[FEATURE]: offset for line pattern symbols

qgis · Aug 30, 2011 · 48c007e · 48c007e
1 parent 339d800
commit 48c007e
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Showing 11 changed files with 131 additions and 77 deletions.
diff --git a/python/core/qgscomposeritem.sip b/python/core/qgscomposeritem.sip
@@ -326,8 +326,7 @@ class QgsComposerItem: QObject, QGraphicsRectItem
     bool imageSizeConsideringRotation( double& width, double& height ) const;
     /**Calculates corner point after rotation and scaling*/
     bool cornerPointOnRotatedAndScaledRect( double& x, double& y, double width, double height ) const;
-    /**Returns a point on the line from startPoint to directionPoint that is a certain distance away from the starting point*/
-    QPointF pointOnLineWithDistance( const QPointF& startPoint, const QPointF& directionPoint, double distance ) const;
+
     /**Calculates width / height of the bounding box of a rotated rectangle (mRotation)*/
     void sizeChangedByRotation(double& width, double& height);
     /**Rotates a point / vector

diff --git a/src/core/composer/qgscomposeritem.cpp b/src/core/composer/qgscomposeritem.cpp
@@ -30,6 +30,7 @@
 #include "qgsapplication.h"
 #include "qgsrectangle.h" //just for debugging
 #include "qgslogger.h"
+#include "qgssymbollayerv2utils.h" //for pointOnLineWithDistance
 
 #include <cmath>
 
@@ -954,7 +955,7 @@ bool QgsComposerItem::imageSizeConsideringRotation( double& width, double& heigh
 
   //assume points 1 and 3 are on the rectangle boundaries. Calculate 2 and 4.
   double distM1 = sqrt(( x1 - midX ) * ( x1 - midX ) + ( y1 - midY ) * ( y1 - midY ) );
-  QPointF p2 = pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x2, y2 ), distM1 );
+  QPointF p2 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x2, y2 ), distM1 );
 
   if ( p2.x() < width && p2.x() > 0 && p2.y() < height && p2.y() > 0 )
   {
@@ -965,8 +966,8 @@ bool QgsComposerItem::imageSizeConsideringRotation( double& width, double& heigh
 
   //else assume that points 2 and 4 are on the rectangle boundaries. Calculate 1 and 3
   double distM2 = sqrt(( x2 - midX ) * ( x2 - midX ) + ( y2 - midY ) * ( y2 - midY ) );
-  QPointF p1 = pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x1, y1 ), distM2 );
-  QPointF p3 = pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x3, y3 ), distM2 );
+  QPointF p1 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x1, y1 ), distM2 );
+  QPointF p3 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x3, y3 ), distM2 );
   width = sqrt(( x2 - p1.x() ) * ( x2 - p1.x() ) + ( y2 - p1.y() ) * ( y2 - p1.y() ) );
   height = sqrt(( p3.x() - x2 ) * ( p3.x() - x2 ) + ( p3.y() - y2 ) * ( p3.y() - y2 ) );
   return true;
@@ -1036,15 +1037,6 @@ bool QgsComposerItem::cornerPointOnRotatedAndScaledRect( double& x, double& y, d
   return false;
 }
 
-QPointF QgsComposerItem::pointOnLineWithDistance( const QPointF& startPoint, const QPointF& directionPoint, double distance ) const
-{
-  double dx = directionPoint.x() - startPoint.x();
-  double dy = directionPoint.y() - startPoint.y();
-  double length = sqrt( dx * dx + dy * dy );
-  double scaleFactor = distance / length;
-  return QPointF( startPoint.x() + dx * scaleFactor, startPoint.y() + dy * scaleFactor );
-}
-
 void QgsComposerItem::sizeChangedByRotation( double& width, double& height )
 {
   if ( mRotation == 0.0 )

diff --git a/src/core/composer/qgscomposeritem.h b/src/core/composer/qgscomposeritem.h
@@ -315,8 +315,7 @@ class CORE_EXPORT QgsComposerItem: public QObject, public QGraphicsRectItem
     bool imageSizeConsideringRotation( double& width, double& height ) const;
     /**Calculates corner point after rotation and scaling*/
     bool cornerPointOnRotatedAndScaledRect( double& x, double& y, double width, double height ) const;
-    /**Returns a point on the line from startPoint to directionPoint that is a certain distance away from the starting point*/
-    QPointF pointOnLineWithDistance( const QPointF& startPoint, const QPointF& directionPoint, double distance ) const;
+
     /**Calculates width / height of the bounding box of a rotated rectangle (mRotation)*/
     void sizeChangedByRotation( double& width, double& height );
     /**Rotates a point / vector

diff --git a/src/core/composer/qgscomposermap.cpp b/src/core/composer/qgscomposermap.cpp
@@ -31,6 +31,7 @@
 
 #include "qgslabel.h"
 #include "qgslabelattributes.h"
+#include "qgssymbollayerv2utils.h" //for pointOnLineWithDistance
 
 #include <QGraphicsScene>
 #include <QGraphicsView>
@@ -881,7 +882,7 @@ void QgsComposerMap::drawGrid( QPainter* p )
     for ( ; vIt != verticalLines.constEnd(); ++vIt )
     {
       //start mark
-      crossEnd1 = pointOnLineWithDistance( vIt->second.p1(), vIt->second.p2(), mCrossLength );
+      crossEnd1 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( vIt->second.p1(), vIt->second.p2(), mCrossLength );
       p->drawLine( vIt->second.p1(), crossEnd1 );
 
       //test for intersection with every horizontal line
@@ -890,35 +891,35 @@ void QgsComposerMap::drawGrid( QPainter* p )
       {
         if ( hIt->second.intersect( vIt->second, &intersectionPoint ) == QLineF::BoundedIntersection )
         {
-          crossEnd1 = pointOnLineWithDistance( intersectionPoint, vIt->second.p1(), mCrossLength );
-          crossEnd2 = pointOnLineWithDistance( intersectionPoint, vIt->second.p2(), mCrossLength );
+          crossEnd1 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( intersectionPoint, vIt->second.p1(), mCrossLength );
+          crossEnd2 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( intersectionPoint, vIt->second.p2(), mCrossLength );
           p->drawLine( crossEnd1, crossEnd2 );
         }
       }
       //end mark
-      QPointF crossEnd2 = pointOnLineWithDistance( vIt->second.p2(), vIt->second.p1(), mCrossLength );
+      QPointF crossEnd2 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( vIt->second.p2(), vIt->second.p1(), mCrossLength );
       p->drawLine( vIt->second.p2(), crossEnd2 );
     }
 
     hIt = horizontalLines.constBegin();
     for ( ; hIt != horizontalLines.constEnd(); ++hIt )
     {
       //start mark
-      crossEnd1 = pointOnLineWithDistance( hIt->second.p1(), hIt->second.p2(), mCrossLength );
+      crossEnd1 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( hIt->second.p1(), hIt->second.p2(), mCrossLength );
       p->drawLine( hIt->second.p1(), crossEnd1 );
 
       vIt = verticalLines.constBegin();
       for ( ; vIt != verticalLines.constEnd(); ++vIt )
       {
         if ( vIt->second.intersect( hIt->second, &intersectionPoint ) == QLineF::BoundedIntersection )
         {
-          crossEnd1 = pointOnLineWithDistance( intersectionPoint, hIt->second.p1(), mCrossLength );
-          crossEnd2 = pointOnLineWithDistance( intersectionPoint, hIt->second.p2(), mCrossLength );
+          crossEnd1 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( intersectionPoint, hIt->second.p1(), mCrossLength );
+          crossEnd2 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( intersectionPoint, hIt->second.p2(), mCrossLength );
           p->drawLine( crossEnd1, crossEnd2 );
         }
       }
       //end mark
-      crossEnd1 = pointOnLineWithDistance( hIt->second.p2(), hIt->second.p1(), mCrossLength );
+      crossEnd1 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( hIt->second.p2(), hIt->second.p1(), mCrossLength );
       p->drawLine( hIt->second.p2(), crossEnd1 );
     }
 

diff --git a/src/core/symbology-ng/qgsfillsymbollayerv2.cpp b/src/core/symbology-ng/qgsfillsymbollayerv2.cpp
@@ -386,6 +386,7 @@ QgsSymbolLayerV2* QgsLinePatternFillSymbolLayer::create( const QgsStringMap& pro
   double distance = 5;
   double lineWidth = 0.5;
   QColor color( Qt::black );
+  double offset = 0.0;
 
   if ( properties.contains( "lineangle" ) )
   {
@@ -410,6 +411,12 @@ QgsSymbolLayerV2* QgsLinePatternFillSymbolLayer::create( const QgsStringMap& pro
     color = QgsSymbolLayerV2Utils::decodeColor( properties["color"] );
   }
   patternLayer->setColor( color );
+
+  if ( properties.contains( "offset" ) )
+  {
+    offset = properties["offset"].toDouble();
+  }
+  patternLayer->setOffset( offset );
   return patternLayer;
 }
 
@@ -434,75 +441,89 @@ void QgsLinePatternFillSymbolLayer::startRender( QgsSymbolV2RenderContext& conte
   }
 
   double outlinePixelWidth = context.outputPixelSize( mLineWidth );
+  double outputPixelDist = context.outputPixelSize( mDistance );
+  double outputPixelOffset = context.outputPixelSize( mOffset );
 
-  //find a suitable multiple of width and heigh
+  //depending on the angle, we might need to render into a larger image and use a subset of it
+  int dx = 0;
+  int dy = 0;
 
-  QImage patternImage( qAbs( width ), height, QImage::Format_ARGB32 );
+  QImage patternImage( width, height, QImage::Format_ARGB32 );
   patternImage.fill( 0 );
   QPainter p( &patternImage );
+
   p.setRenderHint( QPainter::Antialiasing, true );
   QPen pen( mColor );
   pen.setWidthF( outlinePixelWidth );
   pen.setCapStyle( Qt::FlatCap );
   p.setPen( pen );
 
-  //draw line and dots in the border
+  QPoint p1, p2, p3, p4, p5, p6;
   if ( doubleNear( mLineAngle, 0.0 ) || doubleNear( mLineAngle, 360.0 ) || doubleNear( mLineAngle, 180.0 ) )
   {
-    p.drawLine( QPointF( 0, height / 2.0 ), QPointF( width, height / 2.0 ) );
+    p1 = QPoint( 0, height );
+    p2 = QPoint( width, height );
+    p3 = QPoint( 0, 0 );
+    p4 = QPoint( width, 0 );
+    p5 = QPoint( 0, 2 * height );
+    p6 = QPoint( width, 2 * height );
   }
   else if ( doubleNear( mLineAngle, 90.0 ) || doubleNear( mLineAngle, 270.0 ) )
   {
-    p.drawLine( QPointF( width / 2.0, 0 ), QPointF( width / 2.0, height ) );
+    p1 = QPoint( 0, height );
+    p2 = QPoint( 0, 0 );
+    p3 = QPoint( width, height );
+    p4 = QPoint( width, 0 );
+    p5 = QPoint( -width, height );
+    p6 = QPoint( -width, 0 );
   }
   else if (( mLineAngle > 0 && mLineAngle < 90 ) || ( mLineAngle > 180 && mLineAngle < 270 ) )
   {
-    p.drawLine( QPointF( 0, height ), QPointF( width, 0 ) );
+    dx = outputPixelDist * cos(( 90 - mLineAngle ) * M_PI / 180 );
+    dy = outputPixelDist * sin(( 90 - mLineAngle ) * M_PI / 180 );
+    p1 = QPoint( 0, height );
+    p2 = QPoint( width, 0 );
+    p3 = QPoint( -dx, height - dy );
+    p4 = QPoint( width - dx, -dy );
+    p5 = QPoint( dx, height + dy );
+    p6 = QPoint( width + dx, dy );
   }
   else if (( mLineAngle < 180 ) || ( mLineAngle > 270 && mLineAngle < 360 ) )
   {
-    p.drawLine( QPointF( width, height ), QPointF( 0, 0 ) );
+    dy = outputPixelDist * cos(( 180 - mLineAngle ) * M_PI / 180 );
+    dx = outputPixelDist * sin(( 180 - mLineAngle ) * M_PI / 180 );
+    p1 = QPoint( width, height );
+    p2 = QPoint( 0, 0 );
+    p5 = QPoint( width + dx, height - dy );
+    p6 = QPoint( dx, -dy );
+    p3 = QPoint( width - dx, height + dy );
+    p4 = QPoint( -dx, dy );
   }
 
-  //todo: calculate triangles more accurately
-  double d1 = 0;
-  double d2 = 0;
-  QPolygonF triangle1, triangle2;
-  if ( mLineAngle > 0 && mLineAngle < 90 )
-  {
-    d1 = ( outlinePixelWidth / 2.0 ) / cos( mLineAngle * M_PI / 180 );
-    d2 = ( outlinePixelWidth / 2.0 ) / cos(( 90 - mLineAngle ) * M_PI / 180 );
-    triangle1 << QPointF( 0, 0 ) << QPointF( 0, d1 ) << QPointF( d2, 0 ) << QPointF( 0, 0 );
-    triangle2 << QPointF( width, height ) << QPointF( width - d2, height ) << QPointF( width, height - d1 ) << QPointF( width, height );
-  }
-  else if ( mLineAngle > 90 && mLineAngle < 180 )
+  if ( !doubleNear( mOffset, 0.0 ) ) //shift everything
   {
-    d1 = ( outlinePixelWidth / 2.0 ) / cos(( mLineAngle - 90 ) * M_PI / 180 );
-    d2 = ( outlinePixelWidth / 2.0 ) / cos(( 180 - mLineAngle ) * M_PI / 180 );
-    triangle1 << QPointF( width, 0 ) << QPointF( width - d1, 0 ) << QPointF( width, d2 ) << QPointF( width, 0 );
-    triangle2 << QPointF( 0, height ) << QPointF( 0, height - d2 ) << QPointF( d1, height ) << QPointF( 0, height );
-  }
-  else if ( mLineAngle > 180 && mLineAngle < 270 )
-  {
-    d1 = ( outlinePixelWidth / 2.0 ) / cos(( mLineAngle - 180 ) * M_PI / 180 );
-    d2 = ( outlinePixelWidth / 2.0 ) / cos(( 270 - mLineAngle ) * M_PI / 180 );
-    triangle1 << QPointF( 0, 0 ) << QPointF( 0, d1 ) << QPointF( d2, 0 ) << QPointF( 0, 0 );
-    triangle2 << QPointF( width, height ) << QPointF( width - d2, height ) << QPointF( width, height - d1 ) << QPointF( width, height );
-  }
-  else if ( mLineAngle > 270 && mLineAngle < 360 )
-  {
-    d1 = ( outlinePixelWidth / 2.0 ) / cos(( mLineAngle - 270 ) * M_PI / 180 );
-    d2 = ( outlinePixelWidth / 2.0 ) / cos(( 360 - mLineAngle ) * M_PI / 180 );
-    triangle1 << QPointF( width, 0 ) << QPointF( width - d1, 0 ) << QPointF( width, d2 ) << QPointF( width, 0 );
-    triangle2 << QPointF( 0, height ) << QPointF( 0, height - d2 ) << QPointF( d1, height ) << QPointF( 0, height );
+    QPointF p3Shift = QgsSymbolLayerV2Utils::pointOnLineWithDistance( p1, p3, outputPixelDist + outputPixelOffset );
+    p3 = QPoint( p3Shift.x(), p3Shift.y() );
+    QPointF p4Shift = QgsSymbolLayerV2Utils::pointOnLineWithDistance( p2, p4, outputPixelDist + outputPixelOffset );
+    p4 = QPoint( p4Shift.x(), p4Shift.y() );
+    QPointF p5Shift = QgsSymbolLayerV2Utils::pointOnLineWithDistance( p1, p5, outputPixelDist - outputPixelOffset );
+    p5 = QPoint( p5Shift.x(), p5Shift.y() );
+    QPointF p6Shift = QgsSymbolLayerV2Utils::pointOnLineWithDistance( p2, p6, outputPixelDist - outputPixelOffset );
+    p6 = QPoint( p6Shift.x(), p6Shift.y() );
+
+    //update p1, p2 last
+    p1 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( p1, p3, outputPixelOffset ).toPoint();
+    p2 = QgsSymbolLayerV2Utils::pointOnLineWithDistance( p2, p4, outputPixelOffset ).toPoint();
   }
 
-  p.setPen( QPen( Qt::NoPen ) );
-  p.setBrush( QBrush( mColor ) );
-  p.drawPolygon( triangle1 );
-  p.drawPolygon( triangle2 );
+  p.drawLine( p1, p2 );
+  p.drawLine( p3, p4 );
+  p.drawLine( p5, p6 );
   p.end();
 
+  //debug
+  //patternImage.save( "/home/marco/tmp/patternImage.png", "png" );
+
   //set image to mBrush
   if ( !doubleNear( context.alpha(), 1.0 ) )
   {
@@ -536,6 +557,7 @@ QgsStringMap QgsLinePatternFillSymbolLayer::properties() const
   map.insert( "distance", QString::number( mDistance ) );
   map.insert( "linewidth", QString::number( mLineWidth ) );
   map.insert( "color", QgsSymbolLayerV2Utils::encodeColor( mColor ) );
+  map.insert( "offset", QString::number( mOffset ) );
   return map;
 }
 

diff --git a/src/core/symbology-ng/qgsfillsymbollayerv2.h b/src/core/symbology-ng/qgsfillsymbollayerv2.h
@@ -157,6 +157,8 @@ class CORE_EXPORT QgsLinePatternFillSymbolLayer: public QgsImageFillSymbolLayer
     double lineWidth() const { return mLineWidth; }
     void setColor( const QColor& c ) { mColor = c; }
     QColor color() const { return mColor; }
+    void setOffset( double offset ) { mOffset = offset; }
+    double offset() const { return mOffset; }
 
   protected:
     /**Distance (in mm or map units) between lines*/
@@ -166,6 +168,8 @@ class CORE_EXPORT QgsLinePatternFillSymbolLayer: public QgsImageFillSymbolLayer
     QColor mColor;
     /**Vector line angle in degrees (0 = horizontal, counterclockwise)*/
     double mLineAngle;
+    /**Offset perpendicular to line direction*/
+    double mOffset;
 };
 
 class CORE_EXPORT QgsPointPatternFillSymbolLayer: public QgsImageFillSymbolLayer

diff --git a/src/core/symbology-ng/qgssymbollayerv2utils.cpp b/src/core/symbology-ng/qgssymbollayerv2utils.cpp
@@ -765,3 +765,12 @@ void QgsSymbolLayerV2Utils::multiplyImageOpacity( QImage* image, qreal alpha )
     }
   }
 }
+
+QPointF QgsSymbolLayerV2Utils::pointOnLineWithDistance( const QPointF& startPoint, const QPointF& directionPoint, double distance )
+{
+  double dx = directionPoint.x() - startPoint.x();
+  double dy = directionPoint.y() - startPoint.y();
+  double length = sqrt( dx * dx + dy * dy );
+  double scaleFactor = distance / length;
+  return QPointF( startPoint.x() + dx * scaleFactor, startPoint.y() + dy * scaleFactor );
+}
diff --git a/src/core/symbology-ng/qgssymbollayerv2utils.h b/src/core/symbology-ng/qgssymbollayerv2utils.h
@@ -81,6 +81,9 @@ class CORE_EXPORT QgsSymbolLayerV2Utils
 
     /**Multiplies opacity of image pixel values with a (global) transparency value*/
     static void multiplyImageOpacity( QImage* image, qreal alpha );
+
+    /**Returns a point on the line from startPoint to directionPoint that is a certain distance away from the starting point*/
+    static QPointF pointOnLineWithDistance( const QPointF& startPoint, const QPointF& directionPoint, double distance );
 };
 
 class QPolygonF;

diff --git a/src/gui/symbology-ng/qgssymbollayerv2widget.cpp b/src/gui/symbology-ng/qgssymbollayerv2widget.cpp
@@ -930,6 +930,7 @@ void QgsLinePatternFillSymbolLayerWidget::setSymbolLayer( QgsSymbolLayerV2* laye
     mAngleSpinBox->setValue( mLayer->lineAngle() );
     mDistanceSpinBox->setValue( mLayer->distance() );
     mLineWidthSpinBox->setValue( mLayer->lineWidth() );
+    mOffsetSpinBox->setValue( mLayer->offset() );
   }
 }
 
@@ -965,6 +966,15 @@ void QgsLinePatternFillSymbolLayerWidget::on_mLineWidthSpinBox_valueChanged( dou
   }
 }
 
+void QgsLinePatternFillSymbolLayerWidget::on_mOffsetSpinBox_valueChanged( double d )
+{
+  if ( mLayer )
+  {
+    mLayer->setOffset( d );
+    emit changed();
+  }
+}
+
 void QgsLinePatternFillSymbolLayerWidget::on_mColorPushButton_clicked()
 {
   if ( mLayer )