Thordarson wrote:It worked fine on my ordinary 1040 STE back in 1996 (swedish model with rainbow tos, I think), but in Steem the 640x200 area is not showing correctly. The area of screen with 320x200 resolution however works fine, so you only lose the two scrollers when viewing it in Steem.
Strange, the main menu of the Demounstures demo has also both low and medium res and it works without problem under Steem. Display settings:
Borders: Always Show Borders
Low resolution: Double Size - No Stretch
Medium Resolution: Double Height - No Stretch
Thordarson wrote:Will have to check out the Demounstures demo - have never seen other examples on using multiple resolutions in the same screen
I found some old demos I wrote almost twenty years ago, being in the norwegian group OUCH. I found ut they worked partially on Steem (the latest release), but this one does not work properly. I am not sure if anyone has done this ting before: changing resolution in the middle of the screen. The demo is STE only, and has a bouncing raster bar in the middle of the screen that "splits" the screen in the middle, and in this area the resolution is set to 640x200, with two scrollers at two different speeds. It worked fine on my ordinary 1040 STE back in 1996 (swedish model with rainbow tos, I think), but in Steem the 640x200 area is not showing correctly. The area of screen with 320x200 resolution however works fine, so you only lose the two scrollers when viewing it in Steem.
The demo can be downloaded as a PRG file here: http://www.thordarson.no/share-out/cool_ste.prg
It was just copied straight off a floppy into a PC for several years ago, so it is not MSA or anything - just a plain PRG file.
Maybe I should post this under demos as it is unreleased, but I would like to see it work in Steem...
It would also be nice if someone using real STEs could run this demo and see if it works on their machines, as I only tested it on my own machine...
I tried your demo under Hatari (version 1.2 that should be released shortly). Only the middle scrollers are OK, because Hatari for now has problem with mixed resolution in STE mode with hardware scroll. Maybe it will be fixed in time for 1.2
As for your demo not working correctly, I think the problem may be that when restoring the bottom part of the screen to display the background picture, you're changing ff820f/65/05/07/09 during the active video display (that is before video signal is turned off to display a black right border).
Due to some jitter, these changes are not always at the same place, some of them are in the active display, others are in the right border.
From an emulation point of view, it is very hard to emulate the behaviour of the shifter when you change these video registers while the shifter is displaying data.
In Hatari, such changes are postponed to the beginning of the next line ; I don't know Steem's policy but it surely confuses it.
So, try to restore those registers 60 cycles or so later, to be sure you're doing it while in the right border (you have time to do it until you exit left border on the next line and display is on again), this should fix the problem (and even on a real STE, you should not change these during active display as this could also create some artecfacts).
Regarding mixing low/mid res, I think the very first programs that did this were the games from Magnetic Scrolls in 1986 (The Pawn, Guild of Thieves, Jinxter, ... such memories from that time !)
I think some painting programs also used mixed mode to display the image in low res and the tools in med res in the bottom of the screen (perhaps a version of Neochrome did that, can't remember)
Thordarson wrote:I tried your demo under Hatari (version 1.2 that should be released shortly). Only the middle scrollers are OK, because Hatari for now has problem with mixed resolution in STE mode with hardware scroll. Maybe it will be fixed in time for 1.2
Interesting. I tried to run it in version 1.1, made an ST image, but it bombed out with two bombs using tos 2.06 and error message with emutos. Nice if it could work in 1.2!
It sounds sensible. I think maybe it could be an idea to use the same method to stabilize the timing as in opening side borders (bit shifting after reading exact position), so that the changes appear in the exact same position every time, as I can see that the lower part flickers in a way that seems to be caused by timing variations. I also saw it might be some flickering on the raster lines too at the ends of the lines which I did not see back twenty years ago as it the monitor did not display the lines all the way.
There you awoke memories! I remember seeing the title picture of Jinxter for the first time, I was genuinely impressed. I have a feeling of that graphics on Atari ST was art, human hand-made art, while most PC graphics today is made by rendering of models, digitalising of photography/video recordings, not giving the same impression of beauty and art.
Steven Seagal wrote:The link is dead. Anybody kept this demo (1st post), I'd like to check it?
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