Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ucbvax!hplabs!well!ewhac From: ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab) Newsgroups: comp.sys.amiga Subject: Re: Double Buffering Keywords: copperlists, multitasking, interlace Message-ID: <4748@well.UUCP> Date: 15 Dec 87 23:35:11 GMT References: <7768@steinmetz.steinmetz.UUCP> <782@mitsumi.UUCP> <812@rmi.UUCP> Reply-To: ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab) Organization: Claus Industries, Ltd. Lines: 35 In article <812@rmi.UUCP> kkaempf@rmi.UUCP (Klaus Kaempf) writes: :In article <782@mitsumi.UUCP> jimm@mitsumi.UUCP (Jim :Mackraz) writes: :: In article <7768@steinmetz.steinmetz.UUCP> :: guilford@csv.rpi.edu (james d guilford) writes: ::: I am planning to write some animation-type software, and ::: so I looked up double buffering in the RKM. It suggested ::: that I create two screens and two sets of copper lists, ::: and then to flip screens, I just replace the copper list ::: pointers. : :Scan the copperlists (AND the intermediate copperlists!!!) :for the MOVE instructions, that will install your bitplanes, :and replace the arguments to these directly (Disable(), of :course). You will also have to set up the "struct BitMap" in :your ViewPort to reflect these new circumstances, because :someone else might call "RemakeDisplay()". DO NOT assume a :fixed layout of the copperlists! This one should be written :in assembler. : :Hey Leo! Don't _you_ have a better idea 'bout this? : Well, the procedure you just described (scanning Copper lists) is precisely what ScrollVPort() does. For example code, look at my old display hack, "Ing". It double- buffers using ScrollVPort(). You can drag the screen, depth arrange it and everything. It does glitch a tiny bit, but that is largely dependent on the Phase of The Moon. _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ Leo L. Schwab -- The Guy in The Cape ihnp4!ptsfa -\ \_ -_ Recumbent Bikes: dual ---> !{well,unicom}!ewhac O----^o The Only Way To Fly. hplabs / (pronounced "AE-wack") "Work FOR? I don't work FOR anybody! I'm just having fun." -- The Doctor