Add QgsFeedback to handle canceling rendering

qgis · Apr 8, 2021 · 4a0230f · 4a0230f
1 parent b01deeb
commit 4a0230f
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Showing 7 changed files with 53 additions and 28 deletions.
diff --git a/python/core/auto_generated/pointcloud/qgspointcloudrenderer.sip.in b/python/core/auto_generated/pointcloud/qgspointcloudrenderer.sip.in
@@ -26,7 +26,7 @@ Encapsulates the render context for a 2D point cloud rendering operation.
   public:
 
     QgsPointCloudRenderContext( QgsRenderContext &context, const QgsVector3D &scale, const QgsVector3D &offset,
-                                double zValueScale, double zValueFixedOffset );
+                                double zValueScale, double zValueFixedOffset, QgsFeedback *feedback );
 %Docstring
 Constructor for QgsPointCloudRenderContext.
 
@@ -135,6 +135,13 @@ Returns any constant offset which must be applied to z values taken from the poi
    Scaling of z values via :py:func:`~QgsPointCloudRenderContext.zValueScale` should be applied before the :py:func:`~QgsPointCloudRenderContext.zValueFixedOffset`.
 %End
 
+    QgsFeedback *feedback() const;
+%Docstring
+Returns the feedback object used to cancel rendering
+
+.. versionadded:: 3.20
+%End
+
 
   private:
     QgsPointCloudRenderContext( const QgsPointCloudRenderContext &rh );

diff --git a/src/core/pointcloud/qgseptpointcloudindex.cpp b/src/core/pointcloud/qgseptpointcloudindex.cpp
@@ -126,9 +126,7 @@ bool QgsEptPointCloudIndex::loadSchema( const QByteArray &dataJson )
     return false;
 
   mSpan = result.value( QLatin1String( "span" ) ).toInt();
-  mPointCount = result.value( QLatin1String( "points" ) ).toInt();
-  if ( mPointCount == 0 )
-    mPointCount = result.value( QLatin1String( "points" ) ).toDouble();
+  mPointCount = std::min( ( double )std::numeric_limits<int>::max(), result.value( QLatin1String( "points" ) ).toDouble() );
 
   // WKT
   const QJsonObject srs = result.value( QLatin1String( "srs" ) ).toObject();

diff --git a/src/core/pointcloud/qgspointcloudlayerrenderer.cpp b/src/core/pointcloud/qgspointcloudlayerrenderer.cpp
@@ -39,6 +39,7 @@ QgsPointCloudLayerRenderer::QgsPointCloudLayerRenderer( QgsPointCloudLayer *laye
   : QgsMapLayerRenderer( layer->id(), &context )
   , mLayer( layer )
   , mLayerAttributes( layer->attributes() )
+  , mFeedback( new QgsFeedback )
 {
   // TODO: we must not keep pointer to mLayer (it's dangerous) - we must copy anything we need for rendering
   // or use some locking to prevent read/write from multiple threads
@@ -68,7 +69,7 @@ QgsPointCloudLayerRenderer::QgsPointCloudLayerRenderer( QgsPointCloudLayer *laye
 
 bool QgsPointCloudLayerRenderer::render()
 {
-  QgsPointCloudRenderContext context( *renderContext(), mScale, mOffset, mZScale, mZOffset );
+  QgsPointCloudRenderContext context( *renderContext(), mScale, mOffset, mZScale, mZOffset, mFeedback.get() );
 
   // Set up the render configuration options
   QPainter *painter = context.renderContext().painter();
@@ -241,12 +242,14 @@ int QgsPointCloudLayerRenderer::renderNodesAsync( const QVector<IndexedPointClou
   const int groupSize = 4;
   for ( int groupIndex = 0; groupIndex < nodes.size(); groupIndex += groupSize )
   {
+    if ( context.feedback()->isCanceled() )
+      break;
     // Async loading of nodes
     const int currentGroupSize = std::min( std::max( nodes.size() - groupIndex, 0 ), groupSize );
     QVector<QgsPointCloudBlockRequest *> blockRequests( currentGroupSize, nullptr );
     QVector<bool> finishedLoadingBlock( currentGroupSize, false );
     QEventLoop loop;
-
+    QObject::connect( context.feedback(), &QgsFeedback::canceled, &loop, &QEventLoop::quit );
     // Note: All capture by reference warnings here shouldn't be an issue since we have an event loop, so locals won't be deallocated
     for ( int i = 0; i < blockRequests.size(); ++i )
     {
@@ -269,31 +272,33 @@ int QgsPointCloudLayerRenderer::renderNodesAsync( const QVector<IndexedPointClou
     loop.exec();
 
     QgsDebugMsg( QStringLiteral( "Downloaded in : %1ms" ).arg( downloadTimer.elapsed() ) );
-
-    // Render all the point cloud blocks sequentially
-    for ( int i = 0; i < blockRequests.size(); ++i )
+    if ( !context.feedback()->isCanceled() )
     {
-      if ( context.renderContext().renderingStopped() )
+      // Render all the point cloud blocks sequentially
+      for ( int i = 0; i < blockRequests.size(); ++i )
       {
-        QgsDebugMsgLevel( "canceled", 2 );
-        canceled = true;
-        break;
-      }
+        if ( context.renderContext().renderingStopped() )
+        {
+          QgsDebugMsgLevel( "canceled", 2 );
+          canceled = true;
+          break;
+        }
 
-      if ( !blockRequests[ i ]->block() )
-        continue;
+        if ( !blockRequests[ i ]->block() )
+          continue;
 
-      context.setAttributes( blockRequests[ i ]->block()->attributes() );
+        context.setAttributes( blockRequests[ i ]->block()->attributes() );
 
-      mRenderer->renderBlock( blockRequests[ i ]->block(), context );
-      ++nodesDrawn;
+        mRenderer->renderBlock( blockRequests[ i ]->block(), context );
+        ++nodesDrawn;
 
-      // as soon as first block is rendered, we can start showing layer updates.
-      // but if we are blocking render updates (so that a previously cached image is being shown), we wait
-      // at most e.g. 3 seconds before we start forcing progressive updates.
-      if ( !mBlockRenderUpdates || mElapsedTimer.elapsed() > MAX_TIME_TO_USE_CACHED_PREVIEW_IMAGE )
-      {
-        mReadyToCompose = true;
+        // as soon as first block is rendered, we can start showing layer updates.
+        // but if we are blocking render updates (so that a previously cached image is being shown), we wait
+        // at most e.g. 3 seconds before we start forcing progressive updates.
+        if ( !mBlockRenderUpdates || mElapsedTimer.elapsed() > MAX_TIME_TO_USE_CACHED_PREVIEW_IMAGE )
+        {
+          mReadyToCompose = true;
+        }
       }
     }
 

diff --git a/src/core/pointcloud/qgspointcloudlayerrenderer.h b/src/core/pointcloud/qgspointcloudlayerrenderer.h
@@ -30,6 +30,7 @@
 #include "qgsidentifycontext.h"
 #include "qgspointcloudrenderer.h"
 #include "qgsmapclippingregion.h"
+#include "qgsrasterinterface.h"
 
 #include <QDomElement>
 #include <QString>
@@ -43,6 +44,8 @@ class QgsPointCloudRenderContext;
 
 #define SIP_NO_FILE
 
+///@endcond
+
 /**
  * \ingroup core
  *
@@ -65,6 +68,8 @@ class CORE_EXPORT QgsPointCloudLayerRenderer: public QgsMapLayerRenderer
     bool forceRasterRender() const override;
     void setLayerRenderingTimeHint( int time ) override;
 
+    QgsFeedback *feedback() const override { return mFeedback.get(); }
+
   private:
     QVector<IndexedPointCloudNode> traverseTree( const QgsPointCloudIndex *pc, const QgsRenderContext &context, IndexedPointCloudNode n, double maxErrorPixels, double nodeErrorPixels );
 
@@ -89,6 +94,7 @@ class CORE_EXPORT QgsPointCloudLayerRenderer: public QgsMapLayerRenderer
     bool mBlockRenderUpdates = false;
     QElapsedTimer mElapsedTimer;
 
+    std::unique_ptr<QgsFeedback> mFeedback = nullptr;
 };
 
 #endif // QGSPOINTCLOUDLAYERRENDERER_H
diff --git a/src/core/pointcloud/qgspointcloudrenderer.cpp b/src/core/pointcloud/qgspointcloudrenderer.cpp
@@ -27,12 +27,13 @@
 #include <QThread>
 #include <QPointer>
 
-QgsPointCloudRenderContext::QgsPointCloudRenderContext( QgsRenderContext &context, const QgsVector3D &scale, const QgsVector3D &offset, double zValueScale, double zValueFixedOffset )
+QgsPointCloudRenderContext::QgsPointCloudRenderContext( QgsRenderContext &context, const QgsVector3D &scale, const QgsVector3D &offset, double zValueScale, double zValueFixedOffset, QgsFeedback *feedback )
   : mRenderContext( context )
   , mScale( scale )
   , mOffset( offset )
   , mZValueScale( zValueScale )
   , mZValueFixedOffset( zValueFixedOffset )
+  , mFeedback( feedback )
 {
 
 }

diff --git a/src/core/pointcloud/qgspointcloudrenderer.h b/src/core/pointcloud/qgspointcloudrenderer.h
@@ -55,7 +55,7 @@ class CORE_EXPORT QgsPointCloudRenderContext
      * taken from the point cloud index.
      */
     QgsPointCloudRenderContext( QgsRenderContext &context, const QgsVector3D &scale, const QgsVector3D &offset,
-                                double zValueScale, double zValueFixedOffset );
+                                double zValueScale, double zValueFixedOffset, QgsFeedback *feedback );
 
     //! QgsPointCloudRenderContext cannot be copied.
     QgsPointCloudRenderContext( const QgsPointCloudRenderContext &rh ) = delete;
@@ -154,6 +154,13 @@ class CORE_EXPORT QgsPointCloudRenderContext
      */
     double zValueFixedOffset() const { return mZValueFixedOffset; }
 
+    /**
+     * Returns the feedback object used to cancel rendering
+     *
+     * \since QGIS 3.20
+     */
+    QgsFeedback *feedback() const { return mFeedback; }
+
 #ifndef SIP_RUN
 
     /**
@@ -208,6 +215,8 @@ class CORE_EXPORT QgsPointCloudRenderContext
     int mZOffset = 0;
     double mZValueScale = 1.0;
     double mZValueFixedOffset = 0;
+
+    QgsFeedback *mFeedback = nullptr;
 };
 
 

diff --git a/src/core/pointcloud/qgsremoteeptpointcloudindex.cpp b/src/core/pointcloud/qgsremoteeptpointcloudindex.cpp
@@ -96,7 +96,6 @@ void QgsRemoteEptPointCloudIndex::load( const QString &url )
 
 QgsPointCloudBlock *QgsRemoteEptPointCloudIndex::nodeData( const IndexedPointCloudNode &n, const QgsPointCloudRequest &request )
 {
-  qDebug() << __PRETTY_FUNCTION__ << " " << n.toString() << " start";
   std::unique_ptr<QgsPointCloudBlockRequest> blockRequest( asyncNodeData( n, request ) );
   if ( !blockRequest )
     return nullptr;