[QGIS Commit] r12763 - trunk/qgis/src/core/symbology-ng

[svn_qgis at osgeo.org]

Author: mhugent
Date: 2010-01-14 16:36:35 -0500 (Thu, 14 Jan 2010)
New Revision: 12763

Modified:
   trunk/qgis/src/core/symbology-ng/qgssymbollayerv2utils.cpp
   trunk/qgis/src/core/symbology-ng/qgssymbollayerv2utils.h
   trunk/qgis/src/core/symbology-ng/qgssymbolv2.cpp
Log:
Create a better fake rendercontext for symbol previews

Modified: trunk/qgis/src/core/symbology-ng/qgssymbollayerv2utils.cpp
===================================================================
--- trunk/qgis/src/core/symbology-ng/qgssymbollayerv2utils.cpp	2010-01-14 18:33:24 UTC (rev 12762)
+++ trunk/qgis/src/core/symbology-ng/qgssymbollayerv2utils.cpp	2010-01-14 21:36:35 UTC (rev 12763)
@@ -660,3 +660,19 @@
     return c.rasterScaleFactor() / c.mapToPixel().mapUnitsPerPixel();
   }
 }
+
+QgsRenderContext QgsSymbolLayerV2Utils::createRenderContext( QPainter* p )
+{
+  QgsRenderContext context;
+  context.setPainter( p );
+  context.setRasterScaleFactor( 1.0 );
+  if ( p && p->device() )
+  {
+    context.setScaleFactor( p->device()->logicalDpiX() / 25.4 );
+  }
+  else
+  {
+    context.setScaleFactor( 3.465 ); //assume 88 dpi as standard value
+  }
+  return context;
+}

Modified: trunk/qgis/src/core/symbology-ng/qgssymbollayerv2utils.h
===================================================================
--- trunk/qgis/src/core/symbology-ng/qgssymbollayerv2utils.h	2010-01-14 18:33:24 UTC (rev 12762)
+++ trunk/qgis/src/core/symbology-ng/qgssymbollayerv2utils.h	2010-01-14 21:36:35 UTC (rev 12763)
@@ -73,6 +73,8 @@
     static double lineWidthScaleFactor( QgsRenderContext& c, QgsSymbolV2::OutputUnit u );
     /**Returns scale factor painter units -> pixel dimensions*/
     static double pixelSizeScaleFactor( QgsRenderContext& c, QgsSymbolV2::OutputUnit u );
+    /**Creates a render context for a pixel based device*/
+    static QgsRenderContext createRenderContext( QPainter* p );
 };
 
 class QPolygonF;

Modified: trunk/qgis/src/core/symbology-ng/qgssymbolv2.cpp
===================================================================
--- trunk/qgis/src/core/symbology-ng/qgssymbolv2.cpp	2010-01-14 18:33:24 UTC (rev 12762)
+++ trunk/qgis/src/core/symbology-ng/qgssymbolv2.cpp	2010-01-14 21:36:35 UTC (rev 12763)
@@ -160,8 +160,7 @@
 
 void QgsSymbolV2::drawPreviewIcon( QPainter* painter, QSize size )
 {
-  QgsRenderContext context;
-  context.setPainter( painter );
+  QgsRenderContext context = QgsSymbolLayerV2Utils::createRenderContext( painter );
   QgsSymbolV2RenderContext symbolContext( context, mOutputUnit );
   for ( QgsSymbolLayerV2List::iterator it = mLayers.begin(); it != mLayers.end(); ++it )
   {
@@ -186,9 +185,7 @@
     p.drawLine( 50, 0, 50, 100 );
   }
 
-  QgsRenderContext context;
-  context.setPainter( &p );
-
+  QgsRenderContext context = QgsSymbolLayerV2Utils::createRenderContext( &p );
   startRender( context );
 
   if ( mType == QgsSymbolV2::Line )
@@ -248,7 +245,7 @@
 ////////////////////
 
 QgsSymbolV2RenderContext::QgsSymbolV2RenderContext( QgsRenderContext& c, QgsSymbolV2::OutputUnit u )
-  : mRenderContext( c ), mOutputUnit( u )
+    : mRenderContext( c ), mOutputUnit( u )
 {
 
 }
@@ -258,12 +255,12 @@
 
 }
 
-double QgsSymbolV2RenderContext::outputLineWidth(double width) const
+double QgsSymbolV2RenderContext::outputLineWidth( double width ) const
 {
   return width * QgsSymbolLayerV2Utils::lineWidthScaleFactor( mRenderContext, mOutputUnit );
 }
 
-double QgsSymbolV2RenderContext::outputPixelSize(double size) const
+double QgsSymbolV2RenderContext::outputPixelSize( double size ) const
 {
   return size * QgsSymbolLayerV2Utils::pixelSizeScaleFactor( mRenderContext, mOutputUnit );
 }