made global pressure mapping functional again
made global pressure mapping functional again


svn:9a0661a51fa546353b2044a64a194520c6caa5ad@258

b3sigma/libmypaint,achadwick/libmypaint,achadwick/libmypaint,b3sigma/libmypaint,achadwick/libmypaint,achadwick/libmypaint,b3sigma/libmypaint