Dennis_Grant@CMR001.BITNET (10/24/90)
The last little while, I've been studing the screens on some of my games *very* closely, and some of them are displaying more colour than they are supposed to be able to. How? (I've heard mutterings on changing the pallette on every scanline. Is this possible? How?) ---------------------------------------------------------------------- | Dennis Grant DETUD595@CMR001.BITNET | There ain't no replacement | | Computer Science (Systems) student | for cubic displacement. | | at CMR. (The "other" MilCol) | | |--------------------------------------------------------------------| | All standard disclaimers apply | |--------------------------------------------------------------------|
sie@fulcrum.bt.co.uk (Simon Raybould) (10/25/90)
In article <901024.00324231.034868@CMR.CP6> Dennis_Grant@CMR001.BITNET writes: > > The last little while, I've been studing the screens on some of my >games *very* closely, and some of them are displaying more colour than they >are supposed to be able to. How? (I've heard mutterings on changing the >pallette on every scanline. Is this possible? How?) You are referring to SHAM where the 16 colour registers used for HAM can be reset ever scan line, appart from that it works the same as HAM. +-=-=-=-=-=-=-=-=-=-=-=-=-=-=+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+ | British Telecom Fulcrum | name : Simon John Raybould {^.^} | | Fordrough Lane | path : sie@fulcrum.bt.co.uk \~/ | | Birmingham +-----------+--------------------------| | B9 5LD | // | AMIGA B2000 | | ENGLAND | \X/AMIGA | Lattice C V5.05 | +-=-=-=-=-=-=-=-=-=-=-=-=-=-=+=-=-=-=-=-=+=-=-=-=-=-=-=-=-=-=-=-=-=-+
ovb10@erato.cs.kun.nl (ovb cursus) (10/26/90)
Dennis_Grant@CMR001.BITNET writes: > The last little while, I've been studing the screens on some of my >games *very* closely, and some of them are displaying more colour than they >are supposed to be able to. How? (I've heard mutterings on changing the >pallette on every scanline. Is this possible? How?) Is this possible?!? My gawd Dennis, haven't you heard from the Copper? Run to your local bookshop and buy any book on the Amiga, you'll find something in it about the Copper (any -->good<-- book, that is). This will shed a totally new light upon the maximum colors per screen. Good luck in your holy Quest for the Copperlist, Patrick +-----------------------------------------------------------+ | Patrick Atoon | "READY. | | University of Nijmegen | ?OUT OF DATA ERROR." | | E-mail: ovb10@cs.kun.nl | - Commodore 64 | +-------------------------+---------------------------------+
jcs@crash.cts.com (John Schultz) (10/27/90)
In article <901024.00324231.034868@CMR.CP6> Dennis_Grant@CMR001.BITNET writes: > > The last little while, I've been studing the screens on some of my >games *very* closely, and some of them are displaying more colour than they >are supposed to be able to. How? (I've heard mutterings on changing the >pallette on every scanline. Is this possible? How?) The copper can be used to reload the color registers every scanline. It can also reload color registers on each scanline (about every 4 pixels, low-res, 8 pixels high-res). Thus, if you went nuts, you could load a new palette each scanline of a 320x200x5 screen for a possible 6,400 (200x32) color screen. But, of course 12 bits of color combinations only gives 4096 different colors. Further, so much processor bandwidth would be eaten that any game using this scheme would barely move. Also, as objects moved around on different scanlines, their colors would change. Most games just modify the color palette on parts of the screen. John
pochron@cat44.cs.wisc.edu (David Pochron) (11/03/90)
In article <5287@crash.cts.com> jcs@crash.cts.com (John Schultz) writes: >low-res, 8 pixels high-res). Thus, if you went nuts, you could load >a new palette each scanline of a 320x200x5 screen for a possible 6,400 Just a quick correction here: The most colors the Copper can load per scanline is 16 - it takes too long to to load 32 colors, and the next scan line would be displayed by the time it finished. This is why there are at least two scan lines between screens. (When one is pulled down partially over another.) The really funky thing do to is to write a Copper list that changes screen resolutions mid-screen - HORIZONTALLY! It's easy to do and really impresses your friends when they see a Hi-res "window" in the middle of a lo-res display. I am really impressed by the accuracy of the Copper's "WAIT x,y" command. > John -- ------------------------------------------------------------------------------- David M. Pochron | from Rescue Rangers, _A Fly in the Ointment_ pochron@garfield.cs.wisc.edu| Gadget to Dale: "Keep the hands off the body!" -------------------------------------------------------------------------------