Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!rpi!uupsi!sunic!fuug!fuug.fi!s37732v From: s37732v@puukko.hut.fi (Markus Aalto) Newsgroups: comp.sys.amiga.graphics Subject: Re: How do you SHAM? Message-ID: Date: 27 Feb 91 08:42:30 GMT References: Sender: usenet@fuug.fi (USENET News System) Organization: Helsinki Univ. of Tech., Finland Lines: 36 In-Reply-To: ia0i+@andrew.cmu.edu's message of 26 Feb 91 22:31:30 GMT Nntp-Posting-Host: puukko.hut.fi How does a SHAM image work (i.e. what are the differences from standard HAM image format?) A general explanation would suffice, but if you had any example code, it would help me a great deal. Am I correct in my assumption (from reading tidbits about it) that it somehow resets the 32 main color registers for each scan-line to help reduce the "fringies" for the "HAM color" pixels? Almost right! It switches all the **16** main color registers for each scan-line because HAM can use only 16 base colors + HAM effects. Copper is very efficient for this kinda work, but it can switch one register for every 4 lores pixels (8 hires ones). This is because 680*0 is usually used for this job, and it takes lots of processing time (atleast in 68000). Thank you..... You`re welcome! **************************************************************** * Markus Aalto * s37732v@puukko.hut.fi **************************************************************** -- *********************************************************************** * Markus Aalto | Only Amiga makes it possible!!!! * * s37732v@puukko.hut.fi | Yeah! It's a sure thing! * * maalto4@otax.hut.fi | :^) * ***********************************************************************