reverted:

--- src/viscontrol.cpp	Fri Aug 12 23:18:47 2011 +0100

+++ src/viscontrol.cpp	Sat Aug 13 01:27:01 2011 +0100

@@ -670,15 +671,24 @@

 					continue;

+				//Initially assume that everything is passed through

+				//filter

+				int blockMask=0x0;

+

-				int blockMask=0xFFFF;

 				if((*it)->haveCache())

 				{

 					//Loop over the children of this filter, grab their block masks

 					for(tree<Filter *>::sibling_iterator itJ=it.begin(); itJ!=it.end();itJ++)

 					{

+

 						if((*itJ)->haveCache())

+						{

+							int curBlockMask;

+							curBlockMask=(*itJ)->getRefreshBlockMask();

+							blockMask= (blockMask & curBlockMask);

+

+						}

-							blockMask&=(*itJ)->getRefreshBlockMask();

 						else

 						{

 							blockMask&=0;