rasterlayerrenderer: Store min max computation as QgsRenderedItemDetails

qgis · Nov 14, 2024 · be05cf5 · be05cf5
1 parent a421114
commit be05cf5
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Showing 4 changed files with 27 additions and 11 deletions.
diff --git a/src/core/raster/qgsrasterlayer.cpp b/src/core/raster/qgsrasterlayer.cpp
@@ -1544,7 +1544,7 @@ void QgsRasterLayer::refreshContrastEnhancement( const QgsRectangle &extent )
 }
 
 bool QgsRasterLayer::refreshRendererIfNeeded( QgsRasterRenderer *rasterRenderer,
-    const QgsRectangle &extent )
+    const QgsRectangle &extent, double &min, double &max )
 {
   QGIS_PROTECT_QOBJECT_THREAD_ACCESS
 
@@ -1553,17 +1553,20 @@ bool QgsRasterLayer::refreshRendererIfNeeded( QgsRasterRenderer *rasterRenderer,
        rasterRenderer->minMaxOrigin().limits() != QgsRasterMinMaxOrigin::None &&
        rasterRenderer->minMaxOrigin().extent() == QgsRasterMinMaxOrigin::UpdatedCanvas )
   {
-    return refreshRenderer( rasterRenderer, extent );
+    return refreshRenderer( rasterRenderer, extent, min, max );
   }
 
   return false;
 }
 
-bool QgsRasterLayer::refreshRenderer( QgsRasterRenderer *rasterRenderer, const QgsRectangle &extent )
+bool QgsRasterLayer::refreshRenderer( QgsRasterRenderer *rasterRenderer, const QgsRectangle &extent, double &min, double &max )
 {
   QGIS_PROTECT_QOBJECT_THREAD_ACCESS
 
+  min = std::numeric_limits<double>::quiet_NaN();
+  max = std::numeric_limits<double>::quiet_NaN();
   bool refreshed = false;
+
   if ( mDataProvider )
   {
     QgsSingleBandGrayRenderer *singleBandRenderer = nullptr;
@@ -1581,8 +1584,6 @@ bool QgsRasterLayer::refreshRenderer( QgsRasterRenderer *rasterRenderer, const Q
     else if ( ( sbpcr = dynamic_cast<QgsSingleBandPseudoColorRenderer *>( rasterRenderer ) ) )
     {
       mLastRectangleUsedByRefreshContrastEnhancementIfNeeded = extent;
-      double min;
-      double max;
       computeMinMax( sbpcr->inputBand(),
                      rasterRenderer->minMaxOrigin(),
                      rasterRenderer->minMaxOrigin().limits(), extent,
@@ -1700,8 +1701,10 @@ bool QgsRasterLayer::setSubsetString( const QString &subset )
 
   if ( res )
   {
+    double min;
+    double max;
     setExtent( mDataProvider->extent() );
-    refreshRenderer( renderer(), extent() );
+    refreshRenderer( renderer(), extent(), min, max );
     emit subsetStringChanged();
   }
 

diff --git a/src/core/raster/qgsrasterlayer.h b/src/core/raster/qgsrasterlayer.h
@@ -408,7 +408,7 @@ class CORE_EXPORT QgsRasterLayer : public QgsMapLayer, public QgsAbstractProfile
      * \returns true if the renderer has been refreshed.
      * \note not available in Python bindings
      */
-    bool refreshRendererIfNeeded( QgsRasterRenderer *rasterRenderer, const QgsRectangle &extent ) SIP_SKIP;
+    bool refreshRendererIfNeeded( QgsRasterRenderer *rasterRenderer, const QgsRectangle &extent, double &min, double &max ) SIP_SKIP;
 
     /**
      * Returns the string (typically sql) used to define a subset of the layer.
@@ -527,9 +527,10 @@ class CORE_EXPORT QgsRasterLayer : public QgsMapLayer, public QgsAbstractProfile
 
     /**
      * \brief Refresh renderer with new extent
+     * Min - max values are set if the renderer relies on it. Otherwise, they are set to NaN.
      * \returns true if the renderer has been refreshed.
      */
-    bool refreshRenderer( QgsRasterRenderer *rasterRenderer, const QgsRectangle &extent );
+    bool refreshRenderer( QgsRasterRenderer *rasterRenderer, const QgsRectangle &extent, double &min, double &max );
 
     void computeMinMax( int band,
                         const QgsRasterMinMaxOrigin &mmo,

diff --git a/src/core/raster/qgsrasterlayerrenderer.cpp b/src/core/raster/qgsrasterlayerrenderer.cpp
@@ -39,10 +39,13 @@
 #include "qgsinterval.h"
 #include "qgsunittypes.h"
 #include "qgsrasternuller.h"
+#include "qgsrenderedcalculatedresults.h"
 
 #include <QElapsedTimer>
 #include <QPointer>
 #include <QThread>
+#include <cmath>
+#include <limits>
 
 ///@cond PRIVATE
 
@@ -273,7 +276,14 @@ QgsRasterLayerRenderer::QgsRasterLayerRenderer( QgsRasterLayer *layer, QgsRender
        && !( rendererContext.flags() & Qgis::RenderContextFlag::RenderPreviewJob )
        && !( rendererContext.flags() & Qgis::RenderContextFlag::Render3DMap ) )
   {
-    layer->refreshRendererIfNeeded( rasterRenderer, rendererContext.extent() );
+    double min = std::numeric_limits<double>::quiet_NaN();
+    double max = std::numeric_limits<double>::quiet_NaN();
+    if ( layer->refreshRendererIfNeeded( rasterRenderer, rendererContext.extent(), min, max ) && !std::isnan( min ) && !std::isnan( max ) )
+    {
+      QgsRenderedCalculatedResults *computedResults = new QgsRenderedCalculatedResults( layer->id(), min, max );
+      computedResults->setBoundingBox( rendererContext.extent() );
+      appendRenderedItemDetails( computedResults );
+    }
   }
 
   mPipe->evaluateDataDefinedProperties( rendererContext.expressionContext() );

diff --git a/tests/src/core/testqgsrasterlayer.cpp b/tests/src/core/testqgsrasterlayer.cpp
@@ -1007,7 +1007,9 @@ void TestQgsRasterLayer::testRefreshRendererIfNeeded()
 
   // Should do nothing
   const QgsRectangle newExtent = QgsRectangle( 785000, 3340000, 785100, 3340100 );
-  const bool refreshed = mpLandsatRasterLayer->refreshRendererIfNeeded( mpLandsatRasterLayer->renderer(), newExtent );
+  double min;
+  double max;
+  const bool refreshed = mpLandsatRasterLayer->refreshRendererIfNeeded( mpLandsatRasterLayer->renderer(), newExtent, min, max );
   QVERIFY( !refreshed );
   QCOMPARE( mpLandsatRasterLayer->renderer()->minMaxOrigin().limits(), QgsRasterMinMaxOrigin::MinMax );
   const double minVal = static_cast<QgsMultiBandColorRenderer *>( mpLandsatRasterLayer->renderer() )->redContrastEnhancement()->minimumValue();
@@ -1019,7 +1021,7 @@ void TestQgsRasterLayer::testRefreshRendererIfNeeded()
   mmo.setStatAccuracy( QgsRasterMinMaxOrigin::Exact );
   mpLandsatRasterLayer->renderer()->setMinMaxOrigin( mmo );
   QCOMPARE( mpLandsatRasterLayer->renderer()->minMaxOrigin().extent(), QgsRasterMinMaxOrigin::UpdatedCanvas );
-  const bool newRefreshed = mpLandsatRasterLayer->refreshRendererIfNeeded( mpLandsatRasterLayer->renderer(), newExtent );
+  const bool newRefreshed = mpLandsatRasterLayer->refreshRendererIfNeeded( mpLandsatRasterLayer->renderer(), newExtent, min, max );
   QVERIFY( newRefreshed );
   const double newMinVal = static_cast<QgsMultiBandColorRenderer *>( mpLandsatRasterLayer->renderer() )->redContrastEnhancement()->minimumValue();
   QGSCOMPARENOTNEAR( initMinVal, newMinVal, 1e-5 );