Remove checkbox for default precision

qgis · Oct 6, 2020 · 37d8421 · 37d8421
1 parent ce3588b
commit 37d8421
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Showing 5 changed files with 55 additions and 48 deletions.
diff --git a/src/gui/qgsguiutils.cpp b/src/gui/qgsguiutils.cpp
@@ -276,47 +276,45 @@ namespace QgsGuiUtils
     return QSize( adjustedSize, adjustedSize );
   }
 
-  QString displayValue( const Qgis::DataType rasterDataType, const double value )
+  QString displayValueWithMaximumDecimals( const Qgis::DataType rasterDataType, const double value )
   {
+    const int precision { significantDigits( rasterDataType ) };
+    // Reduce
+    return QLocale().toString( value, 'f', precision );
+  }
 
-    int precision { 9 };
+  int significantDigits( const Qgis::DataType rasterDataType )
+  {
     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:
+      case Qgis::DataType::CInt16:
+      case Qgis::DataType::CInt32:
+      case Qgis::DataType::ARGB32:
+      case Qgis::DataType::ARGB32_Premultiplied:
       {
-        precision = 3;
-        break;
+        return 0;
       }
       case Qgis::DataType::Float32:
+      case Qgis::DataType::CFloat32:
       {
-        precision = 9;
-        break;
+        return std::numeric_limits<float>::digits10 + 1;
       }
       case Qgis::DataType::Float64:
+      case Qgis::DataType::CFloat64:
       {
-        precision = 17;
-        break;
+        return std::numeric_limits<double>::digits10 + 1;
       }
-      default:
+      case Qgis::DataType::UnknownDataType:
       {
-        precision = 9;
+        return std::numeric_limits<double>::digits10 + 1;
       }
     }
-    return QLocale().toString( value, 'f', precision );
   }
-
 }
 
 //

diff --git a/src/gui/qgsguiutils.h b/src/gui/qgsguiutils.h
@@ -194,9 +194,18 @@ namespace QgsGuiUtils
   /**
    * Returns a localized string representation of the \a value with the appropriate number of
    * decimals supported by the \a rasterDataType.
+   * Note that for floating point types the number of decimals may exceed the actual internal
+   * precision because the precision is always calculated on the mantissa and the conversion to
+   * string interprets the precision as decimal places.
    * \since QGIS 3.16
    */
-  QString displayValue( const Qgis::DataType rasterDataType, const double value );
+  QString displayValueWithMaximumDecimals( const Qgis::DataType rasterDataType, const double value );
+
+  /**
+   * Returns the maximum number of significant digits a for the given \a rasterDataType.
+   * \since QGIS 3.16
+   */
+  int significantDigits( const Qgis::DataType rasterDataType );
 
 }
 

diff --git a/src/gui/raster/qgscolorrampshaderwidget.cpp b/src/gui/raster/qgscolorrampshaderwidget.cpp
@@ -102,11 +102,6 @@ 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( mLabelPrecisionUseDefault, &QCheckBox::toggled, this, [ = ]
-  {
-    autoLabel();
-    mPrecisionSpinBox->setEnabled( ! mLabelPrecisionUseDefault->isChecked() );
-  } );
   connect( mPrecisionSpinBox, qgis::overload<int>::of( &QSpinBox::valueChanged ), this, [ = ]( int ) { autoLabel(); } );
 }
 
@@ -125,6 +120,18 @@ void QgsColorRampShaderWidget::setRasterDataProvider( QgsRasterDataProvider *dp
 void QgsColorRampShaderWidget::setRasterBand( int band )
 {
   mBand = band;
+  // Set the maximum number of digits in the precision spin box
+  if ( mRasterDataProvider )
+  {
+    const int maxDigits { QgsGuiUtils::significantDigits( mRasterDataProvider->dataType( mBand ) ) };
+    // Get current value
+    const int currentPrecision { mPrecisionSpinBox->value() };
+    mPrecisionSpinBox->setMaximum( maxDigits );
+    if ( currentPrecision > maxDigits )
+    {
+      mPrecisionSpinBox->setValue( maxDigits );
+    }
+  }
 }
 
 void QgsColorRampShaderWidget::setExtent( const QgsRectangle &extent )
@@ -178,20 +185,13 @@ void QgsColorRampShaderWidget::autoLabel()
   auto applyPrecision = [ = ]( const QString & value )
   {
     double val { QLocale().toDouble( value ) };
-    if ( ! mLabelPrecisionUseDefault->isChecked() )
-    {
-      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
+    if ( mPrecisionSpinBox->value() <  0 )
     {
-      return QgsGuiUtils::displayValue( mRasterDataProvider->dataType( mBand ), val );
+      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() );
   };
 
   QTreeWidgetItem *currentItem = nullptr;

diff --git a/src/gui/raster/qgssinglebandpseudocolorrendererwidget.cpp b/src/gui/raster/qgssinglebandpseudocolorrendererwidget.cpp
@@ -196,7 +196,7 @@ void QgsSingleBandPseudoColorRendererWidget::loadMinMax( int bandNo, double min,
   }
   else
   {
-    whileBlocking( mMinLineEdit )->setText( displayValue( min ) );
+    whileBlocking( mMinLineEdit )->setText( displayValueWithMaxPrecision( min ) );
   }
 
   if ( std::isnan( max ) )
@@ -205,13 +205,13 @@ void QgsSingleBandPseudoColorRendererWidget::loadMinMax( int bandNo, double min,
   }
   else
   {
-    whileBlocking( mMaxLineEdit )->setText( displayValue( max ) );
+    whileBlocking( mMaxLineEdit )->setText( displayValueWithMaxPrecision( max ) );
   }
 
   // We compare old min and new min as text because QString::number keeps a fixed number of significant
   // digits (default 6) and so loaded min/max will always differ from current one, which triggers a
   // classification, and wipe out every user modification (see https://github.com/qgis/QGIS/issues/36172)
-  if ( mMinLineEdit->text() != displayValue( min ) || mMaxLineEdit->text() != displayValue( max ) )
+  if ( mMinLineEdit->text() != displayValueWithMaxPrecision( min ) || mMaxLineEdit->text() != displayValueWithMaxPrecision( max ) )
   {
     whileBlocking( mColorRampShaderWidget )->setRasterBand( bandNo );
     whileBlocking( mColorRampShaderWidget )->setMinimumMaximumAndClassify( min, max );
@@ -221,8 +221,8 @@ void QgsSingleBandPseudoColorRendererWidget::loadMinMax( int bandNo, double min,
 
 void QgsSingleBandPseudoColorRendererWidget::loadMinMaxFromTree( double min, double max )
 {
-  whileBlocking( mMinLineEdit )->setText( displayValue( min ) );
-  whileBlocking( mMaxLineEdit )->setText( displayValue( max ) );
+  whileBlocking( mMinLineEdit )->setText( displayValueWithMaxPrecision( min ) );
+  whileBlocking( mMaxLineEdit )->setText( displayValueWithMaxPrecision( max ) );
   minMaxModified();
 }
 
@@ -232,7 +232,7 @@ void QgsSingleBandPseudoColorRendererWidget::setLineEditValue( QLineEdit *lineEd
   QString s;
   if ( !std::isnan( value ) )
   {
-    s = displayValue( value );
+    s = displayValueWithMaxPrecision( value );
   }
   lineEdit->setText( s );
 }
@@ -279,11 +279,11 @@ void QgsSingleBandPseudoColorRendererWidget::minMaxModified()
   mMinMaxWidget->userHasSetManualMinMaxValues();
 }
 
-QString QgsSingleBandPseudoColorRendererWidget::displayValue( const double value )
+QString QgsSingleBandPseudoColorRendererWidget::displayValueWithMaxPrecision( const double value )
 {
   if ( mRasterLayer->dataProvider() )
   {
-    return QgsGuiUtils::displayValue( mRasterLayer->dataProvider()->dataType( mBandComboBox->currentBand() ), value );
+    return QgsGuiUtils::displayValueWithMaximumDecimals( mRasterLayer->dataProvider()->dataType( mBandComboBox->currentBand() ), value );
   }
   else
   {

diff --git a/src/gui/raster/qgssinglebandpseudocolorrendererwidget.h b/src/gui/raster/qgssinglebandpseudocolorrendererwidget.h
@@ -81,8 +81,8 @@ class GUI_EXPORT QgsSingleBandPseudoColorRendererWidget: public QgsRasterRendere
 
     void minMaxModified();
 
-    // Convert min/max to localized display value with correct precision
-    QString displayValue( const double value );
+    // Convert min/max to localized display value with maximum precision for the current data type
+    QString displayValueWithMaxPrecision( const double value );
 
 };