Raster label precision: round to power of 10

qgis · Oct 6, 2020 · f6507d3 · f6507d3
1 parent 0d4dfc4
commit f6507d3
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Showing 5 changed files with 77 additions and 43 deletions.
diff --git a/src/gui/qgsguiutils.cpp b/src/gui/qgsguiutils.cpp
@@ -275,6 +275,48 @@ namespace QgsGuiUtils
     }
     return QSize( adjustedSize, adjustedSize );
   }
+
+  QString displayValue( const Qgis::DataType rasterDataType, const double value )
+  {
+
+    int precision { 9 };
+    switch ( rasterDataType )
+    {
+      case Qgis::DataType::Int16:
+      case Qgis::DataType::UInt16:
+      {
+        precision = 5;
+        break;
+      }
+      case Qgis::DataType::Int32:
+      case Qgis::DataType::UInt32:
+      {
+        precision = 10;
+        break;
+      }
+      case Qgis::DataType::Byte:
+      {
+        precision = 3;
+        break;
+      }
+      case Qgis::DataType::Float32:
+      {
+        precision = 9;
+        break;
+      }
+      case Qgis::DataType::Float64:
+      {
+        precision = 17;
+        break;
+      }
+      default:
+      {
+        precision = 9;
+      }
+    }
+    return QLocale().toString( value, 'f', precision );
+  }
+
 }
 
 //

diff --git a/src/gui/qgsguiutils.h b/src/gui/qgsguiutils.h
@@ -20,6 +20,7 @@
 #include <QWidget>
 #include <QStringList>
 #include "qgis_gui.h"
+#include "qgis.h"
 
 #define SIP_NO_FILE
 
@@ -189,6 +190,14 @@ namespace QgsGuiUtils
    * \since QGIS 3.8
    */
   QSize GUI_EXPORT panelIconSize( QSize size );
+
+  /**
+   * Returns a localized string representation of the \a value with the appropriate number of
+   * decimals supported by the \a rasterDataType.
+   * \since QGIS 3.16
+   */
+  QString displayValue( const Qgis::DataType rasterDataType, const double value );
+
 }
 
 /**

diff --git a/src/gui/raster/qgscolorrampshaderwidget.cpp b/src/gui/raster/qgscolorrampshaderwidget.cpp
@@ -31,6 +31,7 @@
 #include "qgscolordialog.h"
 #include "qgsrasterrendererutils.h"
 #include "qgsfileutils.h"
+#include "qgsguiutils.h"
 
 #include <QCursor>
 #include <QPushButton>
@@ -101,10 +102,10 @@ QgsColorRampShaderWidget::QgsColorRampShaderWidget( QWidget *parent )
   connect( btnColorRamp, &QgsColorRampButton::colorRampChanged, this, &QgsColorRampShaderWidget::applyColorRamp );
   connect( mNumberOfEntriesSpinBox, static_cast < void ( QSpinBox::* )( int ) > ( &QSpinBox::valueChanged ), this, &QgsColorRampShaderWidget::classify );
   connect( mClipCheckBox, &QAbstractButton::toggled, this, &QgsColorRampShaderWidget::widgetChanged );
-  connect( mLabelPrecisionRawData, &QCheckBox::toggled, this, [ = ]
+  connect( mLabelPrecisionUseDefault, &QCheckBox::toggled, this, [ = ]
   {
     autoLabel();
-    mPrecisionSpinBox->setEnabled( ! mLabelPrecisionRawData->isChecked() );
+    mPrecisionSpinBox->setEnabled( ! mLabelPrecisionUseDefault->isChecked() );
   } );
   connect( mPrecisionSpinBox, qgis::overload<int>::of( &QSpinBox::valueChanged ), this, [ = ]( int ) { autoLabel(); } );
 }
@@ -174,14 +175,23 @@ void QgsColorRampShaderWidget::autoLabel()
   QString label;
   int topLevelItemCount = mColormapTreeWidget->topLevelItemCount();
 
-  auto applyPrecision = [ = ]( QString value )
+  auto applyPrecision = [ = ]( const QString & value )
   {
-    // TODO: rounding to powers of 10
-    if ( ! mLabelPrecisionRawData->isChecked() )
+    double val { QLocale().toDouble( value ) };
+    if ( ! mLabelPrecisionUseDefault->isChecked() )
     {
-      value = QLocale().toString( QLocale().toDouble( value ), 'f', mPrecisionSpinBox->value() );
+      if ( mPrecisionSpinBox->value() <  0 )
+      {
+        const double factor { std::pow( 10, - mPrecisionSpinBox->value() ) };
+        val = static_cast<qlonglong>( val / factor ) * factor;
+        return QLocale().toString( val, 'f', 0 );
+      }
+      return QLocale().toString( val, 'f', mPrecisionSpinBox->value() );
+    }
+    else
+    {
+      return QgsGuiUtils::displayValue( mRasterDataProvider->dataType( mBand ), val );
     }
-    return value;
   };
 
   QTreeWidgetItem *currentItem = nullptr;

diff --git a/src/gui/raster/qgssinglebandpseudocolorrendererwidget.cpp b/src/gui/raster/qgssinglebandpseudocolorrendererwidget.cpp
@@ -25,6 +25,7 @@
 #include "qgstreewidgetitem.h"
 #include "qgssettings.h"
 #include "qgsmapcanvas.h"
+#include "qgsguiutils.h"
 
 // for color ramps - todo add rasterStyle and refactor raster vs. vector ramps
 #include "qgsstyle.h"
@@ -280,43 +281,13 @@ void QgsSingleBandPseudoColorRendererWidget::minMaxModified()
 
 QString QgsSingleBandPseudoColorRendererWidget::displayValue( const double value )
 {
-  int precision { 9 };
   if ( mRasterLayer->dataProvider() )
   {
-    switch ( mRasterLayer->dataProvider()->dataType( mBandComboBox->currentBand() ) )
-    {
-      case Qgis::DataType::Int16:
-      case Qgis::DataType::UInt16:
-      {
-        precision = 5;
-        break;
-      }
-      case Qgis::DataType::Int32:
-      case Qgis::DataType::UInt32:
-      {
-        precision = 10;
-        break;
-      }
-      case Qgis::DataType::Byte:
-      {
-        precision = 3;
-        break;
-      }
-      case Qgis::DataType::Float32:
-      {
-        precision = 9;
-        break;
-      }
-      case Qgis::DataType::Float64:
-      {
-        precision = 17;
-        break;
-      }
-      default:
-      {
-        precision = 9;
-      }
-    }
+    return QgsGuiUtils::displayValue( mRasterLayer->dataProvider()->dataType( mBandComboBox->currentBand() ), value );
+  }
+  else
+  {
+    // Use QLocale default
+    return QLocale().toString( value, 'g' );
   }
-  return QLocale().toString( value, 'g', precision );
 }
diff --git a/src/providers/postgres/raster/qgspostgresrasterutils.h b/src/providers/postgres/raster/qgspostgresrasterutils.h
@@ -16,8 +16,10 @@
 #ifndef QGSPOSTGRESRASTERUTILS_H
 #define QGSPOSTGRESRASTERUTILS_H
 
+#include "qgis.h"
 #include <QVariantMap>
 
+
 //! Raster utility functions
 struct QgsPostgresRasterUtils
 {