A quick fix for fast scrolling irc-view which may cause SIGSEGV at startup

git-svn-id: https://svn.kvirc.de/svn/trunk/kvirc@638 17fca916-40b9-46aa-a4ea-0a15b648b75c

1 files changed, 26 insertions, 13 deletions

diff --git a/src/kvirc/ui/kvi_ircview.cpp b/src/kvirc/ui/kvi_ircview.cpp
index 65f23daa6..e7a5ab702 100644
--- a/src/kvirc/ui/kvi_ircview.cpp
+++ b/src/kvirc/ui/kvi_ircview.cpp
@@ -2797,10 +2797,30 @@ void KviIrcView::fastScroll(int lines)
 		maxLineWidth -= KVI_IRCVIEW_PIXMAP_SEPARATOR_AND_DOUBLEBORDER_WIDTH;

 		defLeftCoord+=KVI_IRCVIEW_PIXMAP_AND_SEPARATOR;

 	}

+
+	if(!m_pFm)

+	{

+		// note that QFontMetrics(pa.font()) may be not the same as QFontMetrics(font())

+		// because the painter might effectively use an approximation of the QFont specified

+		// by font()... thus we need to get the double buffer and
+		// create the painter here :/
+		// Well.. this is an one-time operation so it's now expensive in fact.
+		KviDoubleBuffer doublebuffer(width(),height());

+		QPixmap * pDoubleBufferPixmap = doublebuffer.pixmap();

+		

+		QPainter pa(pDoubleBufferPixmap);

+	

+		pa.setFont(font());

+		recalcFontVariables(QFontMetrics(pa.font()),pa.fontInfo());

+	}

+
+
 	int heightToPaint = 1;

 	KviIrcViewLine * l = m_pCurLine;

-	while(lines > 0){

-		if(l){

+	while(lines > 0)
+	{

+		if(l)
+		{

 			if(maxLineWidth != l->iMaxLineWidth)calculateLineWraps(l,maxLineWidth);

 			heightToPaint += l->uLineWraps * m_iFontLineSpacing;

 			heightToPaint += (m_iFontLineSpacing + m_iFontDescent);

@@ -2808,26 +2828,19 @@ void KviIrcView::fastScroll(int lines)
 			l = l->pPrev;

 		} else lines = 0;

 	}

-/*#ifdef COMPILE_USE_QT4

-	QPainter p(this);

-	QPixmap pixmap=QPixmap::grabWidget(this,1,heightToPaint,widgetWidth -2,widgetHeight - (heightToPaint + KVI_IRCVIEW_VERTICAL_BORDER));

-	p.drawPixmap(1,1,pixmap,1,heightToPaint,widgetWidth -2,widgetHeight - (heightToPaint + KVI_IRCVIEW_VERTICAL_BORDER));

-#else

-*/

 

 	bitBlt(this,1,1,this,1,heightToPaint,widgetWidth -2,widgetHeight - (heightToPaint + KVI_IRCVIEW_VERTICAL_BORDER));

-//#endif

 

 	QRect r(0,widgetHeight - (heightToPaint + KVI_IRCVIEW_VERTICAL_BORDER),

 			widgetWidth,heightToPaint + KVI_IRCVIEW_VERTICAL_BORDER);

 

-	QPaintEvent * e = new QPaintEvent(r);

-	#if defined(COMPILE_USE_QT4) && defined(COMPILE_ON_WINDOWS) 

+#if defined(COMPILE_USE_QT4) && defined(COMPILE_ON_WINDOWS) 

 	repaint(r);

-	#else

+#else

+	QPaintEvent * e = new QPaintEvent(r);

 	paintEvent(e);

-	#endif

 	delete e;

+#endif

 

 	if(m_iLastLinkRectHeight > -1)

 	{