shiva@well.sf.ca.us (Kenneth Porter) (04/30/91)
Remember that when changing the transfer function, you should carry along the old definition. It may contain code to compensate for a non-linear marking engine, or it may have been previously modified by an enclosing application to achieve a special effect. ================================================================ % We must call existing transfer function after ours % for proper mapping of user grays to device grays. /oldtransfer currenttransfer def % Function just subtracts requested gray from 1, then % calls device transfer function. { 1 exch sub oldtransfer } bind settransfer % init page to logical "white" gsave 1 setgray clippath fill grestore ================================================================ Ken (shiva@well.sf.ca.us)