Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!uwvax!uwmacc!uwmcsd1!marque!gryphon!crash!pnet01!haitex From: haitex@pnet01.cts.com (Wade Bickel) Newsgroups: comp.sys.amiga Subject: Re: Layers Lib./Clipping Message-ID: <2069@crash.cts.com> Date: Wed, 2-Dec-87 14:16:09 EST Article-I.D.: crash.2069 Posted: Wed Dec 2 14:16:09 1987 Date-Received: Sun, 6-Dec-87 08:47:09 EST Sender: news@crash.cts.com Organization: People-Net [pnet01], El Cajon, CA Lines: 44 dillon@CORY.BERKELEY.EDU (Matt Dillon) writes: >> I am about to deal with the issue of clipping in the >> program I am working on, and would like some advice on how >> to go about it. I have been told that by using the Layers >> Library functions I can do this, but my reading has neither >> confirmed nor denied this. >> >> By clipping I mean that I would like to be able to pass the >> drawing functions lines whose endpoints may not be within the > > All windows created with OpenWindow() automatically use the >layers library and clip. The rastport in the screen structure does not >use the layers library and thus does not clip. Usually one opens a >custom screen, then a backdrop window, rendering into the window. > > The simple drawing functions will clip completely, but I have >found that the more complex ones can't handle x/y values greater than >about 4096, so you still need to be a little careful. > > -Matt Thanks for the info Matt. Howerver, I am not using intuition. I have tried, and do not believe it is possible for my application. However I still need to incorporate clipping. I have a RastPort already set up, and would like to simply prevent it from drawing out into ?? memory when my points are out of bounds. I do not want to utilize the Layers Library to actually create the Display, as I would like to avoid system copper list management as much as possible. Also, can anyone give me any idea of the processing costs of implementing Layers Lib. clipping. I am working with 3-D images and must clip in Z space anyway. Will the Layers functions be faster/slower than algorithmically croping the images? Thanks again, Wade. UUCP: {cbosgd, hplabs!hp-sdd, sdcsvax, nosc}!crash!pnet01!haitex ARPA: crash!pnet01!haitex@nosc.mil INET: haitex@pnet01.CTS.COM