Support grid decoration

src/core/CMakeLists.txt

@@ -65,6 +65,7 @@ set(QFIELD_CORE_SRCS
     focusstack.cpp
     geometry.cpp
     geometryeditorsmodel.cpp
+    gridmodel.cpp
     identifytool.cpp
     layerobserver.cpp
     featurehistory.cpp
@@ -186,6 +187,7 @@ set(QFIELD_CORE_HDRS
     focusstack.h
     geometry.h
     geometryeditorsmodel.h
+    gridmodel.h
     identifytool.h
     layerobserver.h
     featurehistory.h

src/core/gridmodel.cpp

@@ -0,0 +1,285 @@
+/***************************************************************************
+  gridmodel.cpp - GridModel
+
+ ---------------------
+ begin                : 4.10.2024
+ copyright            : (C) 2024 by Mathieu Pellerin
+ email                : mathieu@opengis.ch
+ ***************************************************************************
+ *                                                                         *
+ *   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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "gridmodel.h"
+
+GridModel::GridModel( QObject *parent )
+  : QObject( parent )
+{
+}
+
+void GridModel::setEnabled( bool enabled )
+{
+  if ( mEnabled == enabled )
+    return;
+
+  mEnabled = enabled;
+  emit enabledChanged();
+
+  if ( mEnabled )
+  {
+    update();
+  }
+  else
+  {
+    if ( !mLines.isEmpty() || !mMarkers.isEmpty() || !mAnnotations.isEmpty() )
+    {
+      mLines.clear();
+      mMarkers.clear();
+      mAnnotations.clear();
+      emit gridChanged();
+    }
+  }
+}
+
+void GridModel::setMapSettings( QgsQuickMapSettings *mapSettings )
+{
+  if ( mMapSettings == mapSettings )
+  {
+    return;
+  }
+
+  if ( mMapSettings )
+  {
+    disconnect( mMapSettings, &QgsQuickMapSettings::visibleExtentChanged, this, &GridModel::update );
+  }
+
+  mMapSettings = mapSettings;
+  emit mapSettingsChanged();
+
+
+  if ( mMapSettings )
+  {
+    connect( mMapSettings, &QgsQuickMapSettings::visibleExtentChanged, this, &GridModel::update );
+  }
+}
+
+void GridModel::setXInterval( double interval )
+{
+  if ( mXInterval == interval )
+    return;
+
+  mXInterval = interval;
+  emit xIntervalChanged();
+
+  update();
+}
+
+void GridModel::setYInterval( double interval )
+{
+  if ( mYInterval == interval )
+    return;
+
+  mYInterval = interval;
+  emit yIntervalChanged();
+
+  update();
+}
+
+void GridModel::setXOffset( double offset )
+{
+  if ( mXOffset == offset )
+    return;
+
+  mXOffset = offset;
+  emit xOffsetChanged();
+
+  update();
+}
+
+void GridModel::setYOffset( double offset )
+{
+  if ( mYOffset == offset )
+    return;
+
+  mYOffset = offset;
+  emit yOffsetChanged();
+
+  update();
+}
+
+void GridModel::setPrepareLines( bool prepare )
+{
+  if ( mPrepareLines == prepare )
+    return;
+
+  mPrepareLines = prepare;
+  emit prepareLinesChanged();
+
+  if ( mPrepareLines )
+  {
+    update();
+  }
+  else
+  {
+    if ( !mLines.isEmpty() )
+    {
+      mLines.clear();
+      emit gridChanged();
+    }
+  }
+}
+
+void GridModel::setPrepareMarkers( bool prepare )
+{
+  if ( mPrepareMarkers == prepare )
+    return;
+
+  mPrepareMarkers = prepare;
+  emit prepareMarkersChanged();
+
+  if ( mPrepareMarkers )
+  {
+    update();
+  }
+  else
+  {
+    if ( !mMarkers.isEmpty() )
+    {
+      mMarkers.clear();
+      emit gridChanged();
+    }
+  }
+}
+
+void GridModel::setPrepareAnnotations( bool prepare )
+{
+  if ( mPrepareAnnotations == prepare )
+    return;
+
+  mPrepareAnnotations = prepare;
+  emit prepareAnnotationsChanged();
+
+  if ( mPrepareAnnotations )
+  {
+    update();
+  }
+  else
+  {
+    if ( !mAnnotations.isEmpty() )
+    {
+      mAnnotations.clear();
+      emit gridChanged();
+    }
+  }
+}
+
+void GridModel::update()
+{
+  if ( !mEnabled || !mMapSettings )
+  {
+    return;
+  }
+
+  bool hadGrid = !mLines.isEmpty() || !mMarkers.isEmpty() || !mAnnotations.isEmpty();
+
+  mLines.clear();
+  mMarkers.clear();
+  mAnnotations.clear();
+
+  const QgsRectangle visibleExtent = mMapSettings->visibleExtent();
+  double smallestScreenInterval = std::min( mXInterval / mMapSettings->mapUnitsPerPoint(), mYInterval / mMapSettings->mapUnitsPerPoint() );
+  if ( smallestScreenInterval < ( mPrepareMarkers ? 20 : 10 ) )
+  {
+    if ( hadGrid )
+    {
+      emit gridChanged();
+    }
+    return;
+  }
+
+  QList<QPointF> line;
+  QPointF intersectionPoint;
+
+  if ( mPrepareMarkers )
+  {
+    double xPos = visibleExtent.xMinimum() - std::fmod( visibleExtent.xMinimum(), mXInterval ) + mXOffset;
+    while ( xPos <= visibleExtent.xMaximum() )
+    {
+      double yPos = visibleExtent.yMinimum() - std::fmod( visibleExtent.yMinimum(), mYInterval ) + mYOffset;
+      while ( yPos <= visibleExtent.yMaximum() )
+      {
+        mMarkers << mMapSettings->coordinateToScreen( QgsPoint( xPos, yPos ) );
+        yPos += mYInterval;
+      }
+      xPos += mXInterval;
+    }
+  }
+
+  const QSizeF sceneSize = mMapSettings->outputSize() / mMapSettings->devicePixelRatio();
+  if ( mPrepareLines || mPrepareAnnotations )
+  {
+    double xPos = visibleExtent.xMinimum() - std::fmod( visibleExtent.xMinimum(), mXInterval ) + mXOffset;
+    const QLineF topBorder( QPointF( 0, 0 ), QPointF( sceneSize.width(), 0 ) );
+    const QLineF bottomBorder( QPointF( 0, sceneSize.height() ), QPointF( sceneSize.width(), sceneSize.height() ) );
+    while ( xPos <= visibleExtent.xMaximum() )
+    {
+      const QLineF currentLine( mMapSettings->coordinateToScreen( QgsPoint( xPos, visibleExtent.yMinimum() ) ), mMapSettings->coordinateToScreen( QgsPoint( xPos, visibleExtent.yMaximum() ) ) );
+
+      if ( mPrepareAnnotations )
+      {
+        if ( currentLine.intersects( topBorder, &intersectionPoint ) )
+        {
+          mAnnotations << GridAnnotation( GridAnnotation::Top, intersectionPoint, xPos );
+        }
+        if ( currentLine.intersects( bottomBorder, &intersectionPoint ) )
+        {
+          mAnnotations << GridAnnotation( GridAnnotation::Bottom, intersectionPoint, xPos );
+        }
+      }
+
+      if ( mPrepareLines )
+      {
+        line << currentLine.p1() << currentLine.p2();
+        mLines << line;
+        line.clear();
+      }
+
+      xPos += mXInterval;
+    }
+
+    double yPos = visibleExtent.yMinimum() - std::fmod( visibleExtent.yMinimum(), mYInterval ) + mYOffset;
+    const QLineF leftBorder( QPointF( 0, 0 ), QPointF( 0, sceneSize.height() ) );
+    const QLineF rightBorder( QPointF( sceneSize.width(), 0 ), QPointF( sceneSize.width(), sceneSize.height() ) );
+    while ( yPos <= visibleExtent.yMaximum() )
+    {
+      const QLineF currentLine( mMapSettings->coordinateToScreen( QgsPoint( visibleExtent.xMinimum(), yPos ) ), mMapSettings->coordinateToScreen( QgsPoint( visibleExtent.xMaximum(), yPos ) ) );
+
+      if ( mPrepareAnnotations )
+      {
+        if ( currentLine.intersects( leftBorder, &intersectionPoint ) )
+        {
+          mAnnotations << GridAnnotation( GridAnnotation::Left, intersectionPoint, yPos );
+        }
+        if ( currentLine.intersects( rightBorder, &intersectionPoint ) )
+        {
+          mAnnotations << GridAnnotation( GridAnnotation::Right, intersectionPoint, yPos );
+        }
+      }
+
+      if ( mPrepareLines )
+      {
+        line << currentLine.p1() << currentLine.p2();
+        mLines << line;
+        line.clear();
+      }
+
+      yPos += mYInterval;
+    }
+  }
+
+  emit gridChanged();
+}