate.width() / static_cast<double>( viewWidth );
double yLayerResol = viewExtentInLayerCoordinate.height() / static_cast<double>( viewHeight );
double overSampling = 1;
if ( mPipe->resampleFilter() )
overSampling = mPipe->resampleFilter()->maxOversampling();
if ( dataProvider->capabilities() & QgsRasterDataProvider::Size )
{
// If the dataprovider has size capability, we calculate the requested resolution to provider
double providerXResol = dataProvider->extent().width() / dataProvider->xSize();
double providerYResol = dataProvider->extent().height() / dataProvider->ySize();
overSampling = ( xLayerResol / providerXResol + yLayerResol / providerYResol ) / 2;
}
GDALResampleAlg alg;
if ( overSampling > 1 )
alg = QgsGdalUtils::gdalResamplingAlgorithm( dataProvider->zoomedOutResamplingMethod() );
else
alg = QgsGdalUtils::gdalResamplingAlgorithm( dataProvider->zoomedInResamplingMethod() );
Qgis::DataType dataType = dataProvider->dataType( mElevationBand );
if ( dataType != Qgis::DataType::UnknownDataType ) // resampling data by GDAL is not coptible with unknown data type
{
// we need extra pixels on border to avoid effect border with resampling (at least 2 pixels band for cubic alg)
int sourceWidth = viewWidth + 4;
int sourceHeight = viewHeight + 4;
viewExtentInLayerCoordinate = QgsRectangle(
viewExtentInLayerCoordinate.xMinimum() - xLayerResol * 2,
viewExtentInLayerCoordinate.yMinimum() - yLayerResol * 2,
viewExtentInLayerCoordinate.xMaximum() + xLayerResol * 2,
viewExtentInLayerCoordinate.yMaximum() + yLayerResol * 2 );
// Now we can do the resampling
std::unique_ptr<QgsRasterBlock> sourcedata( dataProvider->block( mElevationBand, viewExtentInLayerCoordinate, sourceWidth, sourceHeight, mFeedback ) );
gdal::dataset_unique_ptr gdalDsInput =
QgsGdalUtils::blockToSingleBandMemoryDataset( viewExtentInLayerCoordinate, sourcedata.get() );
elevationBlock.reset( new QgsRasterBlock( dataType,
outputWidth,
outputHeight ) );
elevationBlock->setNoDataValue( dataProvider->sourceNoDataValue( mElevationBand ) );
gdal::dataset_unique_ptr gdalDsOutput =
QgsGdalUtils::blockToSingleBandMemoryDataset( mRasterViewPort->mDrawnExtent, elevationBlock.get() );
// For coordinate transformation, we try to obtain a coordinate operation string from the transform context.
// Depending of the CRS, if we can't we use GDAL transformation directly from the source and destination CRS
QString coordinateOperation;
const QgsCoordinateTransformContext &transformContext = renderContext()->transformContext();
if ( transformContext.mustReverseCoordinateOperation( mRasterViewPort->mDestCRS, mRasterViewPort->mSrcCRS ) )
coordinateOperation = transformContext.calculateCoordinateOperation( mRasterViewPort->mSrcCRS, mRasterViewPort->mDestCRS );
else
coordinateOperation = transformContext.calculateCoordinateOperation( mRasterViewPort->mDestCRS, mRasterViewPort->mSrcCRS );
if ( coordinateOperation.isEmpty() )
canRenderElevation = QgsGdalUtils::resampleSingleBandRaster( gdalDsInput.get(), gdalDsOutput.get(), alg,
mRasterViewPort->mSrcCRS, mRasterViewPort->mDestCRS );
else
canRenderElevation = QgsGdalUtils::resampleSingleBandRaster( gdalDsInput.get(), gdalDsOutput.get(), alg,
coordinateOperation.toUtf8().constData() );
}
}
if ( canRenderElevation )
{
QPoint topLeft;
if ( renderContext()->mapToPixel().mapRotation() != 0 )
{
// Now rendering elevation on the elevation map, we need to take care of rotation:
// again a resampling but this time with a geotransform.
const QgsMapToPixel &mtp = renderContext()->mapToPixel();
QgsElevationMap *elevMap = renderContext()->elevationMap();
int elevMapWidth = elevMap->rawElevationImage().width();
int elevMapHeight = elevMap->rawElevationImage().height();
int bottom = 0;
int top = elevMapHeight;
int left = elevMapWidth;
int right = 0;
QList<QgsPointXY> corners;
corners << QgsPointXY( mRasterViewPort->mDrawnExtent.xMinimum(), mRasterViewPort->mDrawnExtent.yMinimum() )
<< QgsPointXY( mRasterViewPort->mDrawnExtent.xMaximum(), mRasterViewPort->mDrawnExtent.yMaximum() )
<< QgsPointXY( mRasterViewPort->mDrawnExtent.xMinimum(), mRasterViewPort->mDrawnExtent.yMaximum() )
<< QgsPointXY( mRasterViewPort->mDrawnExtent.xMaximum(), mRasterViewPort->mDrawnExtent.yMinimum() );
for ( const QgsPointXY &corner : std::as_const( corners ) )
{
const QgsPointXY dpt = mtp.transform( corner );
int x = static_cast<int>( std::round( dpt.x() ) );
int y = static_cast<int>( std::round( dpt.y() ) );
if ( x < left )
left = x;
if ( x > right )
right = x;
if ( y < top )
top = y;
if ( y > bottom )
bottom = y;
}
const QgsPointXY origin = mtp.toMapCoordinates( left, top );
double gridXSize = mtp.toMapCoordinates( right, top ).distance( origin );
double gridYSize = mtp.toMapCoordinates( left, bottom ).distance( origin );
double angleRad = renderContext()->mapToPixel().mapRotation() / 180 * M_PI;
gdal::dataset_unique_ptr gdalDsInput =
QgsGdalUtils::blockToSingleBandMemoryDataset( mRasterViewPort->mDrawnExtent, elevationBlock.get() );
std::unique_ptr<QgsRasterBlock> rotatedElevationBlock =
std::make_unique<QgsRasterBlock>( elevationBlock->dataType(), right - left + 1, bottom - top + 1 );
rotatedElevationBlock->setNoDataValue( elevationBlock->noDataValue() );
gdal::dataset_unique_ptr gdalDsOutput =
QgsGdalUtils::blockToSingleBandMemoryDataset( angleRad, origin, gridXSize, gridYSize, rotatedElevationBlock.get() );
if ( QgsGdalUtils::resampleSingleBandRaster(
gdalDsInput.get(),
gdalDsOutput.get(),
QgsGdalUtils::gdalResamplingAlgorithm( dataProvider->zoomedInResamplingMethod() ), nullptr ) )
{
elevationBlock.reset( rotatedElevationBlock.release() );
}
topLeft = QPoint( left, top );
}
else
{
topLeft = mRasterViewPort->mTopLeftPoint.toQPointF().toPoint();
}
renderContext()->elevationMap()->fillWithRasterBlock(
elevationBlock.get(),
topLeft.y(),
topLeft.x(),
mElevationScale,
mElevationOffset );
}
}
}