On Thu, 30 Jul 2009, liuting wrote: > > in canvas's imagedata,how to disposal when dx or dy < 0,the same as > dirtyX or dirtyY <0 or do nothing? I don't understand the question. -- Ian Hickson U+1047E )\._.,--....,'``. fL http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,. Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'