[jitter] Re: Re: Re: Re: Re: Re: erase_color with half transparancy works on one videocard, not on another

jit.gl.sketch will render the objects in the order that they appear in 
the list.  For example,"drawobject a 0,drawobject b 0,drawobject c 0" 
will render "a" first, then "b", then "c".  Look in the 
"object_messages" portion of the help patch.  It is admittedly an 
underdocumented feature, but you should be able to work it out.

Best,
Andrew B.