Merge pull request #4207 from nyalldawson/cancel_job

Backport non-blocking render cancellation
qgis · Mar 2, 2017 · 0d17e85 · 0d17e85
2 parents 3057738 + a4219b3
commit 0d17e85
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Showing 14 changed files with 183 additions and 11 deletions.
diff --git a/python/core/qgsmaprenderercustompainterjob.sip b/python/core/qgsmaprenderercustompainterjob.sip
@@ -19,6 +19,7 @@ class QgsMapRendererCustomPainterJob : QgsMapRendererJob
 
     virtual void start();
     virtual void cancel();
+    virtual void cancelWithoutBlocking();
     virtual void waitForFinished();
     virtual bool isActive() const;
     virtual QgsLabelingResults* takeLabelingResults() /Transfer/;

diff --git a/python/core/qgsmaprendererjob.sip b/python/core/qgsmaprendererjob.sip
@@ -56,6 +56,8 @@ class QgsMapRendererJob : QObject
     //! Does nothing if the rendering is not active.
     virtual void cancel() = 0;
 
+    virtual void cancelWithoutBlocking() = 0;
+
     //! Block until the job has finished.
     virtual void waitForFinished() = 0;
 

diff --git a/python/core/qgsmaprendererparalleljob.sip b/python/core/qgsmaprendererparalleljob.sip
@@ -18,6 +18,7 @@ class QgsMapRendererParallelJob : QgsMapRendererQImageJob
 
     virtual void start();
     virtual void cancel();
+    virtual void cancelWithoutBlocking();
     virtual void waitForFinished();
     virtual bool isActive() const;
 

diff --git a/python/core/qgsmaprenderersequentialjob.sip b/python/core/qgsmaprenderersequentialjob.sip
@@ -19,6 +19,7 @@ class QgsMapRendererSequentialJob : QgsMapRendererQImageJob
 
     virtual void start();
     virtual void cancel();
+    virtual void cancelWithoutBlocking();
     virtual void waitForFinished();
     virtual bool isActive() const;
 

diff --git a/src/core/qgsmaprenderercustompainterjob.cpp b/src/core/qgsmaprenderercustompainterjob.cpp
@@ -126,14 +126,7 @@ void QgsMapRendererCustomPainterJob::cancel()
 
   QgsDebugMsg( "QPAINTER cancelling" );
   disconnect( &mFutureWatcher, SIGNAL( finished() ), this, SLOT( futureFinished() ) );
-
-  mLabelingRenderContext.setRenderingStopped( true );
-  for ( LayerRenderJobs::iterator it = mLayerJobs.begin(); it != mLayerJobs.end(); ++it )
-  {
-    it->context.setRenderingStopped( true );
-    if ( it->renderer && it->renderer->feedback() )
-      it->renderer->feedback()->cancel();
-  }
+  cancelWithoutBlocking();
 
   QTime t;
   t.start();
@@ -144,7 +137,24 @@ void QgsMapRendererCustomPainterJob::cancel()
 
   futureFinished();
 
-  QgsDebugMsg( "QPAINTER cancelled" );
+  QgsDebugMsg( "QPAINTER canceled" );
+}
+
+void QgsMapRendererCustomPainterJob::cancelWithoutBlocking()
+{
+  if ( !isActive() )
+  {
+    QgsDebugMsg( "QPAINTER not running!" );
+    return;
+  }
+
+  mLabelingRenderContext.setRenderingStopped( true );
+  for ( LayerRenderJobs::iterator it = mLayerJobs.begin(); it != mLayerJobs.end(); ++it )
+  {
+    it->context.setRenderingStopped( true );
+    if ( it->renderer && it->renderer->feedback() )
+      it->renderer->feedback()->cancel();
+  }
 }
 
 void QgsMapRendererCustomPainterJob::waitForFinished()

diff --git a/src/core/qgsmaprenderercustompainterjob.h b/src/core/qgsmaprenderercustompainterjob.h
@@ -38,6 +38,7 @@ class CORE_EXPORT QgsMapRendererCustomPainterJob : public QgsMapRendererJob
 
     virtual void start() override;
     virtual void cancel() override;
+    virtual void cancelWithoutBlocking() override;
     virtual void waitForFinished() override;
     virtual bool isActive() const override;
     virtual QgsLabelingResults* takeLabelingResults() override;

diff --git a/src/core/qgsmaprendererjob.h b/src/core/qgsmaprendererjob.h
@@ -96,6 +96,13 @@ class CORE_EXPORT QgsMapRendererJob : public QObject
     //! Does nothing if the rendering is not active.
     virtual void cancel() = 0;
 
+    /**
+     * Triggers cancelation of the rendering job without blocking. The render job will continue
+     * to operate until it is able to cancel, at which stage the finished() signal will be emitted.
+     * Does nothing if the rendering is not active.
+     */
+    virtual void cancelWithoutBlocking() = 0;
+
     //! Block until the job has finished.
     virtual void waitForFinished() = 0;
 
@@ -206,6 +213,7 @@ class CORE_EXPORT QgsMapRendererQImageJob : public QgsMapRendererJob
 
     //! Get a preview/resulting image
     virtual QImage renderedImage() = 0;
+
 };
 
 

diff --git a/src/core/qgsmaprendererparalleljob.cpp b/src/core/qgsmaprendererparalleljob.cpp
@@ -123,6 +123,28 @@ void QgsMapRendererParallelJob::cancel()
   Q_ASSERT( mStatus == Idle );
 }
 
+void QgsMapRendererParallelJob::cancelWithoutBlocking()
+{
+  if ( !isActive() )
+    return;
+
+  QgsDebugMsg( QString( "PARALLEL cancel at status %1" ).arg( mStatus ) );
+
+  mLabelingRenderContext.setRenderingStopped( true );
+  for ( LayerRenderJobs::iterator it = mLayerJobs.begin(); it != mLayerJobs.end(); ++it )
+  {
+    it->context.setRenderingStopped( true );
+    if ( it->renderer && it->renderer->feedback() )
+      it->renderer->feedback()->cancel();
+  }
+
+  if ( mStatus == RenderingLayers )
+  {
+    disconnect( &mFutureWatcher, SIGNAL( finished() ), this, SLOT( renderLayersFinished() ) );
+    connect( &mFutureWatcher, SIGNAL( finished() ), this, SLOT( renderingFinished() ) );
+  }
+}
+
 void QgsMapRendererParallelJob::waitForFinished()
 {
   if ( !isActive() )

diff --git a/src/core/qgsmaprendererparalleljob.h b/src/core/qgsmaprendererparalleljob.h
@@ -35,6 +35,7 @@ class CORE_EXPORT QgsMapRendererParallelJob : public QgsMapRendererQImageJob
 
     virtual void start() override;
     virtual void cancel() override;
+    virtual void cancelWithoutBlocking() override;
     virtual void waitForFinished() override;
     virtual bool isActive() const override;
 

diff --git a/src/core/qgsmaprenderersequentialjob.cpp b/src/core/qgsmaprenderersequentialjob.cpp
@@ -86,6 +86,15 @@ void QgsMapRendererSequentialJob::cancel()
   Q_ASSERT( !mInternalJob && !mPainter );
 }
 
+void QgsMapRendererSequentialJob::cancelWithoutBlocking()
+{
+  if ( !isActive() )
+    return;
+
+  QgsDebugMsg( "sequential - cancel internal" );
+  mInternalJob->cancelWithoutBlocking();
+}
+
 void QgsMapRendererSequentialJob::waitForFinished()
 {
   if ( !isActive() )

diff --git a/src/core/qgsmaprenderersequentialjob.h b/src/core/qgsmaprenderersequentialjob.h
@@ -37,6 +37,7 @@ class CORE_EXPORT QgsMapRendererSequentialJob : public QgsMapRendererQImageJob
 
     virtual void start() override;
     virtual void cancel() override;
+    virtual void cancelWithoutBlocking() override;
     virtual void waitForFinished() override;
     virtual bool isActive() const override;
 

diff --git a/src/gui/qgsmapcanvas.cpp b/src/gui/qgsmapcanvas.cpp
@@ -835,8 +835,10 @@ void QgsMapCanvas::stopRendering()
   {
     QgsDebugMsg( "CANVAS stop rendering!" );
     mJobCancelled = true;
-    mJob->cancel();
-    Q_ASSERT( !mJob ); // no need to delete here: already deleted in finished()
+    disconnect( mJob, SIGNAL( finished() ), this, SLOT( rendererJobFinished() ) );
+    connect( mJob, SIGNAL( finished() ), mJob, SLOT( deleteLater() ) );
+    mJob->cancelWithoutBlocking();
+    mJob = nullptr;
   }
 }
 

diff --git a/tests/src/python/CMakeLists.txt b/tests/src/python/CMakeLists.txt
@@ -57,6 +57,7 @@ ADD_PYTHON_TEST(PyQgsGeometryValidator test_qgsgeometryvalidator.py)
 ADD_PYTHON_TEST(PyQgsGraduatedSymbolRendererV2 test_qgsgraduatedsymbolrendererv2.py)
 ADD_PYTHON_TEST(PyQgsInterval test_qgsinterval.py)
 ADD_PYTHON_TEST(PyQgsJSONUtils test_qgsjsonutils.py)
+ADD_PYTHON_TEST(PyQgsMapRenderer test_qgsmaprenderer.py)
 ADD_PYTHON_TEST(PyQgsMapUnitScale test_qgsmapunitscale.py)
 ADD_PYTHON_TEST(PyQgsMemoryProvider test_provider_memory.py)
 ADD_PYTHON_TEST(PyQgsMultiEditToolButton test_qgsmultiedittoolbutton.py)

diff --git a/tests/src/python/test_qgsmaprenderer.py b/tests/src/python/test_qgsmaprenderer.py
@@ -0,0 +1,112 @@
+# -*- coding: utf-8 -*-
+"""QGIS Unit tests for QgsMapRenderer.
+
+.. note:: 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.
+"""
+__author__ = 'Nyall Dawson'
+__date__ = '1/02/2017'
+__copyright__ = 'Copyright 2017, The QGIS Project'
+# This will get replaced with a git SHA1 when you do a git archive
+__revision__ = '$Format:%H$'
+
+import qgis  # NOQA
+
+from qgis.core import (QgsMapRendererCache,
+                       QgsMapRendererParallelJob,
+                       QgsMapRendererSequentialJob,
+                       QgsMapRendererCustomPainterJob,
+                       QgsRectangle,
+                       QgsVectorLayer,
+                       QgsProject,
+                       QgsFeature,
+                       QgsGeometry,
+                       QgsMapSettings,
+                       QgsPoint)
+from qgis.testing import start_app, unittest
+from qgis.PyQt.QtCore import QSize, QThreadPool
+from qgis.PyQt.QtGui import QPainter, QImage
+from random import uniform
+
+
+app = start_app()
+
+
+class TestQgsMapRenderer(unittest.TestCase):
+
+    def setUp(self):
+        pass
+
+    def tearDown(self):
+        # avoid crash on finish, probably related to https://bugreports.qt.io/browse/QTBUG-35760
+        QThreadPool.globalInstance().waitForDone()
+
+    def checkCancel(self, job_type):
+        """test canceling a render job"""
+        layer = QgsVectorLayer("Point?field=fldtxt:string",
+                               "layer1", "memory")
+
+        # add a ton of random points
+        for i in range(2000):
+            x = uniform(5, 25)
+            y = uniform(25, 45)
+            g = QgsGeometry.fromPoint(QgsPoint(x, y))
+            f = QgsFeature()
+            f.setGeometry(g)
+            f.initAttributes(1)
+            layer.dataProvider().addFeatures([f])
+
+        settings = QgsMapSettings()
+        settings.setExtent(QgsRectangle(5, 25, 25, 45))
+        settings.setOutputSize(QSize(600, 400))
+        settings.setLayers([layer.id()])
+
+        # first try non-blocking cancelWithoutBlocking() call
+        job = job_type(settings)
+        job.start()
+
+        # insta cancel!
+        job.cancelWithoutBlocking()
+        # should still be active immediately after
+        self.assertTrue(job.isActive())
+
+        while job.isActive():
+            app.processEvents()
+
+        # try blocking cancel() call
+        job = job_type(settings)
+        job.start()
+
+        # insta cancel!
+        job.cancel()
+        # should not be active anymore
+        self.assertFalse(job.isActive())
+
+    def runRendererChecks(self, renderer):
+        """ runs all checks on the specified renderer """
+        self.checkCancel(renderer)
+
+    def testParallelRenderer(self):
+        """ run test suite on QgsMapRendererParallelJob"""
+        self.runRendererChecks(QgsMapRendererParallelJob)
+
+    def testSequentialRenderer(self):
+        """ run test suite on QgsMapRendererSequentialJob"""
+        self.runRendererChecks(QgsMapRendererSequentialJob)
+
+    def testCustomPainterRenderer(self):
+        """ run test suite on QgsMapRendererCustomPainterJob"""
+        im = QImage(200, 200, QImage.Format_RGB32)
+        p = QPainter(im)
+
+        def create_job(settings):
+            return QgsMapRendererCustomPainterJob(settings, p)
+
+        self.runRendererChecks(create_job)
+        p.end()
+
+
+if __name__ == '__main__':
+    unittest.main()