improve 3D ui for directional light

src/app/3d/qgslightswidget.cpp

@@ -21,6 +21,8 @@
 
 #include <QMessageBox>
 
+#include "qwt_compass.h"
+#include "qwt_dial_needle.h"
 
 QgsLightsWidget::QgsLightsWidget( QWidget *parent )
   : QWidget( parent )
@@ -30,6 +32,18 @@ QgsLightsWidget::QgsLightsWidget( QWidget *parent )
   btnAddLight->setIcon( QIcon( QgsApplication::iconPath( "symbologyAdd.svg" ) ) );
   btnRemoveLight->setIcon( QIcon( QgsApplication::iconPath( "symbologyRemove.svg" ) ) );
 
+  mDirectionCompass = new QwtCompass( this );
+  QwtCompassScaleDraw *scaleDraw = new QwtCompassScaleDraw();
+  scaleDraw->enableComponent( QwtAbstractScaleDraw::Ticks, true );
+  scaleDraw->enableComponent( QwtAbstractScaleDraw::Backbone, false );
+  scaleDraw->setTickLength( QwtScaleDiv::MinorTick, 0 );
+  scaleDraw->setTickLength( QwtScaleDiv::MediumTick, 0 );
+  scaleDraw->setTickLength( QwtScaleDiv::MajorTick, 4 );
+  QwtScaleDiv scaleDiv = scaleDraw->scaleDiv();
+  mDirectionCompass->setScaleDraw( scaleDraw );
+  mDirectionCompass->setNeedle( new QwtDialSimpleNeedle( QwtDialSimpleNeedle::Ray, true, Qt::darkYellow, Qt::gray ) );
+  directionLightLayout->insertWidget( 3, mDirectionCompass );
+
   connect( btnAddLight, &QToolButton::clicked, this, &QgsLightsWidget::onAddLight );
   connect( btnRemoveLight, &QToolButton::clicked, this, &QgsLightsWidget::onRemoveLight );
 
@@ -50,12 +64,17 @@ QgsLightsWidget::QgsLightsWidget( QWidget *parent )
   connect( btnRemoveDirectionalLight, &QToolButton::clicked, this, &QgsLightsWidget::onRemoveDirectionalLight );
 
   connect( cboDirectionalLights, qgis::overload<int>::of( &QComboBox::currentIndexChanged ), this, &QgsLightsWidget::onCurrentDirectionalLightChanged );
-  connect( spinDirectionX, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::updateCurrentDirectionalLightParameters );
-  connect( spinDirectionY, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::updateCurrentDirectionalLightParameters );
-  connect( spinDirectionZ, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::updateCurrentDirectionalLightParameters );
+  connect( spinDirectionX, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::onSpinBoxDirectionChanged );
+  connect( spinDirectionY, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::onSpinBoxDirectionChanged );
+  connect( spinDirectionZ, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::onSpinBoxDirectionChanged );
   connect( spinDirectionalIntensity, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::updateCurrentDirectionalLightParameters );
   connect( btnDirectionalColor, &QgsColorButton::colorChanged, this, &QgsLightsWidget::updateCurrentDirectionalLightParameters );
 
+  connect( mDirectionCompass, &QwtCompass::valueChanged, spinBoxAzimuth, &QgsDoubleSpinBox::setValue );
+  connect( spinBoxAzimuth, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::onSpinBoxAzimuthChange );
+  connect( spinBoxAltitude, qgis::overload<double>::of( &QDoubleSpinBox::valueChanged ), this, &QgsLightsWidget::onSpinBoxAltitudeChange );
+  connect( sliderAltitude, &QSlider::valueChanged, spinBoxAltitude, &QgsDoubleSpinBox::setValue );
+
   tabWidget->setCurrentIndex( QgsSettings().value( QStringLiteral( "UI/last3DLightsTab" ), 1 ).toInt() );
 }
 
@@ -117,6 +136,7 @@ void QgsLightsWidget::onCurrentDirectionalLightChanged( int index )
   whileBlocking( spinDirectionZ )->setValue( light.direction().z() );
   whileBlocking( btnDirectionalColor )->setColor( light.color() );
   whileBlocking( spinDirectionalIntensity )->setValue( light.intensity() );
+  onSpinBoxDirectionChanged();
 }
 
 
@@ -211,6 +231,91 @@ void QgsLightsWidget::onRemoveDirectionalLight()
   emit directionalLightsCountChanged( cboDirectionalLights->count() );
 }
 
+void QgsLightsWidget::onSpinBoxDirectionChanged()
+{
+  double x = spinDirectionX->value();
+  double y = spinDirectionY->value();
+  double z = spinDirectionZ->value();
+  double azimuthAngle;
+  double altitudeAngle;
+
+  double horizontalVectorMagnitude = sqrt( x * x + z * z );
+  if ( horizontalVectorMagnitude == 0 )
+    azimuthAngle = 0;
+  else
+  {
+    azimuthAngle = ( asin( -x / horizontalVectorMagnitude ) ) / M_PI * 180;
+    if ( z < 0 )
+      azimuthAngle = 180 - azimuthAngle;
+    azimuthAngle = std::fmod( azimuthAngle + 360.0, 360.0 );
+  }
+
+
+  mDirectionCompass->setValue( azimuthAngle );
+  spinBoxAzimuth->setValue( azimuthAngle );
+
+  if ( horizontalVectorMagnitude == 0 )
+    altitudeAngle = y >= 0 ? 90 : -90;
+  else
+    altitudeAngle = -atan( y / horizontalVectorMagnitude ) / M_PI * 180;
+
+  spinBoxAltitude->setValue( altitudeAngle );
+  sliderAltitude->setValue( altitudeAngle );
+
+  updateCurrentDirectionalLightParameters();
+}
+
+void QgsLightsWidget::onSpinBoxAzimuthChange()
+{
+  double x = spinDirectionX->value();
+  double z = spinDirectionZ->value();
+  double horizontalVectorMagnitude = sqrt( x * x + z * z );
+
+  double azimuthValue = spinBoxAzimuth->value();
+  x = -horizontalVectorMagnitude * sin( azimuthValue / 180 * M_PI );
+  z = horizontalVectorMagnitude * cos( azimuthValue / 180 * M_PI );
+
+  whileBlocking( mDirectionCompass )->setValue( azimuthValue );
+  whileBlocking( spinDirectionX )->setValue( x );
+  whileBlocking( spinDirectionZ )->setValue( z );
+
+  updateCurrentDirectionalLightParameters();
+}
+
+void QgsLightsWidget::onSpinBoxAltitudeChange()
+{
+  double x = spinDirectionX->value();
+  double y = spinDirectionY->value();
+  double z = spinDirectionZ->value();
+  double horizontalVectorMagnitude = sqrt( x * x + z * z );
+  double vectorMagnitude = sqrt( x * x + y * y + z * z );
+
+  double altitudeValue = spinBoxAltitude->value();
+  double azimuthValue = spinBoxAzimuth->value();
+  if ( fabs( altitudeValue ) == 90 )
+  {
+    x = 0;
+    z = 0;
+    y = -vectorMagnitude * fabs( altitudeValue ) / altitudeValue;
+  }
+  else
+  {
+    if ( horizontalVectorMagnitude == 0 )
+      horizontalVectorMagnitude = vectorMagnitude * cos( altitudeValue / 180 * M_PI );;
+
+    x = -horizontalVectorMagnitude * sin( azimuthValue / 180 * M_PI );
+    z = horizontalVectorMagnitude * cos( azimuthValue / 180 * M_PI );
+    y = -tan( altitudeValue / 180 * M_PI ) * horizontalVectorMagnitude;
+  }
+
+  whileBlocking( spinDirectionX )->setValue( x );
+  whileBlocking( spinDirectionZ )->setValue( z );
+  whileBlocking( spinDirectionY )->setValue( y );
+  whileBlocking( sliderAltitude )->setValue( altitudeValue );
+
+  updateCurrentDirectionalLightParameters();
+}
+
 void QgsLightsWidget::updateLightsList()
 {
   cboLights->blockSignals( true );

src/app/3d/qgslightswidget.h

@@ -23,6 +23,7 @@
 #include "qgspointlightsettings.h"
 #include "qgsdirectionallightsettings.h"
 
+class QwtCompass;
 
 /**
  * Widget for configuration of lights in 3D map scene
@@ -53,6 +54,9 @@ class QgsLightsWidget : public QWidget, private Ui::QgsLightsWidget
     void updateCurrentDirectionalLightParameters();
     void onAddDirectionalLight();
     void onRemoveDirectionalLight();
+    void onSpinBoxDirectionChanged();
+    void onSpinBoxAzimuthChange();
+    void onSpinBoxAltitudeChange();
   private:
     void updateLightsList();
     void updateDirectionalLightsList();
@@ -60,6 +64,7 @@ class QgsLightsWidget : public QWidget, private Ui::QgsLightsWidget
   private:
     QList<QgsPointLightSettings> mPointLights;
     QList<QgsDirectionalLightSettings> mDirectionalLights;
+    QwtCompass *mDirectionCompass = nullptr;
 };
 
 #endif // QGSLIGHTSWIDGET_H

src/ui/3d/qgslightswidget.ui

@@ -216,10 +216,10 @@
       <layout class="QGridLayout" name="gridLayout_4">
        <item row="1" column="0" colspan="3">
         <layout class="QGridLayout" name="gridLayout_3">
-         <item row="3" column="1">
+         <item row="4" column="1">
           <widget class="QgsDoubleSpinBox" name="spinDirectionZ">
            <property name="decimals">
-            <number>1</number>
+            <number>2</number>
            </property>
            <property name="minimum">
             <double>-9999999.000000000000000</double>
@@ -229,7 +229,64 @@
            </property>
           </widget>
          </item>
-         <item row="4" column="1">
+         <item row="4" column="0">
+          <widget class="QLabel" name="label_10">
+           <property name="text">
+            <string>Z</string>
+           </property>
+          </widget>
+         </item>
+         <item row="5" column="0">
+          <widget class="QLabel" name="label_16">
+           <property name="text">
+            <string>Color</string>
+           </property>
+          </widget>
+         </item>
+         <item row="2" column="1">
+          <widget class="QgsDoubleSpinBox" name="spinDirectionX">
+           <property name="decimals">
+            <number>2</number>
+           </property>
+           <property name="minimum">
+            <double>-9999999.000000000000000</double>
+           </property>
+           <property name="maximum">
+            <double>9999999.000000000000000</double>
+           </property>
+          </widget>
+         </item>
+         <item row="3" column="0">
+          <widget class="QLabel" name="label_13">
+           <property name="text">
+            <string>Y</string>
+           </property>
+          </widget>
+         </item>
+         <item row="6" column="1">
+          <widget class="QgsDoubleSpinBox" name="spinDirectionalIntensity">
+           <property name="decimals">
+            <number>1</number>
+           </property>
+           <property name="maximum">
+            <double>999999.000000000000000</double>
+           </property>
+          </widget>
+         </item>
+         <item row="3" column="1">
+          <widget class="QgsDoubleSpinBox" name="spinDirectionY">
+           <property name="decimals">
+            <number>2</number>
+           </property>
+           <property name="minimum">
+            <double>-9999999.000000000000000</double>
+           </property>
+           <property name="maximum">
+            <double>9999999.000000000000000</double>
+           </property>
+          </widget>
+         </item>
+         <item row="5" column="1">
           <widget class="QgsColorButton" name="btnDirectionalColor">
            <property name="sizePolicy">
             <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
@@ -245,71 +302,7 @@
            </property>
           </widget>
          </item>
-         <item row="5" column="0">
-          <widget class="QLabel" name="label_14">
-           <property name="text">
-            <string>Intensity</string>
-           </property>
-          </widget>
-         </item>
          <item row="2" column="0">
-          <widget class="QLabel" name="label_13">
-           <property name="text">
-            <string>Y</string>
-           </property>
-          </widget>
-         </item>
-         <item row="3" column="0">
-          <widget class="QLabel" name="label_10">
-           <property name="text">
-            <string>Z</string>
-           </property>
-          </widget>
-         </item>
-         <item row="2" column="1">
-          <widget class="QgsDoubleSpinBox" name="spinDirectionY">
-           <property name="decimals">
-            <number>1</number>
-           </property>
-           <property name="minimum">
-            <double>-9999999.000000000000000</double>
-           </property>
-           <property name="maximum">
-            <double>9999999.000000000000000</double>
-           </property>
-          </widget>
-         </item>
-         <item row="1" column="1">
-          <widget class="QgsDoubleSpinBox" name="spinDirectionX">
-           <property name="decimals">
-            <number>1</number>
-           </property>
-           <property name="minimum">
-            <double>-9999999.000000000000000</double>
-           </property>
-           <property name="maximum">
-            <double>9999999.000000000000000</double>
-           </property>
-          </widget>
-         </item>
-         <item row="5" column="1">
-          <widget class="QgsDoubleSpinBox" name="spinDirectionalIntensity">
-           <property name="decimals">
-            <number>1</number>
-           </property>
-           <property name="maximum">
-            <double>999999.000000000000000</double>
-           </property>
-          </widget>
-         </item>
-         <item row="4" column="0">
-          <widget class="QLabel" name="label_16">
-           <property name="text">
-            <string>Color</string>
-           </property>
-          </widget>
-         </item>
-         <item row="1" column="0">
           <widget class="QLabel" name="label_17">
            <property name="text">
             <string>X</string>
@@ -323,6 +316,108 @@
            </property>
           </widget>
          </item>
+         <item row="6" column="0">
+          <widget class="QLabel" name="label_14">
+           <property name="text">
+            <string>Intensity</string>
+           </property>
+          </widget>
+         </item>
+         <item row="1" column="0" colspan="2">
+          <layout class="QHBoxLayout" name="directionLightLayout">
+           <property name="topMargin">
+            <number>11</number>
+           </property>
+           <item>
+            <spacer name="horizontalSpacer_2">
+             <property name="orientation">
+              <enum>Qt::Horizontal</enum>
+             </property>
+             <property name="sizeHint" stdset="0">
+              <size>
+               <width>40</width>
+               <height>20</height>
+              </size>
+             </property>
+            </spacer>
+           </item>
+           <item>
+            <widget class="QLabel" name="label_12">
+             <property name="text">
+              <string>Azimuth</string>
+             </property>
+            </widget>
+           </item>
+           <item>
+            <widget class="QDoubleSpinBox" name="spinBoxAzimuth">
+             <property name="suffix">
+              <string>°</string>
+             </property>
+             <property name="maximum">
+              <double>360.000000000000000</double>
+             </property>
+            </widget>
+           </item>
+           <item>
+            <widget class="QWidget" name="directionCmpassWidget" native="true"/>
+           </item>
+           <item>
+            <widget class="QLabel" name="altitudeSpinBox">
+             <property name="text">
+              <string>Altitude</string>
+             </property>
+            </widget>
+           </item>
+           <item>
+            <widget class="QDoubleSpinBox" name="spinBoxAltitude">
+             <property name="suffix">
+              <string>°</string>
+             </property>
+             <property name="minimum">
+              <double>-90.000000000000000</double>
+             </property>
+             <property name="maximum">
+              <double>90.000000000000000</double>
+             </property>
+            </widget>
+           </item>
+           <item>
+            <widget class="QSlider" name="sliderAltitude">
+             <property name="minimum">
+              <number>-90</number>
+             </property>
+             <property name="maximum">
+              <number>90</number>
+             </property>
+             <property name="tracking">
+              <bool>true</bool>
+             </property>
+             <property name="orientation">
+              <enum>Qt::Vertical</enum>
+             </property>
+             <property name="tickPosition">
+              <enum>QSlider::TicksBelow</enum>
+             </property>
+             <property name="tickInterval">
+              <number>2</number>
+             </property>
+            </widget>
+           </item>
+           <item>
+            <spacer name="horizontalSpacer">
+             <property name="orientation">
+              <enum>Qt::Horizontal</enum>
+             </property>
+             <property name="sizeHint" stdset="0">
+              <size>
+               <width>40</width>
+               <height>20</height>
+              </size>
+             </property>
+            </spacer>
+           </item>
+          </layout>
+         </item>
         </layout>
        </item>
        <item row="0" column="2">