QgsRasterLayerRenderer::QgsRasterLayerRenderer( QgsRasterLayer* layer, QgsRenderContext& rendererContext )
: QgsMapLayerRenderer( layer->id() )
, mRasterViewPort( nullptr )
, mPipe( nullptr )
{
mPainter = rendererContext.painter();
const QgsMapToPixel& theQgsMapToPixel = rendererContext.mapToPixel();
mMapToPixel = &theQgsMapToPixel;
QgsMapToPixel mapToPixel = theQgsMapToPixel;
if ( 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
QgsPoint center = mapToPixel.toMapCoordinates(
mapToPixel.mapWidth() / 2.0,
mapToPixel.mapHeight() / 2.0
);
mapToPixel.setMapRotation( 0, center.x(), center.y() );
}
QgsRectangle myProjectedViewExtent;
QgsRectangle myProjectedLayerExtent;
if ( rendererContext.coordinateTransform() )
{
QgsDebugMsg( "coordinateTransform set -> project extents." );
try
{
myProjectedViewExtent = rendererContext.coordinateTransform()->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
{
myProjectedLayerExtent = rendererContext.coordinateTransform()->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
{
QgsDebugMsg( "coordinateTransform not set" );
myProjectedViewExtent = rendererContext.extent();
myProjectedLayerExtent = layer->extent();
}
// clip raster extent to view extent
QgsRectangle myRasterExtent = myProjectedViewExtent.intersect( &myProjectedLayerExtent );
if ( myRasterExtent.isEmpty() )
{
QgsDebugMsg( "draw request outside view extent." );
// nothing to do
return;
}
QgsDebugMsg( "theViewExtent is " + rendererContext.extent().toString() );
QgsDebugMsg( "myProjectedViewExtent is " + myProjectedViewExtent.toString() );
QgsDebugMsg( "myProjectedLayerExtent is " + myProjectedLayerExtent.toString() );
QgsDebugMsg( "myRasterExtent is " + myRasterExtent.toString() );
//
// 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() )
{
mRasterViewPort->mSrcCRS = layer->crs();
mRasterViewPort->mDestCRS = rendererContext.coordinateTransform()->destCRS();
mRasterViewPort->mSrcDatumTransform = rendererContext.coordinateTransform()->sourceDatumTransform();
mRasterViewPort->mDestDatumTransform = rendererContext.coordinateTransform()->destinationDatumTransform();
}
else
{
mRasterViewPort->mSrcCRS = QgsCoordinateReferenceSystem(); // will be invalid
mRasterViewPort->mDestCRS = QgsCoordinateReferenceSystem(); // will be invalid
mRasterViewPort->mSrcDatumTransform = -1;
mRasterViewPort->mDestDatumTransform = -1;
}
// 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. 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( floor( mRasterViewPort->mTopLeftPoint.x() ) );
mRasterViewPort->mTopLeftPoint.setY( floor( mRasterViewPort->mTopLeftPoint.y() ) );
mRasterViewPort->mBottomRightPoint.setX( ceil( mRasterViewPort->mBottomRightPoint.x() ) );
mRasterViewPort->mBottomRightPoint.setY( ceil( mRasterViewPort->mBottomRightPoint.y() ) );
// recalc myRasterExtent to aligned values
myRasterExtent.set(
mapToPixel.toMapCoordinatesF( mRasterViewPort->mTopLeftPoint.x(),
mRasterViewPort->mBottomRightPoint.y() ),
mapToPixel.toMapCoordinatesF( mRasterViewPort->mBottomRightPoint.x(),
mRasterViewPort->mTopLeftPoint.y() )
);
//raster viewport top left / bottom right are already rounded to int
mRasterViewPort->mWidth = static_cast<int>( mRasterViewPort->mBottomRightPoint.x() - mRasterViewPort->mTopLeftPoint.x() );
mRasterViewPort->mHeight = static_cast<int>( mRasterViewPort->mBottomRightPoint.y() - mRasterViewPort->mTopLeftPoint.y() );
//the drawable area can start to get very very large when you get down displaying 2x2 or smaller, this is becasue
//mapToPixel.mapUnitsPerPixel() is less then 1,
//so we will just get the pixel data and then render these special cases differently in paintImageToCanvas()
QgsDebugMsgLevel( QString( "mapUnitsPerPixel = %1" ).arg( mapToPixel.mapUnitsPerPixel() ), 3 );
QgsDebugMsgLevel( QString( "mWidth = %1" ).arg( layer->width() ), 3 );
QgsDebugMsgLevel( QString( "mHeight = %1" ).arg( layer->height() ), 3 );
QgsDebugMsgLevel( QString( "myRasterExtent.xMinimum() = %1" ).arg( myRasterExtent.xMinimum() ), 3 );
QgsDebugMsgLevel( QString( "myRasterExtent.xMaximum() = %1" ).arg( myRasterExtent.xMaximum() ), 3 );
QgsDebugMsgLevel( QString( "myRasterExtent.yMinimum() = %1" ).arg( myRasterExtent.yMinimum() ), 3 );
QgsDebugMsgLevel( QString( "myRasterExtent.yMaximum() = %1" ).arg( myRasterExtent.yMaximum() ), 3 );
QgsDebugMsgLevel( QString( "mTopLeftPoint.x() = %1" ).arg( mRasterViewPort->mTopLeftPoint.x() ), 3 );
QgsDebugMsgLevel( QString( "mBottomRightPoint.x() = %1" ).arg( mRasterViewPort->mBottomRightPoint.x() ), 3 );
QgsDebugMsgLevel( QString( "mTopLeftPoint.y() = %1" ).arg( mRasterViewPort->mTopLeftPoint.y() ), 3 );
QgsDebugMsgLevel( QString( "mBottomRightPoint.y() = %1" ).arg( mRasterViewPort->mBottomRightPoint.y() ), 3 );
QgsDebugMsgLevel( QString( "mWidth = %1" ).arg( mRasterViewPort->mWidth ), 3 );
QgsDebugMsgLevel( QString( "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( rendererContext.rasterScaleFactor() * 25.4 * rendererContext.scaleFactor() );
// copy the whole raster pipe!
mPipe = new QgsRasterPipe( *layer->pipe() );
}
