Path: utzoo!mnetor!uunet!husc6!uwvax!oddjob!ncar!gatech!bloom-beacon!oberon!pollux.usc.edu!papa From: papa@pollux.usc.edu (Marco Papa) Newsgroups: comp.sys.amiga.tech Subject: Re: Horizontal scrolling problems Message-ID: <9003@oberon.USC.EDU> Date: 10 May 88 07:06:57 GMT References: <2465@mit-amt.MEDIA.MIT.EDU> Sender: news@oberon.USC.EDU Reply-To: papa@pollux.usc.edu (Marco Papa) Organization: Felsina Software, Los Angeles, CA Lines: 28 In article <2465@mit-amt.MEDIA.MIT.EDU> dlleigh@media-lab.media.mit.edu.UUCP (Darren L. Leigh) writes: >I am trying to create a hi-res, interlaced horizontally scrolling |display for use in my heart monitor project. I have been having some |weird problems with wide bitmaps and with the ScrollVPort function. | |When the bitmap I am using is 1024 or fewer pixels wide, the display ^^^^^^^^^^^^^ |is fine and I just get some hashing when I call ScrollVPort (I know |the docs said there would be some hashing, but that much?!?). When |the bitmap is 1025 or more pixels wide, I get junk on the screen (even ^^^^^^^^^^^^ |after clearing the associated rastport, and without doing any |scrolling). The junk seems to scroll OK, but jumps around a lot. I |don't seem to be able to draw onto the junk either. |The bitmap in question is attached to the second rasinfo structure of |a dual playfield display (many thanks to those who helped me get that |working), but I get the same problem with single playfield displays. |Am I doing something wrong? Is there a bug? Or am I just going crazy? According to the RKM manual (page 2-20 of Vol. 1 of the CBM edition) : "The big picture (called a raster and represented by the BitMap structure) can have a maximum size of 1024 by 1024. " -- Marco Papa 'Doc' -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= uucp:...!pollux!papa BIX:papa ARPAnet:pollux!papa@oberon.usc.edu "There's Alpha, Beta, Gamma and Diga!" -- Leo Schwab [quoting Rick Unland] -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=